Purpose: To evaluate the longitudinal anatomical response of retinal-choroidal anastomosis (RCA) to intravitreal ranibizumab injection using spectral-domain optical coherence tomography (SD-OCT).
Methods: We reviewed the medical records of 21 consecutive patients with RCA who underwent intravitreal ranibizumab injections at the University Eye Clinic of Creteil between January 2009 and June 2010. The SD-OCT features at baseline, at 3 months, and at 12 months were retrospectively analyzed. Based on SD-OCT, RCAs were classified as showing a focal retinal pigment epithelium (RPE) erosion ("erosion sign") over a small, localized RPE elevation; a focal RPE break leaving two free RPE flaps ("flap sign") at the level of a small, localized RPE elevation; or a large convex RPE prominence and a focal funnel-shaped RPE kissing an inverted focal funnel-shaped inner neuroepithelium ("kissing sign").
Results: Twenty-one eyes of 21 patients (3 men and 18 women, aged 81.6 ± 6.8 years) diagnosed with RCA naive to any treatment were included for analysis. Spearman ρ correlation between best-corrected visual acuity and lesion classification was 0.54 (P = 0.01) at Month 3 and 0.85 (P < 0.001) at Month 12. Eyes showing the flap sign at baseline underwent significantly less ranibizumab injections after the loading phase (2.14 ± 0.89 vs. 3.40 ± 0.96, P = 0.007) and showed a greater improvement in best-corrected visual acuity at Month 12 (from 0.52 ± 0.14 to 0.38 ± 0.15, P = 0.03) compared with eyes showing the kissing sign. At 12 months, 3 of 10 eyes with flap sign at baseline showed RCA activity, whereas 7 of 10 regressed to erosion sign phase. Of the 10 eyes with kissing sign at baseline, 6 progressed to a fibroglial scar.
Conclusion: A flap sign of RCA at baseline seems a favorable prognostic factor as concerns best-corrected visual acuity improvement and the need for retreatment.