A Deep Defect Over the Temporal Branch and a Question of Flap Choice
A 70-year-old woman undergoes Mohs surgery for a 2.5 cm recurrent basal cell carcinoma of the left temple. Clearance requires three stages; the final defect is 3.5 x 3.0 cm, extends to the deep temporal fascia, and lies over the course of the temporal branch of the facial nerve. She has a history of heavy smoking (1 pack/day) and poorly controlled diabetes (HbA1c 9.2%). She asks for "the best cosmetic result" and wants a flap rather than a graft.
1. How does the anatomy of the temporal region influence your reconstructive options?
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The temporal branch of the facial nerve runs within the superficial temporal fascia (temporoparietal fascia) and crosses the zygomatic arch; dissection deep to the superficial musculoaponeurotic system in this region risks injury and frontalis palsy. A defect extending to the deep temporal fascia means the superficial fascia and nerve may be exposed or involved, so flap elevation must be planned in a plane that protects the nerve - typically superficial to the superficial temporal fascia for local flaps, or use of a flap whose pedicle avoids the nerve course. Options: (1) local transposition/rotation flap (e.g., cervicofacial or rhomboid) elevated in the subcutaneous plane superficial to the nerve; (2) full-thickness skin graft - reliable, but poorer color match and contour on a concave temple; (3) tissue expansion if adjacent skin is adequate; (4) free flap for very large defects (unlikely here). Given her smoking and diabetes, flap viability is a concern; a graft may be safer. If a flap is chosen, design to avoid tension and nerve injury, and consider delaying repair. Document nerve status before and after.
2. Given her comorbidities, how do you weigh flap versus graft, and what preoperative optimization and counseling do you provide?
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Weigh risk of flap failure (smoking, HbA1c 9.2%, diabetes impair wound healing and increase infection and necrosis) against cosmetic outcome. A graft is lower-risk and reliable over a fascial bed but may leave a contour/color mismatch; a local flap offers better match but higher risk of tip necrosis, dehiscence, and infection in a smoker with poor glycemic control. Reasonable approach: (1) optimize - counsel smoking cessation (even 4 weeks pre-op reduces complications), coordinate with primary care to improve glycemic control, consider delaying elective repair until HbA1c improves if feasible; (2) choose a robust option - a well-vascularized local flap with a broad pedicle, or a graft if risk is prohibitive; avoid thin random flaps; (3) technique - tension-free closure, meticulous hemostasis, consider antibiotic prophylaxis, and close follow-up; (4) counsel on realistic expectations, risk of revision, and the possibility of a second-stage procedure. Document the shared decision, the risks discussed, and the plan for glycemic and smoking optimization.