Ocular higher-order aberrations and contrast sensitivity after conventional laser in situ keratomileusis.

PURPOSE: To investigate prospectively the relation between induced changes in higher-order aberrations of the eye and changes in contrast sensitivity by conventional laser in situ keratomileusis (LASIK) for myopia. METHODS: In 200 eyes of 110 consecutive patients (mean age, 32.7 +/- 8.4 years) undergoing LASIK, ocular aberrations and contrast sensitivity function were determined before and 1 month after surgery. The amount of myopic correction was 5.2 +/- 2.8 D (range, 1.0-13.0). Ocular higher-order aberrations were measured for a 4-mm pupil using the Hartmann-Shack wavefront analyzer (KR-9000PW; Topcon, Tokyo, Japan). The root mean square (RMS) of the third- and fourth-order Zernike coefficients was used to represent coma- and spherical-like aberrations, respectively. Total higher-order aberrations were calculated as the RMS of the third- and fourth-order coefficients. Contrast sensitivity and low-contrast visual acuity were measured. From the contrast sensitivity data, the area under the log contrast sensitivity function (AULCSF) was calculated. RESULTS: LASIK significantly improved logMAR best corrected visual acuity (Wilcoxon signed-rank test, P <0.001), but significantly reduced AULCSF (P <0.001) and low-contrast visual acuity (P=0.007). Total higher-order (P <0.001), coma-like (P <0.001), and spherical-like (P <0.001) aberrations were significantly increased after LASIK. The greater the amount of achieved myopia correction was, the more the changes in contrast sensitivity function and ocular higher-order aberrations were. The induced changes in AULCSF by LASIK showed significant correlations with changes in total higher-order (Pearson r=-0.221, P=0.003), coma-like (r=-0.205, P=0.006), and spherical-like (r=-0.171, P=0.022) aberrations. The changes in logMAR low-contrast visual acuity by surgery significantly correlated with changes in total higher-order (r=0.222, P=0.003), coma-like (r=0.201, P=0.007), and spherical-like (r=0.207, P=0.005) aberrations. CONCLUSIONS: Conventional LASIK significantly increases ocular higher-order aberrations, which compromise the postoperative contrast sensitivity function.

Visualizing the vitreous body in the anterior chamber using 11-deoxycortisol after posterior capsule rupture in an animal model.

OBJECTIVE: To develop a new technique to visualize vitreous body prolapsed in the anterior chamber using 11-deoxycortisol. STUDY DESIGN: Experimental study. METHODS: An animal model of posterior capsule rupture was developed to investigate the usefulness of 11-deoxycortisol, a precursor of cortisol without steroid activity. After the intentional creation of posterior capsule rupture, the suspension of 11-deoxycortisol was injected into the anterior chamber of rabbit eyes. After gentle irrigation and aspiration, the vitreous body that had prolapsed into the anterior chamber was removed using an anterior vitrectomy cutter. To investigate the safety of 11-deoxycortisol, the biomicroscopic appearance, intraocular pressure (IOP), corneal endothelial count, and microstructure of the corneal endothelium were examined in the rabbits that received injections of 11-deoxycortisol in the anterior chamber. RESULTS: In our posterior capsule rupture model, the vitreous in the anterior chamber became clearly visible, with 11-deoxycortisol showing white particles entrapped on its surface. The injection of 11-deoxycortisol facilitated the complete removal of the vitreous body from the anterior chamber. In intact rabbit eyes, most of the injected 11-deoxycortisol had disappeared from the anterior chamber by 12 hours after injection. The injection of 11-deoxycortisol had no effect on IOP, corneal endothelial density, or the microstructure of the corneal endothelium. CONCLUSIONS: The injection of 11-deoxycortisol in the anterior chamber is useful in visualizing the vitreous body and has no significant side effects. This technique might reduce the intraoperative and postoperative complications of anterior vitrectomy after posterior capsule rupture.