Placoid pigment epitheliopathy and Harada's disease.

Twenty-six patients are described who suffered from acute bilateral multifocal pigment epithelial disease. In 7 the pattern of disease was indistinguishable from acute posterior multifocal placoid pigment epitheliopathy, while in 8 it was indistinguishable from Harada's disease. In a further 9 cases the pigment epithelial disease was associated with serious detachment of the retina simulating Harada's disease but without systemic symptoms; spontaneous resolution occurred within a few days, and there was no recurrence. One additional case had short-lived disease with detachment initially, but this was followed by severe recurrence, and the last patient had serious detachment in 1 eye but not the other. When seen as a whole these patients appeared to represent a continuous spectrum of disease making it difficult to define boundaries between one condition and another. The difficulties in distinguishing diseases according to morphology alone are emphasised.