Abstract
Abstract: :
Purpose: Although comprehensive differentials for corneal hypoesthesia are readily available, comparable information for manifest neurotropic keratitis (NTK) is surprisingly difficult to identify. The purpose of this report was to document the etiologic spectrum of NTK in a large series of patients. Methods: Charts for all patients treated by one individual (JCA) for NTK within the Loma Linda University Health Care System and the Inland Eye Institute between 7/1/98 and 12/6/01 were reviewed. Eyes sustaining chemical burns, demonstrating active infectious or immune processes, or suffering edema generating endothelial dysfunction were excluded. Clinical definition of NTK was based on the Mackie classification system (Stages I-III), and confirmed by quantitated corneal sensation measurement utilizing the Cochet-Bonnet esthesiometer. Results: One hundred and twelve eyes meeting the inclusion criteria for NTK were identified. In order of decreasing frequency, primary etiologies included; retinal surgery related 20%, topical beta-blocker related 16%, herpes zoster ophthalmicus 15%, essential 15%, herpes simplex keratitis 8%, non-retinal ocular surgery related 5%, contact lens associated 5%, stroke 4%, neurosurgery related 3%, diabetes mellitus 3%, and other 2%. "Other" etiologies included primary amyloidosis (2 eyes) and trauma (1 eye). Thirty-four patients (30%) demonstrated multiple etiologies. Conclusion: Neurotropic keratitis can be generated by a broad spectrum of medical and surgical conditions, with the historically recognized entities of herpes zoster, herpes simplex, and neurosurgery comprising only a limited fraction (26%) of the total. Surprisingly, the previously unrecognized conditions of retinal surgery and beta-blocker related NTK represented the two most common etiologies. Multifactorial generated disease was identified in nearly one third of all cases.