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What is In POAG (primary open angle glaucoma) which is not seen – a) Horizontal cuppingb) Bayoneting sign (crossing of vessels)c) Macular oedemad) Dot sign and explain in detail?
Glaucomatous changes in optic disc


Early glaucomatous changes :- i) Vertically oval cup; ii)Assymmetry of cup; iii) Large cup with cup : disc ratio > 0.5 (normal 0.3 - 0.4); iv) Splinter hemorrhages; v) Pollar area on disc; vi) Atrophy of retinal nerve fibre layer.
Late glaucomatous changes :- i) Marked cupping (cup : disc ratio 0.7 to 0.9); ii) Thinning of neuroretinal rim; iii) Nasal shifting of retinal vessels with broken appearance at margin (Bayonetting sign); iv) Pulsation of the retinal arterioles at disc margin (pathognomonic); v) Pores in lamina-cribrosa (lamellar dot sign); vi) Total bean - pot cupping; vii) Total disc pallor.