Combined trabeculotomy-trabeculectomy for glaucoma after congenital cataract surgery: long-term results

OBJECTIVE

The aim of this study was to report on the long-term (>5 years) results of surgery for glaucoma after congenital cataract surgery.

DESIGN

Retrospective.

METHODS

A chart review was conducted of all children operated on for glaucoma after congenital cataract surgery in the Pediatric Ophthalmology Service of the Ophthalmology Department of Alexandria main University Hospital in Alexandria, Egypt, between 2005 and 2014 who completed 5 years of follow-up. Demographic, clinical, and operative data were retrieved from the medical records. Success was defined by stability and (or) reversal of optic nerve cupping in relation to presentation and, if this information was not available, by an intraocular pressure (IOP) less than the presenting IOP and less than 16 mm Hg with (true) or without (qualified) IOP-lowering therapy.

RESULTS

The records of 48 children were reviewed. Thirty-two eyes of 24 children had completed at least 5 years of follow-up and were included in the study. The mean age (±SD) of the study children was 11.6 ± 11.3 months (range, 3.2-52.0 months) at presentation, and the mean (±SD) follow-up was 105.5 ± 31.4 months (range, 60-156 months). Of 47 glaucoma surgical procedures in total, combined angle and filtering surgery with antimetabolite was the most common procedure performed (n = 30;63.8%). Annual success percentages from the fifth year onward to the thirteenth year were 69.6%, 68.8%, 77.8%, 50.0%, 71.4%, 60.0%, 50.0%, 83.3%, and 50.0%, respectively.

CONCLUSIONS

Surgery for glaucoma after congenital cataract surgery remains safe and successful for 13 years after surgery.

Contact lenses in paediatric aphakia in the Netherlands; A multicentre retrospective chart study

PURPOSE

The main aim of this study was to evaluate the type, parameters, loss and complications of contact lenses (CLs) in the treatment of paediatric aphakia over a 10-year period.

METHODS

This retrospective multicentre chart review included the files of aphakic CL wearers under the age of 9 years old that were treated between 2008 and 2018. Patients with traumatic aphakia and scarring of the cornea were excluded. The following data were collected; demographic data, cataract type (congenital or secondary), CL type, parameters and wearing time, reason for replacement and discontinuation of the CLs, visual acuity (VA), prophylactic use of antibiotics (ABs), and complications.

RESULTS

Ninety-one aphakic children (132 eyes) were fitted with soft CLs. The median age of cataract extraction was 10.50 weeks (interquartile range (IQR) 7,15) in the congenital cataract group and 112 weeks (IQR 41,285) in the secondary cataract group. At the initial fitting a silicone elastomer CL was fitted in 86 % and a silicone hydrogel CL in 12 %, the remaining 2 % were mixed CL types. The median CL power at baseline was + 29 D (IQR 25,32) and after 3 years of wear the median power had shifted significantly to + 20 D (IQR 17,26), P < 0.001. A total of 1083 extra CL replacements were needed of which 414 in the first year of wear. Of these 414 replacements almost half (46 %;n = 191) were due to loss of the CL. Complications developed in 8 (9 %) cases and 7 (8 %) patients discontinued CL wear.

CONCLUSION

This paper confirms that paediatric aphakia can be successfully treated with soft CLs with low rates of complications and discontinuation encountered. Unscheduled CL replacements due to loss are a concern, especially in the first year, and are straining for both the care giver and medical system. Attentive care and clear information is advised during the first year of CL wear.

