Contrast-to-noise ratio is a useful predictor of early displacement of large submacular hemorrhage by intravitreal sf6 gas injection.

PURPOSE:To investigate predictors of early displacement of submacular hemorrhage (SMH) by simple intravitreal SF6 gas injection. METHODS:This retrospective study included 16 eyes of 16 consecutive patients (age: 74.5 ± 7.7 years; 15 men) with large SMH treated with simple intravitreal SF6 gas before inception of subretinal tissue plasminogen activator injection at our institution. The SMH displacement was graded at 1-week posttreatment as 0, 1, or 2. Central retinal thickness, central choroidal thickness, SMH height, SMH area, disease duration, use of anticoagulant or antiplatelet drugs, and contrast-to-noise ratio (CNR) of SMH on optical coherence tomography images were recorded. Correlations between displacement grading and baseline parameter were analyzed. RESULTS:Univariable correlation analysis revealed association of the 1-week displacement grading with the CNR (P = 0.004; r = -0.68) and SMH height (P = 0.03; r = -0.55). The CNR was most strongly associated with 1-week displacement on multivariable correlation analysis (P = 0.01; β = -0.60). CONCLUSION:Findings of the present study showed that the CNR of SMH was a useful predictor of early displacement of large SMH after simple intravitreal SF6 gas injection. When vitrectomy with subretinal injection of tissue plasminogen activator is difficult in patients with large SMH, with low CNR on optical coherence tomography, simple intravitreal SF6 gas injection may be a treatment option.