The author describes the clinical, autoptical, light microscopical and ultrastructural features of a particular type of retroretinal membrane in four eyes with total rhegmatogenous retinal detachment after severe anterior segment trauma. The membranes originate from defects of the most posterior pars plana at the site of disinsertions or detachments of the ciliary epithelium. From here they spread over parts of the whole posterior face of the detached retina encircling and constricting its folds. These formations are primarily composed of fibrin and secondarily become populated by macrophages, fibroblasts, pigment epithelial cells, as well as fibrous astrocytes, and finally are organized. The significance of such membranes for the therapy and prognosis of posttraumatic detachments is discussed.