Gonioscopy is useful to see details of which of the following?
High-Yield Explanation
Ans. b (Angle of the anterior chamber) (Ref Basak's ophthalmology 4th/270)The purpose of gonioscopy is to identify abnormal angle structures and to estimate width of chamber angle.Direct (with goniolenses):Provides direct view of angle.Used for diagnostic & operative purposes.Indirect (with gonioprisms):Provides mirror image of opp angle.Can be used only under a slit lamp.# Normal angle structures seen from anterior to posterior:1. Schwalbe's line2. Trabecular meshwork3. Scleral spur4. Ciliary band# Grading of the angle (Schaffer's):GradeAngleGonioscopic ViewClinical interpretationIVWide open (35-45deg)All structures seenClosure improbableIIIOpen (20-35deg)Scleral spur seenClosure improbableIIModerately narrow (10-20deg)Trabecular meshwork seenClosure possibleIExtremely narrow (<10deg)Schwalbe's line visibleClosure imminentOCompletely closed (0deg)Nothing visibleClosure present