Mohs micrographic surgery (MMS) frequently is used in surgical removal of cancerous cutaneous lesions on cosmetically sensitive areas and anatomically challenging sites, including the ears. The vascular supply of the ear is complex and includes several watershed regions that are susceptible to injury during surgical resection or operative closure.
Case Reports
Patient 1—An 82-year-old woman with a 100-pack-year smoking history and no known history of diabetes mellitus or coronary artery disease presented with a superficial and micronodular basal cell carcinoma (BCC) of the left postauricular skin of approximately 18 months’ duration. Mohs micrographic surgery was performed for lesion removal. The BCC was noted to be deeply penetrating and by the second stage was to the depth of the deep subcutaneous tissue (Figure 1A [inset]). Frozen section histopathology revealed a micronodular and superficial BCC. A 2.1×2.0-cm postoperative defect including the posterior surface of the ear, postauricular sulcus, and postauricular scalp remained. To minimize the area left to heal via secondary intention, partial layered closure was performed by placing four 4-0 polyglactin sutures from the scalp side of the defect on the postauricular skin to the postauricular sulcus (Figure 1A).
The patient presented to the clinic on postoperative day (POD) 4, noting pain and redness since the evening of the surgery on the anterior surface of the ear, specifically the cavum concha. Physical examination revealed that the incision site appeared to be healing as expected, but the cavum concha demonstrated erosions and ecchymosis (Figure 1B). A fluid culture was collected, and the patient was started on doxycycline 100 mg twice daily for 10 days. The patient returned to the clinic at POD 10 with skin sloughing and a small border of dark purple discoloration, consistent with early necrosis.
At the 1-month postsurgery follow-up visit, the wound had persistent anterior sloughing and discoloration with adherent debris suggestive of vascular compromise. At the 5-month wound check, the left conchal bowl had a 1-cm through-and-through defect of the concha cavum (Figure 1B [inset]). The favored etiology was occlusion of the posterior auricular artery during the patient’s MMS and reconstruction. Once healed, options including reconstruction, prosthesis, and no treatment were discussed with the patient. The patient decided to pursue partial closure of the defect.
Patient 2—A 71-year-old man with coronary artery disease and no known smoking or diabetes mellitus history presented with a 0.7×0.6-cm cutaneous squamous cell carcinoma of the left helix (Figure 2A [inset]). Mohs micrographic surgery was completed, resulting in a 1.1×1.0-cm defect that extended to the perichondrium. Given the location and size, a linear closure was performed with a deep layer of 5-0 polyglactin sutures and a cutaneous layer of 6-0 polypropylene sutures. The final closure length was 2.1 cm (Figure 2A).
On POD 14, the patient presented for suture removal and reported the onset of brown discoloration of the ear on POD 3. Physical examination revealed the left ear appeared dusky around the mid helix with extension onto the antihelix (Figure 2B). Because one of the main concerns was necrosis, a thin layer of nitropaste ointment 2% was prescribed to be applied twice daily to the affected area, in addition to liberal application of petroleum jelly. On POD 21, the left mid helix demonstrated a well-defined area of necrosis on the helical rim extending to the antihelix, and conservative treatment was continued. Four weeks later, the left ear had a prominent eschar, which was debrided. On follow-up 6 weeks later, the area was well healed with an obvious notched defect of the helix and scaphoid fossa (Figure 2B [inset]). The favored etiology was occlusion of the middle helical arcade during the patient’s MMS and reconstruction. Reconstructive options were discussed with the patient; however, he declined any further reconstructive intervention.
Comment
Auricular Vasculature—In our patients, the auricular vascular supply was compromised during routine MMS followed by reconstruction, resulting in tissue necrosis. Given the relative frequency of these procedures and the risk for tissue necrosis, a review of the auricular vasculature with special attention to the conchal bowl and helical rim was warranted (Figure 3).