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Purpose: Evaluate the impact of high vs low intraoperative intraocular pressure (IOP) during phacoemulsification on anterior and posterior physiology., Setting: Private practice in Des Moines, Iowa., Design: Prospective, randomized, paired-eye clinical trial of patients anticipating bilateral cataract surgery., Methods: 27 participants randomized at the time of their first cataract surgery to either low IOP or high IOP group. The subsequent cataract surgery was performed under the alternate condition. During phacoemulsification and cortex removal, IOP was maintained either at low (≤28 mm Hg) or at high (≥55 to 60 mm Hg) levels. The primary outcome was fluid usage, with secondary outcomes of central corneal thickness, foveal avascular zone area, foveal and macular thickness, endothelial cell density (ECD), and postoperative inflammation., Results: Surgery with low IOP settings used less fluid (40.0 mL vs 55.6 mL, P < .0001). Corneal thickness changes were smaller in low IOP eyes at 1 day and 1 week (3.0% vs 8.1%, P = .01; 3.1% vs 4.4%, P = .01) but were similar by 1 and 3 months. ECD dropped less in low IOP eyes at 1 and 3 months (-1.7% vs -12.3%, P = .001, 2.1% vs -8.9%, P = .0003.) IOP remained a significant predictor of ECD change when relationship was controlled for fluid use and phacoemulsification energy. Retinal parameters did not vary among all eyes or when compared by IOP setting. Visual acuity was similar at all timepoints., Conclusions: Low IOP settings resulted in less inflammation and less corneal trauma, as evidenced by a smaller drop in ECD and less postoperative corneal edema, when compared with high IOP settings. Retinal parameters did not change significantly. The different outcomes did not result in a difference in visual acuity., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of ASCRS and ESCRS.)

Purpose: To evaluate the repeatability of a new swept source optical coherence tomography (SS-OCT)-based biometer to measure anterior segment parameters and to assess the agreement with 3 other imaging devices based on different measurement principles., Setting: Unit of Eye and Vision, Department of Clinical Neuroscience, Karolinska Institute, Stockholm, Sweden., Design: Prospective, comparative case series., Methods: 3 consecutive measurements were obtained in unoperated eyes with the Eyestar900 (SS-OCT), Lenstar 900, MS-39, and Sirius. The following anterior segment parameters were evaluated: central corneal thickness (CCT), corneal diameter (CD), aqueous depth (AQD), and corneal power metrics. The repeatability limit (Rlim), coefficient of variation (CoV), and a repeated measures Bland-Altman analysis were performed., Results: 74 eyes of 74 participants were measured. The Rlims for CCT, CD, and AQD were lower than 10 μm, 0.3 mm, and 0.10 mm for all devices, respectively. The corresponding CoVs for these parameters never exceeded 1.2%. The Rlim for the corneal power metrics never exceeded 0.60 diopter (D) for any of the instruments. Lenstar showed the best agreement with the MS-39 to measure CCT, CD, and AQD (limit of agreement interval, LoA: 15.54 μm, 0.55 mm, and 0.16 mm, respectively). The mean difference for keratometry parameters was lower than 0.3 D for all device comparisons, and the LoA interval ranged between 0.52 D and 1.21 D., Conclusions: The repeatability for measuring anterior segment parameters was good, and the agreement among all the instruments was good for CD and AQD measurements. However, for CCT and keratometer parameters, the instruments cannot be used interchangeably due to large LoA interval., (Copyright © 2023 The Author(s). Published by Wolters Kluwer Health, Inc. on behalf of ASCRS and ESCRS.)

Purpose: To systematically observe and analyze the signs of deficient posterior capsule in posterior polar cataracts., Design: Ambispective observational study., Participants: Cases with posterior polar cataracts., Methods: Eyes with diagnosed posterior polar cataracts were imaged on anterior segment optical coherence tomography (AS-OCT). A detailed assessment was performed to note the morphology of the posterior opacity, posterior capsule, and the common patterns to indicate their abnormality. In addition, generalized observation of the morphology was also performed about intraoperative surgical experiences., Results: A total of 101 eyes were included. Mean patient age was 52.85 ± 10.72 years. The posterior capsule integrity was identified as intact in 91 eyes and abnormal/deficient in 10 eyes (9 had intraoperative defective capsule). These deficient/abnormal morphologies were classified into 3 categories: conical (n = 2), moth-eaten (n = 5), and (3) ectatic (n = 3). Similarly, depending on the presence of hypoechoic spaces between the opacity and the capsule, remaining posterior polar cataracts were categorized into 2 generalized morphological types: without hypoechoic areas (n = 40) and with hypoechoic areas (n = 51). In the without hypoechoic areas group, 6 cases developed capsular rent; in the with hypoechoic areas group, 1 case developed capsular rent., Conclusions: In posterior polar cataracts, the deficient/abnormal capsular morphology could be specifically categorized into 3 categories, conical, moth-eaten, and ectatic types. In addition, to predict the ease of intraoperative separation between the opacity and the capsule, generalized categorization might help in better case management.

Purpose: To determine the efficacy of the femtosecond laser with integrated anterior segment optical coherence tomography (AS-OCT) for the detection of posterior capsular dehiscence in posterior polar cataracts (PPCs). To evaluate the safety of phacoemulsification in these eyes undergoing femtosecond laser-assisted cataract surgery (FLACS)., Setting: Centre For Sight Group of Eye Hospitals, a chain of tertiary eyecare hospitals in India., Design: Prospective interventional case series., Methods: The study included eyes with PPCs undergoing FLACS using the CATALYS femtosecond platform. Real-time OCT guidance was used to image the posterior capsule (PC), which was then classified as intact or dehiscent. The femtosecond laser was used for the creation of capsulotomy, nuclear fragmentation, and corneal incisions. In all eyes, the posterior offset (distance between the posterior extent of nucleotomy and the PC) was increased to enable a thick epinuclear cushion. Intraoperative status of the PC was noted, and the specificity and the sensitivity of AS-OCT to detect a preexisting posterior capsular defect was determined., Results: The cohort included 50 eyes (40 patients), in which a posterior capsular discontinuity on AS-OCT was observed in 7 eyes (14%). Five (10%) of these 7 eyes developed an intraoperative posterior capsular rent (PCR) A sensitivity and negative predictive value of 100% was noted. No case of nucleus drop was noted., Conclusions: Femtosecond laser with integrated AS-OCT is a relevant and helpful tool to detect and increase the safety in preexisting posterior capsular dehiscence, alerting the surgeon ahead of phacoemulsification.

