Genotype Impacts Axial Length Growth in Pseudophakic Eyes of Marfan Syndrome.

Purpose: The purpose of this study was to investigate the relationship between axial length (AL) growth and FBN1 genotype in patients with Marfan syndrome (MFS) after lens surgery and customize the selection of intraocular lens (IOL) power. Methods: Patients with MFS who had lens surgery and primary IOL implantation received panel-based next-generation sequencing (NGS). The rate of axial length growth (RALG) was calculated using pre- and postoperative AL measurements and corrected log10-transformed age. A multivariable regression model of RALG was developed after analyzing the effect of FBN1 genotypes and confounding factors. Results: A total of 139 probands of MFS with a median age at lens surgery of 6.25 years (interquartile range [IQR] = 4.67, 12.50 years) were followed up for a median duration of 2.08 years (IQR = 1.16, 3.00 years). The AL growth curve between the age of 3 and 15 years old was logarithmic. Dominant-negative (DN) variants affecting the disulfide-bridge forming cysteines and the conserved residues for calcium-binding had significantly higher RALG than DN variants affecting other structures (P = 0.001) but comparable to that of haplo-insufficiency variants (P = 1.000). Pre-operative AL (b = 0.563, P = 0.011) and genotype constant (b = 2.603, P = 0.011) were significantly associated with RALG in the final model. A Python-based calculator, Marfan IOL Calculator version 2.0, was programmed using the RALG to predict postoperative AL and customize IOL selection based on the ocular biometric parameters and FBN1 genotype. Conclusions: FBN1 genotype impacted the growth of AL in patients with MFS after IOL implantation. Knowing the FBN1 genotype could help cataract surgeons to customize IOL selection.

Amelioration of olfactory dysfunction in a mouse model of Parkinson's disease via enhancing GABAergic signaling.

BACKGROUND: Olfactory dysfunction is among the earliest non-motor symptoms of Parkinson's disease (PD). As the foremost pathological hallmark, α-synuclein initiates the pathology in the olfactory pathway at the early stage of PD, particularly in the olfactory epithelium (OE) and olfactory bulb (OB). However, the local neural microcircuit mechanisms underlying olfactory dysfunction between OE and OB in early PD remain unknown. RESULTS: We observed that odor detection and discrimination were impaired in 6-month-old SNCA-A53T mice, while their motor ability remained unaffected. It was confirmed that α-synuclein increased and accumulated in OB but not in OE. Notably, the hyperactivity of mitral/tufted cells and the excitation/inhibition imbalance in OB were found in 6-month-old SNCA-A53T mice, which was attributed to the impaired GABAergic transmission and aberrant expression of GABA transporter 1 and vesicular GABA transporter in OB. We further showed that tiagabine, a potent and selective GABA reuptake inhibitor, could reverse the impaired olfactory function and GABAergic signaling in OB of SNCA-A53T mice. CONCLUSIONS: Taken together, our findings demonstrate potential synaptic mechanisms of local neural microcircuit underlying olfactory dysfunction at the early stage of PD. These results highlight the critical role of aberrant GABAergic signaling of OB in early diagnosis and provide a potential therapeutic strategy for early-stage PD.

Morphometric Assessment of the Ciliary Body in Patients With Marfan Syndrome and Ectopia Lentis: A Quantitative Study Using Ultrasound Biomicroscopy.

