Changes in corneal endothelial cells after scleral-fixated intraocular lens surgery in children with congenital ectopia lentis: 2-year follow-up.

PURPOSE: To investigate the changing patterns of corneal endothelial cells and the associated factors in children with congenital ectopia lentis (CEL) after scleral-fixated intraocular lens (SF IOL) surgery. SETTING: Zhongshan Ophthalmic Center, Guangzhou, China. DESIGN: Retrospective study. METHODS: Patients were divided into the surgery group and the control group. Central endothelial cell density (ECD), coefficient of variation in cell size, the percentage of hexagonal cells (hexagonality), average cell size (AVG), and central corneal thickness were analyzed for both groups at baseline and each follow-up visit. Clinic characteristic, ocular parameters, IOL decentration, and IOL tilt of patients in the surgery group were collected. Multiple linear regression was performed to assess the potential associated factors for the postoperative changes in corneal endothelial cells in the surgery group. RESULTS: After 2-year follow-up, the decline of ECD was 17.8% (95% CI, -21.8 to -13.9) in the surgery group and -3.1% (95% CI, -5.2 to -1.0) in the control group ( P < .001), while the increase of AVG was 24.3% (17.1-31.6) in the surgery group and 2.7% (1.0 to 4.5) in the control group ( P < .001). Multivariate analysis showed that axial length (AL) ≥24 mm and white-to-white (WTW) <12.2 mm were significantly associated with greater loss of ECD (ß = -241.41, 95% CI, -457.91 to -24.91, P = .030 and ß = 251.63, 95% CI, 42.10-461.17, P = .020, respectively) and AL ≥24 mm was significantly positively associated with the increase of AVG (ß = 34.81, 95% CI, 0.90-68.71, P = .044). CONCLUSIONS: The SF IOL had a significant impact on corneal endothelium in children with CEL. More attention should be paid to monitor postoperative corneal endothelium change during long-term follow-up in CEL children, especially for those with longer AL and smaller WTW.

Longitudinal changes of refractive error in preschool children with congenital ectopia lentis.

BACKGROUND: Congenital ectopia lentis (CEL) is a hereditary eye disease which severely impacts preschool children's visual function and development. This study aimed to evaluate the longitudinal changes in spherical equivalent (SE) refractive error in preschool children with CEL. METHODS: A retrospective cohort study was conducted at Zhongshan Ophthalmic Center, Guangzhou, China. Medical records of CEL patients under 6-year-old who were diagnosed with Marfan syndrome at the initial visit from January 2014 to March 2022 were collected and were divided into surgery and non-surgery groups. Mean change rate of SE in the two groups was evaluated, and the potential associated factors of SE change rate were investigated by mixed-effect regression model. RESULTS: A total of 94 preschool patients from 14 provinces of China were included. Among the 42 children of the surgery group, the mean age with standard deviation (SD) was 5.02 ± 0.81 years and patients experienced a myopic shift of -0.05 ± 0.09 D/month in average. The mean age with SD of the 52 children of the non-surgery group was 4.34 ± 1.02 years, and the mean myopic shift was -0.09 ± 0.14 D/month. The mixed-effect regression model identified that higher degree of myopia at baseline was associated with slower myopic shift both in surgery (ß = 0.901, 95% CI: 0.822 ~ 0.980, P < 0.001) and in non-surgery group (ß = 1.006, 95% CI: 0.977 ~ 1.034, P < 0.001) in CEL patients. Surgical treatment (ß = 2.635, 95% CI: 1.376 ~ 3.894, P < 0.001) was associated with slower myopic shift in all participants CEL patients. CONCLUSIONS: Myopic progression was slower in the surgery group than in the non-surgery group of CEL. Preschool CEL patients who met the surgical indication are suggested being performed with timely surgery to slow down the myopic progression.

Postoperative longitudinal refractive changes in children younger than 8 years with ectopia lentis and Marfan syndrome.

