Correlation Between Lens Density Measured by Swept-Source Optical Coherence Tomography and Phacodynamic Parameters of Centurion Phacoemulsification.

PURPOSE: To evaluate the correlation between lens density measured by IOL-Master 700 based on swept-source optical coherence tomography (SS-OCT) technology and the phacodynamic parameters of Centurion phacoemulsification in cataract surgery. METHODS: This prospective study included 66 patients (83 eyes) with age-related cataracts. Using the Lens Opacities Classification System III (LOCS III), the lens nuclear color (NC), lens nuclear opalescence (NO), cortical (C), and posterior subcapsular (P) opacities were obtained. Six meridian orientations of IOL-Master 700 images were captured, and the lens and nuclear regions were analyzed using ImageJ to generate the average lens nucleus density (AND) and average lens density (ALD). Phacodynamic parameters were recorded. The correlation between lens density and the phacodynamic parameters was analyzed. According to the AND, patients were divided into four groups (soft, medium-hard, hard, and extremely hard nucleus), and the phacodynamic parameters were compared among groups. RESULTS: The correlation between the AND obtained by LOCS III grading and SS-OCT-based cataract quantification system score (NC and NO) was statistically significant (rNC = 0.795, rNO=0.794, both p = .000). AND correlated significantly with cumulative dissipated energy (CDE, r = 0.545, p = .000), total ultrasound time (TUST, r = 0.354, p = .001), and total torsional ultrasound time (TTUT, r = 0.314, p = .004). Among the four groups divided by AND, the difference in CDE (P13 = 0.002, P14 < 0.001, P24 = 0.002) was statistically significant. CONCLUSION: AND measured by IOL-Master 700, SS-OCT correlated significantly with LOCS III classification and phacodynamic parameters of the Centurion system, especially with CDE, TUST, and TTUT. AND can be used as an indicator for quantitative evaluation and help inform the surgical plan.

Morphological changes in the iridocorneal angle and their relationship with intraocular pressure after infantile cataract surgery.

AIM: To evaluate morphological changes in the iridocorneal angle after pediatric cataract surgery. METHODS: Children who underwent primary infantile cataract surgery were included and 64 eyes from 41 children, including 18 with unilateral cataracts (18 eyes) and 23 with bilateral cataracts (46 eyes) were examined. All patients underwent two gonioscopic examinations to evaluate the iridocorneal angle, before the primary lens removal and before the secondary intraocular lens implantation. The anatomical changes in the iridocorneal angle and the relationship between intraocular pressure (IOP) and iridocorneal angle changes were also analyzed. RESULTS: The iridocorneal angle was wide in 64 eyes before and after surgery. The trabecular meshwork pigmentation, number of iris processes in every quadrant of the iridocorneal angle, and the width of the ciliary body band in the superior and inferior quadrants at the second gonioscopic examination were significantly increased compared to those at the first examination (P<0.001, P<0.05, P<0.05, and P<0.05, respectively). IOP gradually increased at 1mo after operation, and returned to the preoperative level at 3mo. However, IOP still increased significantly at 6 and 12mo. CONCLUSION: The main changes after pediatric cataract surgery include an increase in trabecular meshwork pigmentation and number of iris processes, IOP gradually increase and has positive correlation with trabecular meshwork pigmentation and anterior insertion of iris process.

Macular Morphologic and Microvascular Analysis in Pseudophakic Children with Previous Pediatric Cataract Using Optical Coherence Tomography Angiography.

