Healing of the orbital socket after total exenteration can be achieved either by 1) spontaneous granulation, associated with healing by secondary intention, or 2) the use of a flap or a graft. Spontaneous granulation results in a prolonged healing process so it should be avoided, especially in patients with 1) a history of neoadjuvant radiotherapy that can delay the recovery process further, and 2) anticipated adjuvant radiotherapy after surgery. Given that a significant portion of exenteration patients receive neoadjuvant or adjuvant radiotherapy, there has been much research interest in the utility of a flap or graft in facilitating the healing process. In this issue of CJO, Lemaître and colleagues explore the utility of an ipsilateral temporalis muscle flap after total exenteration for ophthalmic tumours.
1- Lemaître S
- Green F
- Dendale R
- Vincent-Salomon A
- Desjardins L
- Cassoux N
- Couturaud B
- Lévy-Gabriel C.
Total orbital exenteration with temporalis muscle transfer and secondary healing.
This was a single centre retrospective study that included all patients who underwent total exenteration for an ophthalmic malignancy with a single stage repair using a temporalis flap between 2009 and 2016. For all patients, after transferring ipsilateral temporalis over to the site of exenteration, the anterior surface of the muscle flap was left to heal by secondary intention. The following data were collected: sex; age; histologic tumor diagnosis; complete or incomplete excision on histology; time to complete epithelialization; data regarding the neoadjuvant and adjuvant orbital external beam radiotherapy; orbital tumor recurrence after exenteration; occurrence of metastases; patient survival; and postoperative complications.
The 29 patients enrolled in the study included: 18 conjunctival melanomas, 2 choroidal melanomas, 6 squamous cell carcinomas, 2 sebaceous cell carcinomas, and 1 basal cell carcinoma. Mean age at surgery was 70.7 years. On histological exam, tumour excision was complete in 25 patients. Of these, 3 had insufficient negative margin and required adjuvant orbital radiotherapy; none had recurrence post radiotherapy. Another 3 patients who had conjunctival melanomas developed local recurrence despite sufficient negative margins. Meanwhile, 4 of the 29 patients had incomplete tumour excision (positive margin). While 3 underwent adjuvant radiotherapy with no subsequent orbital recurrences, radiotherapy was unable to be performed in the fourth patient given his poor general health. Twelve patients had history of neoadjuvant radiotherapy. The mean time to epithelialization was not significantly different (p = 0.25) between the patients who received neoadjuvant radiotherapy (6.2 weeks) versus those who did not (9.2 weeks). Four patients developed post-operative complications: 2 sino-orbital fistulas, 1 flap necrosis with subsequent sino-orbital fistula, and 1 orbital cyst. All patients were fitted with prostheses and were satisfied with aesthetic outcomes.
Previous studies have reported the healing time in exenteration to be between 5 to 11 months with spontaneous granulation, 10 months with a split skin graft, and 6 weeks with dermis fat graft. Lemaitre and colleagues demonstrated that the time to epithelialization is as short as 7.9 weeks with a temporalis flap, markedly shorter than spontaneous granulation and split skin graft. This reduced healing time allows for early postoperative radiotherapy. Given that the adjuvant radiotherapy was indicated in as many as 7 of the 29 (24%) exenteration patients, either due to insufficient or lack of negative margin, the ability to start postoperative radiotherapy as early as possible can reduce the risk for interval growth, local spread, and metastasis of the residual tumor. Another advantage of temporalis muscle flap is reduction in hyperostosis of the socket, which can be misdiagnosed as tumor recurrence or infection. Lastly, temporalis flap reduces the risk for osteoradionecrosis in the patients with history of neoadjuvant radiotherapy, which was given to a significant portion (12/29; 41%) of exenteration patients.
The surgical technique for the temporalis flap used by Lemaître and colleagues is unique compared to the temporalis flaps documented in previous reports. Their technique involves allowing the anterior surface of the muscle flap to heal by secondary intention, as opposed to covering the muscle flap with a cutaneous advancement flap or a skin graft. This novel approach allows for a shorter procedure time and early detection of local tumor recurrence on clinical exam in comparison to the previous temporalis flap techniques; good cosmesis; low rate of complications (only 1/29 with flap necrosis); and all the aforementioned benefits of temporalis flap over spontaneous granulation.
To conclude, this study presents a novel approach to total orbital exenteration with temporalis muscle transfer and secondary healing of the anterior surface of the flap. The surgical technique outlined in this study provides significant benefits and minimal risks when compared to the exenteration techniques utilizing spontaneous granulation, skin graft, and also the temporalis flap from previous reports. Therefore, this paper makes significant contribution to the growing body of literature and the care of patients with aggressive ophthalmic malignancies.