Parallel comparison of ocular metrics in non-human primates with high myopia by LS900, ultrasonography and MRI-based 3D reconstruction.

We investigate the ocular dimensions and shape by using Lenstar900 (LS900), A-scan ultrasonography, and Magnetic Resonance Imaging (MRI) in highly myopic Macaca fascicularis. The ocular dimensions data of LS900, A-scan ultrasonography and MRI was assessed from 8 eyes (4 adult male cynomolgus macaque) with extremely high myopia (≤-1000DS) and compared by means of coefficients of concordance and 95% limits of agreement. Multiple regression analysis was performed to explore the associations between ocular biometry, volume, refraction and inter-instrument discrepancies. Test-retest reliability of three measurements of ocular parameters at two time points was almost equal (intraclass correlation = 0.831 to 1.000). The parallel-forms reliability of three measurements was strong for vitreous chamber depth (VCD) (coefficient of concordance = 0.919 to 0.981), moderate for axial length (AL) (coefficient of concordance = 0.486 to 0.981), and weak for anterior chamber depth (ACD) (coefficient of concordance = 0.267 to 0.621) and lens thickness (LT) (coefficient of concordance = 0.035 to 0.631). The LS900 and MRI systematically underestimated the ACD and LT comparing to A-scan ultrasonography (P < 0.05). Notably, the average AL on LS900 displayed a significant correlation with those on MRI (r = 0.978, P < 0.001) and A-scan ultrasonography (r = 0.990, P < 0.001). Almost 4/5 eyeballs were prolate. The mean eyeball volume positively correlated with AL (r = 0.782, P = 0.022), the width (r = 0.945, P = 0.000), and the length (r = 0.782, P = 0.022) of eyeball, while negatively correlated with SER (r = -0.901, P = 0.000). In conclusion, there was a high inter-instrument concordance for VCD with LS900, A-scan ultrasonography and MRI, while ACD and LT were underestimated with LS900 compared to A-scan ultrasonography, and the LS900 and A-scan ultrasonography could reliably measure the AL. MRI further revealed an equatorial globe shape in extremely myopic non-human primates.

Optical coherence tomography for the screening of anterior chamber inflammation in paediatric patients diagnosed with juvenile idiopathic arthritis.

OBJECTIVES: To evaluate the effectiveness of the anterior segment optical coherence tomography (AS-OCT) for the screening of anterior uveitis in children diagnosed with juvenile idiopathic arthritis (JIA). METHODS: A cross-sectional, observational, non-randomised study was conducted in JIA patients younger than 18 years. All patients underwent anterior segment (AS-OCT) and macular OCT. RESULTS: A total of 300 eyes of 150 patients diagnosed with JIA were included; 74% were females, and mean age was 11.12 ± 3.51 years old (range 4.13-18.60). In the slit-lamp examination, anterior uveitis was diagnosed in 16 eyes. In the AS-OCT, anterior uveitis was suspected in 27 eyes; cells were detected in 27 eyes and retrokeratic precipitates in 5 eyes. Sensitivity was 0.94 and specificity was 0.96, positive predictive value was 0.59 and negative predictive value was 0.99, and Kappa-Cohen index was 0.71. CONCLUSIONS: AS-OCT could be considered for the screening of anterior segment uveitis in children diagnosed with JIA.

Predictability comparison of sizing parameters for postoperative vault after implantable Collamer lens implantation.