Purpose: To determine whether vault measurements after placement of a hole implantable collamer lens (hole ICL) (KS-AquaPORT) can be predicted by angle-to-angle (ATA) and white-to-white (WTW) measurements obtained with anterior segment optical coherence tomography (AS-OCT)., Setting: Sanno Hospital, Tokyo, Japan., Design: Retrospective case series., Methods: Eyes were observed for 3 months after hole ICL implantation for myopia or myopic astigmatism. Central vault, ATA, and WTW measurements were obtained before and after surgery using the swept-source AS-OCT CASIA2 system., Results: The study included 44 eyes (23 patients). The mean patient age and preoperative spherical equivalent, ATA, and WTW values were 36.2 years ± 8.8 (SD), -6.23 ± 3.41 diopters (D), 12.03 ± 0.40 mm, and 11.72 ± 0.40 mm, respectively. The safety index and efficacy index 3 months postoperatively were 1.13 ± 0.21 and 0.91 ± 0.30, respectively. Regarding predictability, 93.2% of eyes were within ±0.50 D of the attempted correction and all eyes were within ±1.00 D. The reproducibility coefficients for the ATA distance and WTW distance were 0.998 and 0.960, respectively. The mean postoperative central vault was 491.6 ± 189.5 μm. There was a significant correlation between postoperative vault and the ICL size and ATA distance (Spearman rank correlation coefficient r = 0.59, P < .001) but not between the ICL size and WTW distance (r = 0.27, P = .08)., Conclusion: The ATA measurements had higher reproducibility than the WTW measurements on AS-OCT, making it is a more important predictor of postoperative vault., (Copyright © 2019 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Purpose: To investigate the safety and efficacy of the intraoperative use of a triphasic polymeric gel as corneal coating during cataract surgery and its effect on postoperative ocular comfort., Setting: Eye Clinic, University of Florence, Italy., Design: Longitudinal observational retrospective study., Methods: Data on patients who received an application of a polysaccharide blend of hydroxypropyl methylcellulose, xanthan gum, and carrageenan (EyeDRO) on the corneal surface and data on patients who received a balanced salt solution during phacoemulsification surgery were analyzed. The central corneal thickness (CCT) and epithelial thickness were examined using anterior segment optical coherence tomography, and the corneal basal epithelial cell (BEC) and Langerhans cell densities by in vivo confocal microscopy. The ocular surface disease index (OSDI) score, tear breakup time (TBUT), and Schirmer test I values were evaluated., Results: The study comprised data on 28 patients in the coating gel group and 26 patients in the balanced salt solution group. In the coating gel group, the CCT and epithelial thickness values returned to the baseline value within 5 and 15 postoperative days, respectively; the BEC and Langerhans cell densities returned to baseline levels within 15 and 30 postoperative days. In the balanced salt solution group, the mean BEC and Langerhans cell densities were significantly different from the preoperative values at all follow-up assessments. The TBUT returned to the preoperative level at day 5 in the coating gel group. The OSDI scores returned to the preoperative values after 15 days in the coating gel group and 30 days in the balanced salt solution group., Conclusions: The use of a tripolymeric gel as a corneal coating during cataract surgery played a protective role on the corneal surface and reduced postoperative discomfort symptoms., (Copyright © 2019. Published by Elsevier Inc.)

Purpose: Role of anterior segment optical coherence tomography (AS-OCT) for safer management of mature white cataracts., Setting: Patients with mature white cataracts attending the outpatient department of a tertiary eye care hospital, aspiring to have cataract surgery performed, were scheduled for elective phacoemulsification and intraocular lens implantation by two surgeons during the period of October 2017 to March 2018., Design: A prospective interventional study of 30 patients., Methods: All patients with mature cataracts and absence of any retinal pathology had AS-OCT to assess the presence or absence of intralenticular subcapsular fluid pockets. The patients with the presence of subcapsular fluid pockets (Group 1) underwent 30-gauge needle aspiration fluid aspiration followed by capsulorhexis and phacoemulsification and those without any fluid (Group 2) underwent Utrata forceps-assisted capsulorhexis., Results: The study comprised 30 eyes of 30 patients, of which 15 eyes (50%) had subcapsular fluid and 15 eyes (50%) had no fluid on AS-OCT. Of the 15 eyes in Group 1, 13 eyes (86.7%) underwent complete circular curvilinear capsulorhexis (P = .001), with a surgical success rate of 87%, whereas 2 eyes (13.3%) had capsular runaway complications. Of the 15 eyes with no subcapsular fluid, 13 eyes (86.7%) underwent complete circular curvilinear capsulorhexis (P = .001), whereas 2 eyes (13.3%) had posterior capsule rupture. Thus, 87% of the cases had uneventful capsular outcomes in each group., Conclusion: The detection of subcapsular fluid on AS-OCT allows better planning and management with 30-gauge assisted-needle drainage of fluid, thus decreasing the chances for capsular runaway complications with better surgical outcomes., (Copyright © 2018 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Purpose: To determine whether preoperative assessment of posterior capsule integrity using anterior segment optical coherence tomography (AS-OCT) can predict posterior capsule dehiscence in patients with posterior polar cataract having phacoemulsification., Setting: Aravind Eye Hospital and Postgraduate Institute of Ophthalmology, Pondicherry, India., Design: Prospective observational study., Methods: Patients with posterior polar cataract who had phacoemulsification between October 2012 and November 2013 were included in the study. Preoperative AS-OCT imaging was performed to assess the integrity of the posterior capsule. Anterior segment OCT images of the posterior capsule were graded as "intact" or "dehiscent." Phacoemulsification was performed by the same surgeon who was masked from the AS-OCT findings. The integrity of the posterior capsule was evaluated by the surgeon intraoperatively., Results: The study comprised 64 eyes of 62 patients. Preoperative AS-OCT showed 8 eyes (12.5%) to have probable posterior capsule dehiscence and 56 eyes (87.5%) to have intact posterior capsules. Intraoperatively, the surgeon noted posterior capsule dehiscence in 5 eyes (7.8%) and an intact posterior capsule in 59 eyes (92.2%). The sensitivity and specificity of AS-OCT for detecting posterior capsule dehiscence was 100% and 94.92%, respectively. The negative predictive value of AS-OCT was 100%., Conclusion: Anterior segment OCT with its high negative predictive value can be used successfully to predict the risk for posterior capsule rupture during phacoemulsification in eyes with posterior polar cataract., (Copyright © 2018 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Purpose: To evaluate the repeatability of automatic measurements by a new anterior segment optical coherence tomographer (AS-OCT) combined with Placido topography and their agreement with those provided by 2 rotating Scheimpflug cameras., Setting: G.B. Bietti Foundation IRCCS, Rome, Italy., Design: Evaluation of a diagnostic test instrument., Methods: Unoperated eyes and eyes with previous myopic excimer laser surgery were analyzed. Three consecutive scans were acquired with an AS-OCT device (MS-39) and 1 with 2 rotating Scheimpflug cameras (Pentacam HR and Sirius). The following parameters were evaluated: simulated keratometry, posterior and total corneal power, total corneal astigmatism, corneal asphericity, thinnest corneal thickness, central epithelial thickness, corneal diameter, and aqueous depth. Repeatability was assessed using test-retest variability, the coefficient of variation (CoV), and the intraclass correlation coefficient; agreement was assessed by the 95% limits of agreement., Results: The study comprised 96 unoperated eyes and 43 eyes with previous myopic excimer laser surgery. High repeatability was achieved in both groups, as shown by a CoV less than 1.0% for most parameters. The repeatability of epithelial thickness was slightly lower than that of the whole corneal thickness, although the CoV was still good (1.87% in unoperated eyes; 3.28% in post-refractive surgery eyes). Moderate repeatability was found for total corneal astigmatism measurements, with a CoV greater than 20.0%. Agreement with Scheimpflug cameras was high for aqueous depth and thinnest corneal thickness and moderate for most other parameters., Conclusion: The high repeatability of automatic measurements by the new AS-OCT device supports its use in clinical practice., (Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.)