PURPOSE: To explore the biometric characteristics of the ciliary body in patients with Marfan syndrome (MFS) and ectopia lentis (EL). DESIGN: Cross-sectional study. METHODS: Seventy-two consecutive patients with MFS and EL and 72 nondiseased control subjects were recruited. Ciliary body biometric parameters such as ciliary muscle cross-sectional area at 2000 µm from the scleral spur (CMA2000), ciliary muscle thickness at 1000 µm from the scleral spur (CMT1000), and maximum ciliary body thickness (CBTmax) were measured from multiple directions with ultrasound biomicroscopy (UBM). The relationship between ciliary body parameters and other ocular characteristics was also evaluated. RESULTS: Average CMA2000, CMT1000, and CBTmax were 0.692 ± 0.015 mm2, 0.405 ± 0.010 mm, and 0.855 ± 0.023 mm in eyes of patients with MFS, respectively, and were significantly smaller than these values in control subjects (all P < .001). The prevalence of ciliary body thinning was 22.2% in the MFS group vs 0 in the control group (P < .001); eyes with more severe EL had smaller CMA2000 (P = .050), thinner CMT1000 (P = .022), and shorter CBTmax (P = .015). Patients with microspherophakia (MSP) had even smaller CMA2000 (P = .033) and CMT1000 (P = .044) than those without MSP. The most common subluxation direction was in the superonasal quadrant (n = 25; 39.7%), which probably correlates with the thinnest CMT1000 in the inferotemporal quadrant (P = .005). CONCLUSIONS: Patients with MFS and EL had thinner ciliary muscles, shorter ciliary processes, and a higher prevalence of ciliary body thinning, especially those with MSP. Both the extent and direction of subluxation were associated with ciliary body biometry..

Predicting axial length in patients with Marfan syndrome and ectopia lentis after modified capsular tension ring and intraocular lens implantation.

PURPOSE: To predict the growth of axial length (AL) in patients with Marfan syndrome (MFS) and ectopia lentis (EL). SETTING: Eye and ENT Hospital of Fudan University, Shanghai, China. DESIGN: Consecutive retrospective case series. METHODS: Eyes were evaluated that had modified capsular tension ring and intraocular lens (IOL) implantation. The rate of AL growth (RALG) was calculated using AL divided by log10-transformed age. A multivariate linear regression model of RALG was developed after validation. RESULTS: 128 patients with MFS and EL were enrolled with a median follow-up duration of about 3 years. RALG was independent of age between 3 years and 15 years old ( P = .799) and decreased to 0 thereafter ( P = .878). Preoperative AL was associated with RALG in patients under 15 years old ( P = .003). Beta values for the final model of RALG were as below: intercept (-9.794) and preoperative AL (0.664). The postoperative AL was predicted as: postAL = preAL + RALG × log 10 ([postAge + 0.6]/[preAge + 0.6]). The mean prediction error was -0.003 (95% CI, -0.386 to 0.3791) mm and the mean absolute percentage error was 1.93% (95% CI, 0.73% to 3.14%). A Python-based calculator was developed to use the predicted AL in selecting IOL power and setting undercorrection. CONCLUSIONS: The AL growth of patients with MFS followed a logarithmic pattern and ceased at about age 15. A prediction model of postoperative AL was established for individual MFS patients between 3 and 15 years old, which could potentially optimize the IOL power selection.

Supracapsular scleral sutured intraocular lens implantation in anterior segment dysgenesis patients with ectopia lentis.

OBJECTIVE: To describe a new strategy to manage ectopia lentis in ASD patients assessing the visual outcomes and safety of supracapsular scleral sutured intraocular lens implantation and analyzing the accuracy of different intraocular lens (IOL) power calculation formulae. METHODS: Eight patients with ASD (13 eyes) were underwent supracapsular scleral suture fixation of posterior chamber (PC) IOL without capsular extirpation. The preoperative and postoperative clinical features were compared. The prediction error values from four formulae (SRK/T, Holladay 1, Hoffer Q, Haigis), with or without Wang-Koch (WK) adjustment, were calculated for the cases. RESULTS: Zonulodialysis and premature cataracts could be the main reason for the decreased vision in patients with ASD. There was a significant improvement in best corrected visual acuity on 3-month follow-up after applying supracapsular scleral suture fixation of PC IOL. The prediction errors of the different formulae showed a slight tendency towards postoperative myopia. The Haigis formula with WK adjustment showed the best performance. CONCLUSIONS: Supracapsular scleral suture fixation of IOLs for retaining the capsule-zonule barrier is a good option for ASD patients. The Haigis formula is recommended for ASD patients treated with supracapsular scleral suture fixation of IOLs. The predicted IOL power should be reduced based on the effect of the new anatomic position of the IOL to achieve a satisfactory visual outcome.

Biallelic ADAMTSL4 variants in a Chinese cohort of congenital ectopia lentis: Implications for genotype-phenotype relationships.

