Other Application of Ultrasound Elastography

**113**

**Chapter 9**

**Abstract**

**1. Introduction**

with tissue stiffness [2].

*Lidia Ciobanu*

Pancreatic Elastography

Pancreatic elastography represents a challenging new procedure for inflammatory pathology or tumour masses. There are technical difficulties for accurate assessment of pancreatic stiffness due to deep localization. But the new software for both conventional and endoscopic ultrasound are promising techniques for differential diagnosis between malignant tumours and different forms of chronic pancreatitis (groove pancreatitis or autoimmune pancreatitis). Early diagnosis of chronic pancreatitis, noninvasively by transabdominal shear wave elastography, is actively studied nowadays. Elastography might offer a predictive tool for the occurrence of pancreatic fistula after pancreatoduodenectomy. This chapter introduces the recent innovation of pancreatic elastography and makes recommendations for its use.

**Keywords:** pancreas, elastography, pancreatic cancer, chronic pancreatitis

The pancreatic pathology assessment represents a challenge even today when

The results of elastography can be the strain, which has a negative correlation with tissue stiffness, and the shear wave speed, which has a positive correlation

Elastography that measures shear wave speed is classified into shear wave elastography, which uses ARFI as the method to excite shear waves, and transient elastography, in which shear waves are excited in a mechanical manner. Fibroscan™, the only transient elastography device, is not used for the pancreas due to its localization [2]. Shear wave speed might be displayed by two different methods: as

many imaging techniques are available. The differentiation between chronic pancreatitis and malignant lesions requires sometimes many imaging combined procedures, even histology, without an accurate assessment. The elastography development used the principle that the assessment of a tissue elasticity of tissue might differentiate a benign soft lesion from a malignant hard tissue. But the stiffness assessment and measurement of this small organ, deeply localised in the retroperitoneum, are difficult. High accuracy and reproducibility of pancreatic elastography are not easily obtained, as the histology is not always available [1]. Nowadays both transabdominal ultrasound (US) and endoscopic ultrasound (EUS) allow pancreatic elastography assessment. There are two types of pancreatic elastography: strain elastography and shear wave speed elastography [1]. In the case of strain elastography, the stiffness of pancreatic tissue is estimated by measuring the grade of strain generated by external pressure. For shear speed elastography, the stiffness is estimated by measuring the propagation speed of the shear wave (the transverse wave) generated by acoustic radiation force impulse (ARFI) [1].

## **Chapter 9** Pancreatic Elastography

*Lidia Ciobanu*

### **Abstract**

Pancreatic elastography represents a challenging new procedure for inflammatory pathology or tumour masses. There are technical difficulties for accurate assessment of pancreatic stiffness due to deep localization. But the new software for both conventional and endoscopic ultrasound are promising techniques for differential diagnosis between malignant tumours and different forms of chronic pancreatitis (groove pancreatitis or autoimmune pancreatitis). Early diagnosis of chronic pancreatitis, noninvasively by transabdominal shear wave elastography, is actively studied nowadays. Elastography might offer a predictive tool for the occurrence of pancreatic fistula after pancreatoduodenectomy. This chapter introduces the recent innovation of pancreatic elastography and makes recommendations for its use.

**Keywords:** pancreas, elastography, pancreatic cancer, chronic pancreatitis

#### **1. Introduction**

The pancreatic pathology assessment represents a challenge even today when many imaging techniques are available. The differentiation between chronic pancreatitis and malignant lesions requires sometimes many imaging combined procedures, even histology, without an accurate assessment. The elastography development used the principle that the assessment of a tissue elasticity of tissue might differentiate a benign soft lesion from a malignant hard tissue. But the stiffness assessment and measurement of this small organ, deeply localised in the retroperitoneum, are difficult. High accuracy and reproducibility of pancreatic elastography are not easily obtained, as the histology is not always available [1].

Nowadays both transabdominal ultrasound (US) and endoscopic ultrasound (EUS) allow pancreatic elastography assessment. There are two types of pancreatic elastography: strain elastography and shear wave speed elastography [1]. In the case of strain elastography, the stiffness of pancreatic tissue is estimated by measuring the grade of strain generated by external pressure. For shear speed elastography, the stiffness is estimated by measuring the propagation speed of the shear wave (the transverse wave) generated by acoustic radiation force impulse (ARFI) [1].

The results of elastography can be the strain, which has a negative correlation with tissue stiffness, and the shear wave speed, which has a positive correlation with tissue stiffness [2].

Elastography that measures shear wave speed is classified into shear wave elastography, which uses ARFI as the method to excite shear waves, and transient elastography, in which shear waves are excited in a mechanical manner. Fibroscan™, the only transient elastography device, is not used for the pancreas due to its localization [2]. Shear wave speed might be displayed by two different methods: as the average speed within a small region (target ROI) and as an image reflecting the distribution of the speeds in the ROI [2].

#### **2. Transabdominal ultrasound: strain elastography**

The stiffness of pancreatic tissue is estimated through transabdominal ultrasound by measuring the grade of strain generated by aortic pulsation [1–4]. The relationship between the grade of strain and the stiffness of target tissue is negative correlation: the greater the strain, the softer pancreatic tissue is. For a proper assessment, the target tissue should be located in line between the probe and the aorta [1]. A fine elastogram can be easily obtained in the pancreatic body, except for the patients with severe arteriosclerosis. The elastograms obtained in the pancreatic head and tail should be interpreted with caution [1].

Strain elastography of the pancreas can be obtained with transabdominal ultrasound (US) and with EUS.

First clinical application of US elastography had been reported with real-time tissue elastography™ (RTE) produced by Hitachi Aloka [5, 6]. In the conventional RTE, only qualitative diagnosis using colour map was possible. This technique measures compression-induced tissue deformation (strain) within a region of interest (ROI), which is visualised using a transparent colour overlaying on the B-mode image. In this colour map, the hardest tissue is displayed as blue, and the softest tissue is displayed as red. In RTE, pancreatic cystic lesions cannot be evaluated, due to artefacts, when fluid component of cyst was assessed.

The first report of the usefulness of US elastography for the pancreas in clinical practice was published by Uchida et al. in 2009 [7]. They defined typical colour map observed in US-RTE for different clinical scenarios: homogeneous colour in normal pancreas, markedly hard area with soft spots, was in pancreatic ductal adenocarcinoma, uniform and soft comparable to parenchyma in neuroendocrine tumour and mixture of various colours in chronic pancreatitis. The same authors reported the 70–80% diagnostic accuracy for pancreatic tumours of B-mode alone; when B-mode was combined with US-RTE, the diagnostic accuracy was more than 90% [7].

This qualitative diagnosis using colour map was subjective and highly operator dependent; quantitative diagnosis using strain ratio was established since the second generation of RTE. Strain ratio was defined as the ratio of the strain of reference tissue (B) divided by the strain of target tissue (A).

Strain ratio was adapted from the theory called "fat lesion ratio" reported in the breast, which means the ratio of the strain of fat around the mammary gland divided by the strain of target tissue. The initial principal considered that the stiffness of fat was almost equal in different individuals [1]. To date no consensus exists for the reference area, on non-tumorous area inside the pancreatic parenchyma [8, 9] or on red area around the pancreas, estimated to be fat [10, 11]. There is no evidence if red area around pancreas is really fat. The strain ratios calculated for the same target tissue quite differ according to wherever the reference area is set [1].

The cutoff levels of strain ratio for differential diagnosis between malignant and benign varied in reported studies [9–11], meaning that pancreatic RTE is highly operator dependent and lacks adequate reproducibility.

A fine B-mode image is required for a fine elastogram, and this is obtained within 6 cm in depth from the body surface in US. Therefore, pancreatic elastogram is quite difficult in the obese. Also B-mode image is easily affected by gastrointestinal gas in US. These problems will occur less frequently in EUS.

**115**

*Pancreatic Elastography*

as possible.

abdominal wall.

*DOI: http://dx.doi.org/10.5772/intechopen.89965*

• The patient should hold his breath.

in a range of 5–10 pulsations.

media is not confirmed yet [14].

• The most important is to obtain a quality B-mode images with as few artefacts

• Examination is made from the epigastric fossa in a dorsal position, (semi)

• No vibration should be caused by the probe, which should lightly touch the

• Two settings for ROI are accepted [12]: (1) ROI is set only within the target area; (2) ROI is set both within the target area and the surrounding tissue. The

• The colours in an elastogram minutely vary with the passage of time according to cardiovascular pulsation. It is desirable that elastograms with good reproducibility are taken at every pulsation by recording the images of elastograms

For this type of elastography, emission of ARFI is possible for the entire pancreas. Virtual Touch™ quantification (VTQ ) produced by Siemens is a representative instrument. VTQ displays the stiffness of pancreatic tissue digitally shear wave velocity being measured. SWV is expressed in m/s. If an error occurs, X,XX m/s is

Even if this technique is very promising for the pancreas, there are some issue to be considered. There is a limit to the acoustic radiation force impulse that is certainly safe within the body [2]. Also, when the tissue in the ROI is hard, measurement error tends to occur, because it is difficult to generate sufficient shear waves. When SWV of a pancreatic tumour cannot be assessed, ROI should be placed on a tip of the tumour [2]. If the target area is far from the probe, the attenuation of the focused ultrasound reduces the acoustic radiation force impulse, which in turn reduces the amplitude of the shear waves, making it difficult to detect the shear waves [12]. The safety standards are accomplished by the focused ultrasound [2], but the transmission waveform and wavelength are different from the usual ultrasonic pulses. A concern is represented by its influence on the body, through a possible increase in temperature [13]. Its safety in simultaneous use with contrast

It is recommended to repeat three times the same measurement for the same site about if the reproducibility is high. If the reproducibility is low, a measurement

New ARFI software are developed (ElastPQ™ (Philips), Virtual Touch™ IQ:

Instead the Shear Wave™ Elastography (SWE) (Super Sonic Imaging) uses a new approach. In SWE, ultrasonic beams are continuously emitted to different depths in the tissue, and thus a conically shaped wave surface of shear waves is formed [2]. By an ultrafast imaging method, the shear wave speed is measured. The transducers repeat outgoing/incoming transmissions of ultrasonic waves. A colour map is displayed in the ROI, which can be defined in any location [2]. The mean ± SD, the minimum value, and the maximum value of the shear wave speed

should be repeated 10 times for the same site and the median is used [2].

VTIQ (Siemens)), but their use for the pancreatic pathology is still limited.

second is recommended for neoplastic cancer assessment.

**3. Transabdominal ultrasound: shear wave elastography**

displayed on the right part of the screen instead of digits [1].

sitting position, or left lateral decubitus position.

Recommendations to obtain a quality elastogram on B-mode US [2]:

*Ultrasound Elastography*

distribution of the speeds in the ROI [2].

