OCT Patterns of Macular Edema in Intermediate Uveitis

Objective . To evaluate characteristic OCT morphological characteristic of initial presentation and chronic recurrent macular edema (ME) in patients with intermediate uveitis. Materials and methods . The study included 35 patients (46 eyes) with uveitic macular edema in intermediate uveitis. The first episode of macular edema was diagnosed in 20 patients (26 eyes), 15 patients (20 eyes) present with chronic recurrent macular edema. OCT was performed on the Optovue RTVue XR Avanti. The following OCT morphological characteristic were evaluated: integrity of IS/OS line, the presence of hyperreflective foci, inner nuclear layer cysts, Henle fibers layer cysts, small single cysts, diffuse retinal thickening without cystic changes, the presence of subretinal detachment. Results . Four OCT morphological variants of uveitic macular edema were identified: diffuse macular edema, small single cysts, cysts in Henle fibers layer and the inner nuclear layer with and without subretinal detachment. In the group with diffuse macular edema, the median duration of macular edema was 3 months, macular edema with Henle fibers cysts, inner nuclear layer cysts with subretinal detachment presented after 5 months (median), small single cysts and cystic changes in the layer of Henle fibers and the inner nuclear layer were detected at later times (12 and 36 months, respectively). A strong negative correlation was found between best-corrected visual acuity and central retinal thickness in chronic recurrent uveitic macular edema (correlation coefficient — 0.7, p = 0.0001), while a moderate negative correlation was established in macular edema at initial presentation (correlation coefficient — 0.55, p = 0.0031). Integrity of IS/OS line was observed significantly more often (p = 0.002) in chronic recurrent macular edema (10 (83.3%)) than at initial presentation (2 (16.6%)). In the presence of IS/OS disruption, best-corrected visual acuity was significantly lower (p = 0.016). Conclusion . Identified four OCT morphological variants of uveitic macular edema were characterized by different periods of its duration, which may reflect different stages of macular edema evolution. Chronic recurrent macular edema and ME at initial presentation in uveitis are distinguished by different OCT predictors, which should be taken into account in assessing the effectiveness of treatment and prognosis of visual acuity.