Tomographic Structural Changes of the Inner Retina after Internal Limiting Membrane Peeling for Idiopathic Epiretinal Membrane.

PURPOSE: To investigate the tomographic structural changes in the retinal layers after internal limiting membrane (ILM) peeling for idiopathic epiretinal membrane (ERM). METHODS: Sixty-nine eyes treated with vitrectomy and ILM peeling for idiopathic ERM were analyzed. Parafoveal retinal thickness was measured at baseline and 6 months after surgery. RESULTS: Total retinal thickness decreased significantly in the nasal and temporal subfields after surgery (p < 0.001), whereas the inner nuclear layer and outer nuclear layer showed nasal thickening (all, p < 0.001). The postoperative temporal/nasal subfield thickness ratio of each layer was significantly lower than that of fellow eyes. Eyes with larger ILM peeling showed a significantly lower temporal/nasal subfield thickness ratio (p = 0.033) than those with smaller sizes. CONCLUSIONS: The retinal thickness of each layer showed anatomical changes from ILM peeling and ERM removal. Nasal parafoveal thickening and temporal thinning occurred in the inner retinal architecture, which might be affected by ILM peeling size.

HIGHER-ORDER ABERRATIONS IN EYES WITH SILICONE OIL TAMPONADE.

PURPOSE: To investigate the changes in higher-order aberrations (HOAs) after silicone oil removal and to evaluate their associations with visual acuity. METHODS: Fifty-nine eyes of 58 patients who underwent SO removal were included. Total, corneal, and internal optic HOAs, and best-corrected visual acuity were measured before and 1 month after SO removal, and changes were compared between phakic and pseudophakic eyes. RESULTS: Total ocular and internal optic HOAs decreased significantly after SO removal both in pseudophakic (n = 40, all P < 0.001) and phakic eyes (n = 19, P = 0.017, P = 0.004). Preoperative HOAs (P < 0.001) and changes in HOAs (P = 0.006) were greater in pseudophakic eyes than in phakic eyes. Best-corrected visual acuity was significantly improved after SO removal, from 20/105 to 20/78 (P < 0.001) in pseudophakic eyes, whereas there was no difference in phakic eyes (P = 0.714). Preoperative HOAs and the reduction in HOAs after SO removal were greater in best-corrected visual acuity-improved eyes than best-corrected visual acuity-unchanged eyes (P < 0.001). CONCLUSION: Silicone oil tamponade induced an increase in HOAs, and these increases were greater in pseudophakic eyes than in phakic eyes. Silicone oil may cause additional visual impairments because of HOAs, beyond those caused by retinal diseases, particularly in pseudophakic eyes.

Acousto-Optic-Based Wavelength-Comb-Swept Laser for Extended Displacement Measurements.

We demonstrate a novel wavelength-comb-swept laser based on two intra-cavity filters: an acousto-optic tunable filter (AOTF) and a Fabry-Pérot etalon filter. The AOTF is used for the tunable selection of the output wavelength with time and the etalon filter for the narrowing of the spectral linewidth to extend the coherence length. Compared to the conventional wavelength-swept laser, the acousto-optic-based wavelength-comb-swept laser (WCSL) can extend the measureable range of displacement measurements by decreasing the sensitivity roll-off of the point spread function. Because the AOTF contains no mechanical moving parts to select the output wavelength acousto-optically, the WCSL source has a high wavenumber (k) linearity of R² = 0.9999 to ensure equally spaced wavelength combs in the wavenumber domain.