PURPOSE: This study aims to assess the accuracy of three parameters (white-to-white distance [WTW], angle-to-angle [ATA], and sulcus-to-sulcus [STS]) in predicting postoperative vault and to formulate an optimized predictive model. METHODS: In this retrospective study, a cohort of 465 patients (comprising 769 eyes) who underwent the implantation of the V4c implantable Collamer lens with a central port (ICL) for myopia correction was examined. Least absolute shrinkage and selection operator (LASSO) regression and classification models were used to predict postoperative vault. The influences of WTW, ATA, and STS on predicting the postoperative vault and ICL size were analyzed and compared. RESULTS: The dataset was randomly divided into training (80%) and test (20%) sets, with no significant differences observed between them. The screened variables included only seven variables which conferred the largest signal in the model, namely, lens thickness (LT, estimated coefficients for logistic least absolute shrinkage of -0.20), STS (-0.04), size (0.08), flat K (-0.006), anterior chamber depth (0.15), spherical error (-0.006), and cylindrical error (-0.0008). The optimal prediction model depended on STS (R2=0.419, RMSE=0.139), whereas the least effective prediction model relied on WTW (R2=0.395, RMSE=0.142). In the classified prediction models of the vault, classification prediction of the vault based on STS exhibited superior accuracy compared to ATA or WTW. CONCLUSIONS: This study compared the capabilities of WTW, ATA, and STS in predicting postoperative vault, demonstrating that STS exhibits a stronger correlation than the other two parameters.

Aqueous misdirection syndrome: clinical outcomes and risk factors for treatment failure.

PURPOSE: To evaluate the outcomes of postoperative aqueous misdirection and factors predicting failure of interventions. METHODS: This retrospective study included 49 eyes from 47 patients with aqueous misdirection following glaucoma or cataract surgery. Resolution of aqueous misdirection (AM) was deepening of the central anterior chamber (AC) and intraocular pressure (IOP) ≤ 21 mmHg. The Cox proportional hazards regression model was used to evaluate risk factors for failure of various treatments. RESULTS: 10/49 eyes (20%) resolved with conservative management, and 39/49 eyes (80%) needed multiple intervention, of which 95% (37/39) eyes achieved resolution of aqueous misdirection. Pseudophakia predicted the need for multiple interventions with a hazard ratio of 2.391 (1.158-4.935), p = 0.02). Among the risk factors assessed for resolution of AM, longer axial length (HR: 0.61 (0.414-0.891), p < 0.01) and eyes with prior glaucoma surgery predicted resolution (HR: 0.142 (0.027-0.741), p < 0.01) and delayed presentation predicted failure (HR: 1.002 (1.0002-1.0031), p < 0.02). CONCLUSION: Pseudophakic eyes were more refractory and predicted the need for multiple interventions. Eyes with prior glaucoma surgery and those with longer axial length had achieved resolution faster, and delayed presentation was a risk factor for failure to resolve.

Distribution and associations of anterior lens zonules lengths in patients with cataract.

PURPOSE: To investigate the characteristics and associations of anterior lens zonules lengths in cataract patients via ultrasound biomicroscope (UBM) measurement. METHODS: Patients with age-related cataracts and high myopic cataracts who planned to undergo cataract surgery were included in the study. After routine ophthalmic examinations, the UBM was performed on both eyes to get images of the anterior lens zonules, and Image J software was used to measure the lengths of the lens zonules. Axial length (AL), anterior chamber depth (ACD), lens thickness (LT), and white-to-white (WTW) diameter of both eyes were obtained by IOL Master 700. Univariate and multivariate regression analyses were used to assess associated factors of anterior lens zonules lengths. RESULTS: Forty-nine patients with age-related cataracts and 33 patients with high myopic cataracts were enrolled. High myopic cataract patients were younger and had longer anterior lens zonules. Multivariate regression analysis showed that anterior lens zonules lengths were associated with axial lengths (temporal location: ß = 0.036, P = 0.029; nasal location: ß = 0.034, P = 0.011; superior location: ß = 0.046, P = 0.002) and ACD (inferior location: ß = 0.305, P = 0.016) in right eyes. In left eyes, anterior lens zonules lengths were associated with axial lengths (temporal location: ß = 0.028, P = 0.017; inferior location: ß = 0.026, P = 0.016; nasal location: ß = 0.033, P < 0.001) and ACD (inferior location: ß = 0.215, P = 0.030; superior location: ß = 0.290, P = 0.011). CONCLUSIONS: High myopic cataract patients have longer anterior lens zonules. AL and ACD contributed to the lengths of anterior lens zonules. Thus, for patients with long AL and deeper ACD, lens zonules measurement was crucial. CLINICAL TRIAL REGISTRATION: www.chictr.org.cn identifier is ChiCTR2300071397.

