MAY 05, 2022
Investigators in the United States used a case series to determine whether using a processed nerve allograft during surgery is a viable technique for corneal neurotization.
This was a retrospective case review of 17 patients aged 4 to 69 years (mean age: 42.6 years) who underwent corneal neurotization with a processed nerve allograft. Donor nerves included ipsilateral or contralateral infraorbital or supraorbital nerves. Coaptation was performed end-to-end or end-to-side. The primary outcome was corneal sensation at final follow-up; other outcomes included best-corrected visual acuity (BCVA) and time to development of corneal sensation.
The etiology of corneal anesthesia was prior infection (8 patients), trigeminal nerve palsy (8 patients), and ocular trauma (1 patient). The mean preoperative Cochet-Bonnet esthesiometry was 0.36 cm, which improved to 4.42 cm postoperatively. Mean time to first gain of corneal sensation was 3.7 months. There were no statistically significant differences in outcome measures when comparing end-to-end vs. end-to-side coaptation and supraorbital vs. infraorbital and ipsilateral vs. contralateral nerve sites. There also was no statistically significant difference between pre- and postoperative BCVA.
The small number of patients in this study makes it difficult to determine if there is truly a difference between the donor nerve sites used and the coaptation method used. In addition, multiple surgeons performed the procedure, with no uniformity for the specific technique. Ideally, a prospective randomized trial employing a uniform technique could help determine any differences.
Corneal neurotization is showing promise in the treatment of neurotrophic keratopathy. This study confirms this promise and demonstrates that the use of a processed nerve allograft is effective, which obviates the harvesting of the patient’s own sural nerve. The median time for patients to attain first sensation was 3.7 months and maximum sensation was achieved in about 6 months. Although there was no difference in pre- and postoperative BCVA, the ocular surface in these patients was significantly improved.