[Establishment and application of three-dimensional model of deep inferior epigastric artery perforator flap based on computed tomography angiography]

Objective: To explore the establishment and application of three-dimensional model of deep inferior epigastric artery perforator flap based on computed tomography angiography (CTA). Methods: Six patients with breast absence after modified radical mastectomy because of breast cancer, 5 patients with congenital absence of vagina, and 6 patients with Paget's disease of penis and scrotum were hospitalized in our unit from January 2012 to April 2017. The size of wounds after excision of the lesion or that of flaps needed for reconstruction ranged from 17 cm×5 cm to 25 cm×9 cm. Abdominal CTA was performed before the surgery, and data of CTA were sent to CT workstation to make three-dimensional model of deep inferior epigastric artery perforator flap according to shape and size of wound. The number, course, and location of deep inferior epigastric artery, vein, and their perforators, and the superficial inferior epigastric vein were observed in the above-mentioned three-dimensional model. The rectangular plane coordinate system with the umbilicus as the origin was established to locate and observe course and type of the largest deep inferior epigastric artery perforator in left and right side. Deep inferior epigastric artery perforator flaps were designed and deep inferior epigastric artery perforators etc. were marked according to three-dimensional models of the flaps before the surgery. The condition observed in three-dimensional model of the flap was compared with the clinical condition in the surgery of free transverse bilateral deep inferior epigastric artery perforator flap transplantation for breast reconstruction and longitudinal pedicled thinned unilateral deep inferior epigastric artery perforator flap transplantation for vagina reconstruction and wound repair of Paget's disease of penis or scrotum. The size of flap ranged from 17 cm×6 cm to 25 cm×10 cm. Results: Seventeen three-dimensional models of deep inferior epigastric artery perforator flaps were established, including 6 bilateral models and 11 unilateral models. Seventy-two reliable deep inferior epigastric artery perforators were observed in the three-dimensional model with 3.2±0.7 in the right and 3.1±0.8 in the left. The locations of the largest deep inferior epigastric artery perforators in the right and left were [(-3.2±1.4) cm, (-1.0±0.7) cm] and [(4.0±1.2) cm, (-1.2±1.1) cm] respectively. Fourteen largest deep inferior epigastric artery perforators coursed directly and nine coursed tortuously in the rectus muscle. Twenty-three superficial inferior epigastric veins were detected in the three-dimensional models of the flaps. The number, location, and course of deep inferior epigastric artery and vein and superficial inferior epigastric vein observed in the three-dimensional model of deep inferior epigastric artery perforator flap were in accordance with the condition observed in the surgery. Seventy reliable deep inferior epigastric artery perforators were detected in the surgery, and the other 2 perforators were unclear due to bleeding. Course of these perforators were in accordance with the condition observed in the three-dimensional model. Deep inferior epigastric artery perforator flaps of all patients survived well with no complication except that 1 patient suffered from delayed healing of wound in perineum. During follow-up of 1 to 12 months, all flaps survived with good shape and texture. Conclusions: The three-dimensional model of deep inferior epigastric artery perforator flap based on CTA can be established easily and can provide information of number, location, and course of deep inferior epigastric artery, vein, and their perforators, and superficial inferior epigastric vein to guide preoperative design and intraoperative dissection of the flap effectively.