Anterior chamber and angle characteristics in Chinese children (6-11 years old) with different refractive status using swept-source optical coherence tomography.

BACKGROUND: The anatomic structure of the anterior chamber (AC) helps to explain differences in refractive status in school-aged children and is closely associated with primary angle closure (PAC). The aim of this study was to quantify and analyze the anterior chamber and angle (ACA) characteristics in Chinese children with different refractive status by swept-source optical coherence tomography (SS-OCT). METHODS: In a cross-sectional observational study, 383 children from two primary schools in Shandong Province, China, underwent a complete ophthalmic examination. First, the anterior chamber depth (ACD), anterior chamber width (ACW), angle-opening distance (AOD), and trabecular-iris space area (TISA) were evaluated automatically using a CASIA2 imaging device. AOD and TISA were measured at 500, 750 µm nasal (N1 and N2, respectively), and temporal (T1 and T2, respectively) to the scleral spur (SS). Cycloplegic refraction and axial length (AL) were then measured. According to spherical equivalent refraction (SER), the children were assigned to hyperopic (SER > 0.50D), emmetropic (-0.50D < SER ≤ 0.50D), and myopic groups (SER ≤ -0.50D). RESULTS: Out of the 383 children, 349 healthy children (160 girls) with a mean age of 8.23 ± 1.06 years (range: 6-11 years) were included. The mean SER and AL were - 0.10 ± 1.57D and 23.44 ± 0.95 mm, respectively. The mean ACD and ACW were 3.17 ± 0.24 mm and 11.69 ± 0.43 mm. The mean AOD were 0.72 ± 0.25, 0.63 ± 0.22 mm at N1, T1, and 0.98 ± 0.30, 0.84 ± 0.27 mm at N2, T2. The mean TISA were 0.24 ± 0.09, 0.22 ± 0.09mm2 at N1, T1, and 0.46 ± 0.16, 0.40 ± 0.14mm2 at N2, T2. The myopic group had the deepest AC and the widest angle. Compared with boys, girls had shorter AL, shallower ACD, narrower ACW, and ACA (all p < 0.05). By Pearson's correlation analysis, SER was negatively associated with ACD, AOD, and TISA. AL was positively associated with ACD, ACW, AOD, and TISA. In the multiple regression analysis, AOD and TISA were associated with deeper ACD, narrower ACW, and longer AL. CONCLUSION: In primary school students, the myopic eyes have deeper AC and wider angle. ACD, ACW, AOD, and TISA all increase with axial elongation. ACA is highly correlated with deeper ACD.

Refraction and ocular biometric parameters in 3-to 6-year-old preschool children : a large-scale population-based study in Chengdu, China.

