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What is A patient is taking drugs for rheumatoid ahritis and has a history of cataract surgery 1 year back, the patient presented with sudden painless loss of vision, probable diagnosis is? and explain in detail?
Patient of rheumatoid ahritis are given hydroxychloroquine which cause painless loss of vision due to bull's eye maculopathy characterized by a foveolar island of pigment surrounded by a depigmented zone of RPE atrophy, which is itself encircled by a hyperpigmented ring (A). There is moderate to severe reduction in VA (6/36-6/60). A more substantial macular lesion follows, with widespread RPE atrophy surrounding the fovea (B). Later retinal aerioles may become attenuated, and pigment clumps can form in the peripheral retina.(C)