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PURPOSE To compare characteristics of the vitreomacular interface (VMI) in myopic foveoschisis (mFS) and idiopathic epiretinal membrane foveoschisis (iERM-FS), and to correlate with optical coherence tomography and clinical data. DESIGN Clinicopathological study MATERIALS AND METHODS: Epiretinal membrane and internal limiting membrane (ILM) specimens were removed from eyes with mFS (5 eyes) and iERM-FS (5 eyes). Harvested tissue was processed for immunocytochemistry and prepared by ultrathin series sectioning for transmission electron microscopy. Cell and collagen compositions were compared and correlated with clinical data. RESULTS All eyes presented fibrocellular membranes irrespective if associated with mFS or iERM-FS. Cell and collagen types and distribution on the vitreal side of the ILM were similar in both groups consistent with presence of tractional membranes on OCT images. Immunostaining of all specimens were positive for glial cells, microglia and hyalocytes. Electron microscopy revealed evidence of epiretinal cell multilayers with masses of vitreous collagen and signs of vitreous remodelling in both groups. Three eyes with mFS but none of the eyes with iERM-FS showed massive thinning of the ILM with prominent retinal undulations and presence of retinal nerve fibre layer fragments. CONCLUSION Whereas fibrocellular components of premacular tissue in mFS are similar to iERM-FS, pathologic abnormalities of the ILM were exclusively present in high myopia. Although peeling of the ILM appears important to completely remove tractional components of the VMI, histopathological findings emphasize the risk for retinal damage in these highly myopic eyes indicating that individual preoperative assessment and modification of surgical techniques require further investigation.