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Background: To report long‐term biometric and refractive outcomes in a group of Danish children after surgery for childhood cataract. Methods: Children between 7 and 18 years who had undergone uni‐ or bilateral cataract surgery at the Department of Ophthalmology, Rigshospitalet, Denmark, were examined in this cross‐sectional study. Swept source optical coherence tomography (OCT) based optical biometry (IOLmaster 700) and anterior tomography (Pentacam) was performed. Healthy fellow eyes from those with unilateral cataract were used as controls. Results: We included 56 children in the study with a median age at surgery of 43.8 months (1.6–137.6). The amount of higher order aberrations was significantly increased in operated eyes (median root mean square 0.461 μm [range 0.264–1.484]) compared with non‐operated eyes (median root mean square 0.337 μm [range 0.162–0.498], p < 0.001). Younger age at surgery was positively associated with more higher order aberrations at follow‐up (p < 0.001), but we found no significant associations between the amount of higher order aberrations and visual acuity or contrast vision. Longer axial length was associated to glaucoma while shorter axial length was associated to strabismus (p < 0.001). Conclusions: Eyes operated for childhood cataract have higher order aberrations compared with non‐operated eyes. Higher order aberrations are complex refractive errors that cannot be corrected by normal lenses and may contribute to poor visual outcomes for the children. We found an association between young age at surgery and higher order aberrations. [ABSTRACT FROM AUTHOR]

Background To evaluate the biometric factors associated with the accuracy of intraocular lens power predictions for cataract surgery in primary angle-closure (PAC) or primary angle-closure glaucoma (PACG) eyes. Design Cross-sectional study Participants This study included 103 PAC or PACG patients who had undergone cataract surgery. Methods All participants underwent anterior-segment optical coherence tomography preoperatively. Two novel biometric factors - the relative lens vault (the ratio of lens vault to anterior vault) and the anterior vault (the sum of lens vault and anterior chamber depth) - were measured using customized software. The powers of the implanted intraocular lens and the actual postoperative refractive errors were compared. The mean refractive error and the median absolute error were calculated and compared using repeated measures ANOVA and Wilcoxon matched-pairs signed-rank test. The biometric factors associated with the postoperative refractive error were investigated by multivariate regression analysis. Main Outcome Measures Preoperative anterior-segment biometric factors, difference between predicted and actual postoperative refraction. Results The Haigis, Hoffer Q and SRK/T formulas all showed a slight tendency toward resultant hyperopia, respectively ( P < 0.001, P = 0.05, P = 0.003). The Hoffer Q formula had the least prediction error ( P < 0.001). In the multivariate regression analysis, the relative lens vault was the only independent factor predicting postoperative refractive error ( β = 0.392, P = 0.011). Conclusion Intraocular lens power predictions for cataract surgery in PAC or PACG patients can be inaccurate. Such results might be associated with anterior-segment biometric factors. Preoperative relative lens vault appears to be a significant factor predicting refractive outcome after cataract surgery in patients with PAC or PACG. [ABSTRACT FROM AUTHOR]

Background To compare anterior segment biometric parameters between Caucasians and Chinese before and after laser peripheral iridotomy. Design Prospective clinical cohort study. Participants Caucasian and Chinese primary angle-closure suspects. Methods Anterior segment optical coherence tomography images captured before and after laser peripheral iridotomy were analysed to measure anterior segment biometric parameters. Paired Student's t-tests were used for within-ethnic group comparisons. Univariate and linear mixed-effect regression models were used for between-ethnic group comparisons. Main Outcome Measures Angle opening distance, angle recess area, iris thickness, iris curvature, anterior chamber area, anterior chamber volume and anterior chamber width. Results Caucasians had significantly greater preoperative angle recess area, anterior chamber width, and iris curvature and lower preoperative iris thickness compared to Chinese ( P < 0.05). Significant postoperative increases in angle opening distance, angle recess area, anterior chamber area, anterior chamber volume, and anterior chamber width along with significant postoperative decrease in iris curvature were observed within both ethnic groups ( P < 0.05). However, the amount of laser peripheral iridotomy-induced changes in angle opening distance, angle recess area, anterior chamber area, anterior chamber volume, anterior chamber width, and iris curvature did not differ between the two ethnic groups ( P < 0.05). Conclusion Both Caucasian and Chinese demonstrated opening of anterior chamber angle width, expansion of anterior chamber dimensions, and flattening of iris convexity after laser peripheral iridotomy. Although certain aspects of anterior segment anatomy differed between Caucasians and Chinese preoperatively, they did not translate into significant ethnic differences in the amount of laser peripheral iridotomy-induced changes in the anterior segment biometric parameters. [ABSTRACT FROM AUTHOR]

A bstract Background: To compare the anterior segment biometric parameters amongst adult American Caucasians, American Chinese and mainland Chinese, in order to determine parameters that may contribute to increased risk for angle closure in Chinese. Design: Cross-sectional clinic-based study Participants: Four gender- and age-matched cohorts included Caucasians, American Chinese, Southern and Northern mainland Chinese. Methods: Anterior segment optical coherence tomography was utilized to image the anterior chamber. Customized software was used to calculate the anterior segment parameters. Main Outcome Measures: Anterior chamber depth, anterior chamber width, lens vault and corneal arc depth. Results: Data from 121, 124, 121 and 120 subjects were available for American Caucasian, American Chinese, and Southern and Northern Mainland Chinese subjects, respectively. Caucasians had significantly greater anterior chamber depth, anterior chamber width and corneal arc depth than all Chinese groups even after adjustment for refractive status and axial length. In multiple regression analysis, predictors of greater lens vault were female gender, older age and more hyperopic/less myopic status for both racial groups. It was found only in Chinese that female and older subjects tended to have smaller anterior chamber depth, anterior chamber width and corneal arc depth. Conclusion: The shallower anterior chamber in Chinese than Caucasians is likely attributable to the shorter corneal arc depth in the former group. Moreover, the smaller anterior chamber width contributes to more crowded anterior chambers in Chinese than in Caucasians. The more anteriorly located lens under a less vaulted cornea in Chinese females compared with Chinese males may account for the higher risk of angle closure in this subpopulation. [ABSTRACT FROM AUTHOR]