Purpose: To determine whether relatively low-resolution ultrasound biomicroscopy (UBM) can be used to predict the accommodative optical response in prepresbyopic eyes as well as in a previous study of young phakic subjects, despite lower accommodative amplitudes., Setting: College of Optometry, University of Houston, Houston, USA., Design: Observational cross-sectional study., Methods: Static accommodative optical response was measured with infrared photorefraction and an autorefractor (WR-5100K) in subjects aged 36 to 46 years. A 35 MHz UBM device (Vumax, Sonomed Escalon) was used to image the left eye, while the right eye viewed accommodative stimuli. Custom-developed Matlab image-analysis software was used to perform automated analysis of UBM images to measure the ocular biometry parameters. The accommodative optical response was predicted from biometry parameters using linear regression, 95% confidence intervals (CIs), and 95% prediction intervals., Results: The study evaluated 25 subjects. Per-diopter (D) accommodative changes in anterior chamber depth (ACD), lens thickness, anterior and posterior lens radii of curvature, and anterior segment length were similar to previous values from young subjects. The standard deviations (SDs) of accommodative optical response predicted from linear regressions for UBM-measured biometry parameters were ACD, 0.15 D; lens thickness, 0.25 D; anterior lens radii of curvature, 0.09 D; posterior lens radii of curvature, 0.37 D; and anterior segment length, 0.42 D., Conclusions: Ultrasound biomicroscopy parameters can, on average, predict accommodative optical responses with SDs of less than 0.55 D using linear regressions and 95% CIs. Ultrasound biomicroscopy can be used to visualize and quantify accommodative biometric changes and predict accommodative optical response in prepresbyopic eyes., (Copyright © 2015 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

We describe a surgical technique of transscleral suture fixation for recurrent rotation of a double-loop hydrophilic acrylic toric intraocular lens (IOL) in the capsular bag. Two 9-0 polypropylene sutures are placed in the proximal and distal angulations of 1 of the IOL haptics through the capsular bag. The clockwise and counterclockwise traction provided by these sutures prevents rotation of the IOL in either direction. This technique can be used in cases of spontaneous postoperative IOL rotation to achieve stabilization. In the case we describe, the IOL remained stable 11 months following transscleral suture fixation at the desired axis., (Copyright © 2015 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Purpose: To demonstrate that ultrasound biomicroscopy (UBM) can be used for objective quantitative measurements of anterior segment accommodative changes., Setting: College of Optometry, University of Houston, Houston, Texas, USA., Design: Prospective cross-sectional study., Methods: Anterior segment biometric changes in response to 0 to 6.0 diopters (D) of accommodative stimuli in 1.0 D steps were measured in eyes of human subjects aged 21 to 36 years. Imaging was performed in the left eye using a 35 MHz UBM (Vumax) and an A-scan ultrasound (A-5500) while the right eye viewed the accommodative stimuli. An automated Matlab image-analysis program was developed to measure the biometry parameters from the UBM images., Results: The UBM-measured accommodative changes in anterior chamber depth (ACD), lens thickness, anterior lens radius of curvature, posterior lens radius of curvature, and anterior segment length were statistically significantly linearly correlated with accommodative stimulus demands. Standard deviations of the UBM-measured parameters were independent of the accommodative stimulus demands (ACD: 0.0176 mm; lens thickness: 0.0294 mm; anterior lens radius of curvature: 0.3350 mm; posterior lens radius of curvature: 0.1580 mm; and anterior segment length: 0.0340 mm). The mean difference between the A-scan and UBM measurements was -0.070 mm for ACD and 0.166 mm for lens thickness., Conclusions: Accommodating phakic eyes imaged using UBM allowed visualization of the accommodative response, and automated image analysis of the UBM images allowed reliable, objective, quantitative measurements of the accommodative intraocular biometric changes., Financial Disclosure: Neither author has a financial or proprietary interest in any material or method mentioned., (Copyright © 2015 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Purpose: To evaluate longitudinal changes in Implantable Collamer Lens phakic intraocular lens (pIOL) position after implantation., Setting: Department of Ophthalmology, Zhejiang University, Hangzhou, China., Design: Retrospective case series., Methods: Myopic eyes that had pIOL implantation with a follow-up of at least 24 months were evaluated. Ultrasound biomicroscopy examinations were performed at each visit., Results: The study enrolled 62 eyes (31 patients; 22 women, 9 men) ranging in age from 21 to 46 years. The manifest spherical equivalent ranged from -8.25 to -18.75 diopters. A significant increase (mean 36 μm±50 [SD]) in the endothelium-anterior pIOL distance occurred between 1 month and 3 months (P=.000); afterward, the distance decreased slowly (P>.05). The largest decrease (mean 47±17 μm) in central vault occurred between 1 month and 3 months (P=.009). The largest decrease (mean 21±14 μm) in peripheral vault occurred between 1 month and 3 months (P=.000)., Conclusions: A significant increase in the endothelium-anterior pIOL distance occurred from 1 month to 3 months postoperatively, after which a slight decrease occurred over time. Central vault and peripheral vault had a tendency to decrease over time., Financial Disclosure: No author has a financial or proprietary interest in any material or method mentioned., (Copyright © 2014. Published by Elsevier Inc.)

