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What is Earliest field defect in primary open angle glaucoma: and explain in detail?
Ans. is 'b' i.e. Scotoma in Bjerrum's field Visual field defects in Glaucoma:Baring of blind spotScotoma in Bjerrum's fieldArcuate scotomaSeidel's scotomaRing or double arcuate scotoma.Roenne's central nasal step.Advanced field defect:At the last only a small island of central vision {tubular vision) and an accompanying temporal island are left.The temporal island is usually extinguished before the central island although occasionally this sequence is reversed.