**2.3 Magnetic resonance imaging in hydatid cysts**

MRI is better to show cyst wall defect, biliary and neurological involvement. Cysts are hyperintense on T2W images and are covered by a low signal frame possibly because of the collagen rich pericyst [1]. If available, daughter cysts are hypointense compared to the intracystic fluid on T1 weighted imaging and hyperintense on T2-weighted images [5]. DW MRI makes the differentiation of CE1 hydatid cysts from other simple cysts with their hyperintense image. Apparent diffusion coefficient (ADC) of the hydatid cyst is lower compared to ADC of simple cyst because of internal viscous contents [1]. Also, ADC values of simple cysts and type I to III hydatid cysts are higher than ADC values of abscesses because diffusion of protons throughout thin fluid is limited. ADC values of type IV hydatid cysts and abscesses present no considerable statistical difference [5].

#### **Figure 14.**

*MRI showing hydatid cyst in the liver of a 45 years old male: (A) coronal T1 weighted image, (B) coronal T2 weighted scan and (C) axial T2 weighted scan.*

#### **Figure 15.**

*(A) Axial T2 weighted MRI showing splenic hydatid cyst and (B) coronal T2 weighted scan of hydatid disease in L4-5 vertebra.*

#### **Figure 16.**

*MRI showing hydatid cyst in the lower pole of the kidney: (A) coronal T1 weighted scan and (B) axial T2 weighted scan.*

MRI demonstrates the degree of cyst degeneration with secession of the wall, collapsed membranes are observed as bent linear compositions inside the cyst. Wall calcification is demonstrated better on MRI compared to CT, besides MRI is more successful than CT to represent irregularities of borders that points out inchoative segregation of membranes [5].

MRI is also better to differentiate liver hydatid cysts from other simple cysts [4] (**Figures 14**–**18**).

**73**

**Figure 19.**

**Figure 18.**

**Figure 17.**

cardiac chamber [8] (**Figure 18**).

In cardiac cystic echinococcosis, trans-thoracic echocardiography, CT and MRI can demonstrate the cystic structure of the lesion and it's correlation with the

*CT scan showing intraperitoneal cyst rupture with diffuse peritoneal effusion.*

*(A) CT image of rupture of hydatid cyst in the lung, (B) CT scan of intrabiliary rupture of hydatid cyst. (C)* 

*Case of cardiac cyst hydatid: (A) computed tomographic image, (B) magnetic resonance imaging of transverse* 

*MRI showing hydatid cyst in the cyst hydatid in the mesosalpinx adjacent to the left ovary: (A) axial T2* 

*section, and (C) magnetic resonance imaging of longitudinal section showing daughter cysts.*

*Imaging in Echinococcosis*

*DOI: http://dx.doi.org/10.5772/intechopen.88708*

*weighted image and (B) coronal T2 weighted image.*

#### **Figure 17.**

*Overview on Echinococcosis*

**Figure 14.**

**Figure 15.**

**Figure 16.**

*weighted scan.*

*in L4-5 vertebra.*

*weighted scan and (C) axial T2 weighted scan.*

**72**

segregation of membranes [5].

(**Figures 14**–**18**).

MRI demonstrates the degree of cyst degeneration with secession of the wall, collapsed membranes are observed as bent linear compositions inside the cyst. Wall calcification is demonstrated better on MRI compared to CT, besides MRI is more successful than CT to represent irregularities of borders that points out inchoative

*MRI showing hydatid cyst in the lower pole of the kidney: (A) coronal T1 weighted scan and (B) axial T2* 

*MRI showing hydatid cyst in the liver of a 45 years old male: (A) coronal T1 weighted image, (B) coronal T2* 

*(A) Axial T2 weighted MRI showing splenic hydatid cyst and (B) coronal T2 weighted scan of hydatid disease* 

MRI is also better to differentiate liver hydatid cysts from other simple cysts [4]

*MRI showing hydatid cyst in the cyst hydatid in the mesosalpinx adjacent to the left ovary: (A) axial T2 weighted image and (B) coronal T2 weighted image.*

#### **Figure 18.**

*Case of cardiac cyst hydatid: (A) computed tomographic image, (B) magnetic resonance imaging of transverse section, and (C) magnetic resonance imaging of longitudinal section showing daughter cysts.*

#### **Figure 19.**

*(A) CT image of rupture of hydatid cyst in the lung, (B) CT scan of intrabiliary rupture of hydatid cyst. (C) CT scan showing intraperitoneal cyst rupture with diffuse peritoneal effusion.*

In cardiac cystic echinococcosis, trans-thoracic echocardiography, CT and MRI can demonstrate the cystic structure of the lesion and it's correlation with the cardiac chamber [8] (**Figure 18**).


#### **Table 3.**

*Frequency and location specific complications of hydatid disease [2].*

ERCP and MRCP show cystobiliary relationship, daughter vesicles & germinative membranes of cysts in bile ducts, dilated bile ducts. However, because of high intracystic pressure, communication of cyst with bile ducts can't be shown via ERCP& MRCP effectively [1].