ADAMTSL4 variants are one of the common causes of congenital ectopia lentis (EL), reported ocular comorbidities of which include iris anomalies, cataract, and glaucoma. However, a genotype-phenotype correlation has not been established. Potentially pathogenic ADAMTSL4 variants were screened from a Chinese cohort of congenital EL using panel-based next-generation sequencing followed by multiple bioinformatics analyses. The genotype-phenotype correlation was assessed via a systematic review of ADAMTSL4 variants within our data and those from the literature. A total of 12 variants of ADAMTSL4, including seven frameshift variants, one nonsense variant, two splicing variants, and two missense variants, were found in nine probands. Combing genetic and clinical information from 72 probands in the literature revealed 37 ADAMTSL4 variants known to cause EL, and the ethnic difference was prominent. The lens was inclined to dislocate inferior temporally (22, 27.16%), while the pupil was always located oppositely (9, 81.82%). Several anterior segments anomalies were identified, including ectopia pupillae (15, 18.52%), persistent pupillary membrane (9, 11.10%), poor pupil dilation (4, 30.8%), cataract (13, 24.10%), and glaucoma (8, 13.33%). Genotype-phenotype analysis revealed that truncation variants had higher risks of combined iris anomalies, including either ectopia pupillae or a persistent pupillary membrane (p = 0.007). The data from this study not only extend our knowledge of the ADAMTSL4 variant spectrum but also suggest that deleterious variants of ADAMTSL4 might be associated with severe ocular phenotypes.

Mutation analysis of SUOX in isolated sulfite oxidase deficiency with ectopia lentis as the presenting feature: insights into genotype-phenotype correlation.

BACKGROUND: Isolated sulfite oxidase deficiency (ISOD) caused by sulfite oxidase gene (SUOX) mutations is a rare neurometabolic disease associated with ectopia lentis (EL). However, few genotype-phenotype correlations have been established yet. METHODS: Potentially pathogenic SUOX mutations were screened from a Chinese cohort of congenital EL using panel-based next-generation sequencing and analyzed with multiple bioinformatics tools. The genotype-phenotype correlations were evaluated via a systematic review of SUOX mutations within our data and from the literature. RESULTS: A novel paternal missense mutation, c.205G > C (p.A69P), and a recurrent maternal nonsense mutation, c.1200 C > G (p.Y400*), of SUOX were identified in a 4-year-old boy from 312 probands. The biochemical assays manifested elevated urine sulfite and S-sulfocysteine accompanied by decreased homocysteine in the blood. The patient had bilateral EL and normal fundus, yet minimal neurological involvement and normal brain structure. Molecular modeling simulation revealed the p.A69P mutant had an unstable structure but an unchanged affinity for sulfite, while the truncated p.Y400* mutant showed decreased binding capacity. Genotype-phenotype analysis demonstrated patients with biallelic missense mutations had milder symptoms (P = 0.023), later age of onset (P < 0.001), and a higher incidence of regression (P = 0.017) than other genotypes. No correlations were found regarding EL and other neurological symptoms. CONCLUSION: The data from this study not only enrich the known mutation spectrum of SUOX but also suggest that missense mutations are associated with mild and atypical symptoms.

Genotype-phenotype correlations of marfan syndrome and related fibrillinopathies: Phenomenon and molecular relevance.

Marfan syndrome (MFS, OMIM: 154700) is a heritable multisystemic disease characterized by a wide range of clinical manifestations. The underlying molecular defect is caused by variants in the FBN1. Meanwhile, FBN1 variants are also detected in a spectrum of connective tissue disorders collectively termed as 'type I fibrillinopathies'. A multitude of FBN1 variants is reported and most of them are unique in each pedigree. Although MFS is being considered a monogenic disorder, it is speculated that the allelic heterogeneity of FBN1 variants contributes to various manifestations, distinct prognoses, and differential responses to the therapies in affected patients. Significant progress in the genotype-phenotype correlations of MFS have emerged in the last 20 years, though, some of the associations were still in debate. This review aims to update the recent advances in the genotype-phenotype correlations of MFS and related fibrillinopathies. The molecular bases and pathological mechanisms are summarized for better support of the observed correlations. Other factors contributing to the phenotype heterogeneity and future research directions were also discussed. Dissecting the genotype-phenotype correlation of FBN1 variants and related disorders will provide valuable information in risk stratification, prognosis, and choice of therapy.

