To evaluate the extent of the visual impairment caused by uveitis-associated cystoid macular edema (CME) and compare the results with lesion size.

Observational case series.

setting: Uveitis outpatient clinic of the Department of Ophthalmology and Optometry, Medical University of Vienna. patient population: CME was verified in 30 eyes of 30 consecutive uveitis patients with optical coherence tomography and lesion size was assessed with retinal thickness analyzer. main outcome measures: Distance visual acuity (VA) (measured with Early Treatment Diabetic Retinopathy Study charts), reading acuity, and reading speed (tested with Radner Reading Charts). Results were compared with nonaffected partner eyes.

Distance VA was logMAR 0.22 ± 0.15 in CME eyes vs −0.02 ± 0.17 in healthy controls. Reading acuity was 75% of logMAR in CME eyes vs 92% of logMAR in control eyes (P = .01). The mean reading speed was 148.4 ± 36.6 words per minute in patients with CME vs 168.9 ± 36.3 in patients without CME (P = .04). Reading acuity correlated with both lesion size and distance VA (r = 0.61; P = .01 and r = 0.53; P = .028, respectively). Neither anatomical classification of uveitis nor gender or age had a significant influence on the evaluated parameters.

Reading acuity and reading speed were considerably more impaired than distance visual acuity. The assessed parameters showed a better correlation to lesion size and seem to be a better reflection of macular dysfunction. Analyzing reading function is an important factor when following patients with CME and evaluating success of treatment modalities.