PURPOSE: To evaluate the postoperative longitudinal refractive changes in children younger than 8 years with ectopia lentis and Marfan syndrome (MFS). SETTING: Zhongshan ophthalmic center, Guangzhou, China. DESIGN: Retrospective cohort study. METHODS: Medical data of patients diagnosed with ectopia lentis and MFS that underwent surgery younger than 8 years were collected. Refractive errors and ocular biometric parameters were collected preoperatively and at each follow-up visit. Patients were stratified into groups according to age at surgery, and only the eye operated on first was selected. Multivariate analysis was performed to determine the association between refractive shift and potential risk factors. RESULTS: In total, 54 eyes of 54 patients were enrolled. The median age at surgery was 6.21 years (interquartile range [IQR], 5.25 to 6.85), and the median follow-up was 2.0 years (IQR, 1.2 to 2.8 years). At age 8 years, patients demonstrated a median myopic shift ranged from -1.75 diopters (D) (IQR, -2.75 to -1.00 D) for the 4-year-old group to -0.13 D (IQR, -0.50 to -0.06 D) for the 7-year-old group. Multivariate analysis showed that greater myopic shift was associated with younger age at surgery ( P = .004), male sex ( P = .026), and shorter preoperative axis length ( P = .005). CONCLUSIONS: A tendency toward increasing postoperative myopic was demonstrated in children with ectopia lentis and MFS, with the greatest myopic shift in the younger age groups. If the goal is to reach emmetropia by age 8 years, the immediate postoperative hypermetropic targets should be 1.75 D for age 4 years, 1 D for age 5 years, 0.5 D for age 6 years, and 0 to 0.25 D for age 7 years.

Biomechanical testing of a modified knotless transscleral suture fixation technique: an ex vivo study.

Background: To investigate the safety and effectiveness of a modified transscleral suture through ex vivo tests. Methods: Ex vivo tests were performed in full-thickness porcine scleral pieces using modified knotless transscleral zigzag-shaped suture (Z-suture) fixation technology. The minimum traction force required to loosen or rupture the suture was assessed. The effects of different polypropylene sutures (10-0, 8-0), different suture spans (2.0, 3.0, 4.0 mm), different passes (3, 4, 5 passes), and scleral grooves were investigated. Results: The average minimum traction forces required to loosen 10-0 polypropylene sutured for 3.0 mm with a suture span of 3, 4, and 5 passes, were 0.18 (0.15-0.18), 0.22 (0.21-0.22), and 0.37 (0.37-0.37) N, respectively. The maximum traction force to prevent the suture from rupturing for the 10-0 polypropylene suture was 0.37-0.41 N in the sclera. The average of the minimum traction forces required to loosen the 8-0 polypropylene sutured with 5 passes and spanning 2.0, 3.0, and 4.0 mm were 0.37 (0.3 -0.39), 0.42 (0.42-0.45), and 0.50 (0.50-0.51) N, respectively, which were 14-28% higher than that of the 10-0 polypropylene suture under same conditions (all P values <0.01). In addition, there was no statistical difference (P=0.3258) for the 8-0 polypropylene suture used with a 3.0-mm suture span and 5 passes between conditions with or without scleral grooves. Conclusions: The minimum traction force required to loosen or rupture the suture in the sclera was associated with suture specification, suture span, and the number of passes, but was uncorrelated with double scleral grooves. The 8-0 polypropylene suture with double scleral grooves may be a more favorable choice for knotless transscleral fixation.

A Modified Knotless Transscleral Intraocular Lens Fixation Technology for Congenital Ectopia Lentis.

INTRODUCTION: This study aimed to compare modified knotless transscleral suture fixation of intraocular lens (IOL) with traditional transscleral suture fixation for adolescents and young patients with congenital ectopia lentis (CEL). METHODS: This retrospective cohort study included 49 patients with CEL (60 eyes) who underwent surgery at the Zhongshan Ophthalmic Center. Improvements based on knotless Z-suture fixation technique were made to form a modified knotless method, in which thicker 8-0 polypropylene sutures were used, and double parallel scleral grooves were constructed behind the limbus instead of triangular lamellar scleral flaps to cover suture stitches. Modified knotless transscleral fixation of IOL was conducted on 30 eyes, and the other 30 eyes underwent traditional transscleral fixation surgery. Pre- and postoperative best-corrected visual acuity (BCVA), refractive error, astigmatism, other ocular parameters, and complications were statistically analyzed. RESULTS: For patients in the modified knotless group, the mean cylindrical refractive error and astigmatism at 1 month and 3 months postoperative were lower (all P < 0.05), and the mean IOL tilt degree was smaller at 3 months postoperative (3.21° ± 2.13° vs. 5.65° ± 3.66°, P = 0.032). The incidence of suture exposure in the modified knotless group was also lower than in the controls (0 vs. 16.7%, P = 0.026). No group differences were observed in mean BCVA, spherical equivalent, or other ocular biometric parameters between groups. CONCLUSION: Modified knotless technique was a valid method to achieve optimal IOL position and reduce postoperative astigmatism for adolescents and young patients with CEL. It effectively reduced the incidence of knot-related complications, greatly improved the postoperative comfort, and achieved aesthetic benefits.