PURPOSE: To understand the ocular biometric parameters characteristics and refractive errors in 3-to 6-year-old preschool children in Chengdu, China, and to investigate the prevalence of refractive errors. METHOD: A school-based cross-sectional study was conducted in Chengdu from 2020 to2022 with a total of 666 kindergartens. All children were measured by non-cycloplegic autorefraction and uncorrected visual acuity (UCVA) and ocular biometric parameters. Finally, univariate linear regression models were used to analyze the relationship between ocular biometric parameters and refraction. RESULTS: A total of 108,578 preschool children aged 3-6 underwent examinations, revealing a myopia prevalence of 6.1%. The mean axial length (AL), keratometry (K), corneal radius (CR), axial length/corneal radius (AL/CR) Ratio, central corneal thickness (CCT), anterior chamber depth (ACD), lens thickness (LT), and vitreous chamber depth (VCD) were 22.35 ± 0.69 mm, 43.35 ± 1.58 D, 7.80 ± 0.28 mm, 2.87 ± 0.08, 533.31 ± 32.51 µm, 2.70 ± 0.28 mm, 3.91 ± 0.27 mm, and 15.20 ± 0.68 mm, respectively. With increasing age, AL, CR, AL/CR ratio, CCT, ACD, LT, and VCD also increased. Regardless of age, males consistently exhibited longer AL, flatter corneal curvature, shallower ACD, thicker CCT, thinner LT, and longer VCD compared to females. AL, K, CR, LT, and VCD all showed significant linear relationships with SE (all P < 0.001) in univariate linear regression analysis after adjusting for gender and age. CONCLUSION: The prevalence of myopia among preschool children aged 3-6 in Chengdu is relatively low. Ocular biometric parameters affecting refractive errors include AL, K, CR, LT, and VCD. The preschool period serves as a critical phase for myopia prevention and control.

Spontaneous Dislocation of the Lens Nucleus Into the Anterior Chamber Observed in a Patient With Overmature Senile Cataract.

Overmature cataract refers to the advanced stage of cataract where timely surgical intervention is not performed, leading to further progression characterized by decreased water content in the lens, degradation of fibers, and liquefaction within its structure, which can cause a reduction in volume, wrinkling of the capsule, as well as calcification or cholesterol crystallization on its surface. In addition, it may result in deepening of the anterior chamber. If left promptly untreated, these complications may result in visual impairment or even blindness. The occurrence of spontaneous complete dislocation of the lens nucleus into the anterior chamber in overmature cataracts is extremely uncommon. The authors present a case study involving a 74-year-old female patient who was diagnosed with complete dislocation of the lens nucleus in an overmature senile cataract without any apparent ocular injury or any relevant medical records. After undergoing cataract removal combined with anterior vitrectomy, the patient experienced relief from eye discomfort and expressed satisfaction with the surgical outcome; however, her visual acuity did not show significant improvement.

Estimation of angle parameters by ASOCT and biometric parameters by optical biometer in eyes with occludable angles and open angles.

PURPOSE: To compare anterior chamber angle (ACA) parameters measured by Anterior Segment Optical Coherence Tomography (ASOCT) and biometric parameters measured by Swept-Source (SS) OCT-based biometry among patients with suspected occludable angles and open angles. METHODS: An analytical, cross-sectional study was performed on subjects attending our ophthalmology outpatient department with suspected occludable angles (van Herick grades 0, 1, and 2) in group 1, and with open angles (van Herick grades 3 and 4) in group 2. Each subject underwent a complete ophthalmic examination to exclude any intraocular pathology like cataract. We recruited 128 eyes of 64 subjects, 34 in group 1 and 30 in group 2. Each eye was henceforth subjected to ASOCT (Spectralis, Heidelberg Engineering, Heidelberg) and SS-OCT-based optical biometry (IOL Master 700, Carl Zeiss Meditec AG). Anatomical parameters were recorded and compared between the two groups. RESULTS: The main outcome measures of the study included nine ASOCT parameters (central corneal thickness [CCT], lens vault, AOD750, ACA, TISA750 [nasal and temporal], and ACW) and five optical biometric parameters (CCT, ACD, WTW, LT, and axial length). We found a significant difference (p < 0.05) among all the anatomical parameters between the two groups, except CCT which was not significantly different (p = 0.297). CONCLUSIONS: ASOCT and SSOCT biometry overcome the challenges of gonioscopy and allow screening for angle closure disease in otherwise normal subjects. ASOCT may serve as an alternative to gonioscopy as it clearly separates occludable angles from open angles in a non-invasive and objective manner.

Evaluation of eye and serum findings in different waters in rabbits by drowning and submersion modeling.