We propose 2 mechanisms of uveitis-glaucoma-hyphema (UGH) syndrome in 2 patients with intracapsular or in-the-bag single-piece acrylic intraocular lenses (IOLs). In the first case, pseudophacodonesis secondary to zonular laxity from pseudoexfoliation syndrome caused chafing of the posterior iris by the square-edged haptic. In the second case, focal capsular fibrosis around the square-edged haptics combined with anteriorly rotated ciliary processes in plateau iris configuration caused points of chafing. Extensive capsular fibrosis of the haptic in both cases precluded IOL exchange. In the first case, a capsular tension ring redistributed zonular tension and reduced symptoms. In the second case, endoscopic cyclophotocoagulation relieved areas of chafing and resolved symptoms. In-the-bag square-edged haptics of single-piece acrylic IOLs are a potential source of iridociliary chafing in certain situations. The mechanisms observed here should be considered to promptly diagnose and treat UGH., (Copyright © 2014 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Unlabelled: We describe a modified technique of black diaphragm intraocular lens (IOL) implantation in eyes with traumatic aniridia, aphakia, and previous vitrectomy. During black diaphragm IOL implantation, a double-armed 10-0 polypropylene suture is used to fixate the IOL in the ciliary sulcus. Two 10-0 polypropylene sutures are subsequently placed in front of the IOL to block its forward displacement and thus prevent its contact with the anterior chamber angle and corneal endothelium. This modified implantation technique reduces long-term complications following black diaphragm IOL implantation in patients with traumatic aniridia., Financial Disclosure: No author has a financial or proprietary interest in any material or method mentioned., (Copyright © 2013 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Purpose: To evaluate anterior segment variations after posterior chamber phakic intraocular lens (pIOL) implantation in myopic eyes., Setting: Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China., Design: Cohort study., Methods: Patients with high myopia were scheduled for nontoric Implantable Collamer Lens pIOL or toric Implantable Collamer Lens pIOL implantation. Anterior segment optical coherence tomography was performed to evaluate the anterior segment variations over time and the impact of physiologic accommodation and change in brightness after pIOL implantation. Slitlamp photography of the anterior segment was taken after pupil dilation to calculate pIOL rotation., Results: There was significantly improved visual acuity and refractive status after implantation of both pIOLs. Anterior segment axial variations had good stability 6 months postoperatively. However, nontoric pIOL rotation occurred in 1 eye 7 months postoperatively and rotation of the toric pIOL occurred in 2 eyes at 3 months and 6 months. Stimulations of -4.0 diopters (D) and -8.0 D led to significant changes in anterior chamber depth (ACD) based on the lens (ACD-lens), ACD after pIOL implantation, distance between the pIOL posterior surface and the lens anterior surface (pIOL-lens), and pupil diameter. Increasing ambient light brightness could reduce the ACD-lens and pIOL-lens., Conclusions: Both pIOLs had good axial stability in myopic eyes 6 months postoperatively; however, rotational stability over time could not be determined. The physiologic adjustment and change in brightness could influence the anterior segment significantly in eyes with a pIOL., (Copyright © 2013 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Purpose: To evaluate the stability and capsular bag opacification with a modified disk-shaped 1-piece hydrophilic acrylic intraocular lens (IOL) suspended between 2 complete haptic rings connected by a pillar of the haptic material and with a commercially available 1-piece hydrophilic acrylic IOL., Setting: John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA., Design: Experimental study., Methods: Study and control IOLs were implanted into the left eyes and right eyes of 5 New Zealand rabbits. Eyes were examined at the slitlamp from 1 through 4 weeks. At 4 weeks, the globes were enucleated and evaluated under a very-high-frequency ultrasound. Photographs were taken and capsular bag opacification scored from the posterior aspect (Miyake-Apple view), and the eyes were processed for complete histopathology., Results: At 4 weeks, the posterior capsule opacification score was 0.0 in the study group and 1.75 ± 0.5 (SD) in the control group (P=.005, paired t test). Ultrasound examination showed that 2 of the study IOLs had no contact between the posterior optic surface and the posterior capsule. Minimal proliferative cortical material was confined to the peripheral space between anterior and posterior rings of the study IOL haptics in localized areas at the equatorial region of the capsular bag. Anterior capsule opacification was absent in all eyes., Conclusions: The study IOL is a modification of a previous design, incorporating haptic perforations between the peripheral rings. By maintaining an open capsular bag and enhancing endocapsular inflow of aqueous, this modified design appears to prevent capsular bag opacification., (Copyright © 2012 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

