Tears of the peripheral retina; pathogenesis, incidence and classification in autopsy eyes.

A pathogenic analysis of full-thickness tears of the peripheral retina and their incidence in autopsy eyes is presented. Tears were classified according to their location (ora or postora, quadrant and zone), type of traction (zonuloretinal or vitreoretinal), morphological features (flap or operculum), presence or absence of posterior vitreous detachment, and their association with other ocular lesions. Tears were present in 2% of eyes. They were postoral in 92%, uniformly distributed in the quadrants, in the equatorial zone in 95%, related to vitreoretinal traction in 94%, of the flap type in 64%, accompanied by posterior vitreous detachment in 79% and were significantly more prevalent in eyes with lattice degeneration (17%). A simple classification of postoral tears is recommended which incorporates these pathogenic principles and includes three types according to their topographical relationship to the vitreous base: intrabasal--caused by avulsion of zonular traction tufts; juxtabasal--related to traction of the posteriorly detached vitreous on irregularities in posterior border of vitreous base; extrabasal--resulting from avulsion of cystic retinal tufts.