Comparison of Accuracy in Keratometries Measured by Different Camera Devices for Predicting the Intraocular Lens Power in Lens-Dislocated Patients.

INTRODUCTION: This is a cross-sectional cohort study focused on assessing the influence of ocular biometric parameters of different camera devices for accurately predicting the intraocular lens (IOL) power in the congenital ectopia lentis (EL) patients. METHODS: This study includes a total of 91 eyes of 60 patients with congenital EL from June 2018 to April 2021. All patients underwent lens subluxation surgery with Cionni modified capsular tension rings (MCTR) implantation. Ocular parameters measured by partial coherence interferometry (IOLMaster 700, Carl Zeiss Meditec AG, Jena, Germany) and rotating Scheimpflug camera (Pentacam HR system, Oculus Optikgeräte GmbH, Wetzlar, Germany) were acquired from the database. The authenticity of the different keratometries (K) were analyzed by comparing the prediction error in spherical equivalent under controlled formula SRK/T, Haigis, and after Wang-Koch (WK) adjustment. RESULTS: We observed significant greater K values were obtained in IOLMaster than Pentacam, resulting in more significant hyperopia error while calculating SRK/T. The IOL power calculated with the total corneal refractive power (TCRP) from Pentacam revealed the highest prediction accuracy, indicating that TCRP is the closest to the actual refractive power of the cornea. However, in an exceptional case for long eye patients, total keratometry from IOLMaster was better recommended when using formula Haigis with WK adjustment. CONCLUSIONS: For most instances, TCRP is the best-recommended source of K value while calculating IOL power for EL patients. However, the total keratometry from IOLMaster preferably fits for long eye patients, who require WK adjustment for Haigis formula.

Biometric and Structural Ocular Manifestations of Anterior Megalophthalmos.

Objective: The aim of this study was to examine the biometric ocular manifestations and structural ocular features of anterior megalophthalmos (AM). Methods: Fifteen patients with AM (30 eyes) from the Eye & ENT Hospital of Fudan University were included. The age-matched control group consisted of 30 participants (30 eyes) who underwent Pentacam HR and IOLMaster 700 measurements for one normal eye. Data on demographics, biometric manifestations, and genotypes were carefully compared. Results: A total of 15 patients with AM and 30 control patients were enrolled. There were no differences in age (37.27 ± 19.1 vs. 31.43 ± 19.69 years, P = 0.249) between these two groups. AM eyes were characterized by premature cataracts (11/30, 36.67%) and zonular weakness with lens subluxation (22/30, 73.33%) compared with the control group. Notably, 20 of the 30 AM eyes (66.67%) had significant posterior iris bowing, and 16 of the 30 AM eyes (53.33%) showed an enlarged ciliary ring on ultrasound biomicroscopy (UBM). Mean corneal curvature was lower in the AM eyes (42.01 ± 2.06 D vs. 43.14 ± 1.38 D, P = 0.023). There was no significant difference in corneal pachymetry and central endothelial cell count between the AM and control groups. Significant differences were found in terms of the anterior chamber and white-to-white (WTW) among the Pentacam HR and IOLMaster 700 in patients with AM (P < 0.05). The difference was 0.53 ± 0.48 mm and 0.36 ± 0.14 mm, respectively (P < 0.001). Conclusion: The results of this cohort study conclude the biometric and structural ocular manifestations in Chinese cohorts. Posterior iris bowing (66.67%) and lens subluxation (73.33%) are the most characteristic findings in patients with AM with anatomical abnormalities of megalocornea and a deep anterior chamber, although corneal biometric manifestations of AM included flatter cornea and lower total corneal astigmatism. The knowledge of ocular manifestations of AM is important for diagnosis and preparation for the operation in advance to avoid intraoperative and postoperative complications. Significant differences were found in the anterior chamber and WTW values between the Pentacam HR and IOLMaster 700. Thus, we suggest that various examinations should be carefully considered before determining an AM diagnosis.

