Abstract
Abstract: :
Purpose : To describe findings observed by optical coherence tomography (OCT) in patients with toxoplasmic retinochoroiditis. We also compared OCT and Fundus Fluorescein Angiography (FFA) in active ocular toxoplasmosis. Methods : Prospective observational series. Patients were seen in a single referral center. The diagnosis of ocular toxoplasmosis was based on characteristic fundus lesions and positive Toxoplasma serology. Patients with active retinochoroiditis (group A) or inactive scars (group S) were included between November 2001 and August 2002 and were assessed by OCT. Presumed active lesions were analyzed by FFA, and retinal photography were performed in inactive cases. The Zeiss OCT2 imager (100 scans per section) was used in 21 eyes, and then the Zeiss OCT3 imager (500 scans per section) in 4 eyes. OCT analysis included an evaluation of macular thickness with 6 radial lines and additional radial lines centered on the area of retinochoroiditis. Results : There were 14 men and 11 women and the mean age of patients was 25.5 ± 9.9 years. A previous episode of active ocular toxoplasmosis was known in 15 patients (mean number of previous attacks in these patients : 1.2 ± 1.5). In 10 patients, no previous active retinochoroiditis was reported. Sixteen patients had active lesions (group A) and 9 patients presented with inactive scars (groups S). Cells in the anterior chamber and vitritis were noted respectively in 13 and 10 cases of group A and were absent in all cases of group S. In group A, vasculitis and papillitis were seen on FFA in 3 cases. Serous retinal detachment were detected both by FFA and by OCT in 2 cases, but only by OCT in 1 case. In group A, OCT images of lesions were seen as highly reflective areas in the superficial layers of the retina in 12/16 cases. Partial posterior vitreous detachment or vitreous condensations adjacent to active lesions were observed in 13/16 cases. In group S, no retinal edema or detachment of the sensory retina were seen by OCT. The retina was atrophic at the site of toxoplasmic scars. OCT showed highly reflective images in the underlying or adjacent pigment epithelium and choroid. The mean retinal thickness at the center of lesion was 353.1 ± 97.7 µm [range 184-615µm] in group A and 135.1± 95.3 µm [range 0-338µm] in group S (p<0.001). Conclusions : OCT is non invasive and usefully complements fluorescein angiography to analyze toxoplasmic retinochoroiditis.
Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, S • toxoplasmosis • chorioretinitis