Background/aim: This study investigated serum, vitreous, and anterior chamber fluid electrolyte changes, corneal thickness (CT), corneal volume (CV), anterior chamber volume (ACV), and anterior chamber depth (ACD) as an auxiliary diagnostic method in the identification of drowning in fresh or salt water. Materials and methods: The study used 35 healthy, adult, male, white New Zealand rabbits, seperated into five groups (control, saltwater drowning (SWD), saltwater immersion (SWI), freshwater drowning (FWD), freshwater immersion (FWI)). CT, CV, ACV, and ACD measurements were made with Pentacam topography at 0, 2, and 4 h in all groups. Magnesium (mg), sodium (Na), and chlorine (Cl) were measured in the blood at 0 and 2 h, and in blood, vitreous fluid, and humor aqueous at 4 h. Results: It was determined that CT, CV, ACV, and ACD are not of great value in drowning diagnosis and are affected by the fresh or salt water rather than drowning. Vitreous Na, Cl, and Mg levels are ineffective in determining drowning after one h. Anterior chamber fluid may provide valuable information in the differentiation freshwater - saltwater drownings at the 4th h in corpses retrieved from water. Conclusion: Anterior chamber fluid Na and Cl levels, especially in corpses removed from salt water, can be an easily used test that can help diagnose drowning.

Associations between corneal curvature and other anterior segment biometrics in young myopic adults.

To investigate the associations between corneal curvature (CC) and other anterior segment biometrics in young myopic adults. In this retrospective multi-center study, 7893 young myopic adults were included. CC and other anterior segment biometrics were measured by Scheimpflug imaging (Pentacam). CC was defined as SimK at central 3 mm area, and other anterior segment biometrics included white-to-white corneal diameter (WTW), central corneal thickness (CCT), corneal volume (CV) at 3 mm, 5 mm, and 7 mm area, anterior corneal astigmatism (ACA), posterior corneal astigmatism (PCA), anterior corneal eccentricity (ACE) and asphericity (ACAP), posterior corneal eccentricity (PCE) and asphericity (PCAP), anterior chamber depth (ACD), and anterior chamber volume (ACV). Univariate regression analyses were used to assess the associations between CC and other anterior segment biometrics, and multivariate regression analyses were further performed to adjusted for age, gender and spherical equivalent. CC was higher in patients of female gender and higher myopia (all P < 0.05). Eyes in higher CC quartiles had lower WTW, thinner CCT, lower CV at 3 mm and 5 mm, lower ACD, and lower ACV (all P < 0.001), but had larger ACA, larger PCA, less PCE and less PCAP (all P < 0.001), compared to eyes in lower CC quartiles. The trends of CV at 7 mm, ACE and ACAP were inconsistent in different CC quartiles. After adjusting for age, gender and spherical equivalent with multivariate linear regression, CC was positively correlated to CV at 7 mm (ßs = 0.069), ACA (ßs = 0.194), PCA (ßs = 0.187), ACE (ßs = 0.072), PCAP (ßs = 0.087), and ACD (ßs = 0.027) (all P < 0.05), but was negatively correlated to WTW (ßs = - 0.432), CCT (ßs = - 0.087), CV-3 mm (ßs = - 0.066), ACAP (ßs = - 0.043), PCE (ßs = - 0.062), and ACV (ßs = - 0.188) (all P < 0.05). CC was associated with most of the other anterior segment biometrics in young myopic adults. These associations are important for better understanding of the interactions between different anterior segment structures in young myopic patients, and are also useful for the exploration of the pathogenesis of myopia.

Influence of Ocular Biometric Parameters on Intraocular Lens Position: A Prospective Cohort Study.