INTRODUCTION: The macular morphologic and microvascular changes in children with pseudophakia after pediatric cataract surgery remain unknown. The aim of this study was to analyze macular morphologic and microvascular remodeling in children with pseudophakia after pediatric cataract surgery using optical coherence tomography angiography (OCTA). METHODS: Consecutive cases between December 1, 2018, and November 31, 2020 were recruited. Sixty-one participants (31 pseudophakic children and 30 healthy controls) met the inclusion criteria and were included for final analysis. OCTA was used to measure macular vascular density, the foveal avascular zone (FAZ), and macular thickness. The parameters were compared between pseudophakic and healthy eyes using binary logistic regression, with adjustment for the effect of refractive error, age, and axial length. RESULTS: Compared with normal eyes, a significantly reduced area of the FAZ (p = 0.042), increased superficial foveal vascular density (p = 0.033), and increased inner and outer foveal thickness (p = 0.034 and 0.029, respectively) were noted in pseudophakic eyes. The deep parafoveal vascular density was generally lower in eyes with cataracts (p ≤ 0.044). The inner foveal thickness was positively correlated with the superficial foveal vascular density (r = 0.889, p < 0.001) and negatively correlated with the area of the FAZ (r = -0.903, p < 0.001). The outer foveal thickness was positively correlated with the deep foveal vascular density (r = 0.399, p = 0.002). CONCLUSIONS: Morphological and microvascular remodeling in children with previous pediatric cataract indicates foveal underdevelopment. The underlying mechanism requires further investigation.

Air pollutant emission and reduction potentials from the sintering process of the iron and steel industry in China in 2017.

The iron and steel industry (ISI) is one of the most energy-intensive industries in China, which makes a substantial contribution to the emissions of air pollutants. Among the various manufacturing processes, sintering is the major emitting process, which shares over half of the emissions of sulfur dioxide (SO2), nitrogen oxide (NOx) and particulate matter (PM) for the entire industry. In this study we made a comprehensive evaluation of the air pollutant emissions from the sintering process of China's ISI in 2017 based on the Continuous Emission Monitoring System (CEMS) database and estimated the future reduction potentials. We found that there was a general decreasing trend of emission concentrations in the sintering flue gas in response to the strengthened emission control policies, but the mild increase of the oxygen content in the second half of the year flattened the decreasing trend, indicating the necessity for simultaneous control of the oxygen content in the flue gas. Despite the relative high standard-reaching rates of 90% to the emission concentration limits in GB 28662-2012, the standard-reaching rates to the ultra-low emission standards were only 12%, 40% and 27% for NOx, SO2 and PM respectively, with the lowest value mostly occurred in the western provinces. In 2017, the NOx, SO2 and PM emissions from the sintering process were 378.6 kt, 169.0 kt and 51.9 kt, respectively. If the ultra-low emission standards were met, the corresponding NOx, SO2 and PM emissions would decrease by 69.9%, 52.9%, and 56.4% respectively, illustrating large emission reducing potentials by achieving the ultra-low emission standards.

Clinical outcomes of single-step transepithelial photorefractive keratectomy and off-flap epipolis-laser in situ keratomileusis in moderate to high myopia: 12-month follow-up.

BACKGROUND: To compare the quantitative and qualitative optical outcomes of single-step transepithelial photorefractive keratectomy (TPRK) and off-flap epipolis-laser in situ keratomileusis (Epi-LASIK) in moderate to high myopia. METHODS: In this prospective self-control study, we included patients with moderate to high myopia who were randomized to undergo TPRK in one eye and Epi-LASIK in the other eye. Twelve-month follow-up results for visual acuity, refraction, ocular high-order aberrations, contrast sensitivity, postoperative pain, epithelial healing, and haze grade were assessed. RESULTS: A total of 64 eyes (32 patients) were enrolled in the study. More eyes completed re-epithelialization in the TPRK group than in the Off-flap Epi-LASIK group 3-4 days postoperatively, while all eyes completed re-epithelialization by 7 days. More eyes achieved a visual acuity (both UDVA and CDVA) of better than 20/20 in the TPRK group than in the Off-flap Epi-LASIK group. The ±0.50 D predictability for correction of the spherical equivalent (SE) was higher in the eyes of the TPRK group (91%) than in those of the off-flap Epi-LASIK group (80%) 12 months after surgery. No significant differences in ocular aberrations, including coma, spherical, and trefoil, were found between the two groups at 12 months. There were also no significant differences in visual acuity, contrast sensitivity, pain, and haze grading between the two groups. CONCLUSIONS: Both TPRK and off-flap Epi-LASIK are safe, effective, and predictable treatments for moderate to high myopia with comparable surgical outcomes. TRIAL REGISTRATION: This study was retrospectively registered on ClinicalTrial.gov ( NCT05060094 , 17/09/2021).

Posterior Capsular Outcomes of Pediatric Cataract Surgery With In-The-Bag Intraocular Lens Implantation.