Longitudinal Changes of Axial Length and Associated Factors in Congenital Ectopia Lentis Patients.

Purpose: To investigate the longitudinal changes and associated factors of axial length (AL) in congenital ectopia lentis (CEL) patients. Methods: In this retrospective study, medical records of CEL patients were reviewed from January 2014 to December 2019 at the Zhongshan Ophthalmic (ZOC) in China. Patients were divided into the surgery group and the nonsurgery group. Data of refractive power, best-corrected visual acuity (BCVA), and intraocular pressure (IOP) as well as ocular biometrics including AL, corneal curvature, white-to-white (WTW), and central corneal thickness (CCT) were collected at baseline and each follow-up visit. Multiple linear regression was performed to assess the potential associated factors for axial length growth in congenital ectopia lentis patients. Results: Compared with the nonsurgery group, the change rate of AL among children aged 3 to 6 years old was slower in the surgery group (0.443 ± 0.340 mm/year vs. 0.278 ± 0.227 mm/year, P < 0.05). However, no statistically significant difference for the change rate of AL was detected between the surgery group and the nonsurgery group (P > 0.05) among patients aged 7 years or older. For the surgery group, the results of the linear regression model showed that a higher change rate of AL was associated with younger age (older age: ß = -0.009, 95% CI: -0.014 to -0.003, and P=0.002) and worse baseline BCVA (logMAR) (ß = 0.256, 95% CI: 0.072 to 0.439, and P=0.007). As for the nonsurgery group, younger baseline age (older age: ß = -0.027, 95% CI: -0.048 to -0.007, and P=0.01) and longer baseline AL (ß = 0.073, 95% CI: 0.023 to 0.122, and P=0.006) were associated with a higher change rate of AL. Conclusions: The AL change rate was clearly associated with age both in the surgery group and in the nonsurgery group. Intervention strategies such as surgery should be performed earlier for CEL that meets the surgical criteria. Worse baseline BCVA and longer baseline AL are associated factors that would affect the growth rate of AL in the surgery and nonsurgery group, respectively.

Evaluation of Intraocular Lens Tilt and Decentration in Congenital Ectopia Lentis by the Pentacam Scheimpflug System.

Purpose: The purpose of this study was to quantify the characteristics of the tilt and decentration of the IOL after trans-scleral suture fixation surgery in congenital ectopia lentis (CEL) patients. Methods: The clinical characteristics of 70 CEL patients at Zhongshan Ophthalmic Center in China were retrospectively analyzed. The tilt and decentration of intraocular lens (IOL) were measured by using a Pentacam and compared between different axial length (AL) subgroups. The correlation between IOL tilt, decentration, and ocular characteristics was investigated using Spearman's correlation analysis. Results: The postoperative IOL position of CEL patients was mainly located nasally inferiorly. The average tilt of the IOL in CEL patients was less than 7° (for temporal: 2.21 ± 1.53°, for nasal: -1.84 ± 2.04°, for superior: 2.22 ± 2.18°, and for inferior: -1.70 ± 1.62°), and the average decentration of the IOL in CEL patients was larger than 0.4 mm (for temporal: 0.49 ± 0.38 mm, for nasal: -0.69 ± 0.46 mm, for superior: 0.72 ± 0.58 mm, and for inferior: -0.68 ± 0.54 mm). The decentration of CEL patients in the AL ≥ 26 subgroup was greater than those with AL < 24 mm and AL 24 to 26 mm subgroups (for superior: 0.72 ± 0.28 mm vs. 0.46 ± 0.25 mm and 0.48 ± 0.22 mm, all P < 0.05; for inferior: -0.94 ± 0.56 mm vs. -0.44 ± 0.26 mm and -0.44 ± 0.46 mm, all P < 0.05). IOL decentration was positively correlated with AL (for superior: r = 0.44, P=0.019; for inferior: r = 0.54, P=0.006). IOL tilt was positively correlated with AL on the superior side (r = 0.38, P=0.041). Conclusions: The extent of IOL decentration after trans-scleral suture fixation was great in CEL patients, and the IOL decentration in CEL patients was significantly associated with AL.