PURPOSE: To assess the influence of ocular biometric parameters on intraocular lens (IOL) tilt and decentration after cataract surgery. METHODS: Patients scheduled for cataract surgery were screened for inclusion in this prospective cohort study. Tilt and decentration of the crystalline lens and IOL were measured using the CASIA2 (Tomey). Anterior chamber depth (ACD), lens thickness (LT), and axial length (AL) were preoperatively measured by the IOLMaster 700 (Carl Zeiss Meditec AG). Multivariate regression analysis was performed to assess the influence of ocular biometric parameters on IOL tilt and decentration after cataract surgery. RESULTS: In total, 191 eyes of 120 patients were included. Age was positively correlated with IOL tilt, whereas ACD and AL were negatively correlated with IOL tilt. A strong positive correlation was found between preoperative crystalline lenses and postoperative IOLs in tilt magnitude (r = 0.769, P < .001) and tilt direction (r = 0.688, P < .001). A positive correlation was found between preoperative and postoperative lens decentration magnitude and decentration direction. Greater postoperative IOL tilt and decentration were significantly associated with greater preoperative crystalline lens tilt (P < .001) and decentration (P = .027). CONCLUSIONS: IOL tilt was greater in older patients. Shorter AL and shallower ACD contributed to greater IOL tilt. The tilt and decentration of the IOL will be greater in patients with greater tilt and decentration of the crystalline lens. [J Refract Surg. 2024;40(7):e438-e444.].

Ocular Biometric Components in Hyperopic Children and a Machine Learning-Based Model to Predict Axial Length.

Purpose: The purpose of this study was to investigate the development of optical biometric components in children with hyperopia, and apply a machine-learning model to predict axial length. Methods: Children with hyperopia (+1 diopters [D] to +10 D) in 3 age groups: 3 to 5 years (n = 74), 6 to 8 years (n = 102), and 9 to 11 years (n = 36) were included. Axial length, anterior chamber depth, lens thickness, central corneal thickness, and corneal power were measured; all participants had cycloplegic refraction within 6 months. Spherical equivalent (SEQ) was calculated. A mixed-effects model was used to compare sex and age groups and adjust for interocular correlation. A classification and regression tree (CART) analysis was used to predict axial length and compared with the linear regression. Results: Mean SEQ for all 3 age groups were similar but the 9 to 11 year old group had 0.49 D less hyperopia than the 3 to 5 year old group (P < 0.001). With the exception of corneal thickness, all other ocular components had a significant sex difference (P < 0.05). The 3 to 5 year group had significantly shorter axial length and anterior chamber depth and higher corneal power than older groups (P < 0.001). Using SEQ, age, and sex, axial length can be predicted with a CART model, resulting in lower mean absolute error of 0.60 than the linear regression model (0.76). Conclusions: Despite similar values of refractive errors, ocular biometric parameters changed with age in hyperopic children, whereby axial length growth is offset by reductions in corneal power. Translational Relevance: We provide references for optical components in children with hyperopia, and a machine-learning model for convenient axial length estimation based on SEQ, age, and sex.

Consequences of Clot Formation and Hyphema Post-Internal Trabeculotomy for Glaucoma.

PRCIS: Clot formation and hyphema following internal trabeculotomy represent distinct clinical entities. The eyes with clot formation exhibited a more pronounced postsurgical intraocular pressure spike, longer residual intracameral bleeding, and a higher risk of reoperation. PURPOSE: The aim of this study was to investigate the consequences of clot formation and hyphema in the anterior chamber after internal trabeculotomy. MATERIALS AND METHODS: In this retrospective interventional comparative study, we investigated the surgical outcomes of internal trabeculotomy in 142 eyes of 142 patients at Sensho-kai Eye Institute. RESULTS: Concurrent clot formation and L≥2 hyphema (height of hyphema ≥1 mm) was observed in 22 eyes. In these cases, the postsurgical IOP was 29.3 mm Hg at 1 week, significantly higher than the 16.1 mm Hg in eyes that had L≥2 hyphema but without clot formation ( P =0.0002). However, the 1-week postsurgical IOP in L≥2 hyphema and clot (-) eyes, which measured 16.1 mm Hg was not significantly greater than that in L<2 hyphema and clot (-) eyes, which measured 18.7 mm Hg ( P =0.162). Thus, clot formation was identified as a significant factor contributing to high postsurgical IOP at 1 week. The resolution time for anterior chamber bleeding in eyes with concurrent clot formation and L≥2 hyphema was 12.3 days, longer than the 5.8 days observed in L≥2 hyphema eyes without clot formation ( P =0.016). Among the 22 eyes with concurrent L≥2 hyphema and clot formation, 8 required anterior chamber washout. Three of the 10 eyes that underwent washout necessitated additional trabeculectomy, a rate significantly higher than that in nonwashout eyes ( P <0.001). CONCLUSIONS: After internal trabeculotomy, the sequelae of concurrent clot formation and L≥2 hyphema in the anterior chamber were more severe than those of simple hyphema without clots. Clot formation negatively affected postoperative IOP.