Aim: To investigate the change of posterior capsular outcomes of pediatric cataract surgery with primary in-the-bag intraocular lens (IOL) implantation. Methods: We conducted a case series of pediatric cataract children who underwent cataract extraction with primary in-the-bag IOL implantation, posterior capsulorhexis or vitrectorhexis, and limited anterior vitrectomy at the Eye Hospital of Wenzhou Medical University between 2016 and 2019. Digital retro-illumination photographs of pediatric eyes were obtained at baseline and 6 months, 12 months, and the last visit postoperatively. Capsular outcomes of the posterior capsular opening area (PCOA) and lens reprolifration area at those time points were compared. Correlations between the PCOA and influential factors, such as age at surgery, axial growth, and follow-up duration, were analyzed. The study was registered at register.clinicaltrials.gov (NCT04803097). Results: Data of 23 patients (27 eyes) were used in the final analysis. During follow-up, the PCOA enlarged at a rate of 0.29-0.32 mm2/month during the first six months postoperatively and 0.05-0.08 mm2/month over the next 1-2 years. Six months postoperatively, the PCOA enlargement statistically and positively correlated with the follow-up duration and axial growth. The area of lens reprolifration was 0.46 ± 1.00 mm2 at six months postoperatively and then remained stable. Conclusion: The PCOA enlarged rapidly within the first six months after the pediatric cataract surgery with primary IOL implantation. Six months postoperatively, the enlargement of PCOA was positively correlated with follow-up duration and axial growth. Posterior capsulorhexis or capsulectomy should be performed with a diameter of 3.0 to 4.0 mm for good visual axis transparency and the protection of in-the-bag IOL.

Glaucoma and risk factors three years after congenital cataract surgery.

BACKGROUND: This study aimed to identify the incidence of and risk factors for postoperative glaucoma-related adverse events at various time points after congenital cataract surgery. METHODS: This retrospective cohort study enrolled 259 eyes from 174 patients (surgical age ≤ 7 years) who underwent congenital cataract surgery. All surgical procedures were conducted at the Eye Hospital of Wenzhou Medical University between May 2011 and March 2019. Patients were classified into group 1 [primary intraocular lens (IOL) implantation, N = 111 eyes], group 2 (secondary IOL implantation, N = 85 eyes), and group 3 (no IOL implantation, N = 63 eyes). We recorded demographic factors and incidence and risk factors for glaucoma-related adverse events. RESULTS: Glaucoma-related adverse events occurred in 21 (8.1%) eyes, whereas 27 (10.4%) eyes developed steroid-induced ocular hypertension. The percentage of glaucoma-related adverse events was 0%, 1.2%, 1.2%, 1.6%, 4.0%, and 8.9% at 1 month, 6 months, 1 year, 2 years, 3 years and 4 years after surgery, respectively. Sixteen (18.8%), five (7.9%), and zero eyes developed glaucoma-related adverse events in groups 2, 3, and 1, respectively. Family history of congenital cataract [hazard ratio (HR), 50.463; 95% confidence interval (CI), 7.051-361.139; P < 0.001], preoperative central corneal thickness (CCT) [HR, 1.021; 95% CI, 1.009-1.034; P = 0.001], preoperative horizontal corneal diameter (HCD) [HR, 3.922; 95% CI, 1.558-9.804; P = 0.004], and preoperative lens thickness (LT) [HR, 3.745; 95% CI, 1.344-10.417; P = 0.012] were identified as predictors of postoperative glaucoma-related adverse events. CONCLUSIONS: Family history of congenital cataract, thicker preoperative CCT, smaller preoperative HCD, and thinner preoperative LT are the main risk factors of postoperative glaucoma-related adverse events. Regular monitoring of children after cataract surgery with these risk factors may help ophthalmologists detect susceptible individuals and provide timely interventions in the clinic.

A GEE model for predicting axial length after cataract surgery in children younger than 2 years of age.

