Indirect Corneal Neurotization Using the Infraorbital Nerve and Sural Nerve Interposition Graft

Neurotrophic keratopathy (NK) is a sight-threatening condition affecting the corneal innervation and epithelial surface of the cornea. Presently, the only curative treatment is corneal neurotization. The literature favours the supratrochlear nerve and/or supraorbital nerve as the donor nerves selected for neurotization, due to being easily accessed through brow or upper eyelid skin incisions. The infraorbital nerve (ION) is minimally discussed in the literature as it is thought to be a difficult dissection; however, it has the advantage of access through a subpalpebral incision, which does not leave a visible scar. In this case report, indirect corneal neurotization is performed using the ION and a sural nerve interposition graft to reinnervate a cornea diagnosed with NK.

The patient is a 74-year-old female who presents with 6 days of decreased visual acuity. Examination reveals a large corneal ulcer and absent inferior corneal sensation. She is deemed appropriate for corneal neurotization. The patient undergoes an end-to-side neurorrhaphy between the proximal ION within the infraorbital canal and the corneal limbus using an interpositional sural nerve graft. Surgical access was done with relative ease through a subpalpebral incision and an inferior orbitotomy.

Postoperatively, the patient had marked improvement in their corneal sensation, visual acuity, and complete healing of the corneal ulcer. Improvement was noted at 1 month and stabilized by 6 months. By 6 months, the patient had regained sensation in the ION dermatome.

A case of corneal neurotization using the proximal ION is demonstrated, using the end-to-side technique with an interpositional sural nerve graft. The patient had excellent results of her visual acuity, corneal epithelial surface and sensation, with no complications. The authors hope to provide evidence for the use of the proximal ION for corneal neurotization, as it provides sufficient axons, acceptable cosmesis and closer proximity to an inferior corneal ulcer.