Holmberghodges4648

To determine and compare the origin of the external surface reflections produced by commonly used intraocular lenses (IOLs).

The specular reflection taking place at the anterior surface of eight types of IOLs (IOL power = 22.00 diopters [D]) with different refractive indices (RIs), optical design, and ultraviolet and blue light-filtering function were measured. The experimental set-up included a laser beam light source (3.5 mW, 532 nm) and a saline-filled model eye containing the IOL to be examined. External surface reflections were measured using a power meter, and the IOL surface reflectance (%) was compared among the eight IOLs investigated.

External reflections from the anterior surface of the studied implants increased as the RI of the IOL material increased. The IOL models composed of high RI material (RI = 1.56 ± 0.02) were found to have a more than threefold higher external surface reflections compared to those with low RI (RI = 1.45 ± 0.02). Ultraviolet or blue light-filtering functions showed no significant correlation with the external reflectance.

IOLs with a high RI are associated with external surface reflections that are more than threefold higher than those with lower RI. The "cat's eye" phenomenon seen in pseudophakic eyes by an outside observer strongly depends on the RI, but is independent of the filter incorporated in the IOL.

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IOLs with a high RI are associated with external surface reflections that are more than threefold higher than those with lower RI. The "cat's eye" phenomenon seen in pseudophakic eyes by an outside observer strongly depends on the RI, but is independent of the filter incorporated in the IOL. [J Refract Surg. 2021;37(6)398-402.].

To evaluate an automated method for detecting the cone shape characteristics and to assess the cornea specialists' subjective variability of these measures using different maps.

Topographic images of the anterior and posterior surface of each eye were presented to 12 clinicians in two different types of map tangential curvature and relative elevation to the best-fit sphere. They were asked to mark the cone center and its boundaries in the two maps without knowing that they belonged to the same patient. The results between the maps were compared to assess the subjective variability dependent on the map type and the automated method was compared against both estimations to assess its accuracy.

Considering the results of anterior and posterior surfaces, there was low agreement between the cone center estimations using different types of maps for 10 of the 12 cases (

< .05), whereas the comparison between the automated method and the two map estimations did not show differences in 11 of the 12 cases (

> .05). There was high variability, up to 55%, among clinicians' estimations of the cone area. The results of the automated method were within the range of the expert's estimations.

An objective, mathematically derived method of determining morphological dimensions of the cone was consistent with clinicians' evaluations. Although there was high variability among the experts' subjective estimates, which were highly influenced by the type of map, the objective method provided a reliable evaluation of the keratoconus shape independent of maps or color scale.

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An objective, mathematically derived method of determining morphological dimensions of the cone was consistent with clinicians' evaluations. Although there was high variability among the experts' subjective estimates, which were highly influenced by the type of map, the objective method provided a reliable evaluation of the keratoconus shape independent of maps or color scale. [J Refract Surg. 2021;37(6)414-421.].

To assess epithelial corneal remodeling by anterior segment optical coherence tomography (AS-OCT) after intracorneal ring segments (ICRS) implantation in keratoconic eyes.

This prospective observational study included patients with keratoconus receiving ICRS of different arc lengths according to their tomographic pattern. AS-OCT and corneal topography (Scheimpflug camera) were performed before and 1, 3, and 6 months after surgery. Corneal pachymetry mapping was performed and total corneal and epithelial thicknesses (3-mm central and 16 points on 6-mm zone) were measured over the pupil center using AS-OCT. Topographic parameters were also assessed.

A total of 68 keratoconic eyes were analyzed (Amsler-Krumeich stages 1 to 4) in four groups of 17 eyes 210° ICRS, 320° ICRS, double 160° ICRS, and single 160° ICRS. Corneal pachymetry mapping revealed that epithelial thickness increased significantly in the internal zones juxtaposed to the ICRS without smoothing during the postoperative period (

< .05). Mean maximum epithelial thickness increased from 67 ± 6 to 79 ± 7 µm for 210° ICRS, 66 ± 9 to 82 ± 4 µm for 320° ICRS, 63 ± 6 to 78 ± 7 µm for double 160° ICRS, and 62 ± 5 to 77 ± 5 µm for single 160° ICRS (

< .0001). Significant epithelial thickening at the apex of the cone was observed in all groups (

< .05).

Significant epithelial thickening occurs after ICRS implantation adjacent to the ICRS to compensate for the ridge created with a thickening of epithelium over the cone due to regularization of the stromal surface.

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Significant epithelial thickening occurs after ICRS implantation adjacent to the ICRS to compensate for the ridge created with a thickening of epithelium over the cone due to regularization of the stromal surface. [J Refract Surg. Selleckchem FI-6934 2021;37(6)404-413.].

To evaluate the short-term outcomes of implantation of a full-diffractive multifocal intraocular lens (IOL) with optic capture for selected pediatric cataracts.

In this prospective study, patients with pediatric cataract aged 3 to 14 years were selected to receive multifocal IOL (Tecnis ZMB00; Abbott Medical Optics) posterior optic capture. Visual acuity, stereopsis, visual quality, and complications were assessed.

Forty-five patients (66 eyes) were recruited with a follow-up of 9.09 ± 5.93 months (range 6 to 24 months). The cataract was bilateral in 21 patients and unilateral in 24 patients. At the last follow-up visit, the mean distance-corrected distance, intermediate, and near visual acuity was 0.28 ± 0.25, 0.43 ± 0.24, and 0.39 ± 0.27 logMAR, respectively. Among the patients with bilateral cataract, postoperative corrected distance visual acuity (CDVA) was 20/40 or better in 79% (33 of 42) of the eyes and 20/20 in 26% (11 of 42) of the eyes. Of the patients with unilateral cataract, 54% (13 of 24) achieved a CDVA of 20/40 or better but none obtained a CDVA of 20/20.