Accuracy of intraocular lens power formulas for eyes with scleral-sutured intraocular lenses in congenital ectopia lentis.

PURPOSE: To compare the accuracy of intraocular lens (IOL) power calculation formulas in eyes with congenital ectopia lentis (CEL) that underwent scleral-fixated IOL implantation. SETTING: Zhongshan Ophthalmic Center, Guangzhou, China. DESIGN: Retrospective consecutive case-series study. METHODS: 158 eyes from 158 patients diagnosed from December 12, 2017, to November 16, 2020, with CEL and undergoing a lensectomy and scleral fixation of a Rayner 920H or 970C model IOL were retrospectively reviewed. The prediction errors (PEs) of the spherical equivalent of 8 formulas, Barrett Universal II (BUII), Emmetropia Verifying Optical (EVO), Haigis, Hoffer Q, Holladay 1, Kane, Hill-RBF 3.0, and SRK/T, were compared. RESULTS: For CEL patients with scleral-sutured IOL, all 8 formulas yielded myopic PEs without constant optimization. After such optimization, the performance of each formula ranked by median absolute error (MedAE) from the lowest to highest in diopter (D) was as follows: SRK/T (0.47), EVO (0.48), Kane (0.52), BUII (0.53), Hoffer Q (0.58), Holladay 1 (0.59), Haigis (0.61), and Hill-RBF 3.0 (0.62) formulas. The EVO and SRK/T formulas had the highest prediction accuracy concerning the percentage of cases within ±0.50 D and ±1.00 D range of PE in eyes that experienced scleral-sutured IOL surgery, respectively. CONCLUSIONS: All formulas before constant optimization produced myopic PEs. After optimization, the SRK/T and EVO formulas had the lowest MedAE and the highest percentage of PE in the range within ±0.50 D for CEL patients with scleral-sutured IOL implantations.

Endoscopy-guided in vivo evaluation of ciliary sulcus location in children with ectopia lentis.

OBJECTIVE: To assess a new method to measure the distance of the needle passage from the ciliary sulcus to the corneal limbus anterior border (CTC) in eyes with ectopia lentis directly in vivo via endoscopy and to further evaluate the correlations among the CTC, age, automated horizontal white-to-white distance (WTW), and ocular axial length (AL). METHODS: The WTW and AL were measured using an optical biometer. An intraocular endoscope was used during transscleral suture fixation of posterior chamber intraocular lenses to identify the true location of the ciliary sulcus. Linear regression analysis was used to assess the correlation between the CTC and other ocular biological parameters, including age, WTW, and AL. RESULTS: Thirty eyes of 30 children with ectopia lentis were evaluated. A statistically significant correlation was found between age and the CTC. The CTC could be predicted by the equation CTC = 0.1313 × Age + 0.9666. No statistically significant correlations were found between CTC and WTW, CTC and AL, WTW and AL, or WTW and age. CONCLUSION: Endoscopy is useful for precisely suturing intraocular lens haptics in the real ciliary sulcus. Age can be used as an equivalent parameter for prediction of the true ciliary sulcus location.

Mutation spectrum and genotype-phenotype correlations in Chinese congenital ectopia lentis patients.

PURPOSE: To identify the spectrum and frequency of mutations in congenital ectopia lentis (CEL) and to investigate the correlations between genotype and clinical phenotype in Chinese CEL patients. METHODS: Ninety-three participants with CEL were enrolled from March 2017 to April 2020. Ocular and systemic examinations were performed for each included patient. Genomic DNA from the included patients was analysed by whole-exome sequencing to detect mutations. Clinical manifestations were compared for different mutation subgroups. RESULTS: Gene mutations were detected in 79 patients. Sixty-five were FBN1-associated, and most were related to Marfan syndrome (MFS). The FBN1 mutations mainly consisted of missense mutations (49/65) and were concentrated in the 5' region. Probands with missense mutations tend to show high corneal astigmatism (χ2 = 3.98, P = 0.046) and severe lens dislocation (t = 2.90, P = 0.006) compared to premature termination codon (PTC) mutations. CONCLUSIONS: Most Chinese CEL patients were identified as having FBN1 mutations. Those with missense mutations commonly showed severe ocular phenotypes; therefore, reinforced follow-up and long-term observation are required. These correlations implicated the crucial role of missense and cysteine-involving mutations in ocular phenotypes, which might be explained by dominant-negative and nonsense-mediated mRNA decay (NMD).