Case report of fetus with Lowe syndrome: Expanding the prenatal phenotype

Oculocerebrorenal syndrome (Lowe syndrome) is a rare X-linked disorder affecting 1/500,000 males that most frequently affects the eyes, central nervous system, and kidneys. Phenotypic presentation includes congenital cataracts, developmental delay, intellectual disability, and Fanconi-type renal dysfunction. Lowe Syndrome is caused by hemizygous loss of function variants in the OCRL gene. While individuals may live into the third and fourth decade of life, some will die in the first few years of either renal failure or infection. While early diagnosis is important, few cases have documented the prenatal phenotype of this condition, which has included bilateral cataracts and variable neurological abnormalities. We report a case of a family with an extensive history of congenital cataracts, immune compromise, and neonatal death in male members. The fetus was found to have a unilateral cataract, mild ventriculomegaly, vertebral anomalies, and an underlying diagnosis of Lowe Syndrome with a mutation in OCRL at c.2582-1G>C (IVS23-1G>C).

A novel single-base deletional mutation of MIP impairs protein distribution and cell-to-cell adhesion in autosomal dominant cataracts in a Chinese family

Congenital cataracts are the leading cause of irreversible visual disability in children, and genetic factors play an important role in their development. In this study, targeted exome sequencing revealed a novel single-base deletional mutation of MIP (c.301delG; p.Ala101Profs*16) segregated with congenital punctate cataract in a Chinese family. The hydrophobic properties, and secondary and tertiary structures for truncated MIP were predicted to affect the function of protein by bioinformatics analysis. When MIP-WT and MIP-Ala101fs expression constructs were singly transfected into HeLa cells, it was found that the mRNA level showed no significant difference, while the protein level of the mutant was remarkably reduced compared to that of the wild-type MIP. Immunofluorescence images showed that the MIP-WT was principally localized to the plasma membrane, whereas the MIP-Ala101fs protein was aberrantly trapped in the cytoplasm. Furthermore, the cell-to-cell adhesion capability and the cell-to-cell communication property were both significantly reduced for MIP-Ala101fs compared to the MIP-WT (all *p < 0.05). This is the first report of the c.301delG mutation in the MIP gene associated with autosomal dominant congenital cataracts. We propose that the cataract is caused by the decreased protein expression and reduced cell-to-cell adhesion by the mutant MIP. The impaired trafficking or instability of the mutant protein, as well as compromised intercellular communication is probably a concurrent result of the mutation. The results expand the genetic and phenotypic spectra of MIP and help to better understand the molecular basis of congenital cataracts.

Couching of cataractous lens in microphthalmic eyes with irido-fundal coloboma: revisiting the historical technique

PURPOSE

Cataract surgery in microphthalmic eyes is challenging due to anatomical restraints, hard bulky nucleus. This series aims to evaluate the safety and efficacy of couching of intraocular lens in irido-fundal coloboma with microphthalmos.

SETTING

Tertiary care centre in South India.

DESIGN

Retrospective non-comparative study in eyes with irido-fundal coloboma, corneal diameter < 7 mm and brown cataract. Visual acuity less than 6/60 in other eye.

METHODS

Anterior chamber entry made, zonules broken and lens dislocated into the vitreous cavity in a controlled manner. Baseline Clinico-demographic details, corrected distance visual acuity (CDVA), Intra-ocular pressure (IOP), corneal diameter, axial length, lens status and post-surgery CDVA, IOP and complications recorded and followed up for atleast 6 months.

RESULTS

Fifteen eyes of 15 subjects were evaluated with a mean age 49.4 ± 10.9 years. At baseline, mean IOP 14.5 ± 3.8 mmHg, mean axial length 19.3 ± 0.5 mm, mean corneal diameter was 6.5 ± 0.34 mm and CDVA 2 logMAR which improved to 1.5 logMAR at 3 months (p value 0.002). Transient spike in IOP in 33.3% subjects was medically managed with no significant difference in IOP (p > 0.05) at baseline (14.5 ± 3.8 mmHg), 3 months post-surgery (16 ± 2.8 mmHg) and 6 months post-surgery (14.9 ± 2.5 mmHg). One patient underwent re-couching. No other major complications were noted.

CONCLUSION

Couching of cataractous lens is an effective and safe method in microphthalmic eyes with irido-fundal coloboma as last resort procedure, where no other surgical procedure may work. It provides an ambulatory gain of visual acuity in previously non-ambulatory subjects. Corneal measurements help in determining the subset of patients where couching offers viable option.

