[The ocular fundus findings in dengue fever]

From September to December of 1988, 24 cases of clinical diagnosed dengue fever accompanied by visual disturbances were studied. A detailed history and a detailed ocular examination including visual acuity, slit lamp examination, fundus examination through dilated pupil and fluorescein angiography were conducted. In some cases, Amsler grid, visual field, visual evoked potential and color vision test were also evaluated. The chief complaints of these 24 patients were blurred vision, central scotoma, floaters, photophobia and halo vision. The intervals between onset of fever and awareness of blurred vision were 2 to 15 days with an average of 7.26 days. The ocular fundus changes included macular hemorrhage, retinal hemorrhage, maculopathy, Roth's spot, diffuse retinal edema, peripapillary hemorrhage vitreous cells and blurring optic disc. The fluorescein angiographic findings included poor choroidal flushing, delayed disc filling, disc extravasation, block fluorescence, capillary obliteration, non filling of macular network, capillary leakage and window defect. Seventeen cases (30 eyes) were followed-up for 2 weeks to 3 months. Visual recovery was good in most of the cases. However, 2 cases (4 eyes) showed poor visual outcome. In this series studied, the principle ocular fundus change caused by dengue fever was macular hemorrhage. This may be due to the capillary changes near the macular area. But in some of the cases, the direct viral invasion and/or indirect changes of the optic nerve, the retinal pigment epithelium or photoreceptors should be considered.