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What is Lamina cribrosa is absent in - and explain in detail?
The nerve fibers forming the optic nerve exit the eye posteriorly through a hole in the sclera that is occupied by a mesh-like structure called the lamina cribrosa. It is formed by a multilayered network of collagen fibers that inse into the scleral canal wall. It is absent in morning glory syndrome. Ref khurana 6/e