Cataract surgery and artificial iris implantation in patient with oculocutaneous albinism: a case report

We present a case report detailing the successful phacoemulsification surgery with artificial iris implantation for two individuals with oculocutaneous albinism. These women suffered from cataracts, resulting in reduced visual acuity and heightened photophobia due to iris pigmentary epithelium deficiency. The patients underwent phacoemulsification along with prosthetic artificial iris implantation into the posterior chamber. This intervention resulted in improved visual acuity, reduced photophobia and glare, and an overall enhanced quality of life. Our report highlights two cases of successful phacoemulsification and artificial iris implantation in patients with oculocutaneous albinism and cataracts, leading to improved visual acuity, reduced photophobia, and enhanced quality of life. Notably, there are no prior records in South American literature of cataract surgery combined with artificial iris implantation for oculocutaneous albinism patients up to the time of this publication.

Management of Contact Lenses and Visual Development in Pediatric Aphakia

Congenital cataract is among the main causes of treatable vision loss in childhood. The first weeks and months of life are a critical time for the development of vision. Therefore, early cataract surgery and effective multifaceted treatment of the resulting aphakia in the early stages of life are of great value for the management of vision development. Among the treatment models, contact lenses (CL) have an important place in infancy and early childhood up to the age of 2 years. Although good visual gains were not considered very likely, especially in unilateral aphakia, important steps have been taken in the treatment of pediatric aphakia thanks to the surgical techniques developed over time and the increasing experience with optical correction systems, especially CLs. This review examines current developments in the types of CL used in pediatric aphakia, their application features, comparison with other optical systems, the features of amblyopia treatment in the presence of CL, and the results obtained with family compliance to CL wear and occlusion therapy in the light of existing studies.

[A comparative study of rigid gas permeable corneal contact lenses versus frame glasses for refractive correction of postoperative aphakic eyes after congenital cataract surgery in infants and children]

Objective: The aim of this paper is to compare the refractive correction effects of rigid gas permeable contact lenses (RGPCL) and spectacle correction in children with aphakia after congenital cataract surgery. Methods: This was a prospective non-randomized controlled trial. Children with aphakic eyes after congenital cataract surgery, who underwent vision correction in the Strabismus and Pediatric Ophthalmology Clinic of Beijing Tongren Hospital affiliated with Capital Medical University from April 2012 to November 2019, were continuously collected. Those who voluntarily chose to wear RGPCL for refractive correction were included in the experimental group. Patients with monocular disease were in trial group 1, and patients with binocular disease were in trial group 2. Patients who chose to wear frame glasses for refractive correction were included in the control group. Patients with monocular disease were in control group 1, and patients with binocular disease were in control group 2. Regional origin, medical history, and family information were collected at the first diagnosis. During the follow-up, adverse reactions occurring during the process of wearing glasses were recorded. The Teller acuity card was used for visual examination to obtain the best-corrected visual acuity and convert it into the logarithm of the minimum resolution angle. The degree of nystagmus was determined according to the amplitude and frequency of nystagmus. Treatment cost, treatment compliance, and the reasons for adopting or not adopting RGPCL were analyzed through a questionnaire completed by the parents of children with RGPCL. Results: A total of 203 children (344 eyes) who underwent congenital cataract surgery were included, including 124 males (210 eyes) and 79 females (134 eyes). The age range was 3 to 36 months. There were 28 cases in the experimental group, including 19 cases in trial group 1 and 9 cases in trial group 2. There were 175 cases in the control group, including 43 cases in control group 1 and 132 cases in control group 2. Except for 6 months of age, the visual acuity of the experimental group was better than that of the control group, and the differences were statistically significant (P<0.05). The visual acuity of children in trial group 1 was better than that of children in control group 1 at the same age. Among them, at 12 months of age [1.54 (1.27, 1.97), 1.84 (0.97, 2.12)], 18 months of age [1.27 (0.97, 1.84), 1.84 (0.97, 2.12)], 24 months of age [1.54 (1.27, 1.84), 1.84 (0.97, 2.12)], and 30 months old [0.97 (0.66, 1.27), 1.54 (0.66, 2.12)], the difference was statistically significant (P<0.001). The visual acuity of children in trial group 2 was better than that in control group 2 at the same age. Among them, at 18 months old [1.27 (0.97, 1.54), 1.27 (0.66, 2.12)], 24 months old [0.97 (0.66, 1.27), 1.27 (0.66, 2.12)], and 30 months old [1.27 (0.66, 2.12)], the difference was statistically significant (P<0.05). The remission rate of nystagmus in the experimental group was 8/9 (8 cases), the remission rate of nystagmus in the control group was 34.40% (32 cases), and the exacerbation rate was 29.03% (27 cases). The average annual cost of the experimental group was 25 125 yuan, and that of the control group was 2 511 yuan. Conclusions: RGPCL is a well-tolerated, safe, and effective treatment for infants and young children. The visual acuity and degree of nystagmus were significantly improved in children who wore RGPCL for aphakia refractive correction after congenital cataract surgery compared with spectacle correction.