We analyzed an enucleated postmortem eye from an 86-year-old donor who had a 2-loop iridocapsular intraocular lens (IOL) that had been implanted at least 30 years earlier. High-frequency ultrasound showed a relatively well-centered iris-supported optic in front of the pupil. Gross and light microscopic analyses of the eye and the IOL showed loop fixation outside the capsular bag remnants, a thickened cornea, mild attenuation of the corneal endothelium, multiple areas of iris trauma secondary to haptic abrasion, fragments of iris tissue attached to the haptics, as well as pigment dispersion within the eye with pigmented epithelial cells attached to the IOL haptics. Histopathological examination of the posterior segment was unremarkable., (Copyright © 2011 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Purpose: To assess the efficacy and safety of implanting a secondary intraocular lens (IOL) in the ciliary sulcus to correct pseudophakic ametropia., Setting: Department of Ophthalmology, Medical University of Vienna, Vienna, Austria., Methods: This prospective nonrandomized study included patients who had implantation of a secondary IOL (Sulcoflex 653L) to correct residual refractive error after phacoemulsification with IOL implantation in the capsular bag. After implantation of the secondary IOL in the ciliary sulcus, visual and refractive outcomes were evaluated. Inflammation was measured with a laser flare-cell meter. The position and rotation of the IOLs were documented at all control visits, and Scheimpflug images were taken. Postoperative follow-up was at 1 week and 1, 6, 12, and 17 months., Results: Twelve eyes of 10 patients were evaluated. The mean spherical equivalent decreased from -1.25 diopters (D) +/- 0.25 (SD) (range -2.00 to +4.00 D) preoperatively to -0.25 +/- 0.40 D (range -0.50 to +0.25 D) postoperatively. Uncorrected distance visual acuity improved in all cases. There were no significant intraoperative or postoperative complications., Conclusions: Sulcus implantation of the secondary IOL to correct pseudophakic refractive error was safe and predictable. The IOL was well tolerated in all eyes., Financial Disclosure: Neither author has a financial or proprietary interest in any material or method mentioned. Additional disclosures are found in the footnotes., (Copyright 2010 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Purpose: To evaluate the anatomic location of the haptic and optic of single-piece sulcus-fixated intraocular lenses (IOLs) and their proximity to the iris and ciliary body using ultrasound biomicroscopy (UBM)., Setting: Iladevi Cataract & IOL Research Center, Ahmedabad, India., Methods: This retrospective study comprised eyes that had primary sulcus implantation of a single-piece IOL. Eyes had an intact anterior capsulorhexis that could provide uniform IOL support and a preoperative anterior chamber depth (ACD) greater than 2.7 mm. The fixation site of the haptics, distance between the optic edge and iris, optic tilt, anterior chamber angle (ACA), central ACD, and ciliary body edema were evaluated by UBM., Results: The time from surgery to UBM examination was 7 to 85 months. Both haptics were in the sulcus in 7 of the 10 eyes, 1 haptic was abutting the iris and the other was in the sulcus in 2 eyes, and both haptics were embedded in ciliary body in 1 eye. The mean distance between the optic edge and iris was 0.16 mm +/- 0.07 (SD), 0.15 +/- 0.03 mm, and 0.38 mm, respectively. The mean ACA was 40.2 +/- 4.5 degrees (range 30.9 to 45.2 degrees), 34.1 +/- 4.5 degrees, and 44.1 degrees, respectively. The mean ACD was 3.47 +/- 0.24 mm, 3.50 +/- 0.23 mm, and 3.57 mm, respectively. No eye had optic tilt or ciliary body edema., Conclusions: Implantation of both haptics in the sulcus was not achieved in all eyes. The haptics and optics remained in close proximity to the posterior iris surface., ((c) 2010 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Purpose: to evaluate the results of intraocular lens (IOL) exchange in cases of severe negative dysphotopsia and to measure the distance between the iris and the IOL optic using ultrasound biomicroscopy (UBM)., Setting: Szent Rókus Hospital and Eye Clinic, Semmelweis University, Budapest, Hungary., Methods: Data of patients with major negative dysphotopsia symptoms after phacoemulsification with IOL implantation were reviewed retrospectively. In cases in which IOL exchange was performed to diminish the symptoms, the distance between the iris and the anterior surface of the IOL optic was measured by UBM and compared with that in a group of nonsymptomatic pseudophakic patients (control group)., Results: in 3806 cataract procedures, 5 eyes (4 patients) had severe negative dysphotopsia symptoms. Intraocular lens exchange was performed in 3 cases. In 1 case, the secondary IOL was implanted in the reopened capsular bag and the symptoms persisted. In 2 cases, the secondary IOL was implanted in the ciliary sulcus and the symptoms resolved. On UBM, the mean iris-optic distance was 0.45 mm +/- 0.07 (SD) in the symptomatic group, 0.59 +/- 0.29 mm in the control group (n = 21) (P = .353), and 0.00 mm in the sulcus-fixated group., Conclusions: The iris-optic distance was not statistically significantly different between eyes with severe negative dysphotopsia symptoms and nonsymptomatic eyes. However, when IOL exchange reduced the iris-IOL distance, the severe negative dysphotopsia symptoms resolved., (Copyright 2010 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.)

Purpose: To investigate the role of ultrasound biomicroscopy (UBM) in the evaluation of anterior segment anatomy in cases of congenital and developmental cataract., Setting: Alexandria Main University Hospital, Ophthalmology Department, Faculty of Medicine, Alexandria University, Alexandria, Egypt., Methods: In this cross-sectional nonrandomized unmasked study, ultrasound biomicroscopy (UBM) was used to evaluate the anterior segment anatomy of 32 eyes of 21 children with congenital and developmental cataract. The parents were questioned for details of the children's history. An initial office examination was done to detect visual function, pupil color, lens morphology, corneal clarity, and presence of gross anterior segment anomaly. If the fundus was visible, it was examined in cooperative children after mydriasis. Under general anesthesia, each child was examined by UBM., Results: The parameters detected by UBM included anterior chamber depth, lens thickness, zonular fiber length, ciliary process length, anterior chamber angle, and lens morphology. A-scan biometry was also performed to detect anterior chamber biometric characteristics., Conclusion: Ultrasound biomicroscopy is a valuable tool for evaluating childhood cataracts and associated ocular anomalies as well as anterior segment biometric characteristics.

Postoperative fibrin pupillary-block glaucoma, an uncommon complication of intraocular surgery, develops when an inflammatory fibrin membrane occludes the pupil, resulting in peripheral angle closure. We present a series of 4 patients with this condition and describe the role of anterior segment optical coherence tomography and ultrasound biomicroscopy in distinguishing fibrin pupillary-block glaucoma from other forms of postoperative acute glaucoma. Specific to this condition is the presence of a fibrin membrane across the pupil and accumulation of aqueous in the posterior chamber, as would be expected in pupil block, but with a clear separation between the intraocular lens and the iris. The possible risk factors are discussed and various treatment modalities reviewed.