Phacoemulsification Combined With Supra-Capsular and Scleral-Fixated Intraocular Lens Implantation in Microspherophakia: A Retrospective Comparative Study.

Background: Microspherophakia (MSP) is a rare ocular condition, the lens surgery of which is complicated by both insufficient zonules and undersized capsule. Methods: This study included MSP eyes managed with phacoemulsification combined with supra-capsular and scleral-fixated intraocular lens implantation (SCSF-IOL) and made the comparison with those treated by transscleral-fixated modified capsular tension ring and in-the-bag intraocular lens implantation (MCTR-IOL). Results: A total of 20 MSP patients underwent SCSF-IOL, and 17 patients received MCTR-IOL. The postoperative best corrected visual acuity was significantly improved in both groups (P < 0.001), but no difference was found between the groups (P = 0.326). The IOL tilt was also comparable (P = 0.216). Prophylactic Nd:YAG laser posterior capsulotomy was performed 1 week to 1 month after the SCSF-IOL procedure. In the SCSF-IOL group, two eyes (10.00%) needed repeated laser treatment and one eye (5.00%) had a decentered capsule opening. Posterior capsule opacification was the most common complication (6, 35.29%) in the MCTR group. No IOL dislocation, secondary glaucoma, or retinal detachment was observed during follow-up. Conclusions: SCSF-IOL is a viable option for managing MSP and is comparable with the MCTR-IOL. Nd:YAG laser posterior capsulotomy was necessary to prevent residual capsule complications after the SCSF-IOL procedure.

Combination of Panel-based Next-Generation Sequencing and Clinical Findings in Congenital Ectopia Lentis Diagnosed in Chinese Patients.

PURPOSE: To evaluate the diagnostic yield of congenital ectopia lentis (EL) in a Chinese cohort by combining panel-based next-generation sequencing with clinical findings. DESIGN: A cohort study. METHODS: In total, 175 patients with congenital EL and their available family members (n = 338) were enrolled. All patients with congenital EL underwent genetic testing. Genotype-phenotype analyses were conducted to assess the biometric and structural ocular manifestations of congenital EL. RESULTS: In total, 175 patients with congenital EL and 338 of their relatives were included in this study. In these patients, 92.57% (162 of 175) of disease-related variants were detected in FBN1 (83.43%), CPAMD8 (1.71%), COL4A5 (0.57%), ADAMTSL4 (3.43%), LTBP2 (1.71%), and CBS (2.29%). Based on genetic and clinical findings, the primary diagnostic rate was increased to 40.57% from 19.43% with the exception of the 91 diagnoses of potential Marfan syndrome, with a new diagnostic strategy for congenital EL, thus having been developed. Within this group of patients harboring FBN1 mutations, 16.44% (19 of 141) probands were diagnosed with EL syndrome and 2.13% (3 of 141) were diagnosed with Marfan syndrome. CONCLUSIONS: The results of this cohort study expand the genomic landscape associated with congenital EL in Chinese cohorts. FBN1 mutations represent the most common cause of congenital EL in this population, and we have developed a new diagnostic strategy for congenital EL subtypes via the use of a well-designed panel-based next-generation sequencing that can be used to efficiently and precisely diagnose patients with congenital EL in a cost-effective manner.

Correlation between FBN1 mutations and ocular features with ectopia lentis in the setting of Marfan syndrome and related fibrillinopathies.