**2. Transabdominal ultrasound: strain elastography**

head and tail should be interpreted with caution [1].

to artefacts, when fluid component of cyst was assessed.

reference tissue (B) divided by the strain of target tissue (A).

operator dependent and lacks adequate reproducibility.

nal gas in US. These problems will occur less frequently in EUS.

ultrasound (US) and with EUS.

the average speed within a small region (target ROI) and as an image reflecting the

The stiffness of pancreatic tissue is estimated through transabdominal ultrasound by measuring the grade of strain generated by aortic pulsation [1–4]. The relationship between the grade of strain and the stiffness of target tissue is negative correlation: the greater the strain, the softer pancreatic tissue is. For a proper assessment, the target tissue should be located in line between the probe and the aorta [1]. A fine elastogram can be easily obtained in the pancreatic body, except for the patients with severe arteriosclerosis. The elastograms obtained in the pancreatic

Strain elastography of the pancreas can be obtained with transabdominal

First clinical application of US elastography had been reported with real-time tissue elastography™ (RTE) produced by Hitachi Aloka [5, 6]. In the conventional RTE, only qualitative diagnosis using colour map was possible. This technique measures compression-induced tissue deformation (strain) within a region of interest (ROI), which is visualised using a transparent colour overlaying on the B-mode image. In this colour map, the hardest tissue is displayed as blue, and the softest tissue is displayed as red. In RTE, pancreatic cystic lesions cannot be evaluated, due

The first report of the usefulness of US elastography for the pancreas in clinical practice was published by Uchida et al. in 2009 [7]. They defined typical colour map observed in US-RTE for different clinical scenarios: homogeneous colour in normal pancreas, markedly hard area with soft spots, was in pancreatic ductal adenocarcinoma, uniform and soft comparable to parenchyma in neuroendocrine tumour and mixture of various colours in chronic pancreatitis. The same authors reported the 70–80% diagnostic accuracy for pancreatic tumours of B-mode alone; when B-mode was combined with US-RTE, the diagnostic accuracy was more than

This qualitative diagnosis using colour map was subjective and highly operator dependent; quantitative diagnosis using strain ratio was established since the second generation of RTE. Strain ratio was defined as the ratio of the strain of

Strain ratio was adapted from the theory called "fat lesion ratio" reported in the breast, which means the ratio of the strain of fat around the mammary gland divided by the strain of target tissue. The initial principal considered that the stiffness of fat was almost equal in different individuals [1]. To date no consensus exists for the reference area, on non-tumorous area inside the pancreatic parenchyma [8, 9] or on red area around the pancreas, estimated to be fat [10, 11]. There is no evidence if red area around pancreas is really fat. The strain ratios calculated for the same target tissue quite differ according to wherever the reference area is set [1]. The cutoff levels of strain ratio for differential diagnosis between malignant and benign varied in reported studies [9–11], meaning that pancreatic RTE is highly

A fine B-mode image is required for a fine elastogram, and this is obtained within 6 cm in depth from the body surface in US. Therefore, pancreatic elastogram is quite difficult in the obese. Also B-mode image is easily affected by gastrointesti-

Recommendations to obtain a quality elastogram on B-mode US [2]:

**114**

90% [7].


### **3. Transabdominal ultrasound: shear wave elastography**

For this type of elastography, emission of ARFI is possible for the entire pancreas. Virtual Touch™ quantification (VTQ ) produced by Siemens is a representative instrument. VTQ displays the stiffness of pancreatic tissue digitally shear wave velocity being measured. SWV is expressed in m/s. If an error occurs, X,XX m/s is displayed on the right part of the screen instead of digits [1].

Even if this technique is very promising for the pancreas, there are some issue to be considered. There is a limit to the acoustic radiation force impulse that is certainly safe within the body [2]. Also, when the tissue in the ROI is hard, measurement error tends to occur, because it is difficult to generate sufficient shear waves. When SWV of a pancreatic tumour cannot be assessed, ROI should be placed on a tip of the tumour [2]. If the target area is far from the probe, the attenuation of the focused ultrasound reduces the acoustic radiation force impulse, which in turn reduces the amplitude of the shear waves, making it difficult to detect the shear waves [12]. The safety standards are accomplished by the focused ultrasound [2], but the transmission waveform and wavelength are different from the usual ultrasonic pulses. A concern is represented by its influence on the body, through a possible increase in temperature [13]. Its safety in simultaneous use with contrast media is not confirmed yet [14].

It is recommended to repeat three times the same measurement for the same site about if the reproducibility is high. If the reproducibility is low, a measurement should be repeated 10 times for the same site and the median is used [2].

New ARFI software are developed (ElastPQ™ (Philips), Virtual Touch™ IQ: VTIQ (Siemens)), but their use for the pancreatic pathology is still limited.

Instead the Shear Wave™ Elastography (SWE) (Super Sonic Imaging) uses a new approach. In SWE, ultrasonic beams are continuously emitted to different depths in the tissue, and thus a conically shaped wave surface of shear waves is formed [2]. By an ultrafast imaging method, the shear wave speed is measured. The transducers repeat outgoing/incoming transmissions of ultrasonic waves. A colour map is displayed in the ROI, which can be defined in any location [2]. The mean ± SD, the minimum value, and the maximum value of the shear wave speed in the ROI are displayed. A ratio is calculated when two ROIs in different locations are compared. The study conducted by Arda et al. [15] reported measurement of stiffness for normal pancreas: 11.1 ± 3.2 kPa for males and 10.8 ± 3.1 kPa for females.

#### **4. Echo-endoscopy elastography: strain elastography**

The first report of EUS elastography was published in 2005 by Hirooka et al. [5]. Then many papers reported their experience using RTE for pancreatic EUS elastography, being for many years the only system available. In RTE obtained by EUS, the diagnosis is qualitative. It is recommended that the ROI to be set to include peripancreatic tissue [2]. Red colour corresponds to the softest tissue within ROI, and blue corresponds to the hardest tissue within ROI. The remaining tissue is displayed as a coordinated colour between red and blue according to its stiffness. As the colour map depends on the size of ROI in RTE, it is not an absolute one [1].

Some technique aspects should be kept in mind for a qualitative elastogram [2]. The EUS probe should be lightly touching the wall of the stomach or the duodenum. The selected image must be without artefacts. The ultrasonic beam should be towards the aorta, and the strain should be generated in the depth direction. The RTE image should be stably generated for a certain period (5 s or longer in normal cases). For the evaluation of vibration energy, it would be preferable to refer to a strain indicator or to a strain graph. A good-quality B-mode image should be obtained to suit the RTE image [2].

The main debated issue was the differentiation of benign vs. malignant. The diagnostic criteria to differentiate malignancy from benignancy considered two aspects: (1) the dominant colour within colour map and (2) the homogeneity of colour map [1].

In a multicentre study on 121 patients with pancreatic tumours (92 malignant and 29 benign), Giovannini et al. [16] proposed a scoring system: score 1, homogeneous green represents normal tissue; score 2, heterogeneous soft tissue (green, yellow, and red) corresponds to inflammatory tissue; score 3, mixed colour or honeycombed can be attributed to any pathology; score 4, small green central area surrounded by mainly blue; and score 5, mainly blue with heterogeneous green and red, represents advanced malignant lesion. Scores 1 and 2 were considered benign, and scores 4 and 5 were assigned to malignant pathology. The sensitivity and specificity for this score were 92.3 and 80% [16].

The (semi) quantitative evaluation is possible, being more objective, but the analytical procedure is complicated. The image quantitative analysis reported included strain ratio [9, 10, 17], strain histogram [18, 19], and neural network [20–22]. A comparison between different analysis methods has not been conducted, so there is no consensus about which of these methods is the best.

#### **5. Clinical applications for pancreatic elastography**

Uchida et al. [7] published the first report evaluating the usefulness of US elastography for the pancreas in 2009. They reviewed elastograms performed for 10 normal pancreas and reported the typical colour map for normal pancreas assessed by RTE as homogeneous colour.

The normal reference values of pancreas stiffness using ARFI elastography through Virtual Touch Tissue Quantification (Siemens) were reported by Zaro et al. in 2016 [23]: from the entire parenchyma—1.216 m/s ± 0.36 (head, 1.224 m/s; body, 1.227 m/s; and tail, 1.191 m/s) [23]. Another study found a significant correlation

**117**

**Figure 2.**

**Figure 1.**

*Pancreatic Elastography*

comparison with EUS.

*DOI: http://dx.doi.org/10.5772/intechopen.89965*

11.1 ± 3.2 kPa for males and 10.8 ± 3.1 kPa for females.

**6. Benign vs. malignant mass pancreatic lesions**

diagnosis between benign and malignant focal lesions.

*green and red corresponding to score 5 from Giovannini classification.*

between increasing age and elastographic parameters [24]. Using SWE (Super Sonic Imaging) Arda et al. [15] reported measurement of stiffness for normal pancreas:

The most frequent use of elastography in pancreatic pathology is for differential

Uchida et al. [7] used strain elastography with US to evaluate the colour patterns of the pancreatic cancers, pancreatic endocrine tumours, and chronic pancreatitis. They concluded that adding strain elastography to the B-mode observations the

The number of reports on strain elastography with US is extremely small in

*Advanced pancreatic adenocarcinoma assessed by EUS-RTE. Elastogram is mainly blue with heterogeneous* 

*Small neuroendocrine tumour at the tail of the pancreas assessed by EUS-RTE. Elastogram depicts heterogeneous small points surrounded by mainly blue corresponding to score 4 from Giovannini classification.*

#### *Pancreatic Elastography DOI: http://dx.doi.org/10.5772/intechopen.89965*

*Ultrasound Elastography*

in the ROI are displayed. A ratio is calculated when two ROIs in different locations are compared. The study conducted by Arda et al. [15] reported measurement of stiffness for normal pancreas: 11.1 ± 3.2 kPa for males and 10.8 ± 3.1 kPa for females.

The first report of EUS elastography was published in 2005 by Hirooka et al. [5]. Then many papers reported their experience using RTE for pancreatic EUS elastography, being for many years the only system available. In RTE obtained by EUS, the diagnosis is qualitative. It is recommended that the ROI to be set to include peripancreatic tissue [2]. Red colour corresponds to the softest tissue within ROI, and blue corresponds to the hardest tissue within ROI. The remaining tissue is displayed as a coordinated colour between red and blue according to its stiffness. As the colour

Some technique aspects should be kept in mind for a qualitative elastogram [2]. The EUS probe should be lightly touching the wall of the stomach or the duodenum. The selected image must be without artefacts. The ultrasonic beam should be towards the aorta, and the strain should be generated in the depth direction. The RTE image should be stably generated for a certain period (5 s or longer in normal cases). For the evaluation of vibration energy, it would be preferable to refer to a strain indicator or to a strain graph. A good-quality B-mode image should be

The main debated issue was the differentiation of benign vs. malignant. The diagnostic criteria to differentiate malignancy from benignancy considered two aspects: (1) the dominant colour within colour map and (2) the homogeneity of

In a multicentre study on 121 patients with pancreatic tumours (92 malignant and 29 benign), Giovannini et al. [16] proposed a scoring system: score 1, homogeneous green represents normal tissue; score 2, heterogeneous soft tissue (green, yellow, and red) corresponds to inflammatory tissue; score 3, mixed colour or honeycombed can be attributed to any pathology; score 4, small green central area surrounded by mainly blue; and score 5, mainly blue with heterogeneous green and red, represents advanced malignant lesion. Scores 1 and 2 were considered benign, and scores 4 and 5 were assigned to malignant pathology. The sensitivity and

The (semi) quantitative evaluation is possible, being more objective, but the analytical procedure is complicated. The image quantitative analysis reported included strain ratio [9, 10, 17], strain histogram [18, 19], and neural network [20–22]. A comparison between different analysis methods has not been conducted,

Uchida et al. [7] published the first report evaluating the usefulness of US elastography for the pancreas in 2009. They reviewed elastograms performed for 10 normal pancreas and reported the typical colour map for normal pancreas assessed

The normal reference values of pancreas stiffness using ARFI elastography through Virtual Touch Tissue Quantification (Siemens) were reported by Zaro et al. in 2016 [23]: from the entire parenchyma—1.216 m/s ± 0.36 (head, 1.224 m/s; body, 1.227 m/s; and tail, 1.191 m/s) [23]. Another study found a significant correlation

so there is no consensus about which of these methods is the best.

