Abstract
PURPOSE: To investigate axial length (AxL) variability and intraocular lens (IOL) power stability in macular edema (ME) patients undergoing intravitreal anti-VEGF therapy using Lenstar biometry. METHODS: In this preliminary observational study, 32 patients (64 eyes) with unilateral macular edema (ME) due to diabetic retinopathy or retinal vein occlusion were evaluated. AxL and IOL power were measured pre- and post-treatment using LenStar OLCR biometry. Three measurement strategies were employed: automated (AxLα), manually adjusted (AxLβ), and CRT-corrected (AxLγ). Four experienced ophthalmologists manually repositioned A-scan markers. Fellow eyes were assessed longitudinally. Statistical analyses included paired t-tests, intraclass correlation coefficients, and correlation tests. RESULTS: The mean patient age was 61.38 ± 9.44 years. Anti-VEGF treatment significantly reduced mean CRT from 444.47 ± 121.16 μm to 374.50 ± 98.90 μm (p < 0.001). The mean preoperative and postoperative AxL were 23.11 ± 0.72 mm and 23.10 ± 0.72 mm, respectively (p = 0.091), showing no significant change. However, in cases with CRT > 300 μm, AxL reduction was statistically significant (p = 0.044), though IOL power calculations remained stable (p = 0.401). Interobserver agreement was high for AxL and IOL power measurements, with intraclass correlation coefficients of 0.854 preoperatively and 0.989 postoperatively. Manual adjustments resulted in significant AxL differences between pre- and post-treatment periods (p < 0.001), while automated Lenstar measurements remained consistent. Fellow eyes IOL and AxL remained identical in both preoperative and postoperative sessions (p = 0.323 for IOL and p = 0.287 for AxL). CONCLUSION: This preliminary observational study suggests that AxL and IOL power measurements remain stable following anti-VEGF therapy in most ME cases. Small but consistent AxL changes in eyes with high CRT may indicate a structural threshold for biometric variability. OLCR-based biometry remains reliable in real-world practice.