Mutations of fibrillin-1 (FBN1) have been associated with Marfan syndrome and pleiotropic connective tissue disorders, collectively termed as "type I fibrillinopathy". However, few genotype-phenotype correlations are known in the ocular system. Patients with congenital ectopia lentis (EL) received panel-based next-generation sequencing, complemented with multiplex ligation-dependent probe amplification. In a total of 125 probands, the ocular phenotypes were compared for different types of FBN1 mutations. Premature termination codons were associated with less severe EL and a thinner central corneal thickness (CCT) than the inframe mutations. The eyes of patients with mutations in the C-terminal region had a higher incidence of posterior staphyloma than those in the middle and N-terminal regions. Mutations in the TGF-ß-regulating sequence had larger horizontal corneal diameters (white-to-white [WTW]), higher incidence of posterior staphyloma, but less severe EL than those with mutations in other regions. Mutations in the neonatal region were associated with thinner CCT. Longer axial length (AL) was associated with mutations in the C-terminal region or TGF-ß regulating sequence after adjusting for age, EL severity, and corneal curvature radius. FBN1 genotype-phenotype correlations were established for some ocular features, including EL severity, AL, WTW, CCT, and so forth, providing novel perspectives and directions for further mechanistic studies.

Analysis of Axial Length in Young Patients with Marfan Syndrome and Bilateral Ectopia Lentis by Z-Scores.

INTRODUCTION: Marfan syndrome (MFS) is characterized by ectopia lentis (EL) and elongated axial length (AL). The characteristics of AL in young patients with MFS and bilateral EL before the lens surgery are not fully understood. METHODS: This study reviewed MFS patients under 20 years old with bilateral EL from January 2015 to October 2020. The Z-scores were introduced in terms of the number of standard deviations from the mean of age-matched normative data. Using Z-scores, the distribution of AL and influence factors were evaluated. The correlations between AL and other biometrics were analyzed. RESULTS: We reviewed 183 patients and enrolled both eyes. The mean age was 8.44 ± 4.69 years. About 36% of the patients were children under 6 years old. The median AL increased from 23.16 mm under 5 years old to 26.20 mm in the 16-20 age group, and when plotted, the trend presented a logarithmic curvature (R2 = 0.145, p < 0.001). The median Z-AL score was 1.24. One-third of eyes had Z-score <0. About 20% of the patients had AL difference over 1 mm between the right and left eyes, and the right one had longer Z-AL scores (p = 0.013). The eye complicated with megalocornea (10, 7.04%) had larger Z-AL scores (4.72 ± 3.51 vs. 1.10 ± 2.25, p = 0.002). A positive correlation was found between Z-AL and Z-corneal curvature radius (r = 0.265, p < 0.001). CONCLUSION: Young patients with bilateral EL but small AL should not be excluded from MFS without systematic examination. The age-adjusted Z-score will facilitate further study of the individual variations in AL across different ages.

Lens Biometry in Congenital Lens Deformities: A Swept-Source Anterior Segment OCT Analysis.

Aims: To investigate the lens biometric parameters in congenital lens deformities, using a novel technique of swept-source anterior segment optical coherence tomography (SS-ASOCT). Methods: This prospective study included patients with microspherophakia (MSP), coloboma lentis (CL), and posterior lenticonus (PL). For this cohort, 360-degree high-resolution lens images were obtained using the latest SS-ASOCT (CASIA2, Tomey Corp, Nagoya, Japan). The lens biometric parameters were calculated by the CASIA2 built-in software for anterior lens radius (ALR), posterior lens radius (PLR), anteroposterior distance (APD), anterior chamber depth (ACD), equatorial diameter (Eq Dia), rear projection length (RPL), and maximum diameter of the lesion (MDL). Results: This study included two eyes each with MSP and CL and one eye with PL. The lens of MSP was spherical and posteriorly dislocated, with decreased ALR and PLR, Eq Dia, but increased APD. In patients with CL, the coloboma was isolated, bilateral, inferior, and located toward the maldeveloped ciliary body. High astigmatism was mainly lenticular, and this was calculated by the ALR and PLR. Regarding the site of coloboma, a significant decrease in ALR was observed, while the PLR and APD were not affected. The PL eyes had a cone-shaped protrusion of the posterior lens surface with a subtle cataractous region around the apex. An extremely high posterior surface curvature was observed with a mean PLR of 1.67 mm. The RPL and MDL were about 1.80 and 0.4 mm, respectively, which were homogenous at different sections. Conclusions: The CASIA2 is a valuable option for in vivo crystalline lens measurement for congenital lens deformities, enabling the accurate diagnosis and providing illuminating insights into the pathogenesis of MSP, CL, and PL.