**5. Clinical applications for pancreatic elastography**

**4. Echo-endoscopy elastography: strain elastography**

map depends on the size of ROI in RTE, it is not an absolute one [1].

obtained to suit the RTE image [2].

specificity for this score were 92.3 and 80% [16].

by RTE as homogeneous colour.

colour map [1].

**116**

between increasing age and elastographic parameters [24]. Using SWE (Super Sonic Imaging) Arda et al. [15] reported measurement of stiffness for normal pancreas: 11.1 ± 3.2 kPa for males and 10.8 ± 3.1 kPa for females.

#### **6. Benign vs. malignant mass pancreatic lesions**

The most frequent use of elastography in pancreatic pathology is for differential diagnosis between benign and malignant focal lesions.

The number of reports on strain elastography with US is extremely small in comparison with EUS.

Uchida et al. [7] used strain elastography with US to evaluate the colour patterns of the pancreatic cancers, pancreatic endocrine tumours, and chronic pancreatitis. They concluded that adding strain elastography to the B-mode observations the

#### **Figure 1.**

*Advanced pancreatic adenocarcinoma assessed by EUS-RTE. Elastogram is mainly blue with heterogeneous green and red corresponding to score 5 from Giovannini classification.*

#### **Figure 2.**

*Small neuroendocrine tumour at the tail of the pancreas assessed by EUS-RTE. Elastogram depicts heterogeneous small points surrounded by mainly blue corresponding to score 4 from Giovannini classification.* diagnosis sensitivity is improved [7]. Kawada et al. [8] reported the use of strain ratio to distinguish between malignancy and benignancy of pancreatic solid tumours. The evaluation of the pancreatic tumours by transabdominal shear wave elastography was reported by Zaro et al. [25] in a pilot studied. The mean SWV

#### **Figure 3.**

*(a) EUS B-mode. Dilated common bile duct and suspicion of periampular tumour. (b) A "tumour-like image, suspected of malignancy" on elastogram, due to its blue (hard) appearance. This false elastogram is due to the angulations of distal tip of echo-endoscope. (c) A correct assessment of the stiffness of the ampular region displays a mixed inflamed tissue: heterogeneous soft tissue (green and red) corresponding to score 2 in Giovannini classification.*

**119**

being 77%.

*Pancreatic Elastography*

data.

*DOI: http://dx.doi.org/10.5772/intechopen.89965*

neuroendocrine tumours are displayed in **Figures 1** and **2**.

the technical adjustments should be rechecked.

diagnostic criteria are operator dependent.

**7. Chronic pancreatitis**

of the pathological parenchyma indicated an increase of the SWV at the tumoral (cephalic) level corresponding to 1.54 ± 0.32 m/s compared to 1.21 ± 0.27 m/s for normal pancreas in the control group. Future research is needed to validate this

Most reports regarding EUS elastography for the pancreas are associated with the differential diagnosis between benign and malignant solid pancreatic tumours, being published several meta-analyses related to the differential diagnosis of pancreatic tumours [26, 27]. Elastograms for pancreatic adenocarcinoma and

The sensitivity of EUS elastography for the differential diagnosis of pancreatic tumours is reported to be excellent ranging from 95 to 99%, while its specificity is reported to be inadequate ranging from 67 to 76% [1, 26, 27]. This low specificity is explained by the increased stiffness of benign nodule from chronic pancreatitis due to severe fibrosis. Fine needle aspiration through EUS is still mandatory even in cases with proper assessment of pancreatic tissue stiffness. There are few selective cases in which EUS-FNA cannot be performed, and the malignant diagnosis arguments include elastography [28]. But consensus criteria for differential diagnosis

In clinical practice there are many challenging diagnosis. The images obtained with EUS elastography should be integrated in the clinical context of the patient, being complementary to other imaging techniques. Small tumour-like images, with suggestive malignant features at elastogram, should be interpreted with caution. To assess the quality and reproducibility of the elastography image, a consistent colour pattern obtained in a number of consecutive frames is indicated. If there are different elastograms obtained for the same tumour-like image (**Figure 3a**–**c**), all

Chronic pancreatitis is frequently diagnosed in advance stages. Echo-endoscopy

Shear wave elastography using transabdominal US might be an objective and noninvasive method for the early diagnosis of pancreatic fibrosis. Yashima et al. [29] subjected 46 patients with chronic pancreatitis and 52 normal pancreas and measured SWV at the head, the body, and the tail of the pancreas for 10 times in each case and reported a sensitivity of 75% and a specificity of 72% for detection of chronic pancreatitis. They also determined the cutoff of SWV optimal for diagnosing chronic pancreatitis as 1.40 m/s by ROC analysis. Multivariate analysis detected that severe alcohol intake (OR = 3.87, p = 0.005) and deeper depth of the pancreas from the body surface ≥4.2 cm (OR = 0.10, p = 0.002) were associated with the stiffness of the pancreas (>1.40 m/s) [12]. Kuwahara et al. [30] reported that chronic pancreatitis might be diagnosed noninvasively and objectively using SW-EG without performing EUS, the diagnosis accuracy

Many reports evaluated the accuracy of EUS elastography for the diagnosis of pancreatic fibrosis. An elastogram in a patient with chronic pancreatitis is displayed in **Figure 4**. Itoh et al. [18] performed EUS elastography preoperatively for the proximal side of the pancreatic tumour and compared the elastograms with microscopic findings of the resected specimens. They found significant correlation between objective parameters assessed by elastography (mean, standard deviation, skewness, kurtosis) and the grade of fibrosis evaluated by histology. Iglesias-Garcia

may be a useful method for the early diagnosis of chronic pancreatitis, even its

between malignant and benign pancreatic tumours were not established.

#### *Pancreatic Elastography DOI: http://dx.doi.org/10.5772/intechopen.89965*

*Ultrasound Elastography*

**118**

**Figure 3.**

*Giovannini classification.*

*(a) EUS B-mode. Dilated common bile duct and suspicion of periampular tumour. (b) A "tumour-like image, suspected of malignancy" on elastogram, due to its blue (hard) appearance. This false elastogram is due to the angulations of distal tip of echo-endoscope. (c) A correct assessment of the stiffness of the ampular region displays a mixed inflamed tissue: heterogeneous soft tissue (green and red) corresponding to score 2 in* 

diagnosis sensitivity is improved [7]. Kawada et al. [8] reported the use of strain ratio to distinguish between malignancy and benignancy of pancreatic solid tumours. The evaluation of the pancreatic tumours by transabdominal shear wave elastography was reported by Zaro et al. [25] in a pilot studied. The mean SWV

of the pathological parenchyma indicated an increase of the SWV at the tumoral (cephalic) level corresponding to 1.54 ± 0.32 m/s compared to 1.21 ± 0.27 m/s for normal pancreas in the control group. Future research is needed to validate this data.

Most reports regarding EUS elastography for the pancreas are associated with the differential diagnosis between benign and malignant solid pancreatic tumours, being published several meta-analyses related to the differential diagnosis of pancreatic tumours [26, 27]. Elastograms for pancreatic adenocarcinoma and neuroendocrine tumours are displayed in **Figures 1** and **2**.

The sensitivity of EUS elastography for the differential diagnosis of pancreatic tumours is reported to be excellent ranging from 95 to 99%, while its specificity is reported to be inadequate ranging from 67 to 76% [1, 26, 27]. This low specificity is explained by the increased stiffness of benign nodule from chronic pancreatitis due to severe fibrosis. Fine needle aspiration through EUS is still mandatory even in cases with proper assessment of pancreatic tissue stiffness. There are few selective cases in which EUS-FNA cannot be performed, and the malignant diagnosis arguments include elastography [28]. But consensus criteria for differential diagnosis between malignant and benign pancreatic tumours were not established.

In clinical practice there are many challenging diagnosis. The images obtained with EUS elastography should be integrated in the clinical context of the patient, being complementary to other imaging techniques. Small tumour-like images, with suggestive malignant features at elastogram, should be interpreted with caution. To assess the quality and reproducibility of the elastography image, a consistent colour pattern obtained in a number of consecutive frames is indicated. If there are different elastograms obtained for the same tumour-like image (**Figure 3a**–**c**), all the technical adjustments should be rechecked.

#### **7. Chronic pancreatitis**

Chronic pancreatitis is frequently diagnosed in advance stages. Echo-endoscopy may be a useful method for the early diagnosis of chronic pancreatitis, even its diagnostic criteria are operator dependent.

Shear wave elastography using transabdominal US might be an objective and noninvasive method for the early diagnosis of pancreatic fibrosis. Yashima et al. [29] subjected 46 patients with chronic pancreatitis and 52 normal pancreas and measured SWV at the head, the body, and the tail of the pancreas for 10 times in each case and reported a sensitivity of 75% and a specificity of 72% for detection of chronic pancreatitis. They also determined the cutoff of SWV optimal for diagnosing chronic pancreatitis as 1.40 m/s by ROC analysis. Multivariate analysis detected that severe alcohol intake (OR = 3.87, p = 0.005) and deeper depth of the pancreas from the body surface ≥4.2 cm (OR = 0.10, p = 0.002) were associated with the stiffness of the pancreas (>1.40 m/s) [12]. Kuwahara et al. [30] reported that chronic pancreatitis might be diagnosed noninvasively and objectively using SW-EG without performing EUS, the diagnosis accuracy being 77%.

Many reports evaluated the accuracy of EUS elastography for the diagnosis of pancreatic fibrosis. An elastogram in a patient with chronic pancreatitis is displayed in **Figure 4**. Itoh et al. [18] performed EUS elastography preoperatively for the proximal side of the pancreatic tumour and compared the elastograms with microscopic findings of the resected specimens. They found significant correlation between objective parameters assessed by elastography (mean, standard deviation, skewness, kurtosis) and the grade of fibrosis evaluated by histology. Iglesias-Garcia

#### **Figure 4.**

*An elastogram of chronic pancreatitis: heterogeneous soft tissue (green, yellow, and red) corresponding to score 2 in Giovannini classification.*

et al. [31] reported a positive correlation between strain ratio and Rosemont classification (r = 0.813, p < 0.0001).

EUS elastography could predict pancreatic exocrine dysfunction in patients with chronic pancreatitis [32]. Iglesias-Garcia et al. [31] found significant correlation between strain ratio and pancreatic exocrine dysfunction evaluated by 13C-mixed triglyceride breath test.

In autoimmune pancreatitis the specific elastogram detected in five cases was homogenous stiffness of the whole organ, different from the circumscribed mass lesion in ductal adenocarcinoma [33].

#### **8. Prediction of pancreatic fistula after pancreatic surgery**

There are studies reporting that the stiffness of the pancreas measured preoperatively could predict the incidence of postoperative pancreatic juice fistula [34–36]. The postoperative fistula was observed more frequently in patients with lower stiffness of the pancreas (SWV < 1.54 m/s) than in patients with higher stiffness of the pancreas (63 vs. 17%, p < 0.001) [34].

#### **9. Conclusions**

The aim of pancreatic elastography for the pancreas is to reflect accurately the histological structure. The pancreatic elastography is challenging, as the access to this small organ is not easy, deep in the centre of the body. Also the biopsy specimens are difficult to obtain for direct comparison. Many of the challenges were resolved by the new technical achievements in the recent years. Both transabdominal US and EUS elastography might offer the clinicians an important tool for depiction of early chronic pancreatitis and a reliable tool for differential diagnosis between malignant and benign pancreatic masses.