Purpose: To determine the biometry of ocular structures and corneal topographic characteristics in patients with Weill-Marchesani syndrome., Setting: Department of Ophthalmology, Shiraz University of Medical Sciences, Shiraz, Iran., Methods: Patients with Weill-Marchesani syndrome (syndrome group) and age-matched normal subjects (control group) were evaluated. All had a complete ocular examination including refraction and analysis using Fourier transformation, slitlamp biomicroscopy, pachymetry, keratometry, and ocular biometry. The following A-scan parameters were measured: anterior chamber depth (ACD), lens thickness, axial length (AL), lens-AL factor, and relative lens position (RLP). Corneal topography examinations were performed in the syndrome group only., Results: The syndrome group comprised 7 female patients and the control group, 20 female subjects. The syndrome group had statistically significantly higher myopia and corneal astigmatism than the control group (P<.0001). Oblique astigmatism was common in the syndrome group, showing a strong right-left specificity (right eyes' axes in the 135-degree meridian, left eyes' axes in the 45-degree meridian). The syndrome group had a statistically significantly shorter AL, shallower ACD, thicker lens, higher calculated lens power, and a higher lens-AL factor (P<.0001). However, there was no statistically significant difference in RLP (P = .32). The syndrome group also had statistically significantly thicker corneas and higher keratometry values (P<.0001)., Conclusion: Characteristic ocular findings in patients with Weill-Marchesani syndrome were a steep, thick cornea with a strong right-left specificity of corneal astigmatism; a thick lens; a short AL; and a shallow ACD.

Purpose: To compare ab interno and ab externo scleral fixation of posterior chamber intraocular lenses (PC IOLs) using ultrasound biomicroscopy (UBM) to determine the centration of IOL optic and the position of the haptics in relation to the sulcus., Setting: Kasr Eleini Hospital, Cairo University, Cairo, Egypt., Methods: Consecutive patients with aphakia had ab externo or ab interno scleral fixation of a PC IOL. Ultrasound biomicroscopy was used preoperatively to determine whether the eyes were unsuitable for capsule fixation and 3 and 6 months postoperatively, determine the position of the haptics in relation to the ciliary sulcus, and evaluate centration of the optic., Results: Fifteen eyes of 14 patients were studied. Eight patients had ab externo fixation, and 7 had ab interno fixation. The haptics were located in the sulcus in 31% of cases with ab externo fixation and 29% with ab interno fixation. The difference was not statistically significant., Conclusion: Ab interno and ab externo scleral fixation, which are both blind procedures, resulted in comparable low rates of sulcus fixation.

Purpose: To evaluate 2-year postsurgical safety and efficacy of canaloplasty (circumferential viscodilation and tensioning of the inner wall of Schlemm canal) to treat open-angle glaucoma (OAG)., Setting: Multicenter surgical sites., Methods: This international prospective study comprised adult OAG patients having glaucoma surgery or combined glaucoma-cataract surgery. Qualifying preoperative intraocular pressure (IOP) was at least 16 mm Hg and historical IOP, at least 21 mm Hg. The full circumference of the canal was viscodilated and a trabecular tensioning suture placed with a microcatheter. Primary outcome measures included IOP and glaucoma medication use., Results: At 24 months, all 127 eyes (127 patients) had a mean IOP of 16.0 mm Hg +/- 4.2 (SD) and mean glaucoma medication use of 0.5 +/- 0.8 (baseline values 23.6 +/- 4.8 mm Hg and 1.9 +/- 0.8 medications). Eyes with canaloplasty alone had a mean IOP of 16.3 +/- 3.7 mm Hg and 0.6 +/- 0.8 medications (baseline values 23.2 +/- 4.0 mm Hg and 2.0 +/- 0.8 medications). Eyes with combined glaucoma-cataract surgery had a mean IOP of 13.4 +/- 4.0 mm Hg and 0.2 +/- 0.4 medications (baseline values 23.1 +/- 5.5 mm Hg and 1.7 +/- 1.0 medications). The IOP and medication use results at all time points were statistically significant versus baseline (P <.001). The late postoperative follow-up identified 3 patients with elevated IOP. No other serious ocular or nonocular complications were reported., Conclusion: Canaloplasty was safe and effective in reducing IOP in adult patients with OAG.

We analyzed an enucleated eye obtained postmortem from an 86-year-old donor who had been implanted with a hydrophilic acrylic bag-in-the-lens 4 months earlier. To our knowledge, this is the first donor eye implanted with this design to undergo pathological analysis. High-frequency ultrasound showed a well-centered IOL, fixated at the level of the capsular bag. Gross and light microscopic analyses of the eye showed that if anterior and posterior capsule openings are well stretched around the optic of this IOL design, proliferative/regenerative material is potentially confined to the intercapsular space of the capsular bag remnant outside the optic rim.

Purpose: To study the incidence, course, and common factors of patients with negative dysphotopsia and consider the possible role of the corneal incision in cases in which symptoms are transient., Setting: Private practice and the University of Cincinnati, College of Medicine, Cincinnati, Ohio, USA., Methods: Phacoemulsification with implantation of a single-piece acrylic intraocular lens (IOL) was performed in 250 consecutive routine cataract procedures. Patients were asked whether they noticed a temporal shadow on the day after surgery and were followed by serial evaluations for 3 years. Evaluations included subjective questionnaires and objective testing., Results: The incidence of negative dysphotopsia was 15.2% on the first postoperative day, decreasing to 3.2% after 1 year, then 2.4% after 2 and 3 years. Common findings included a shallow orbit, prominent globe, space greater than 0.45 mm between the iris and IOL by ultrasound biomicroscopy, and perimetric comet-shaped light in the area corresponding to the shadow. Slitlamp revealed a transparent peripheral capsule and a shadow sign in which a linear shadow on the iris became curvilinear as the light from the slit beam was projected through the incision toward the pupil., Conclusions: Two groups of patients experienced negative dysphotopsia that rapidly resolved or remained unchanged from the first postoperative day. It is hypothesized that the corneal edema associated with a beveled temporal incision contributes to transient negative dysphotopsia.

