**4.3 Patients in the two groups were stratified according to whether there was a history of abdominal surgery**

Stratified comparisons were made with or without a history of abdominal surgery. The experimental data were divided into four groups: ① CTA + NAS (non-abdominal surgery); ② CTA + AS; ③ US + NAS; ④ US + AS. The results showed that the time and total operation time of the flap were increased in both the CTA group and the US group in patients with a history of abdominal surgery (*P* < 0.05). For patients with a

**Figure 1.** *Comparison of key intraoperative indicators.*

**Figure 2.** *Comparison of key postoperative indicators.*

*Application of CT Angiography in Delayed DIEP Flap Breast Reconstruction DOI: http://dx.doi.org/10.5772/intechopen.112913*

history of abdominal surgery, the time and total operation time of the flap in the CTA group were lower than those in the US group (*P* < 0.05). For patients with no history of abdominal surgery, the time of flap resection in CTA group was lower than that in US group (*P* < 0.05), and there was no significant difference in total operation time (*P* > 0.05) (**Table 3**).

#### **4.4 Analysis of consistency rate of imaging surgery**

Among 206 flaps in the observation group, the perforator selection in 200 flaps was related to CTA, and the consistency rate of imaging operation was 97.09%; among 92 flaps in the control group, the perforator selection in 40 flaps was related to US, and the consistency rate of imaging operation was 43.48%, with statistical significance (*P* < 0.001) (**Table 4**).

#### **4.5 Typical cases**

The female patient, 65 years old, was admitted to hospital due to "left breast defect 10 years after left breast cancer surgery." Specialized physical examination on admission showed: chest: postoperative changes of left breast cancer, absence of left breast, surgical scar about 15.0×1.0 cm in length visible on left chest wall, good healing, no skin ulceration, nodules and other abnormalities. There was mild drooping of the right breast, no obvious abnormal nodules in it, no obvious enlarged lymph nodes in the bilateral axilla and the upper and lower clavicular region. Abdomen: The patient's abdomen was slightly elevated, and the longitudinal surgical scar about 10.0\*1.0 cm in length was visible in the lower abdomen. Preoperative images are shown in **Figure 3A**. After admission, the general condition assessment was completed, and no obvious contraindications were found, so the left breast reconstruction with DIEP flap was performed under general anesthesia. Before surgery, the patients underwent CTA


*Note: Comparison of perforation anatomy time between different groups: a is* ①*vs*②*comparison; b is* ③*vs*④ *comparison; c is* ①*vs*③ *comparison; d is* ②*vs*④ *comparison. Total operation time (min): e is* ①*vs*②*comparison; f is* ③*vs*④ *comparison; g is*  ①*vs*③ *comparison; and h is* ②*vs*④ *comparison.*

#### **Table 3.**

*Stratification analysis according to the history of abdominal surgery between two groups.*


#### **Table 4.**

*Comparison of the consistency rate of imaging surgery between two groups.*

#### **Figure 3.**

*Preoperative thoracic and abdominal images of the patient. (A) Preoperative image, and (B) In the preoperative positioning image, the black arrow shows the vessel perforator located by CTA, and the red mark in the red circle is the vessel perforator location point evaluated by preoperative ultrasound.*

#### **Figure 4.**

*CTA images of perforator vessels. (A) The left perforator was in the shape direction of the flap, (B) The exit point of the left perforator flap, (C) Vertical distance between sagittal perforating branches and the center of the umbilicus, and (D) Vertical distance between left and right perforating branches and the center of the umbilicus.*

examination first, and then abdominal ultrasound examination. The body surface identification of the dominant perforator was performed in the blind state, respectively, as shown in **Figure 3B**. Before surgery, the location of the dominant perforator on the left and right sides was calculated in horizontal, coronal and sagittal positions with the umbilical level as the center, respectively, as shown in **Figure 4**. During the operation, CTA navigation technology was combined to accurately locate the corresponding perforator vessels, as shown in **Figure 5**. The perforator vessels of both sides of the flap and DIEP flap were completely free for flap shaping and breast shaping, as shown in

*Application of CT Angiography in Delayed DIEP Flap Breast Reconstruction DOI: http://dx.doi.org/10.5772/intechopen.112913*

**Figure 5.**

*Perforator vessel image-real comparison. (A) The red arrow shows the left and right perforations respectively, and (B and C) The actual right and left perforations calculated according to CTA during the operation respectively.*

**Figure 6**. The surgery was successful. The chest drainage tube was removed 3 days after surgery, and the abdominal drainage tube was removed 5 days after surgery.