**121**

**Author details**

Iuliu Hatieganu University of Medicine and Pharmacy, Regional Institute of

© 2019 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium,

Gastroenterology and Hepatology, Cluj-Napoca, Romania

\*Address all correspondence to: ciobanulidia@yahoo.com

provided the original work is properly cited.

Lidia Ciobanu

*Pancreatic Elastography*

*DOI: http://dx.doi.org/10.5772/intechopen.89965*

*Pancreatic Elastography DOI: http://dx.doi.org/10.5772/intechopen.89965*

*Ultrasound Elastography*

sification (r = 0.813, p < 0.0001).

lesion in ductal adenocarcinoma [33].

the pancreas (63 vs. 17%, p < 0.001) [34].

between malignant and benign pancreatic masses.

triglyceride breath test.

*2 in Giovannini classification.*

**Figure 4.**

**9. Conclusions**

et al. [31] reported a positive correlation between strain ratio and Rosemont clas-

*An elastogram of chronic pancreatitis: heterogeneous soft tissue (green, yellow, and red) corresponding to score* 

EUS elastography could predict pancreatic exocrine dysfunction in patients with chronic pancreatitis [32]. Iglesias-Garcia et al. [31] found significant correlation between strain ratio and pancreatic exocrine dysfunction evaluated by 13C-mixed

In autoimmune pancreatitis the specific elastogram detected in five cases was homogenous stiffness of the whole organ, different from the circumscribed mass

There are studies reporting that the stiffness of the pancreas measured preoperatively could predict the incidence of postoperative pancreatic juice fistula [34–36]. The postoperative fistula was observed more frequently in patients with lower stiffness of the pancreas (SWV < 1.54 m/s) than in patients with higher stiffness of

The aim of pancreatic elastography for the pancreas is to reflect accurately the histological structure. The pancreatic elastography is challenging, as the access to this small organ is not easy, deep in the centre of the body. Also the biopsy specimens are difficult to obtain for direct comparison. Many of the challenges were resolved by the new technical achievements in the recent years. Both transabdominal US and EUS elastography might offer the clinicians an important tool for depiction of early chronic pancreatitis and a reliable tool for differential diagnosis

**8. Prediction of pancreatic fistula after pancreatic surgery**

**120**

### **Author details**

Lidia Ciobanu Iuliu Hatieganu University of Medicine and Pharmacy, Regional Institute of Gastroenterology and Hepatology, Cluj-Napoca, Romania

\*Address all correspondence to: ciobanulidia@yahoo.com

© 2019 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

### **References**

[1] Kawada N, Tanaka S. Elastography for the pancreas: Current status and future perspective. World Journal of Gastroenterology. 14 Apr 2016;**22**(14):3712-3724

[2] Hirooka Y, Kuwahara T, Irisawa A, Itokawa F, Uchida H, Sasahira N, et al. JSUM ultrasound elastography practice guidelines: Pancreas. Journal of Medical Ultrasonics (2001). 2015;**42**:151-174. DOI: 10.1007/s10396-014-0571-7

[3] Shiina T, Doyley MM, Bamber JC. Strain imaging using combined RF and envelope autocorrelation processing. In: Proceeding of the 1996 IEEE Int Ultrasonics Symposium. San Antonio: IEEE; 1996. DOI: 10.1109/ ULTSYM.1996.584292

[4] Shiina T, Yamakawa M, Nitta N. Recent prognosis of ultrasound elasticity imaging technology. International Congress Series. 2004;**1274**:59-63. DOI: 10.1016/j.ics.2004.07.054

[5] Hirooka Y, Itoh A, Hashimoto S. Utility of EIS: Elastography in the diagnosis of pancreatic diseases. Gastrointestinal Endoscopy. 2005;**61**:AB282. DOI: 10.1016/ S0016-5107(05)01447-1

[6] Uchida H, Hirooka Y, Ito A, Hashimoto S, Kawashima H, Hara K, et al. Utility of elastography in the diagnosis of pancreatic diseases using transabdominal ultrasonography. Gastroenterology. 2005;**128**:A536

[7] Uchida H, Hirooka Y, Itoh A, Kawashima H, Hara K, Nonogaki K, et al. Feasibility of tissue elastography using transcutaneous ultrasonography for the diagnosis of pancreatic diseases. Pancreas. 2009;**38**:17-22. DOI: 10.1097/ MPA.0b013e318184db78

[8] Kawada N, Tanaka S, Uehara H, Takakura R, Katayama K, Fukuda J, et al. Feasibility of second-generation transabdominal ultrasoundelastography to evaluate solid pancreatic tumors: Preliminary report of 36 cases. Pancreas. 2012;**41**:978-980. DOI: 10.1097/MPA.0b013e3182499b84

[9] Itokawa F, Itoi T, Sofuni A, Kurihara T, Tsuchiya T, Ishii K, et al. EUS elastography combined with the strain ratio of tissue elasticity for diagnosis of solid pancreatic masses. Journal of Gastroenterology. 2011;**46**:843-853. DOI: 10.1007/ s00535-011-0399-5

[10] Iglesias-Garcia J, Larino-Noia J, Abdulkader I, Forteza J, Dominguez-Munoz JE. Quantitative endoscopic ultrasound elastography: An accurate method for the differentiation of solid pancreatic masses. Gastroenterology. 2010;**139**:1172-1180. DOI: 10.1053/j. gastro.2010.06.059

[11] Dawwas MF, Taha H, Leeds JS, Nayar MK, Oppong KW. Diagnostic accuracy of quantitative EUS elastography for discriminating malignant from benign solid pancreatic masses: A prospective, single-center study. Gastrointestinal Endoscopy. 2012;**76**:953-961. DOI: 10.1016/j. gie.2012.05.034

[12] Kawada N, Tanaka S, Uehara H, et al. Potential use of point shear wave elastography for the pancreas: A single center prospective study. European Journal of Radiology. 2014;**83**:620-624

[13] Herman BA, Harris GR. Models and regulatory considerations for transient temperature rise during diagnostic ultrasound pulses. Ultrasound in Medicine & Biology. 2002;**28**:1217-1224

[14] Barnett SB, Duck F, Ziskin M. Recommendations on the safe use of ultrasound contrast agents. Ultrasound in Medicine & Biology. 2007;**33**:173-174

**123**

*Pancreatic Elastography*

Journal of Roentgenology.

2011;**197**:532-536

wjg.15.1587

Pancreas. 2010;**39**:1334

*DOI: http://dx.doi.org/10.5772/intechopen.89965*

sonoelastography performed during EUS, used in the differential diagnosis of focal pancreatic masses (with videos). Gastrointestinal Endoscopy.

[23] Zaro R, Lupsor-Platon M, Cheviet A, Badea R. The pursuit of normal reference values of pancreas stiffness by using acoustic radiation force impulse (ARFI)

elastography. Medical Ultrasonography.

[24] Chantarojanasiri T, Hirooka Y, Kawashima H, Ohno E, Sugimoto H, Hayashi D, et al. Age-related changes in pancreatic elasticity: When should we be concerned about their effect on strain elastography? Ultrasonics.

[25] Zaro R, Dina L, Pojoga C, Vesa S, Badea R. Evaluation of the pancreatic tumors by transabdominal shear wave elastography: Preliminary results of a pilot study. Medical Ultrasonography.

[26] Mei M, Ni J, Liu D, et al. EUS elastography for diagnosis of solid pancreatic masses: A meta-analysis.

[27] Pei Q, Zou X, Zhang X, et al. Diagnostic value of EUS elastography in differentiation of benign and malignant solid pancreatic masses: A meta-analysis. Pancreatology.

[28] Popescu A, Săftoiu A. Can elastography replace fine needle aspiration? Endosc Ultrasound.

[29] Yashima Y, Sasahira N, Isayama H, Kogure H, Ikeda H, Hirano K, et al. Acoustic radiation force impulse

elastography for noninvasive assessment of chronic pancreatitis. Journal of

Gastrointestinal Endoscopy.

2010;**72**:739-747

2016;**18**(4):425-430

2016;**69**:90-96

2018;**20**(3):285-291

2013;**77**:578-589

2012;**12**:402-408

2014;**3**:109-117. DOI: 10.4103/2303-9027.123009

[15] Arda K, Ciledag N, Aktas E, et al. Quantitative assessment of normal soft-tissue elasticity using shear-wave ultrasound elastography. AJR. American

[16] Giovannini M, Thomas B, Erwan B, Christian P, Fabrice C, Benjamin E, et al. Endoscopic ultrasound elastography for evaluation of lymph nodes and pancreatic masses: A multicentre study. World Journal of Gastroenterology. 2009;**15**:1587-1593. DOI: 10.3748/

[17] Mayerle J, Simon P, Dickson EJ, et al. The role of EUS guided elastography to diagnose solid pancreatic mass lesions.

[18] Itoh Y, Itoh A, Kawashima H, et al. Quantitative analysis of diagnosing pancreatic fibrosis using EUSelastography (comparison with surgical specimens). Journal of Gastroenterology. 2014;**49**:1183-1192

[19] Janssen J, Papavassiliou I. Effect

[20] Saftoiu A, Vilmann P, Gorunescu F, et al. Accuracy of endoscopic ultrasound elastography used for differential diagnosis of focal pancreatic masses: A multicenter study. Endoscopy.

[21] Saftoiu A, Vilman P, Gorunescu F, et al. Neural network analysis of

dynamic sequences of EUS elastography used for the differential diagnosis of chronic pancreatitis and pancreatic cancer. Gastrointestinal Endoscopy.

[22] Saftoiu A, Iordache S, Gheonea DI, et al. Combined contrast-enhanced power doppler and real-time

of aging and diffuse chronic pancreatitis on pancreas elasticity evaluated using semiquantitative EUS elastography. Ultraschall in der Medizin.

