[Application effects of CT angiography and three-dimensional reconstruction technique in repairing scar around the mouth and chin with expanded forehead axial flap].

Objective: To explore application effects of CT angiography (CTA) and three-dimensional reconstruction technique in repairing scar around the mouth and chin with expanded forehead axial flap. Methods: From June 2013 to October 2017, 9 patients with hyperplastic scar around the mouth and chin after deep burns on face were admitted to our unit. The sizes of scars of patients ranged from 8 cm×7 cm to 13 cm×8 cm. One cylindrical skin soft-tissue dilator with nominal volume of 400 to 500 mL was implanted in forehead area of each patient. Five to six months after the dilator was implanted, scar around the mouth and chin was resected, and the dilator was removed. The secondary wound after scar resection was repaired by expanded forehead axial flap with bilateral superficial temporal vessel pedicles. Three of the nine patients received microstomia diorthosis at the same time. Before the operation, CTA and three-dimensional reconstruction were applied to obtain three-dimensional images of superficial temporal arteries and the branches in the donor site, which could identify the travel, adjacent location, and vascular anastomosis of the above-mentioned vessels to guide flap design. The sizes of flaps of patients ranged from 25 cm×9 cm to 30 cm×8 cm. Two to three weeks after the operation, flap pedicles were cut off, restored, and trimmed. The donor site was sutured directly. Ten to twelve days after the flap repair operation, the flap site received depilation treatment with semiconductor freezing point laser once a month for 4 to 6 times. Results: Flaps of all patients survived well, with no blood circulation disorder. The flaps of three patients were slightly bulky, while they were with natural appearance after flap thinning operation in 3 months post flap repair operation. During follow-up of 6 months to 2 years after the operation, color, texture, and thickness of the flaps were close to normal skin around scars. The appearance of perioral and mental region, and opening function of mouth improved significantly, with no recurrence of scar. Frontotemporal incision was hidden, hair on head grew normally, and reconstructed hairline was natural. Conclusions: Scar around the mouth and chin repaired with expanded forehead axial flap were with good appearance and function in operation area and good shape in donor site. CTA and three-dimensional reconstruction technique can provide clear three-dimensional images of superficial temporal arteries and the branches in expanded forehead axial flaps, which can provide reliable basis for preoperative designing of flap, reduce operative risk, and improve survival rate of flap, thus having clinical application value.