In vivo quasi-elastic light scattering detects molecular changes in the lenses of adolescents with Down syndrome

Down syndrome (DS) is the most common chromosomal disorder in humans. DS is associated with increased prevalence of several ocular sequelae, including characteristic blue-dot cerulean cataract. DS is accompanied by age-dependent accumulation of Alzheimer's disease (AD) amyloid-β (Aβ) peptides and amyloid pathology in the brain and comorbid early-onset Aβ amyloidopathy and colocalizing cataracts in the lens. Quasi-elastic light scattering (QLS) is an established optical technique that noninvasively measures changes in protein size distributions in the human lens in vivo. In this cross-sectional study, lenticular QLS correlation time was decreased in adolescent subjects with DS compared to age-matched control subjects. Clinical QLS was consistent with alterations in relative particle hydrodynamic radius in lenses of adolescents with DS. These correlative results suggest that noninvasive QLS can be used to evaluate molecular changes in the lenses of individuals with DS.

Association of variants in GJA8 with familial acorea-microphthalmia-cataract syndrome

Congenital acorea is a rare disease with the absence of a pupil in the eye. To date, only one family and two isolated cases with congenital acorea have been reported. The gene associated with acorea has not been identified. In this study, we recruited a Chinese family acorea-microphthalmia-cataract syndrome. By analyzing the whole-exome sequencing (WES) data of this Chinese family, we revealed the association of a novel heterozygous variant, NM_005267.5:c.137G>A (p.G46E) in the gap junction protein alpha 8 (GJA8) gene encoding connexin 50 or CX50, with familial acorea-microphthalmia-cataract syndrome. Additionally, another variant, NM_005267.5:c.151G>A (p.D51N) in GJA8, was identified to co-segregate with this syndrome in an unrelated Japanese family. Ectopic expression of p.G46E and p.D51N mutant GJA8 genes in cultured cells caused protein mislocalization, suggesting that the p.G46E and p.D51N mutations in GJA8 impaired the function of the gap junction channels. These results established GJA8 as the first gene associated with familial acorea-microphthalmia-cataract syndrome.

Nonsense-mediated mRNA decay affects hyperactive root formation in oculo-facio-cardio-dental syndrome via up-frameshift protein 1

OBJECTIVES

Oculo-facio-cardio-dental (OFCD) syndrome is a rare X-linked genetic disorder caused by mutations in the BCL6 co-repressor (BCOR) and is mainly characterized by radiculomegaly (elongated dental roots). All BCOR mutations reported to date have been associated with premature termination codons, indicating that nonsense-mediated mRNA decay (NMD) might play a vital role in the pathogenesis of OFCD syndrome. However, the molecular mechanisms underlying NMD remain unclear. In this study, we investigated the involvement of up-frameshift protein 1 (UPF1), which plays a central role in NMD, in the hyperactive root formation caused by BCOR mutations.

