During gonioscopy, the examiner identifies a structure that is the most anterior landmark of the drainage angle. It appears as a fine, pigmented or non-pigmented line that marks the functional limit of the corneal endothelium. This structure is:

• A Trabecular meshwork
• B Scleral spur
• C Schwalbe's line ✓
• D Schlemm's canal

Explanation

Schwalbe's line is the most anterior gonioscopically visible landmark, representing the peripheral termination of Descemet's membrane and the anterior border of the trabecular meshwork. It appears as a glistening white or lightly pigmented line. When anteriorly displaced (Axenfeld's anomaly) or with pigment deposits on it (Sampaolesi's line in pigmentary glaucoma/pseudoexfoliation), it has clinical significance. The trabecular meshwork lies posterior to Schwalbe's line, the scleral spur is the white line demarcating the posterior trabecular meshwork, and Schlemm's canal lies within the sclera and is not directly visible gonioscopically.

Reference: Khurana Comprehensive Ophthalmology, 7th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.