Retinal vascular involvement in acute toxoplasmic retinochoroiditis.

The present study deals with the retinal vascular involvement in 64 patients with toxoplasmic retinochoroiditis during the acute phase of the disease and its evolution. Vascular involvement was noted in all 64 eyes during the acute phase of the disease. In 59 (92%) out of 64 cases the vascular involvement was located in the same retinal quadrant as the active toxoplasmic lesion. In the remaining 5 eyes (8%) the vascular participation was found in all four retinal quadrants. In 3 (5%) out of 64 cases, the vascular infiltration was extremely severe and resulted in retinal vascular obstruction. In all three cases the vessel traversed the active toxoplasmic lesion. In 35 (55%) out of 64 patients the initial vascular picture changed in the course of the acute phase of the disease. In these patients, the lesions had extended to the adjacent vessels or to other parts of the involved vessel. In the further course of the evolution of the active toxoplasmic lesion, the vascular involvement did not persist indiscriminately. It was noted that in 14 (22%) out of 64 cases the vascular lesions gradually regressed and eventually disappeared together with the active toxoplasmic lesion and the formation of the retinochoroidal scar. In the remaining 50 (78%) out of 64 cases the vascular involvement either disappeared after the establishment of the retinochoroidal scar in 3-12 months (29 cases) or remained permanently (21 cases).