PURPOSE: To develop a model for predicting postoperative axial length (AL) in children undergoing cataract surgery younger than 2 years of age. SETTING: The Eye Hospital of Wenzhou Medical University, Hangzhou, China DESIGN: Retrospective study. METHODS: Children were included only if AL data were available before surgery and at least 1 year after surgery. Eyes were divided into pseudophakic, aphakic, and unaffected eye groups. Variables that could influence axial growth were analyzed and a multivariable generalized estimating equation regression model was developed to predict postoperative AL. RESULTS: 333 eyes from 190 patients were included. We observed a logarithmic linear correlation between age and AL in the unaffected eye group, AL = (2.7924 × log of age in months) + 17.607, R2 = 0.6596. Meanwhile, The GEE model of eyes with cataracts can be written as follows: Postoperative AL = 6.408 + 0.611 × (baseline AL) + 0.007 × (baseline age) - -0.006 (baseline age) × (age at follow-up) - -0.391 × coefficient of surgery. The ages were recorded in months, the ALs were recorded in millimeter. CONCLUSIONS: The assessment of AL is one of the most important parts of successful postoperative management in congenital cataract patients. This study established an AL estimate formula for children aged ≤ 2 years with congenital cataract who underwent cataract surgery. This model theoretically could be used to predict individual future AL for child undergoing cataract surgery.

Effect of age and cycloplegia on the morphology of the human crystalline lens: swept-source OCT study.

PURPOSE: To evaluate the effect of age and cycloplegia on the morphology of the crystalline lens using a swept-source optical coherence tomography (SS-OCT) system. SETTING: Hospital. DESIGN: Prospective cross-sectional study. METHODS: The parameters including anterior chamber depth (ACD), the radii of curvature of the anterior and posterior surface of the crystalline lens (ALR and PLR), lens thickness (LT), lens equatorial diameter (LED), and lens vault (LV) were quantified by the SS-OCT before and after cycloplegia. The paired t test was used to compare the parameters before and after cycloplegia. A multivariate linear regression model was built to analyze the association between the parameters/cycloplegia-induced changes and age, while adjusting for the effect of axial length, refractive status, and sex. RESULTS: 76 individuals (age range, 18 to 86 years) were recruited. The ALR and ACD were negatively correlated with age (P ≤ .002), and the LT, LV, and LED were positively correlated with age (P ≤ .004). In participants younger than 60 years, the ALR and ACD significantly increased, whereas the LV and LT significantly decreased after cycloplegia (all P < .001). With aging, cycloplegia-induced differences of ALR (P = .001) and ACD (P = .014) significantly decreased, and of LT (P < .001), LT (P < .001), and LV (P = .001) significantly increased. CONCLUSIONS: The crystalline lens morphology measured by the SS-OCT revealed steepening anterior surface and increasing equatorial diameter with age. Cycloplegia caused a significant change of anterior surface morphology in participants younger than 60 years, and this effect diminished with age.

Meibomian Gland Morphology Changes After Cataract Surgery: A Contra-Lateral Eye Study.

Purpose: To evaluate the morphology changes of meibomian glands (MGs) after cataract surgery. Setting: Hangzhou Branch of the Eye Hospital of Wenzhou Medical University, Zhejiang, China. Methods: In this contra-lateral eye study, 40 patients received unilateral cataract surgery for age-related cataract. All the patients underwent the evaluation of non-invasive break-up time (NIBUT) and lower tear meniscus height (TMH) before the surgery and 6 months post-operatively. The MGs were evaluated via ImageJ and Meibomian Gland Bio-image Analyzer. MG dropout, length, width, area, gland diameter deformation index (DI), and gland signal index (SI) were recorded. Results: MG length, width, area, DI, and SI were significantly decreased after cataract surgery in the study group (operated eyes, P < 0.001, P = 0.003, P < 0.001, P = 0.001, and P < 0.001, respectively) and showed no significant changes in the control group (non-operated eyes) (all P > 0.05). MG loss increased more in the study group (P = 0.030), and the changes in TMH and NIBUT were not significantly different between the two eyes (both P > 0.05). Conclusion: Cataract surgery aggravated meibomian gland morphology, such as MG loss, MG length, width, area, and SI, and produced no change in NIBUT and TMH at 6 months post-operatively.

Assessment of anterior chamber angle changes after phacoemulsification with swept-source OCT.

