Article

DRY EYE DX AND TX

CORNEAL REHABILITATION FOR A NEUROTROPHIC CORNEA

Neurotrophic keratitis (NK) is considered one of the most challenging anterior segment conditions to manage due to its chronic and visually destructive nature. When intervening, timeliness is of the essence. In some cases, by the time a patient lands in the practitioner’s chair, the cornea may have already sustained serious damage and scarring. NK is a degenerative corneal disease caused by impairment of trigeminal corneal innervation, leading to epithelial breakdown and compromised healing. NK may result in the development of corneal ulceration, melting, and perforation (Bonini et al, 2003). Systemic diseases, such as diabetes or herpetic infections, may be the cause of NK, and corneal injury or surgery may be a trigger (Sacchetti and Lambiase, 2014).

Corneal Rehabilitation

Recently, the U.S. Food and Drug Administration approved cenegermin (Oxervate, Dompé) for the pharmaceutical treatment of NK. Until now, there has been a lack of specific medical intervention, so management was aimed at promoting corneal healing and preventing progression (Sacchetti and Lambiase, 2014). In moderate- to severe-stage NK, amniotic membrane therapy or tarsorrhaphy may be indicated (Sacchetti and Lambiase, 2014).

Scleral lenses have been proposed to offer a protective therapy by acting to shield the cornea from the external environment, promoting healing within a fluid reservoir and providing better visual acuity through a neutralized optic.

A Case of Mysterious NK

The confirmed etiology for a 29-year-old male’s chronic bilateral NK was not clear and was likely multifactorial. After several years of non-continuous care with multiple healthcare providers, he presented to our clinic for low vision services with a history of longstanding uncontrolled Type 1 diabetes, previous ophthalmic topical medication toxicity, and presumed history of herpes simplex virus (HSV). His visual acuity was 1/600 OD and 20/100 OS. Biomicroscopy revealed a significant central ulcer, stromal edema, and diffuse punctate keratitis in the right eye (Figure 1A) and less advanced central erosion with mild stromal haze and keratitis in the left eye. The patient had no signs of active HSV infection in either eye.

Figure 1. Anterior segment photography of stage 3 NK (A); amniotic membrane treatment (B); and three-day post-amniotic membrane therapy (C).

An amniotic membrane was placed on the right eye (Figure 1B), with concurrent administration of preservative-free artificial tears q2h. It was worn for three days before dissolving. Dramatic improvement in the central corneal defect was observed (Figure 1C). The goal of amniotic membrane therapy in this case was to stabilize the ocular surface enough to introduce scleral lens wear as a protective medical device. He was prescribed a topical steroid/antibiotic medication with a plan to continue low-dose, long-term oral anti-viral therapy and appropriate management of diabetes, as directed by his primary care physician.

He was subsequently fit into therapeutic scleral lenses, achieving 20/50 acuity OD and 20/20 acuity OS, with significantly increased comfort. Due to increased risk, he will be monitored frequently. CLS

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