Purpose
To evaluate changes of the length of photoreceptor of inner (IS) and outer segment (OS) and a correlation between the changes and visual acuity after surgery for rhegmatogenous retinal detachment (RRD).
Methods
Patients who had undergone successful RRD repair with vitrectomy or scleral buckling and could be observed the IS /OS line at the central fovea in the spectral-domain optical coherence tomographic (OCT) images were retrospectively studied. Twenty-eight eyes of 28 patients were evaluated, and the eyes were classified preoperatively into those with macula-on RRD (n = 15, age 48.0 ± 16.9 years) and those with macula-off RRD (n = 13, age 54.8 ± 15.0 years). The central foveal thickness (CFT), the outer nuclear layer (ONL) thickness, and the length of IS and OS on the OCT images, and visual acuity were measured at 2 weeks, 1, 3, 6, and 12 months after surgery, respectively. We compared the length and the visual acuity.
Results
In the macula-off RRD group, the mean CFT and ONL thickness were 212 ± 51µm and 127 ± 54 µm, respectively, at 2 weeks after surgery and did not change with time significantly. However, the mean IS length was 25 ± 5 µm at 2 weeks after surgery and increased to 34 ± 3 µm at 12 months after surgery, and after postoperative 3 months elongated significantly compared to that at 2 weeks after surgery (p<0.001, ANOVA). Also, the mean OS length was 17 ± 10 µm 2 weeks after surgery and increased to 39 ± 9 µm at 12 months after surgery, and after postoperative 1 month elongated significantly compared to that at 2 weeks after surgery (p<0.01, ANOVA). In the macula-on RRD group, the mean CFT, ONL thickness, IS and OS length were 238 ± 15 µm, 126 ± 14 µm, 34 ± 3 µm and 44 ± 4 µm at 2 weeks after surgery and did not change with time. There was a significant difference in the OS length between the macular-off group and the macular-on group (p=0.042, t-test) at 12 months after surgery. The mean postoperative IS and OS length were significant correlated with the visual acuity in the macular-off group (r=-0.41, p<0.001; r=-0.63, p<0.001, Pearson).
Conclusions
The length of IS and OS was elongated with time significantly and was correlated with the visual acuity significantly in the macular-off RRD group. It was indicated that the restoration of IS and OS was correlated with the improvement of visual acuity after surgery for macular-off RRD.