AIM: To assess the changes of anterior chamber angle in patients with shallow anterior chamber after phacoemulsification combined with intraocular lens (IOL) implantation, based on anterior segment swept-source optical coherence tomography (AS-SS-OCT) measurements. METHODS: This was a prospective case control study; sixty eyes of sixty case were scheduled for cataract surgery with normal intraocular pressure (IOP). Based on anterior chamber depth (ACD) and gonioscopy findings, the eyes were divided into two groups: group of shallow anterior chamber and narrow angle (SAC group, 30 eyes); and group of normal anterior chamber group with wide angle (NAC group, 30 eyes). Measurements of ACD, anterior chamber volume (ACV), iris volume (IV), lens vault (LV), angle opening distance (AOD), angle recess area (ARA), trabecular iris space area (TISA), and trabecular iris angle (TIA) were conducted in each group before and 3mo after surgery. RESULTS: There was no significant difference in age, axial length (AL), corneal curvature, corneal diameter, intraocular pressure, and IV between two groups before surgery, except for the LV (P=0.000). ACD and ACV were prominently larger in the NAC group than the SAC group 3mo after operation (3.69±0.38 vs 3.85±0.39 mm, P=0.025; 161.37±19.47 vs 178.26±20.30 mm3, P=0.002). AOD750, ARA750 in nasal and inferior quadrants, TISA750 in all quadrants except temporal, and TIA750 in all quadrants in SAC group were significantly smaller than those in NAC group after operation (all P<0.05). CONCLUSION: Cataract surgery can deepen anterior chamber and increase the width of anterior chamber angle in Chinese subjects, but the angle related parameters including AOD750, ARA750, TISA750, TIA, TISA750, and ACV in patients with shallow anterior chamber and narrow angle do not reach the normal level.

Age-related changes in crystalline lens tilt and decentration: swept-source OCT study.

PURPOSE: To investigate the age-related tilt and decentration of crystalline lenses using a swept-source optical coherence tomography biometer (SS-OCT) (CASIA2, Tomey Corp.). SETTING: Eye Hospital, Wenzhou Medical University, Wenzhou, Zhejiang, China. DESIGN: Cross-sectional study. METHODS: The direction and magnitude of the crystalline lens were evaluated in 230 participants with ages ranging from 7 to 90 years using SS-OCT. The participants were divided into 4 age groups, and the differences among the groups were analyzed. Multiple linear regression was used to investigate the main factors influencing crystalline lens tilt and decentration. RESULTS: The natural crystalline lens tilted toward the inferotemporal direction with a mean magnitude of 4.3 ± 1.5 degrees (range 0.7 to 8.95 degrees). The mean decentration toward the superotemporal direction was 0.17 ± 0.12 mm (range 0.03 to 1.15 mm). There was mirror symmetry between the right and left eyes. There were statistically significant differences in the crystalline lens tilt and decentration among the age groups. Multiple linear regression showed that changes in crystalline lens tilt depended on angle α (P < .01) and anterior chamber depth (ACD; P = .008), whereas crystalline lens decentration depended on angle κ (P = .003), age (P < .01), and angle α (P = .002). CONCLUSIONS: Although there was a statistically significant difference in crystalline lens tilt and decentration among age groups, the variation in the crystalline lens position was partially affected by age. The crystalline lens tilt was greater in eyes with wider angle α and shallower ACD, whereas crystalline lens decentration was greater in younger eyes with wider angles κ and α.

Early changes in retinal microcirculation after uncomplicated cataract surgery using an active-fluidics system.

