Lamellar macular hole formation in patients with diabetic cystoid macular edema.

Purpose: To report lamellar macular hole formation in four patients with diabetic cystoid macular edema (CME).
Methods: A review of the medical records of four patients with diabetic CME in whom lamellar macular hole formation was observed. The morphologic changes of CME, seen using optical coherence tomography (OCT), and best-corrected visual acuity were evaluated.
Results: Lamellar macular hole formation had occurred, as determined by slit-lamp biomicroscopy and OCT. Although the inner retinal layer had disappeared, the outer retinal layer was preserved. On OCT, the reflective line of an epiretinal membrane or a posterior hyaloid membrane was seen on the surface of juxtafoveal retina, and visual acuity remained unchanged in all four patients.
Conclusion: In diabetic patients with CME, the CME occasionally changes spontaneously to a lamellar macular hole. Although the central cystoid space disappears and foveal thickness decreases after this transformation, visual acuity may be little affected as long as the structure of the outer retina remains intact.