Double trouble in DMEK surgery: Learning experience and review of the literature.

PURPOSE: To report a challenging Descemet Membrane Endothelial Keratoplasty (DMEK) case, complicated by intraoperative aqueous misdirection and spontaneous anterior chamber fibrin reaction. METHODS: A 70-year-old female affected by corneal edema due to Fuchs endothelial dystrophy underwent a triple procedure (cataract extraction - IOL implantation - DMEK surgery) in her left eye. This report illustrates the management of the intraoperative complications of aqueous misdirection syndrome and anterior chamber fibrin reaction. RESULTS: Despite the optimal management of the posterior pressure and the thorough removal of the fibrinous reaction during the case, the DMEK graft was not completely unfolded and centred at the end of the surgical procedure. Nonetheless, the patient showed good long-term anatomical and functional recovery: at the last follow-up (2 years after surgery), central corneal thickness was 526 µm with a best corrected visual acuity of 20/25 and an endothelial cell density of 1112 cell/mm2. CONCLUSION: Early recognition and prompt management of intraoperative aqueous misdirection syndrome and anterior chamber fibrin reaction during DMEK surgery is essential to ensure good functional and anatomical outcomes.

Iris atrophy following intracameral dexamethasone injection: a report of two pediatric cases.

We report 2 pediatric cases of iris atrophy that developed roughly 1 month after intracameral injection of dexamethasone suspension 9% following unilateral goniotomy and cataract extraction.

Long-term results of anterior chamber iris claw intraocular lens implantation in children with ectopia lentis in Marfan syndrome.

PURPOSE: To report the long-term clinical and endothelial cell count (ECC) results of lensectomy with primary anterior chamber iris claw lens implantation in the eyes of patients ≤18-year-old with ectopia lentis due to Marfan syndrome. METHODS: The medical records of Marfan patients operated on at a single institution from September 2007 to August 2020, with minimum follow-up of 2 years, were reviewed retrospectively. The following data were analyzed: sex, age at surgery, indication for surgery, the position of the lens in relation to the undilated and dilated pupil, corneal endothelial cell counts (ECC), peri- and postoperative complications, pre- and postoperative best-corrected visual acuity. RESULTS: A total of forty-two eyes of 23 patients (12 girls and 11 boys) were included. At least two or more postoperative ECCs were collected from 33 eyes (17 patients). Median age at IOL implantation was 6.1 years (range, 1.8-18). Median overall follow-up time was 6.2 years (range, 2-13.5). Median ECC follow-up time was 6.2 years (range, 2-10). Mean best-corrected visual acuity was 0.71 ± 0.38 logMAR before surgery and 0.02 ± 0.25 logMAR at final follow-up. The mean annual ECC decline was 0.71% ± 2.24. Total cell loss from first to last postoperative measurement was 150 cells ± 394 cells/mm2 (4.81%). Pre- and first postoperative data were available for 17 eyes of 10 patients, with a mean cell loss before and directly after surgery of 269 ± 268 cells (7.94%). Surgery related complications were iris bombé due to blockage of peripheral iridectomy in 3 eyes and claw dislocation due to direct impact trauma in 3 eyes. CONCLUSIONS: In our large, pediatric study cohort, anterior chamber iris claw IOL implantation resulted in an excellent visual outcome and normal endothelial cell loss compared with normative data. Safety measures are recommended to avoid traumatic dislocation of IOLs.