PURPOSE: To evaluate the early changes in retinal microcirculation after uncomplicated cataract surgery using an active-fluidics system. MATERIALS AND METHODS: Patients underwent uncomplicated cataract surgery for both eyes were enrolled. The two eyes of the patients were randomly assigned to two groups, the active-fluidics group and the gravity-fluidics group. One eye using an active-fluidics system, and the other using a gravity-fluidics system. Optical coherence tomography angiography (OCTA) was performed at 1 day, 7 days, 30 days, and 90 days after surgery. RESULTS: Fifty eyes (25 patients) were included in the final analysis. A significantly lower cumulative dissipated energy (CDE), estimated fluid usage (EFU), and total aspiration time (TAT) were observed in the active-fluidics group (all P<0.05). The superficial vessel density at parafoveal region increased at 7 days and 30 days after cataract surgery in the eyes of both the active-fluidics and gravity-fluidics groups, with the fluctuation in eyes of the gravity-fluidics group more significant. The vessel density of deep capillary plexus remained stable during the follow-up period. Significant changes of retinal thickness in macular region (fovea, parafovea) were observed in eyes of the gravity-fluidics group through the comparison of corresponding values at different time points (p = 0.008, 0.005). No significant change in retinal thickness was observed in eyes of the active-fluidics. CONCLUSIONS: Retinal microcirculation and thickness were disturbed after cataract surgery using the gravity-fluidics infusion system. The active-fluidics system not only improved the surgical efficacy but also protected the retinal vasculature during cataract surgery. CLINICAL TRIALS REGISTRATION: The study has been registered at www.clinicaltrials.gov with its clinical trial accession number of NCT0130500.

Agreement between anterior segment parameters obtained by a new ultrasound biomicroscopy and a swept-source fourier-domain anterior segment optical coherence tomography.

Purpose: To evaluate the agreement between anew UBM and an SS-OCT. Methods: The scans of the right eye of each volunteer were obtained using the two devices. Data were fitted and recorded including: central corneal thickness (CCT), aqueous depth (AQD) (the distance from endothelium to lens), angle-to-angle distance (ATA), lens thickness (LT), diameter of the lens in the horizontal direction (LDiaangle: distance between the sharp angles on both sides of the lens, LDiaarc: distance between the vertex of the circular arcs on both sides of the lens), anterior and posterior corneal radius (Rf and Rb). Results: 25 eyes were included in this study. It could be seen that the differences in CCT, LDiaangle, Rf measured by the two instruments were not statistically significant. Bland-Altman analysis plots of CCT, LDiaangle and Rf showed mean differences of 0.2 µm, 0.01mm and 0.0mm for the 2 devices, respectively. Conclusion: The values of CCT, LDiaangle and Rf obtained via two instruments were not clinically interchangeable and the AQD, ATA, LT, and Rb have poor agreement affected by accommodation. We can estimate the real lens diameter by subtracting 0.61 ± 0.43mm when the lens diameter can only be simulated with SS-OCT.

Expression Profiles of Inflammatory Cytokines in the Aqueous Humor of Children after Congenital Cataract Extraction.

Purpose: To investigate the change in cytokine microenvironment of the aqueous humor (AH) after surgery in children with congenital or developmental cataracts. Methods: AH samples were obtained from 59 eyes diagnosed with a congenital or developmental cataract. Thirty-three of these eyes were aphakic following previous cataract surgery and were scheduled for secondary intraocular lens (IOL) implantation. Additionally, AH samples from 26 eyes that had not undergone surgery were taken. AH samples were then analyzed for 16 different inflammatory immune mediators using multiplex bead immunoassays and enzyme-linked immunosorbent assay (ELISA). Results: The mean interval between secondary IOL implantation and original cataract surgery was 24.85 months (range, 9-60 months). Levels of IL-6, IP-10 (CXCL10), MCP-1 (CCL2), and IL-2 were significantly elevated in the AH of eyes after surgery compared to eyes that did not undergo surgery (P < 0.001, P = 0.047, P = 0.006, P = 0.012, respectively). There was significant correlation between the levels of TGF-ß2 and intraocular pressure (IOP) in postsurgical and nonsurgical eyes (r = 0.532, P = 0.006; r = 0.57, P = 0.001). Postsurgical outcomes, such as iris adhesions, capsular fibrosis, and capsular contraction, were found not to be significantly associated with cytokine levels in the AH after surgery; however, IL-6 levels in capsular exposure eyes were significantly higher than those in cortical closure eyes (P = 0.023). Conclusions: To our knowledge, this is the first study to report significantly increased proinflammatory cytokine levels in the AH after congenital cataract extraction in children. Our study also suggests that this proinflammatory state may be maintained for a prolonged period of time. Overall, these results give us insight into the relationship between the inflammatory cytokine microenvironment of the aqueous humor and potential long-term complications following congenital cataract surgery. Translational Relevance: The inflammatory cytokine microenvironment of the aqueous humor might help explain potential long-term complications after surgery in patients with congenital or developmental cataracts.

