Analysis of changes in individual retinal layer thickness after cataract surgery using spectral‐domain optical coherence tomography

Abstract

PurposeTo evaluate whether there were significant changes in macular thickness and each retinal layer thickness after cataract surgery using spectral‐domain optical coherence tomography (OCT)MethodsFrom February to August 2015, a prospective study of 24 eyes of 14 patients, who underwent cataract surgery was conducted. The thickness of each retinal layer was measured with OCT before and one month after surgery. The changes in OCT signal strength and retinal thickness before and after surgery were compared, and the layers more affected were confirmed. Also, correlation analysis was performed to determine the relationship between changes in signal strength, severity of cataract, and changes in refractive index and retinal thickness.ResultsThe mean macular thickness was significantly increased from 263.33 μm to 269.75 μm (p = 0.019). When examining the changes in each retinal layer thickness, there was a significant increase in the thickness of the inner plexiform layer (p = 0.034), outer nuclear layer (p = 0.015) and retinal pigment epithelium (RPE) (p = 0.012). The signal strength of OCT was significantly increased from 28.79 dB to 31.67 dB (p = 0.005), which was significantly correlated with postoperative macular thickness changes (p = 0.046). However, the severity of cataract (p = 0.219) or the change of refractive index (p = 0.098) was not significantly correlated with macular thickness changes.ConclusionsAfter cataract surgery, both improvement of signal strength and structural changes of the retina may increase macular thickness. In particular, the thickness of the inner plexiform layer, outer nuclear layer, and retinal pigment epithelial layer increased. Therefore, the thickness of ganglion cell‐inner plexiform layer after cataract surgery may increase, so it should be carefully considered in the assessment of glaucoma progression.