2014;**35**:253-258

2011;**43**:596-603

2008;**68**:1086-1094

*Pancreatic Elastography DOI: http://dx.doi.org/10.5772/intechopen.89965*

[15] Arda K, Ciledag N, Aktas E, et al. Quantitative assessment of normal soft-tissue elasticity using shear-wave ultrasound elastography. AJR. American Journal of Roentgenology. 2011;**197**:532-536

[16] Giovannini M, Thomas B, Erwan B, Christian P, Fabrice C, Benjamin E, et al. Endoscopic ultrasound elastography for evaluation of lymph nodes and pancreatic masses: A multicentre study. World Journal of Gastroenterology. 2009;**15**:1587-1593. DOI: 10.3748/ wjg.15.1587

[17] Mayerle J, Simon P, Dickson EJ, et al. The role of EUS guided elastography to diagnose solid pancreatic mass lesions. Pancreas. 2010;**39**:1334

[18] Itoh Y, Itoh A, Kawashima H, et al. Quantitative analysis of diagnosing pancreatic fibrosis using EUSelastography (comparison with surgical specimens). Journal of Gastroenterology. 2014;**49**:1183-1192

[19] Janssen J, Papavassiliou I. Effect of aging and diffuse chronic pancreatitis on pancreas elasticity evaluated using semiquantitative EUS elastography. Ultraschall in der Medizin. 2014;**35**:253-258

[20] Saftoiu A, Vilmann P, Gorunescu F, et al. Accuracy of endoscopic ultrasound elastography used for differential diagnosis of focal pancreatic masses: A multicenter study. Endoscopy. 2011;**43**:596-603

[21] Saftoiu A, Vilman P, Gorunescu F, et al. Neural network analysis of dynamic sequences of EUS elastography used for the differential diagnosis of chronic pancreatitis and pancreatic cancer. Gastrointestinal Endoscopy. 2008;**68**:1086-1094

[22] Saftoiu A, Iordache S, Gheonea DI, et al. Combined contrast-enhanced power doppler and real-time

sonoelastography performed during EUS, used in the differential diagnosis of focal pancreatic masses (with videos). Gastrointestinal Endoscopy. 2010;**72**:739-747

[23] Zaro R, Lupsor-Platon M, Cheviet A, Badea R. The pursuit of normal reference values of pancreas stiffness by using acoustic radiation force impulse (ARFI) elastography. Medical Ultrasonography. 2016;**18**(4):425-430

[24] Chantarojanasiri T, Hirooka Y, Kawashima H, Ohno E, Sugimoto H, Hayashi D, et al. Age-related changes in pancreatic elasticity: When should we be concerned about their effect on strain elastography? Ultrasonics. 2016;**69**:90-96

[25] Zaro R, Dina L, Pojoga C, Vesa S, Badea R. Evaluation of the pancreatic tumors by transabdominal shear wave elastography: Preliminary results of a pilot study. Medical Ultrasonography. 2018;**20**(3):285-291

[26] Mei M, Ni J, Liu D, et al. EUS elastography for diagnosis of solid pancreatic masses: A meta-analysis. Gastrointestinal Endoscopy. 2013;**77**:578-589

[27] Pei Q, Zou X, Zhang X, et al. Diagnostic value of EUS elastography in differentiation of benign and malignant solid pancreatic masses: A meta-analysis. Pancreatology. 2012;**12**:402-408

[28] Popescu A, Săftoiu A. Can elastography replace fine needle aspiration? Endosc Ultrasound. 2014;**3**:109-117. DOI: 10.4103/2303-9027.123009

[29] Yashima Y, Sasahira N, Isayama H, Kogure H, Ikeda H, Hirano K, et al. Acoustic radiation force impulse elastography for noninvasive assessment of chronic pancreatitis. Journal of

**122**

*Ultrasound Elastography*

**References**

2016;**22**(14):3712-3724

ULTSYM.1996.584292

10.1016/j.ics.2004.07.054

[1] Kawada N, Tanaka S. Elastography for the pancreas: Current status and future perspective. World Journal of Gastroenterology. 14 Apr

transabdominal ultrasound-

tumors: Preliminary report of 36 cases. Pancreas. 2012;**41**:978-980. DOI: 10.1097/MPA.0b013e3182499b84

[9] Itokawa F, Itoi T, Sofuni A, Kurihara T, Tsuchiya T, Ishii K, et al. EUS elastography combined with the strain ratio of tissue elasticity for diagnosis of solid pancreatic masses. Journal of Gastroenterology. 2011;**46**:843-853. DOI: 10.1007/

[10] Iglesias-Garcia J, Larino-Noia J, Abdulkader I, Forteza J, Dominguez-Munoz JE. Quantitative endoscopic ultrasound elastography: An accurate method for the differentiation of solid pancreatic masses. Gastroenterology. 2010;**139**:1172-1180. DOI: 10.1053/j.

[11] Dawwas MF, Taha H, Leeds JS, Nayar MK, Oppong KW. Diagnostic accuracy of quantitative EUS elastography for discriminating

malignant from benign solid pancreatic masses: A prospective, single-center study. Gastrointestinal Endoscopy. 2012;**76**:953-961. DOI: 10.1016/j.

[12] Kawada N, Tanaka S, Uehara H, et al. Potential use of point shear wave elastography for the pancreas: A single center prospective study. European Journal of Radiology. 2014;**83**:620-624

[13] Herman BA, Harris GR. Models and regulatory considerations for transient temperature rise during diagnostic ultrasound pulses. Ultrasound in Medicine & Biology.

[14] Barnett SB, Duck F, Ziskin M. Recommendations on the safe use of ultrasound contrast agents. Ultrasound in Medicine & Biology. 2007;**33**:173-174

s00535-011-0399-5

gastro.2010.06.059

gie.2012.05.034

2002;**28**:1217-1224

elastography to evaluate solid pancreatic

[2] Hirooka Y, Kuwahara T, Irisawa A, Itokawa F, Uchida H, Sasahira N, et al. JSUM ultrasound elastography practice guidelines: Pancreas. Journal of Medical Ultrasonics (2001). 2015;**42**:151-174. DOI: 10.1007/s10396-014-0571-7

[3] Shiina T, Doyley MM, Bamber JC. Strain imaging using combined RF and envelope autocorrelation processing. In: Proceeding of the 1996 IEEE Int Ultrasonics Symposium. San Antonio: IEEE; 1996. DOI: 10.1109/

[4] Shiina T, Yamakawa M, Nitta N. Recent prognosis of ultrasound elasticity imaging technology. International Congress Series. 2004;**1274**:59-63. DOI:

[5] Hirooka Y, Itoh A, Hashimoto S. Utility of EIS: Elastography in the diagnosis of pancreatic diseases. Gastrointestinal Endoscopy. 2005;**61**:AB282. DOI: 10.1016/ S0016-5107(05)01447-1

[6] Uchida H, Hirooka Y, Ito A, Hashimoto S, Kawashima H, Hara K, et al. Utility of elastography in the diagnosis of pancreatic diseases using transabdominal ultrasonography. Gastroenterology. 2005;**128**:A536

[7] Uchida H, Hirooka Y, Itoh A, Kawashima H, Hara K, Nonogaki K, et al. Feasibility of tissue elastography using transcutaneous ultrasonography for the diagnosis of pancreatic diseases. Pancreas. 2009;**38**:17-22. DOI: 10.1097/

[8] Kawada N, Tanaka S, Uehara H, Takakura R, Katayama K, Fukuda J, et al. Feasibility of second-generation

MPA.0b013e318184db78

Gastroenterology. 2012;**47**:427-432. DOI: 10.1007/s00535-011-0491-x

[30] Kuwahara T, Hirooka Y, Kawashima H, Ohno E, Ishikawa T, Yamamura T, et al. Usefulness of shear wave elastography as a quantitative diagnosis of chronic pancreatitis. Journal of Gastroenterology and Hepatology. Mar 2018;**33**(3):756-761

[31] Iglesias-Garcia J, Domínguez-Muñoz JE, Castiñeira-Alvariño M, Luaces-Regueira M, Lariño-Noia J. Quantitative elastography associated with endoscopic ultrasound for the diagnosis of chronic pancreatitis. Endoscopy. 2013;**45**:781-788. DOI: 10.1055/s-0033-1344614

[32] Domínguez-Muñoz JE, Alvarez-Castro A, Lariño-Noia J, Nieto L, Iglesias-García J. Endoscopic ultrasonography of the pancreas as an indirect method to predict pancreatic exocrine insufficiency in patients with chronic pancreatitis. Pancreas. 2012;**41**:724-728. DOI: 10.1097/ MPA.0b013e31823b5978

[33] Dietrich CF, Hirche TO, Ott M, Ignee A. Real-time tissue elastography in the diagnosis of autoimmune pancreatitis. Endoscopy. 2009;**41**:718-720

[34] Harada N, Ishizawa T, Inoue Y, Aoki T, Sakamoto Y, Hasegawa K, et al. Acoustic radiation force impulse imaging of the pancreas for estimation of pathologic fibrosis and risk of postoperative pancreatic fistula. Journal of the American College of Surgeons. 2014;**219**:887-894.e5. DOI: 10.1016/j. jamcollsurg.2014.07.940

[35] Hatano M, Watanabe J, Kushihata F, Tohyama T, Kuroda T, Koizumi M, et al. Quantification of pancreatic stiffness on intraoperative ultrasound elastography and evaluation of its relationship with postoperative pancreatic fistula. International Surgery. 2015;**100**:497-502. DOI: 10.9738/ INTSURG-D-14-00040.1

[36] Lee TK, Kang CM, Park MS, Choi SH, Chung YE, Choi JY, et al. Prediction of postoperative pancreatic fistulas after pancreatectomy: Assessment with acoustic radiation force impulse elastography. Journal of Ultrasound in Medicine. 2014;**33**:781- 786. DOI: 10.7863/ultra.33.5.781

**125**

**Chapter 10**

**Abstract**

Assessment of De Quervain

Tenosynovitis Patients with

Elastography was introduced to clinical practice almost two decades back, to further enhance ultrasound imaging for illustrating the difference in mechanical properties between diseased and healthy tissues, i.e., difference in tissue stiffness, in a qualitative and quantitative way. In the nineteenth century, Fritz De Quervain reported patients with pain and swelling at the wrist. It is an entrapment condition of the tendons within the first extensor compartment. The advantages of ultrasound (U/S), in general, is being a rapid bed-side test, low cost, availability, and great patient compliance all of which elastography makes use of. Elastography imaging for liver fibrosis assessment is a well-known technique; yet recent territories for tissue elasticity assessment are emerging. One of these large territories is muscle tendons elasticity assessment in different pathologic conditions. One of these areas is changes in tendons stiffness. Fifty-two subjects were studied, 30 diseased and 22 healthy. The main complaint of the diseased group was pain at the radial side of the wrist, while healthy subjects were symptom free. Sensitivity was 92%, while specificity was 93%. From my work, I reached the conclusion of that the disease can be diagnosed with strain-based elastography in a quantitative way with confidence and reliability.

**Keywords:** ultrasound, elastography, strain-based elastography, strain elastography,

Elastography was introduced to clinical practice almost two decades back, to further enhance ultrasound imaging [1] and illustrate the difference in mechanical properties between diseased and healthy tissue [2], i.e., difference in tissue stiffness, in a qualitative and quantitative way. The basic idea of elastography is to take advantage of the changed tissue elasticity/stiffness during tissue disease as com-

The advantages of ultrasound (U/S)—in general—is being a rapid bed-side test, low cost, availability, and great patient compliance all of which elastography makes use of. Elastography imaging for liver fibrosis assessment is a well-known technique; yet recent territories for tissue elasticity assessment are emerging. One of these large territories is muscle tendons elasticity assessment in different pathologic condi-

In the nineteenth century, Fritz De Quervain reported patients with pain and swelling at the wrist. It is an entrapment condition (tendon inflammation) of the

Strain-Based Elastography

*Ahmad Mohammad Ghandour*

wrist joint, De Quervain tenosynovitis

pared to adjacent similar normal tissues.

tions. One of these areas is changes in tendons stiffness.

**1. Introduction**

#### **Chapter 10**

*Ultrasound Elastography*

Gastroenterology. 2012;**47**:427-432. DOI: 10.1007/s00535-011-0491-x

2015;**100**:497-502. DOI: 10.9738/ INTSURG-D-14-00040.1

[36] Lee TK, Kang CM, Park MS, Choi SH, Chung YE, Choi JY, et al. Prediction of postoperative pancreatic

fistulas after pancreatectomy: Assessment with acoustic radiation force impulse elastography. Journal of Ultrasound in Medicine. 2014;**33**:781- 786. DOI: 10.7863/ultra.33.5.781

[30] Kuwahara T, Hirooka Y, Kawashima H, Ohno E, Ishikawa T, Yamamura T, et al. Usefulness of shear wave elastography as a quantitative diagnosis of chronic pancreatitis. Journal of Gastroenterology and Hepatology. Mar 2018;**33**(3):756-761

[31] Iglesias-Garcia J, Domínguez-Muñoz JE, Castiñeira-Alvariño M, Luaces-Regueira M, Lariño-Noia J. Quantitative elastography associated with endoscopic ultrasound for the diagnosis of chronic pancreatitis. Endoscopy. 2013;**45**:781-788. DOI:

[32] Domínguez-Muñoz JE, Alvarez-Castro A, Lariño-Noia J, Nieto L, Iglesias-García J. Endoscopic

ultrasonography of the pancreas as an indirect method to predict pancreatic exocrine insufficiency in patients with chronic pancreatitis. Pancreas. 2012;**41**:724-728. DOI: 10.1097/ MPA.0b013e31823b5978

10.1055/s-0033-1344614

[33] Dietrich CF, Hirche TO, Ott M, Ignee A. Real-time tissue elastography in the diagnosis of autoimmune pancreatitis. Endoscopy.