Comparison of the Accuracy of IOL Power Calculation Formulas for Pediatric Eyes in Children of Different Ages.

PURPOSE: This study aims to compare the accuracy of five intraocular lens (IOL) power calculation formulas (SRK/T, Hoffer Q, Holladay 1, Haigis, and Holladay 2) for pediatric eyes in children of different ages. METHODS: In this prospective study, patients who received cataract surgery and IOL implantation in the capsular bag were enrolled. We compared the calculation accuracy of 5 formulas at 1 month postoperatively and performed subgroup analysis with the patients divided into three groups according to their ages at the time of surgery as follows: group 1 (age ≤ 2 years, 35 eyes), group 2 (2 years < age < 5 years, 38 eyes), and group 3 (age > 5 years, 29 eyes). RESULTS: 75 patients (102 eyes) were enrolled in this study. The Haigis formula got the smallest PE among all formulas in all three groups. With regard to APE, there were no statistical differences among the formulas except group 2, with the SRK/T formula a little smaller, the Holladay 2 formula a little larger in group 1, and the Haigis formula a little smaller in group 3. In group 2, the Haigis formula had the lowest APE (0.87 ± 0.61 D), while the Holladay 2 formula had the largest (1.71 ± 1.20 D, p < 0.001), followed by the Holladay 1 formula (1.51 ± 1.07 D, p=0.002). On comparing the percentage of APE within 0.5 D and 1.0 D obtained with 5 formulas in each group, there were no statistical differences. The SRK/T formula and the Holladay 1 formula showed the highest percentage (40.00% and 60.00%) in group 1. While the Haigis formula got the highest percentage in less than 0.5 D (34.21%) and less than 1 D (60.53%) in group 2. In group 3, the Holladay 2 formula and the Haigis formula got the highest percentage less than 0.5 D (58.62%) and less than 1 D (79.31%). The multiple linear regression indicated that the age at the time of surgery was a significant factor affecting the accuracy of APE; after removing the age, AL was the only factor that affected the accuracy of APE. CONCLUSION: The SRK/T and the Holladay 1 formulas were relatively accurate in patients younger than 2 years old, while the Haigis formula performed better in patients older than 2.

Keratolenticular adhesion removal for type 2 Peters anomaly: a case report.

BACKGROUND: Type 2 Peters anomaly is a rare anterior segment disorder characterized by central corneal leukoma with keratolenticular adhesion and cataract. Performing cataract surgery without corneal tissue transplantation in patients of type 2 Peters anomaly is extremely rare and challenging. We present a case of type 2 Peters anomaly treated by peeling off the adhesion without penetrating keratoplasty (PKP), in which restoration of corneal transparency is observed. CASE PRESENTATION: An 11-month-old female infant of type 2 Peters anomaly presented with bilateral corneal opacity with distinct demarcation, keratolenticular adhesion and cataract, which was first noted at the age of 3 months. By peeling off the adhesion from corneal endothelium combined with lensectomy and vitrectomy, there was a gradual reduction in corneal opacity and improvement in visual acuity after surgery over a 2-year period. Her visual acuity had improved from light perception preoperatively to 20/50 at the latest follow-up. No sight-threatening postoperative complications were noted. CONCLUSION: It is safe and effective to peel off the keratolenticular adhesion in patients of type 2 Peters anomaly presented with distinctly demarcated corneal opacity.

Longitudinal changes of the macular structure after lens removal combined with anterior vitrectomy after pediatric cataract surgery.