After uneventful phacoemulsification and in-the-bag implantation of an AcrySof SA60AT (Alcon) intraocular lens (IOL), a 52-year-old black man developed pigmentary glaucoma. Slitlamp examination, anterior segment optical coherence tomography, and ultrasound biomicroscopy showed that the posterior surface of the iris was being rubbed by the inferior haptic of the IOL, which was in the bag but deformed. Filtering surgery was needed to control the intraocular pressure. This type of IOL can cause IOL-induced pigmentary glaucoma.

Purpose: To evaluate meridional differences in angle-to-angle (A-A) and sulcus-to-sulcus (S-S) dimensions in human eyes using very high frequency ultrasound (VHF US) and anterior segment optical coherence tomography (AS-OCT)., Setting: John A. Moran Eye Center, University of Utah, USA; Berlin Eye Research Institute, Germany; Quattroelle Centri Oftalmochirurgici, Italy., Methods: Human autopsy eyes were fixated to special eye holders and had anterior segment scanning using 50 MHz ultrasound (Artemis, Ultralink) (20 eyes) and AS-OCT (SL-OCT, Heidelberg Engineering) (24 eyes). Seventy-three eyes (58 patients) also had anterior segment scanning using the same systems (Artemis, 50 eyes; SL-OCT, 23 eyes). Four meridians were evaluated in each eye. The A-A dimensions were measured by VHF US and AS-OCT. The S-S dimensions were also measured by VHF US. Statistical analyses were done with the Huynh-Feldt test., Results: In the autopsy-eye study, the differences in A-A and S-S dimensions between the 4 meridians in eyes analyzed with VHF US were statistically significant (P=.002 and P=.009, respectively). The differences in A-A dimensions in eyes analyzed with the AS-OCT were also significant (P=.005). The same findings were observed in the clinical study (VHF US, P=.001 for A-A and P<.001 for S-S; AS-OCT, P<.001 for A-A)., Conclusions: This study suggests that the internal geometry of the anterior segment of human eyes does not constitute a circle. This may have significant relevance for the accurate sizing of phakic intraocular lenses.

Purpose: To analyze anterior segment structure changes during accommodative stimuli after monofocal intraocular lens (IOL) implantation using 2 ultrasound biomicroscopy (UBM) systems., Setting: Department of Ophthalmology, University of Verona, Verona, Italy., Methods: Twenty-six eyes (23 patients) with 1 of 4 monofocal IOL types were studied. Five to 9 months postoperatively, the patients were examined by high-frequency UBM using the HiScan system (Optikon 2000 SpA) and UBM 840 system (Carl Zeiss Meditec). Anterior chamber depth (ACD), iris-zonule distance, anterior chamber angle (ACA), scleral-ciliary process angle, and iris-ciliary process angle were measured using both systems. The iris-ciliary process distance and scleral spur perpendicular-sulcus distance were measured with the UBM 840 system and the sulcus-sulcus distance and capsular bag-IOL position with respect to ciliary process apex, with the HiScan system. Two experienced examiners performed all measurements., Results: All parameters except the horizontal iris-ciliary process distance and vertical ACA measured by the UBM 840 system and horizontal ACA by the HiScan system showed significant variation during accommodation. An anterior shift of the IOL-capsular bag ciliary processes--sulcus-zonular iris complex was observed. A simultaneous centripetal shift of ciliary bodies and processes, shown by a reduction in sulcus and capsular bag diameter, was also observed., Conclusion: Anterior segment structures demonstrated accommodative movement on UBM after implantation of standard monofocal IOLs.

An enucleated eye obtained post-mortem from a 95-year-old donor who had a 4-loop, iris-fixated (iris-clip) glass intraocular lens (IOL) that had been implanted 22 years earlier was analyzed. The patient had a history of mild corneal edema, glaucoma, and macular degeneration/macular pucker. High-frequency ultrasound showed a well-centered iris-fixated IOL. Gross and light microscopic analyses of the eye and the IOL showed fragments of iris tissue attached to the haptics, pigment dispersion within the eye, with pigmented epithelial cells attached to the lens haptics and interruptions of the iris pigmented epithelial layers, and signs of corneal decompensation.

Purpose: To study prospectively the safety and pressure-reducing efficacy of the Y-shaped Eyepass glaucoma implant (GMP Vision Solutions, Inc.)., Setting: Departments of Ophthalmology, University of Cologne, Cologne, and University of Erlangen, Erlangen, Germany., Methods: This study comprised 12 patients with primary open-angle or exfoliative glaucoma and cataract who had phacoemulsification with endocapsular implantation of a foldable intraocular lens and intracanalicular implantation of an Eyepass glaucoma implant. The implant is a silicone microtube shunt that bypasses the trabecular meshwork and connects the lumina of Schlemm canal with the anterior chamber in combined cataract-glaucoma surgery. Perioperative complications, intraocular pressure (IOP), and pressure-reducing topical medications were monitored over a preliminary follow-up., Results: Perforation of the trabecular meshwork during Eyepass implantation occurred in 2 eyes; the antiglaucoma procedure was converted to trabeculotomy after the shunt was explanted, and both eyes were excluded from further follow-up. In the remaining 10 eyes, the mean maximum IOP was 30.4 mm Hg +/- 7.5 (SD) (range 21 to 46 mm Hg) preoperatively, 12.0 +/- 6.1 mm Hg (range 2 to 20 mm Hg) 1 day postoperatively, 17.2 +/- 4.1 mm Hg (range 12 to 27 mm Hg) at 4 weeks, and 18.3 +/- 4.5 mm Hg (range 12 to 25 mm Hg) at the end of the preliminary follow-up. The mean number of topical medications was 3.2 +/- 0.8 preoperatively and 0.9 +/- 0.7 at the end of follow-up (mean 7.1 months). Although there were no major complications requiring surgical revision, 4 eyes had an IOP of 18 or higher at the end of follow-up., Conclusion: Combined cataract surgery with Eyepass shunt implantation was safe and appeared to be beneficial in glaucomatous eyes with cataract not requiring a low target IOP.