[34] Harada N, Ishizawa T, Inoue Y, Aoki T, Sakamoto Y, Hasegawa K, et al. Acoustic radiation force impulse imaging of the pancreas for estimation of pathologic fibrosis and risk of

postoperative pancreatic fistula. Journal of the American College of Surgeons. 2014;**219**:887-894.e5. DOI: 10.1016/j.

[35] Hatano M, Watanabe J, Kushihata F, Tohyama T, Kuroda T, Koizumi M, et al. Quantification of pancreatic stiffness on intraoperative ultrasound elastography and evaluation of its relationship with postoperative

pancreatic fistula. International Surgery.

2009;**41**:718-720

jamcollsurg.2014.07.940

**124**

## Assessment of De Quervain Tenosynovitis Patients with Strain-Based Elastography

*Ahmad Mohammad Ghandour*

#### **Abstract**

Elastography was introduced to clinical practice almost two decades back, to further enhance ultrasound imaging for illustrating the difference in mechanical properties between diseased and healthy tissues, i.e., difference in tissue stiffness, in a qualitative and quantitative way. In the nineteenth century, Fritz De Quervain reported patients with pain and swelling at the wrist. It is an entrapment condition of the tendons within the first extensor compartment. The advantages of ultrasound (U/S), in general, is being a rapid bed-side test, low cost, availability, and great patient compliance all of which elastography makes use of. Elastography imaging for liver fibrosis assessment is a well-known technique; yet recent territories for tissue elasticity assessment are emerging. One of these large territories is muscle tendons elasticity assessment in different pathologic conditions. One of these areas is changes in tendons stiffness. Fifty-two subjects were studied, 30 diseased and 22 healthy. The main complaint of the diseased group was pain at the radial side of the wrist, while healthy subjects were symptom free. Sensitivity was 92%, while specificity was 93%. From my work, I reached the conclusion of that the disease can be diagnosed with strain-based elastography in a quantitative way with confidence and reliability.

**Keywords:** ultrasound, elastography, strain-based elastography, strain elastography, wrist joint, De Quervain tenosynovitis

#### **1. Introduction**

Elastography was introduced to clinical practice almost two decades back, to further enhance ultrasound imaging [1] and illustrate the difference in mechanical properties between diseased and healthy tissue [2], i.e., difference in tissue stiffness, in a qualitative and quantitative way. The basic idea of elastography is to take advantage of the changed tissue elasticity/stiffness during tissue disease as compared to adjacent similar normal tissues.

The advantages of ultrasound (U/S)—in general—is being a rapid bed-side test, low cost, availability, and great patient compliance all of which elastography makes use of.

Elastography imaging for liver fibrosis assessment is a well-known technique; yet recent territories for tissue elasticity assessment are emerging. One of these large territories is muscle tendons elasticity assessment in different pathologic conditions. One of these areas is changes in tendons stiffness.

In the nineteenth century, Fritz De Quervain reported patients with pain and swelling at the wrist. It is an entrapment condition (tendon inflammation) of the

#### *Ultrasound Elastography*

tendons within the first extensor (dorsal) compartment of the wrist back of the wrist; patients suffered pain during motion of the thumb. The tenosynovitis affects the abductor pollicis longus (APL) and the extensor pollicis brevis (EPB) tendonsmuscle tendons at the back of the wrist [3].

Anatomically, the first extensor compartment of wrist joint is lying between the radial styloid process and the base of the thumb, containing two muscle tendons: the abductor pollicis longus (APL).

De Quervain disease is considered the second most common tendon entrapment condition after trigger finger. Because of repeated trauma, the first dorsal extensor compartment tendons thicken, hindering their gliding through the tight fibro-osseous tunnel.

In B-mode ultrasound scan of the first dorsal compartment, we can find one or more of the following criteria: fluid collection, thickening of tissues, or tissue edema. Colored Doppler application to the tissue under investigation shows increased blood flow to the area.

#### **2. Elastography techniques**

Tissue elasticity is assessed with ultrasound tissue elastography. Elasticity of a tissue is its tendency to resist deformation when applying force the tissue in question, or regaining its original shape after cessation of the force. The idea of elastography is based on assuming that the tissue under examination is entirely elastic and has no viscosity [4].

Two main techniques are developed to measure tissue elasticity quantitatively using ultrasound machines:


#### **3. Strain technique**

Strain technique is first to evolve between the two techniques mentioned above, and it uses two methods for strain calculation: either strain elastography or acoustic radiation force impulse (ARFI). What we are concerned here is about the first method, i.e., strain elastography.

Strain elastography can be achieved by two methods of excitation:


**127**

*Assessment of De Quervain Tenosynovitis Patients with Strain-Based Elastography*

Tsukuba elasticity score is a 1–5 score scale; built upon a map of stiffness of tissues in and around the pathologically affected segment, and the score calculated

a.Lesions scored (1): lesion has less or equal stiffness to surrounding tissues;

c.Lesions scored (3): lesion is stiffer than surrounding tissue, and on elastogram

d.Lesions scored (4): lesion is stiffer than the surrounding tissue, and on elasto-

e.Lesions scored (5): lesion is stiffer than the surrounding tissue, and larger on

My hypothesis was that with the pathological changes in the first extensor compartment tendons of the wrist by virtue of the disease, we could use the Tsukuba score for tissue elasticity [5] to quantitatively assess the elasticity or hardness of the

**6. Ultrasound and strain-based elastography examination technique**

Ultrasound examinations performed using Philips IU22 xMatrix machine (Philips Ultrasound, Bothell, WA, USA) with linear transducer (12–15 MHz).

The patient positioned in sitting at the edge of the examination couch with legs dependent, i.e., both knees flexed at right angle with forearm under examination positioned over the ipsilateral thigh in pronation with a clean plastic sheet in

B-mode ultrasound examination of the compartment retinaculum and tendons performed at the start to scrutinize the full spectrum of the lesion in transverse and

Strain-based elastography was then performed by applying controlled pressure over the compartment guided by colored column on screen of ultrasound machine to achieve the proper pressure amount for strain-based elastography calculation by

Strain-based elastography mean and standard deviation calculations readings

Three strain-based elastography readings are taken for the patient and averaged to calculate the final reading, which will be used to diagnose the

Advanced small parts option and elastography QLAB were used.

based upon the stiffness of the lesion in relation to the surrounding tissues.

b.Lesions scored (2): lesion has mixed areas of stiffness;

has lesser size than B-mode ultrasound;

elastogram than B-mode ultrasound.

between the thigh and forearm of the patient.

The condition is an entrapment syndrome.

**5. Study goal**

affected tendons.

longitudinal views.

are then displayed.

**7. The problem**

the machine.

condition.

gram has same size as B-mode ultrasound; and

*DOI: http://dx.doi.org/10.5772/intechopen.88418*

**4. Tsukuba score for tissue elasticity**

What we are concerned with here is manual compression that is explained in details later on.

### **4. Tsukuba score for tissue elasticity**

Tsukuba elasticity score is a 1–5 score scale; built upon a map of stiffness of tissues in and around the pathologically affected segment, and the score calculated based upon the stiffness of the lesion in relation to the surrounding tissues.

a.Lesions scored (1): lesion has less or equal stiffness to surrounding tissues;


#### **5. Study goal**

*Ultrasound Elastography*

fibro-osseous tunnel.

has no viscosity [4].

using ultrasound machines:

the stress [4].

**3. Strain technique**

strain is calculated [4].

method, i.e., strain elastography.

tures could be studied.

muscle tendons at the back of the wrist [3].

the abductor pollicis longus (APL).

increased blood flow to the area.

**2. Elastography techniques**

tendons within the first extensor (dorsal) compartment of the wrist back of the wrist; patients suffered pain during motion of the thumb. The tenosynovitis affects the abductor pollicis longus (APL) and the extensor pollicis brevis (EPB) tendons-

Anatomically, the first extensor compartment of wrist joint is lying between the radial styloid process and the base of the thumb, containing two muscle tendons:

De Quervain disease is considered the second most common tendon entrapment condition after trigger finger. Because of repeated trauma, the first dorsal extensor compartment tendons thicken, hindering their gliding through the tight

In B-mode ultrasound scan of the first dorsal compartment, we can find one or more of the following criteria: fluid collection, thickening of tissues, or tissue edema. Colored Doppler application to the tissue under investigation shows

Tissue elasticity is assessed with ultrasound tissue elastography. Elasticity of a tissue is its tendency to resist deformation when applying force the tissue in question, or regaining its original shape after cessation of the force. The idea of elastography is based on assuming that the tissue under examination is entirely elastic and

Two main techniques are developed to measure tissue elasticity quantitatively

1.Strain technique: apply normal stress to the tissue and the normal strain of the tissue is calculated; where tissue strain is its ability to expand after removal of

2.Shear-wave technique: a dynamic stress applied to the tissue under examination using different techniques to apply such a dynamic stress, and the tissue

Strain technique is first to evolve between the two techniques mentioned above, and it uses two methods for strain calculation: either strain elastography or acoustic radiation force impulse (ARFI). What we are concerned here is about the first

1.Manual compression by the operator using the ultrasound transducer; pro-

2.No manual compression; where tissue displacement occur physiologically with internal organs as cardiovascular or respiratory systems, hence deeper struc-

What we are concerned with here is manual compression that is explained in

Strain elastography can be achieved by two methods of excitation:

vided that the examined tissue is superficial.

**126**

details later on.

My hypothesis was that with the pathological changes in the first extensor compartment tendons of the wrist by virtue of the disease, we could use the Tsukuba score for tissue elasticity [5] to quantitatively assess the elasticity or hardness of the affected tendons.

#### **6. Ultrasound and strain-based elastography examination technique**

Ultrasound examinations performed using Philips IU22 xMatrix machine (Philips Ultrasound, Bothell, WA, USA) with linear transducer (12–15 MHz). Advanced small parts option and elastography QLAB were used.

The patient positioned in sitting at the edge of the examination couch with legs dependent, i.e., both knees flexed at right angle with forearm under examination positioned over the ipsilateral thigh in pronation with a clean plastic sheet in between the thigh and forearm of the patient.

B-mode ultrasound examination of the compartment retinaculum and tendons performed at the start to scrutinize the full spectrum of the lesion in transverse and longitudinal views.

Strain-based elastography was then performed by applying controlled pressure over the compartment guided by colored column on screen of ultrasound machine to achieve the proper pressure amount for strain-based elastography calculation by the machine.

Strain-based elastography mean and standard deviation calculations readings are then displayed.

Three strain-based elastography readings are taken for the patient and averaged to calculate the final reading, which will be used to diagnose the condition.

#### **7. The problem**

The condition is an entrapment syndrome.