PURPOSE: To explore the macular thickness changes after lens removal combined with anterior vitrectomy for pediatric cataract surgery. SETTING: The Eye Hospital of Wenzhou Medical University, Zhejiang, China. DESIGN: Prospective study. METHODS: Thirty children (40 eyes) aged between 3 years and 9 years with pediatric cataracts, including 20 children (20 eyes) with unilateral cataracts and 10 children (20 eyes) with bilateral cataracts, were enrolled. Spectral-domain optical coherence tomography was used to obtain macular images. Central subfield thickness (CST) and retinal thickness in the Early Treatment Diabetic Retinopathy Study subfields (inner 1.0 to 3.0 mm annulus and outer 3.0 to 6.0 mm annulus) were recorded preoperatively as well as at 1, 3, 6, and 12 months postoperatively. RESULTS: Forty eyes of 30 children were included. Retinal thickness in every subfield significantly thickened at 3 months postoperatively (all P < .05). CST significantly thickened compared with preoperative levels (228.03 ± 18.58 vs 240.35 ± 17.41, P = .005) at 3 months postoperatively; macular thickness gradually decreased in the following months. At 6 months postoperatively, retinal thickness in inner nasal, inferior, temporal, and outer nasal subfields remained significantly thicker compared with preoperative levels (P = .048, P = .036, P = .029, and P = .017, respectively). At 12 months, the retinal thickness in all subfields reached the preoperative level. CONCLUSIONS: The influence on macular thickness lasted until 12 months after pediatric cataract surgery. The inner macular thickness increased for a longer time than the outer macular thickness postoperatively.

Clinical Characteristics and Surgical Safety in Congenital Cataract Eyes with Three Pathological Types of Posterior Capsule Abnormalities.

PURPOSE: To observe the clinical characteristics of 3 pathological types of posterior capsule abnormalities (PCAs) in congenital cataracts (CCs) and evaluate the surgical safety in these eyes. METHODS: This study involved 239 children (367 eyes) with CC who underwent cataract surgery at the Eye Hospital of Wenzhou Medical University. All surgery videos were collected for detailed reviews. Intraoperative and postoperative complications (within 3 months) were all recorded. RESULTS: The 3 pathological types of PCAs, namely, persistent fetal vasculature (PFV), posterior capsule defect (PCD), and posterior lenticonus (PLC), presented in 129 (35.1%) CC eyes, while 238 (64.9%) eyes were recorded as CC without PCA. The percentages of PFV, PCD, and PLC were 10.9%, 26.7%, and 5.4% in CC eyes (n = 367), respectively. The most common concomitant of PFV eyes was PCD (42.5%), and PFV was the most frequent (17.3%) one in PCD eyes. PLC was only associated with PFV (15%) and PCD (50%). The occurrence rates of surgical complications ranged from 0 to 5.4%, and no statistical difference was found between the eyes with and without PCA (all P > 0.05). CONCLUSIONS: PFV, PCD, and PLC play a very important role in the CCs. The effect of fetal vessels in PFV eyes might be an abnormally strong attachment on the posterior capsule, leading to PLC and PCD. Even in PCA patients, severe surgical complication can also be avoided with well-designed and skilled operation. This trial is registered with NCT03905044 at http://ClinicalTrials.gov.

Accuracy of 8 intraocular lens power calculation formulas in pediatric cataract patients.

PURPOSE: To compare the accuracy of the eight formulas for intraocular lens (IOL) power calculation in pediatric cataract patients. METHODS: A retrospective study. A total of 68 eyes (68 patients) that underwent uneventful cataract surgery and posterior chamber IOL implantation in the capsular bag were enrolled. We compared the calculation accuracy of the 8 formulas at 1 month postoperatively and performed subgroup analysis according to age or axial length (AL). RESULTS: The mean age at surgery was 34.07 ± 24.60 months and mean AL was 21.12 ± 1.42 mm. The mean prediction errors (PE) of eight formulas for all patients were as follows: SRK II (- 0.66), SRK/T (- 0.44), Holladay 1 (- 0.36), Hoffer Q (- 0.09), Olsen (0.71), Barrett (0.37), Holladay 2 (- 0.70), and Haigis (0.50). There was significant difference among the 8 formulas (p < 0.0001), while no significant difference of absolute PE was found among the 8 formulas in all patients (p = 0.053). Moreover, in patients younger than 2 years old or with AL ≤ 21 mm, SRK/T formula was relatively accurate in 34% and 39% of eyes, respectively. While in patients older than 2 or with AL > 21 mm, Barrett and Haigis formulas were better (58% and 47% for Barrett, 52% and 53% for Haigis). CONCLUSION: Overall, in patients younger than 2 years old or with AL ≤ 21 mm, SRK/T formulas were relatively accurate, while Barrett and Haigis formulas were better in patients older than 2 or with AL > 21 mm.