Visual functions affecting stereopsis in patients with branch retinal vein occlusion.

PURPOSE To quantify stereopsis and other visual functions in patients with unilateral branch retinal vein occlusion (BRVO) and to investigate vision-related parameters that affect stereopsis. DESIGN Prospective observational study. SUBJECTS Forty-five patients undergoing intravitreal ranibizumab (IVR) treatment for unilateral BRVO. METHODS We examined stereopsis using the Titmus stereo test (TST) and TNO stereotest (TNO), best corrected visual acuity (BCVA), letter contrast sensitivity, severity of metamorphopsia and degree of aniseikonia before and 6 months after IVR. MAIN OUTCOME MEASURES Visual functions that affect stereopsis. RESULTS Baseline stereopsis in patients with BRVO was 2.7 ± 0.6 (range, 1.6-3.5) in the TST and 2.8 ± 0.5 (range, 1.8-3.3) in TNO. TST and TNO scores were significantly correlated with BCVA and letter contrast sensitivity at baseline (P < 0.001) but not with other visual functions. IVR treatment significantly improved stereopsis, BCVA, and letter contrast sensitivity. After treatment, TST scores were significantly correlated with BCVA (P < 0.001), letter contrast sensitivity (P < 0.001), and aniseikonia (P < 0.01). TNO scores were significantly correlated with BCVA (P < 0.01) and letter contrast sensitivity (P < 0.01). TST and TNO scores after treatment were significantly correlated with BCVA at baseline (P < 0.01 for both). CONCLUSIONS Deterioration of stereopsis in patients with BRVO was associated with changes in visual acuity and contrast sensitivity after treatment. Initial visual acuity is a prognostic factor for posttreatment stereopsis.