Purpose: To determine the interchangeability of 2 anterior segment imaging systems: a very-high-frequency (VHF) ultrasound scanning system (Artemis 2, Ultralink LLC) and an optical coherence tomography (OCT) system (Visante, Zeiss)., Setting: Vissum Instituto Oftalmologico de Alicante, Alicante, Spain., Methods: This study comprised 20 eyes without pathology or previous surgery. The anterior chamber depth (ACD), central corneal thickness (CCT), angle-to-angle distance (ATA), and the iridocorneal angle size (IAS) at the 0-degree and 180-degree positions were measured with 2 imaging techniques: VHF ultrasound scanning and OCT. Analysis of agreement and interchangeability was performed by the Bland and Altman method. In addition, each measurement was performed 3 times consecutively to determine intrasession repeatability by means of the coefficient of variation (CV) and the intraclass correlation coefficient (ICC)., Results: No statistically significant differences were found between imaging techniques in ACD, CCT, or ATA (P>.40). The ranges of agreement were 0.20 mm, 16.11 mum, and 0.80 mm for ACD, CCT, and ATA, respectively. Regarding IAS, no statistically significant differences were found in the nasal (P = .78) or temporal (P = .63) measurements between devices. However, the range of agreement for nasal (14.3 degrees) and temporal (14.90 degrees) values was relevant, indicating the 2 techniques cannot be used interchangeably for IAS measurement. Excellent intrasession repeatability scores were obtained (CV and ICC)., Conclusion: The Artemis 2 and the Visante OCT systems provide equivalent and repeatable measurements of the ACD, CCT, and ATA and can be used interchangeably for these purposes.

Purpose: To compare the comfort levels and measurement accuracy of the open-shell technique and a bag/balloon technology (ClearScan, ESI) in anterior segment ultrasound biomicroscopy., Setting: Department of Ophthalmology and Visual Science, Robert Cizik Eye Clinic, University of Texas Medical School at Houston, Houston, Texas, USA., Methods: In this prospective investigation, 20 subjects stated their preference and rated comfort (0 best to 5 worst) for the open-shell technique versus the bag/balloon technology. Three anterior chamber depth and sulcus-to-sulcus measurements were obtained, and the mean for each structure was taken as datum for each subject. Order presentation between the 2 methods was randomized. Pairwise t tests and linear regression analysis were used to determine statistical differences., Results: One hundred percent of the cohort preferred the bag/balloon technology to the traditional open-shell technique. The mean comfort score was 0.40 +/- 0.53 (SD) and 2.95 +/- 0.90, respectively (P<.0001). Anterior chamber depth measurements did not differ clinically (0.056 mm) nor did sulcus-to-sulcus determinations (0.039 mm)., Conclusion: Biometry, patient comfort, and ease of use were better with the ClearScan bag/balloon technology than with the traditional open-shell technique.

Purpose: To compare anterior segment parameters using quantitative imaging by anterior segment optical coherence tomography (AS-OCT) and ultrasound biomicroscopy (UBM)., Setting: Tertiary-care glaucoma research center., Methods: Sixty-three eyes of 63 subjects had anterior segment evaluation by AS-OCT (Visante-Zeiss) and UBM (Paradigm). Central corneal thickness (CCT), anterior chamber depth (ACD) (measured from the central corneal endothelium to the anterior lens capsule), and the peripheral iridocorneal angles (temporal and nasal) were assessed and compared., Results: There was an excellent correlation between AS-OCT and UBM measurements for the nasal angle (r = 0.84; P<.0001), temporal angle (r = 0.86; P<.0001), ACD (r = 0.97; P<.0001), and CCT (r = 0.91; P<.0001). There was no significant difference (paired t test) between the mean ACD, CCT, and angle parameters measured by AS-OCT or UBM. The mean values of the parameters measured by AS-OCT and UBM were, respectively, as follows: nasal angle, 26.25 degrees +/- 11.0 (SD) and 28.27 +/- 11.3 degrees (P = .3); temporal angle, 25.1 +/- 11.4 degrees and 28.3 +/- 13.5 degrees (P = .15); ACD, 2.85 +/- 0.5 mm and 2.78 +/- 0.5 mm (P = .2); and CCT, 512 +/- 46 microm and 502 +/- 46 microm (P = .25). The AS-OCT images showed sharper definition of the scleral spur than the UBM images., Conclusion: Anterior segment optical coherence tomography and UBM can both be used for anterior segment measurements and yielded comparable results.

We describe a pseudophakic patient with pseudoexfoliation who developed late intraocular lens (IOL) instability manifested by pseudophakodonesis, a change in refraction, and loss of glaucoma control. The patient subsequently required glaucoma surgery that was complicated by vitreous loss. Preoperative ultrasound biomicroscopy (UBM) failed to provide useful information regarding the zonular status. The patient died as a result of a malignancy, and the eye was donated for research. Anatomical evaluation confirmed the clinical impression of IOL placement in the bag and zonular laxity. Postmortem UBM helped explain some of the technical difficulties in examining zonules in the pseudophakic state.

Purpose: To determine the accuracy, repeatability, and reproducibility of measurement of lateral dimensions using the Artemis (Ultralink LLC) very high-frequency (VHF) digital ultrasound (US) arc scanner., Setting: London Vision Clinic, London, United Kingdom., Methods: A test object was measured first with a micrometer and then with the Artemis arc scanner. Five sets of 10 consecutive B-scans of the test object were performed with the scanner. The test object was removed from the system between each scan set. One expert observer and one newly trained observer separately measured the lateral dimension of the test object. Two-factor analysis of variance was performed. The accuracy was calculated as the average bias of the scan set averages. The repeatability and reproducibility coefficients were calculated. The coefficient of variation (CV) was calculated for repeatability and reproducibility., Results: The test object was measured to be 10.80 mm wide. The mean lateral dimension bias was 0.00 mm. The repeatability coefficient was 0.114 mm. The reproducibility coefficient was 0.026 mm. The repeatability CV was 0.38%, and the reproducibility CV was 0.09%. There was no statistically significant variation between observers (P = .0965). There was a statistically significant variation between scan sets (P = .0036) attributed to minor vertical changes in the alignment of the test object between consecutive scan sets., Conclusion: The Artemis VHF digital US arc scanner obtained accurate, repeatable, and reproducible measurements of lateral dimensions of the size commonly found in the anterior segment.