Chemotherapy-induced isolated right pan-retinal atrophy

Abstract

INTRODUCTION
Topically applied ocular medications could be sufficiently absorbed to inflict untoward systemic consequences.1-4 Timolol, a non-selective beta blocker is capable of eliciting severe asthmatic attacks in susceptible individuals. Timolol absorption is via nasal mucosa to systemic circulation. On another hand, systemically administered medications could through ophthalmic and ciliary arteries reach ocular tissues to unleash lethal effects. For instance chloroquine and its derivative, hydroxychloroquine sulphate, which have been useful in treating malaria and in larger doses, collagen-vascular disease, cause a cumulative dose-related pigmentary retinopathy.5,6 Mechanisms of action include inhibition of critical enzymes and interference with the metabolic functions of Retinal Pigment Epithelium (RPE) and photoreceptors. Both drugs apparently have a selective affinity for melanin, so they get concentrated in RPE and uveal tissue and are retained for long periods, even after their usage is stopped.