#### **8. Anatomy**

The first extensor compartment of wrist joint is lying between the radial styloid process and the base of the thumb, containing two muscle tendons: the abductor pollicis longus (APL), which is inserted into the base of the first metacarpal bone, or into trapezium bone and extensor pollicis brevis (EPB), which is inserted into the proximal phalanx of the thumb [6].

The APL and EPB muscle tendons with their synovial sheets travel under the extensor retinaculum, which are attached to radial styloid forming tight fibroosseous tunnel.

#### **9. Epidemiology**

De Quervain tenosynovitis is considered the second most common tendon entrapment condition after stenosing tenosynovitis-trigger finger [7].

The condition occurs in middle-aged persons with 3:1 female to male ratio [7].

The condition occurs by the virtue of repetitive wrist movement associated with thumb radial abduction with wrist extension and radial wrist deviation [8].

The classic populations are mothers and childcare workers; however, secretaries and nurses much presented [7, 8]. Other populations affected are golf players or frequent hammer users [9, 10].

Modern life style escalated the incidence of De Quervain tenosynovitis because of computer and cellular phones excessive use [11].

#### **10. Clinical presentation**

Main patient complaint is pain and swelling over the styloid process of the radius [12].

On examination, swelling and tenderness over radial styloid found. Crepitus and triggering may be also found [12].

Finkelstein's test, the clinical test examination, involves flexion of the metacarpophalangeal joint of the thumb in a closed hand followed by ulnar deviation passively of the wrist joint can replicate the pain at radial styloid [9, 12].

#### **11. Pathology**

Because of repeated trauma, the APL and EPB tendons thicken, hindering their gliding through the tight fibro-osseous tunnel [13, 14].

Pathologically, the tendons are thickened by virtue of degenerative changes such as myxoid degeneration, deposition of mucopolysaccharides, and fibrocartilagenous metaplasia [13, 14].

Hence, it is a misnomer to call the condition tenosynovitis, as the pathological changes do not involve tendons inflammation [15].

#### **12. B-mode ultrasound findings**

Several findings could be detected in B-mode ultrasound scan of the first dorsal compartment prior to strain-based elastography application; these findings include [16]:

**129**

**Figure 2.**

**Figure 1.**

*patient with De Quervain tenosynovitis.*

*ultrasound image of a patient with De Quervain tenosynovitis.*

*Assessment of De Quervain Tenosynovitis Patients with Strain-Based Elastography*

• Halo sign; due to edema in the tissues surrounding the tendons.

• Doppler application reveals hyperemia surrounding the tendons.

*Fluid collection in the synovial sheaths of APL and EPB muscle tendons in transverse ultrasound image of a* 

*Thickened synovial sheaths of APL and EPB muscle tendons with fluid collection in tendon sheath in transverse* 

• Thick edematous tendons of APL and EPB (**Figure 3**) at level of styloid process

• Fluid collection in the tendon sheaths (**Figure 1**).

of the radius (compared with contralateral side).

*DOI: http://dx.doi.org/10.5772/intechopen.88418*

• Thickened overlying retinaculum.

• Thickened synovial sheaths (**Figure 2**).

*Assessment of De Quervain Tenosynovitis Patients with Strain-Based Elastography DOI: http://dx.doi.org/10.5772/intechopen.88418*


#### **Figure 1.**

*Ultrasound Elastography*

proximal phalanx of the thumb [6].

frequent hammer users [9, 10].

**10. Clinical presentation**

and triggering may be also found [12].

radius [12].

**11. Pathology**

enous metaplasia [13, 14].

**12. B-mode ultrasound findings**

of computer and cellular phones excessive use [11].

gliding through the tight fibro-osseous tunnel [13, 14].

changes do not involve tendons inflammation [15].

The first extensor compartment of wrist joint is lying between the radial styloid process and the base of the thumb, containing two muscle tendons: the abductor pollicis longus (APL), which is inserted into the base of the first metacarpal bone, or into trapezium bone and extensor pollicis brevis (EPB), which is inserted into the

The APL and EPB muscle tendons with their synovial sheets travel under the extensor retinaculum, which are attached to radial styloid forming tight fibro-

De Quervain tenosynovitis is considered the second most common tendon

The condition occurs in middle-aged persons with 3:1 female to male ratio [7]. The condition occurs by the virtue of repetitive wrist movement associated with

The classic populations are mothers and childcare workers; however, secretaries and nurses much presented [7, 8]. Other populations affected are golf players or

Modern life style escalated the incidence of De Quervain tenosynovitis because

Main patient complaint is pain and swelling over the styloid process of the

On examination, swelling and tenderness over radial styloid found. Crepitus

Finkelstein's test, the clinical test examination, involves flexion of the metacarpophalangeal joint of the thumb in a closed hand followed by ulnar deviation

Because of repeated trauma, the APL and EPB tendons thicken, hindering their

Pathologically, the tendons are thickened by virtue of degenerative changes such

Hence, it is a misnomer to call the condition tenosynovitis, as the pathological

Several findings could be detected in B-mode ultrasound scan of the first dorsal compartment prior to strain-based elastography application; these findings include [16]:

as myxoid degeneration, deposition of mucopolysaccharides, and fibrocartilag-

passively of the wrist joint can replicate the pain at radial styloid [9, 12].

entrapment condition after stenosing tenosynovitis-trigger finger [7].

thumb radial abduction with wrist extension and radial wrist deviation [8].

**8. Anatomy**

osseous tunnel.

**9. Epidemiology**

**128**

*Fluid collection in the synovial sheaths of APL and EPB muscle tendons in transverse ultrasound image of a patient with De Quervain tenosynovitis.*

#### **Figure 2.**

*Thickened synovial sheaths of APL and EPB muscle tendons with fluid collection in tendon sheath in transverse ultrasound image of a patient with De Quervain tenosynovitis.*

#### *Ultrasound Elastography*

#### **Figure 3.**

*Thick edematous tendon of APL muscle in longitudinal ultrasound image of a patient with De Quervain tenosynovitis.*


#### **Table 1.**

*Strain-based elastography indices.*


**Table 2.**

*Strain-based elastography ratios in De Quervain tenosynovitis patients and volunteers.*

#### **13. Current study**

Fifty-two subjects were studied; 30 diseased comprised group 1 and 22 healthy comprised group 2.

The main complaint of the diseased group was pain at the radial side of the wrist with positive Finkelstein test, while healthy subjects were symptom-free with negative Finkelstein test.

There was no significant difference (*p* > 0.01) between groups in regards to age and sex.

Strain-based elastography indices are illustrated in **Table 1**.

The mean elastography value for the diseased was 2.3; while for healthy subjects, it was 6.1 with statistically significant difference between the two groups (*p* < 0.001). For strain ratio details, refer to **Table 2**.

The threshold for diagnosing De Quervain disease was 4.

B-mode ultrasound findings displayed in **Table 2** [3].

#### **14. Discussion**

In De Quervain tendinopathy tendon increased cross section, increased water content of the tendons, abnormal degenerative materials deposited, and changes in collagen fibers properties all lead to changes of the elastic characteristics of the tendons with consequent softening of the affected tendons [17].

**131**

**Author details**

**15. Conclusion**

**Conflict of interest**

Ahmad Mohammad Ghandour

provided the original work is properly cited.

institution, organization, or persons.

Department of Radiology, Faculty of Medicine, Ain Shams University Cairo, Egypt

© 2019 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium,

\*Address all correspondence to: ahmed\_ghandour@med.asu.edu.eg

*Assessment of De Quervain Tenosynovitis Patients with Strain-Based Elastography*

In my work, I found lower sensitivity (92%) than specificity (93%) for the quantitative assessment of the disease, in accordance with the remarks of Sébastien Aubry studying the Achilles tendinopathy with shear-wave elastography [18].

De Zordo et al. [19] stated that normal Achilles tendons show hard consistency as compared to diseased tendons, going with my work results of 6.1 elastography mean value for healthy subjects and 2.3 for diseased. Moreover, Dirrichs et al. [20] studied epicondylar, Achilles, and prepatellar pathologic tendons and found that the diseased tendons returned decreased elastography values as compared to

In my study, I found statistically significant difference (*p* < 0.001) between healthy and diseased subjects in regards to elastography readings in accordance with Chen and coworkers concluding that elastography is an important tool for mechani-

In two healthy subjects, we found low strain ratio, which could be explained by the fact that they were having subclinical tenosynovitis as postulated by De Zordo et al. [22]. Moreover, not possibly to explain the three diseased tendons showing high elastography values except for one patient with cyst formation under the retinaculum

More study is needed for the true benefit of strain-based elastography of the condition comparing the results with histopathological specimens—if possible—of the affected tendons, for a definitive proof of the presence or absence of the disease

We can conclude that the disease can be diagnosed with strain-based elastogra-

The author declares no conflict of interest financially or personally with any

*DOI: http://dx.doi.org/10.5772/intechopen.88418*

healthy volunteers regardless of anatomical location.

cal information assessment of Achilles function [21].

phy in a quantitative way with confidence and reliability.

raising the tension inside the compartment.

and the state of progression of the disease.

#### *Assessment of De Quervain Tenosynovitis Patients with Strain-Based Elastography DOI: http://dx.doi.org/10.5772/intechopen.88418*

In my work, I found lower sensitivity (92%) than specificity (93%) for the quantitative assessment of the disease, in accordance with the remarks of Sébastien Aubry studying the Achilles tendinopathy with shear-wave elastography [18].

De Zordo et al. [19] stated that normal Achilles tendons show hard consistency as compared to diseased tendons, going with my work results of 6.1 elastography mean value for healthy subjects and 2.3 for diseased. Moreover, Dirrichs et al. [20] studied epicondylar, Achilles, and prepatellar pathologic tendons and found that the diseased tendons returned decreased elastography values as compared to healthy volunteers regardless of anatomical location.

In my study, I found statistically significant difference (*p* < 0.001) between healthy and diseased subjects in regards to elastography readings in accordance with Chen and coworkers concluding that elastography is an important tool for mechanical information assessment of Achilles function [21].

In two healthy subjects, we found low strain ratio, which could be explained by the fact that they were having subclinical tenosynovitis as postulated by De Zordo et al. [22].

Moreover, not possibly to explain the three diseased tendons showing high elastography values except for one patient with cyst formation under the retinaculum raising the tension inside the compartment.

More study is needed for the true benefit of strain-based elastography of the condition comparing the results with histopathological specimens—if possible—of the affected tendons, for a definitive proof of the presence or absence of the disease and the state of progression of the disease.

#### **15. Conclusion**

*Ultrasound Elastography*

**13. Current study**

*Strain-based elastography indices.*

comprised group 2.

tive Finkelstein test.

**14. Discussion**

and sex.

**Table 1.**

**Table 2.**

**Figure 3.**

*tenosynovitis.*

Fifty-two subjects were studied; 30 diseased comprised group 1 and 22 healthy

**Index Percentage (%)** PPV 95 NPV 90 Sensitivity 92 Specificity 93

**Number of subjects Strain-based elastography ratio**

28 patients 1–3.5 2 patients 4.2–6 20 volunteers 6.1–9.2 2 volunteers 2–3.9

*Strain-based elastography ratios in De Quervain tenosynovitis patients and volunteers.*

*Thick edematous tendon of APL muscle in longitudinal ultrasound image of a patient with De Quervain* 

The main complaint of the diseased group was pain at the radial side of the wrist with positive Finkelstein test, while healthy subjects were symptom-free with nega-

There was no significant difference (*p* > 0.01) between groups in regards to age

The mean elastography value for the diseased was 2.3; while for healthy subjects, it was 6.1 with statistically significant difference between the two groups

In De Quervain tendinopathy tendon increased cross section, increased water content of the tendons, abnormal degenerative materials deposited, and changes in collagen fibers properties all lead to changes of the elastic characteristics of the

Strain-based elastography indices are illustrated in **Table 1**.