Comparison of the Biometric Characteristics After Long-term Implantation of Iris-fixated Phakic Intraocular Lens in Explanted and Nonexplanted Groups of Eyes.

PURPOSE: To evaluate and compare the biometric characteristics of the anterior chamber of a group of patients with significant endothelial cell loss (ECL) who required phakic intraocular lens (pIOL) explantation and a group of patients who did not fulfill the explantation criteria related to corneal decompensation. DESIGN: Retrospective, consecutive, interventional case series. METHODS: The study included all consecutive patients receiving a pIOL implantation at Oftalmosalud Instituto de Ojos, Lima, Peru, between 2001 and 2012. The explanted group (E group) consisted of eyes in which the pIOLs were explanted due to ECL, and the nonexplanted group (NE group) consisted of eyes randomly selected in which the pIOL was not explanted with a minimum follow-up time of 8 years. Slit-lamp biomicroscopy, visual acuity, refraction, endothelial cell count, and anterior segment optical coherence tomography were assessed at the preoperative evaluation for both groups and before explantation in the E group and 8 years post-implantation in the NE group. RESULTS: pIOLs were implanted in 265 eyes. The annual percentage of ECL was 1.47% and 5.55% in the NE group and E group, respectively (P < .001). The mean minimum endothelial lens distance (ELD) was 1.44 ± 0.22 mm and 1.05 ± 0.23 mm in the NE group and E group, respectively (P < 0.001). The mean time for explantation was 12.58 ± 3.79 years for the E group. Annual ECL could accurately discriminate between the NE group and E group; a cutoff point of 3.5 (%/year) or 86.5 (cells/years) had a 100% sensitivity and specificity. A cutoff of 1.21 mm in the minimum ELD has a 91% sensitivity and 79% specificity to discriminate between the E group and NE group. CONCLUSIONS: pIOL explantation due to ECL occurs in eyes with a significantly postoperative lower minimum ELD. Annual ECL and minimum ELC can effectively discriminate between the E and NE groups.

Direct observation and measurement of circumlental space and its relation to anterior chamber angle characteristics in iridotomized phakic eyes with primary angle closure disease.

Primary angle closure disease (PACD) is a major cause of blindness worldwide. It has a high prevalence in East Asia, especially in China, which leads to a higher incidence of blindness than open-angle glaucoma. The aim of this study was to directly observe the circumlental space (CLS) in laser peripheral iridotomized eyes with PACD and to determine whether this structure plays a role in the pathogenesis of PACD. Fifty eyes of 50 patients with PACD, who had received laser peripheral iridotomy performed with neodymium:yttrium-aluminum-garnet were recruited from glaucoma clinics from March 2021 to May 2022, including 17 primary angle closure suspect (PACS), 16 primary angle closure (PAC) and 17 primary angle closure glaucoma (PACG). They were classified into two groups based on whether the ciliary process and the crystalline lens equator were in contact using slit-lamp photograph: the attached group and the unattached group. The demographic, clinical characteristics and anterior segment parameters measured from ultrasound biomicroscopy were compared between the attached group and the unattached group. Thirty-three eyes were assigned to the attached group and 17 eyes belonged to the unattached group. In the unattached group, the mean CLS was 0.10 ± 0.07 mm. No significant differences were identified between the different diagnosis groups in age, sex, best-corrected visual acuity, intraocular pressure, white-to-white, axial length, central corneal thickness, anterior chamber depth, flat keratometry, steep keratometry or iridotomy diameter (p > 0.05). The unattached group had shorter trabecular-ciliary process distance (p = 0.021) and larger ciliary process area (p = 0.001) compared with the attached group. Small CLS and its potential effect (partial ciliary block) might be considered as one of the mechanisms of PACD.