Question

The trabecular meshwork of the eye is composed of which of the following components? (Select all that apply)

• A. Uveal meshwork
• B. Corneoscleral meshwork
• C. Juxtacanalicular (pericanalicular) meshwork
• D. Canal of Schlemm

Hint:

Three layers of trabecular meshwork; Schlemm canal is a downstream channel, not part of the mesh.

Answer 1

The Correct Option is A, B, C

Step 1: Recall the structure of the trabecular meshwork.
The trabecular meshwork (TM) is a sieve-like structure located in the anterior chamber angle (at the iridocorneal junction). It is the principal route of conventional aqueous humour outflow, draining aqueous toward the canal of Schlemm.

Step 2: Identify the three classic layers of the TM.
From inside (anterior chamber) outward, the TM has three histological parts:
1. Uveal meshwork - the innermost portion, adjacent to the anterior chamber, with large irregular spaces.
2. Corneoscleral meshwork - the middle and largest portion, extending from the scleral spur to the anterior wall of the scleral sulcus.
3. Juxtacanalicular (pericanalicular / cribriform) meshwork - the outermost portion lying immediately adjacent to the inner wall of Schlemm canal; this offers the greatest resistance to aqueous outflow.

Step 3: Evaluate each option.
• Uveal meshwork - correct, it is the innermost layer.
• Corneoscleral meshwork - correct, it is the middle layer (note: the recall “uveo-scleral mesh” is a typo for this layer; the uveoscleral pathway is a separate outflow route, but the meshwork layer meant is the corneoscleral mesh).
• Juxtacanalicular/pericanalicular meshwork - correct, outermost layer.
• Canal of Schlemm - this is the collecting channel that receives aqueous after it passes through the TM; it is NOT a part of the meshwork itself.

Step 4: Key fact.
The trabecular meshwork has three layers - uveal, corneoscleral and juxtacanalicular - while the canal of Schlemm is a separate downstream structure.