The threshold for diagnosing De Quervain disease was 4. B-mode ultrasound findings displayed in **Table 2** [3].

tendons with consequent softening of the affected tendons [17].

(*p* < 0.001). For strain ratio details, refer to **Table 2**.

**130**

We can conclude that the disease can be diagnosed with strain-based elastography in a quantitative way with confidence and reliability.

#### **Conflict of interest**

The author declares no conflict of interest financially or personally with any institution, organization, or persons.

#### **Author details**

Ahmad Mohammad Ghandour Department of Radiology, Faculty of Medicine, Ain Shams University Cairo, Egypt

\*Address all correspondence to: ahmed\_ghandour@med.asu.edu.eg

© 2019 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/ by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

#### **References**

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[2] Doyley MM, Parker KJ. Elastography: General principles and clinical applications. Ultrasound Clinics. 2014;**9**(1):1-11. DOI: 10.1016/j. cult.2013.09.006

[3] Ghandour AM, Ghandour TM. Strainbased elastography assessment of patients with De Quervain tenosynovitis: A preliminary study. The Egyptian Journal of Radiology and Nuclear Medicine. 2018;**49**:415-418

[4] Sigrist RMS, Liau J, El Kaffas A, Chammas MC, Willmann JK. Ultrasound elastography: Review of techniques and clinical applications. Theranostics. 2017;**7**(5):1303-1329. DOI: 10.7150/thno.18650

[5] Itoh A, Ueno E, Tohno E, Kamma H, Takahashi H, Shiina T, et al. Breast disease: Clinical application of US elastography for diagnosis. Radiology. 2006;**239**:341-350

[6] Hazani R, Engineer NJ, Cooney D, Wilhelmi BJ. Anatomic landmarks for the first dorsal compartment. Eplasty. 2009;**8**:6-11

[7] Zanzoni A. Mint: A molecular interaction database. Journal of Microbiology. 2002;**513**:135-140. DOI: 10.1016/s0014-5793(01)03293-8

[8] Satteson E, Shruti C. Tannan: De Quervain tenosynovitis. In: StatPearls. Treasure Island (FL): StatPearls Publishing; 2019

[9] Ritu G, Abzug Joshua M. De Quervain's tenosynovitis: A review of the rehabilitative options. Hand (N Y). 2015;**10**(1):1-5

[10] Jaworski CA, Krause M, Brown J. Rehabilitation of the wrist and hand following sports injury. Clinics in Sports Medicine. 2010;**29**(1):61-80. DOI: 10.1016/j.csm. 2009.09.007

[11] Ali M, Asim M, Danish SH, et al. Frequency of De Quervain's tenosynovitis and its association with SMS texting. Muscles Ligaments Tendons Journal. 2014;**4**(1):74

[12] Stoller DW, Tirman PF, Bredella MA. Diagnostic imaging, Orthopaedics. Amirsys Inc; 2004. ISBN: 0721629202

[13] Cyriac P-V, van der Windt DAWM, Winters Jan C, Betty M-d J, Cochrane Musculoskeletal Group. Corticosteroid injection for de Quervain's tenosynovitis. Cochrane Database of Systematic Review; 2009. DOI: 10.1002/14651858. CD005616.pub2

[14] Min CJ, Jae-Kyung W, Kyoung-Bun L, In Ae P, Ann Y, Kyung MW. Comparison of shear-wave and strain ultrasound elastography in the differentiation of benign and malignant breast lesions. AJR. 2013;**201**:W347-W356

[15] Clarke MT, Lyall HA, Grant JW, Matthewson MH. The histopathology of de Quervain's disease. Journal of Hand Surgery (British). 1998;**23**(6):732-734

[16] Diop AN, Ba-Diop S, Sane JC, et al. Role of US in the management of de Quervain's tenosynovitis: Review of 22 cases. Journal de Radiologie. 2008;**89** (9 Pt 1):1081-1084

[17] Cortes Daniel H, Suydam Stephen M, Grävare SK, Buchanan Thomas S, Elliott Dawn M. Continuous shear wave elastography: A new method to measure in-vivo viscoelastic properties of tendons. Ultrasound in Medicine & Biology. 2015;**41**(6):1518-1529

**133**

*Assessment of De Quervain Tenosynovitis Patients with Strain-Based Elastography*

*DOI: http://dx.doi.org/10.5772/intechopen.88418*

[18] Sébastien A, Jean-Philippe N, Mickaël T, Fabio B, Chrystelle V, Fabrice M. Viscoelasticity in achilles tendinopathy: Quantitative assessment

by using real-time shear-wave elastography. Radiology. 2015;**274**(3)

AJR. 2009;**193**:W134-W138

2016;**23**(10):1204-1213

[20] Dirrichs T, Quack V, Gatz M, et al. Shear wave elastography (SWE) for the evaluation of patients with tendinopathies. Academic Radiology.

[21] Chen XM, Cui LG, He P, et al. Shear wave elastographic characterization of normal and torn achilles tendons a pilot study. Journal of Ultrasound in Medicine. 2013;**32**(3):449-455

[22] De Zordo T, Chhem R, Smekal V, et al. Real-time sonoelastography: Findings in patients with symptomatic achilles tendons and comparison to healthy volunteers. Ultraschall in der

Medizin. 2010;**31**(4):394-400

[19] Tobias DZ, Christian F, Feuchtner Gudrun M, Vinzenz S, Markus R, Sabine KA. Real-time sonoelastography findings in healthy achilles tendons.

*Assessment of De Quervain Tenosynovitis Patients with Strain-Based Elastography DOI: http://dx.doi.org/10.5772/intechopen.88418*

[18] Sébastien A, Jean-Philippe N, Mickaël T, Fabio B, Chrystelle V, Fabrice M. Viscoelasticity in achilles tendinopathy: Quantitative assessment by using real-time shear-wave elastography. Radiology. 2015;**274**(3)

[19] Tobias DZ, Christian F, Feuchtner Gudrun M, Vinzenz S, Markus R, Sabine KA. Real-time sonoelastography findings in healthy achilles tendons. AJR. 2009;**193**:W134-W138

[20] Dirrichs T, Quack V, Gatz M, et al. Shear wave elastography (SWE) for the evaluation of patients with tendinopathies. Academic Radiology. 2016;**23**(10):1204-1213

[21] Chen XM, Cui LG, He P, et al. Shear wave elastographic characterization of normal and torn achilles tendons a pilot study. Journal of Ultrasound in Medicine. 2013;**32**(3):449-455

[22] De Zordo T, Chhem R, Smekal V, et al. Real-time sonoelastography: Findings in patients with symptomatic achilles tendons and comparison to healthy volunteers. Ultraschall in der Medizin. 2010;**31**(4):394-400

**132**

*Ultrasound Elastography*

**References**

Biology. 1990;**16**:241-246

cult.2013.09.006

10.7150/thno.18650

2006;**239**:341-350

2009;**8**:6-11

Publishing; 2019

2015;**10**(1):1-5

General principles and clinical applications. Ultrasound Clinics. 2014;**9**(1):1-11. DOI: 10.1016/j.

based elastography assessment of patients with De Quervain tenosynovitis: A preliminary study. The Egyptian Journal of Radiology and Nuclear Medicine. 2018;**49**:415-418

[4] Sigrist RMS, Liau J, El Kaffas A, Chammas MC, Willmann JK. Ultrasound elastography: Review of techniques and clinical applications. Theranostics. 2017;**7**(5):1303-1329. DOI:

[5] Itoh A, Ueno E, Tohno E, Kamma H, Takahashi H, Shiina T, et al. Breast disease: Clinical application of US elastography for diagnosis. Radiology.

[6] Hazani R, Engineer NJ, Cooney D, Wilhelmi BJ. Anatomic landmarks for the first dorsal compartment. Eplasty.

[7] Zanzoni A. Mint: A molecular interaction database. Journal of Microbiology. 2002;**513**:135-140. DOI: 10.1016/s0014-5793(01)03293-8

[8] Satteson E, Shruti C. Tannan: De Quervain tenosynovitis. In: StatPearls. Treasure Island (FL): StatPearls

[9] Ritu G, Abzug Joshua M. De Quervain's tenosynovitis: A review of the rehabilitative options. Hand (N Y).

[1] Prker KJ, Huang SR, Musulin RA, Lerner RM. Tissue-response to

mechanical vibrations for sonoelasticity imaging. Ultrasound in Medicine &

[10] Jaworski CA, Krause M, Brown J. Rehabilitation of the wrist and hand following sports injury. Clinics in Sports Medicine. 2010;**29**(1):61-80. DOI:

[11] Ali M, Asim M, Danish SH, et al.

[13] Cyriac P-V, van der Windt DAWM, Winters Jan C, Betty M-d J, Cochrane Musculoskeletal Group. Corticosteroid

10.1016/j.csm. 2009.09.007

Frequency of De Quervain's tenosynovitis and its association with SMS texting. Muscles Ligaments

Tendons Journal. 2014;**4**(1):74

[12] Stoller DW, Tirman PF, Bredella MA. Diagnostic imaging, Orthopaedics. Amirsys Inc; 2004. ISBN:

injection for de Quervain's

[14] Min CJ, Jae-Kyung W, Kyoung-Bun L, In Ae P, Ann Y,

2013;**201**:W347-W356

(9 Pt 1):1081-1084

[17] Cortes Daniel H, Suydam Stephen M, Grävare SK, Buchanan Thomas S, Elliott Dawn M. Continuous

shear wave elastography: A new method to measure in-vivo viscoelastic properties of tendons. Ultrasound in Medicine & Biology.

2015;**41**(6):1518-1529

tenosynovitis. Cochrane Database of Systematic Review; 2009. DOI: 10.1002/14651858. CD005616.pub2

Kyung MW. Comparison of shear-wave and strain ultrasound elastography in the differentiation of benign and malignant breast lesions. AJR.

[15] Clarke MT, Lyall HA, Grant JW, Matthewson MH. The histopathology of de Quervain's disease. Journal of Hand Surgery (British). 1998;**23**(6):732-734

[16] Diop AN, Ba-Diop S, Sane JC, et al. Role of US in the management of de Quervain's tenosynovitis: Review of 22 cases. Journal de Radiologie. 2008;**89**

0721629202

[2] Doyley MM, Parker KJ. Elastography:

[3] Ghandour AM, Ghandour TM. Strain-

### *Edited by Monica Lupsor-Platon*

Elastography, the science of creating noninvasive images of mechanical characteristics of tissues, has been rapidly evolving in recent years. The advantage of this technique resides in the ability to rapidly detect and quantify the changes in the stiffness of soft tissues resulting from specific pathological or physiological processes. Ultrasound elastography is nowadays applied especially on the liver and breast, but the technique has been increasingly used for other tissues including the thyroid, lymph nodes, spleen, pancreas, gastrointestinal tract, kidney, prostate, and the musculoskeletal and vascular systems. This book presents some of the applications of strain and shear-wave ultrasound elastography in hepatic, pancreatic, breast, and musculoskeletal conditions.

Published in London, UK © 2020 IntechOpen © Dr\_Microbe / iStock

Ultrasound Elastography

Ultrasound Elastography

*Edited by Monica Lupsor-Platon*