Organised macular plaques in exudative diabetic maculopathy.

Plaques of hard exudate measuring 0-5 to 10 disc diameters, which occurred in 5 eyes of 4 patients with diabetic maculopathy, showed complete organisation in 8 to 18 months with the formation of scars measuring 0-2 to 0 5 disc diameters. The visual acuity was related to the size and situation of the scar within the fovea, and, when the foveola was involved by plaque formation, visual reduction did not progress with subsequent formation of scar tissue. Fluorescein angiograms showed absence of ingrowing choroidal neovascularisation and a discrete residual hyperfluorescence beneath the resolving plaques and within the scar tissue, which resembled a serous detachment of pigment epithelium but may have resulted from a combination of pigment atrophy and leakage from retinal capillaries. This late clinical appearance may be the only ophthalmoscopic evidence that a severe exudative maculopathy has been primarily responsible for severe visual loss, and should be differentiated from cicatricial disciform lesions in older patients. The absence of ingrowing choroidal neovascularisation, subretinal haemorrhage, and pronounced serous retinal detachment substantiates our previous conclusions based on a morphological study from a limited number of sections that the origin of the fibrous replacement was not choroidal but was derived partly from the pigment epithelium and partly from the retinal vasculature. Juxtaposition of a deeply situated hard exudate plaque and the retinal pigment epithelium may initiate focal metaplasia and subsequent organisation with scar formation.