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What is Von herick's angle grade 3 of anterior chamber denotes and explain in detail?
Von Herick's technique compares the depth of peripheral anterior chamber with the corneal thickness. The method involves a narrow slit of light from a slit lamp being projected on to the peripheral cornea at an angle of 60deg as near as possible to the limbus. Ratio Angle closure Angle grade 1:1 open angle VH grade 4 1:1/2 Moderately open angle VH grade 3 1: 1/4 Moderately narrow angle VH grade 2 1: <1/4 angle closure likely VH grade 1