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What is All of the following are features of central retinal aery occlusion except and explain in detail?
Central retinal aery occlusion (CRAO) It occurs due to obstruction at the level of lamina cribrosa. clinical features: Symptoms: Patient complains of sudden painless loss of vision. Signs: Direct pupillary light reflex is absent. On ophthalmoscopic examination retinal aeries are markedly narrowed but retinal veins look almost normal. Retina becomes milky white due to oedema. Central pa of the macular area shows cherry-red spot due to vascular choroid shining through the thin retina of this region. Blood column within the retinal veins is segmented (cattle- trucking). After a few weeks the oedema subsides, and atrophic changes occur which include grossly attenuated thread-like aeries and consecutive optic atrophy. Ref:- A K KHURANA; pg num:-255