The pathogenesis of idiopathic macular holes and cysts is currently debated. The authors studied the histopathologic features of 41 specimens. Of 22 full-thickness holes, 16 (73%) had epiretinal membranes (ERMs), 15 (68%) had cystoid macular edema (CME), and 3 (17%) were sealed by fibroglial and retinal pigment epithelial hyperplasia. Photoreceptors were variably degenerated, for a mean of 480 microns (range, 200-750 microns) from the hole margins. Of 12 lamellar macular holes, 6 (50%) had an ERM exhibiting tangential traction on the internal limiting membrane. Cystoid macular edema was present in five (71%) of seven macular cysts, and an ERM was noted in only one (14%). The authors' results suggest that ERM tangential traction may play a role in the pathogenesis of lamellar macular holes. Macular holes often have associated ERMs and CME, which may be potentially reversible.