Which macular hole is described as partial-thickness, or lamellar, not involving the full macular thickness?

• A. Full-thickness macular hole
• B. Lamellar (partial-thickness) hole
• C. Epiretinal membrane
• D. Macular edema

Answer: (B)

This question focuses on how macular holes differ by how much retinal thickness they involve on OCT. The partial-thickness, or lamellar, hole is a foveal defect that does not span all retinal layers—the inner retina shows a break while the outer retina remains intact. This creates a shallow, irregular foveal contour rather than a full-thickness gap. In contrast, a full-thickness macular hole goes from the internal limiting membrane through the entire retinal thickness to the outer retina, producing a complete central hole and more pronounced vision loss. An epiretinal membrane sits on the surface of the retina and distorts vision but does not create a hole through the retinal layers. Macular edema involves thickening and fluid-filled cysts in the retina, not a discrete partial-thickness hole.