METHODS

Periodontal ligament cells, isolated from a Japanese woman with a c.3668delC frameshift mutation in BCOR, and primary human periodontal ligament fibroblasts (HPdLFs) were used for an RNA immunoprecipitation assay to confirm the binding of UPF1 to mutated BCOR. Additionally, the effects of UPF1 on the BCOR transcription levels and corresponding gene expression were determined by performing relative quantitative real-time polymerase chain reactions.

RESULTS

RNA immunoprecipitation revealed that UPF1 binds to exon 9 of mutated BCOR. Additionally, UPF1 knockdown via siRNA upregulated the transcription of BCOR, whereas overexpression of wild-type and mutated BCOR with the same frameshift mutation in HPdLFs altered bone morphogenetic protein 2 (BMP2) expression.

CONCLUSIONS

Our findings indicate that BCOR mutations regulate the transcription of BCOR via UPF1, which may in turn regulate the expression of BMP2. NMD, caused by a c.3668delC mutation, potentially leads to an OFCD syndrome phenotype, including elongated dental roots.

Incidence of and risk factors for suspected and definitive glaucoma after bilateral congenital cataract surgery: a 5-year follow-up

AIMS

To report the incidence and associated risk factors for developing suspected and definitive glaucoma after bilateral congenital cataract (CC) removal with a 5-year follow-up.

METHODS

Secondary analysis of a prospective longitudinal cohort study. Bilateral CC patients who had undergone cataract surgery between January 2011 and December 2014 at Zhongshan Ophthalmic Centre were recruited. Suspected glaucoma was defined as persistent ocular hypertension requiring medical treatment. Definitive glaucoma was defined as accompanied by the progression of glaucomatous clinical features. According to postoperative lens status in 5 years follow-up: 130 eyes in the aphakia group; 219 in the primary intraocular lens (IOL) implantation group and 337 in the secondary IOL implantation group. The Kaplan-Meier survival and Cox regression analyses were used to explore the cumulative incidence and risk factors for suspected and definitive glaucoma.

RESULTS

Three hundred fifty-one children (686 eyes) with bilateral CCs were enrolled in the study. The mean age at surgery was 1.82±2.08 years, and the mean follow-up duration was 6.26±0.97 years. Suspected and definitive glaucoma developed at a mean time of 2.84±1.75 years (range 0.02-7.33 years) postoperatively. The cumulative incidence of suspected and definitive glaucoma was 9.97% (35 of 351 patients), including 6.12% (42 eyes) for definitive glaucoma and 2.48% (17 eyes) for suspected glaucoma. Microcornea (HR 4.103, p<0.0001), CC family history (HR 3.285, p=0.001) and initial anterior vitrectomy (HR 2.365 p=0.036) were risk factors for suspected and definitive glaucoma. Gender, age at surgery, intraocular surgery frequency, length of follow-up and frequency of neodymium-doped yttrium aluminumaluminium garnet laser were non-statistically significant. Primary IOL implantation was a protective factor (HR 0.378, p=0.007).

CONCLUSIONS

Identifying suspected and definitive glaucoma after bilateral CC surgery can lower the risk of secondary blindness in children. Patients with related risk factors need to pay more attention and thus reach early intervention and treatment during clinical practice. Primary IOL implantation may be a potential protective factor, need more clinical trials to be verified.

TRIAL REGISTRATION NUMBER

NCT04342052.

Predictive factors of occult cystobiliary fistulas during conservative treatment of hepatic hydatid cyst: a prospective study

BACKGROUND

Occult cystobiliary fistula (CBF) is a common complication of hepatic hydatid cyst (HHC). It is often the cause of high morbidity of conservative treatment of HHC. This study aimed to determine the predictive factors of occult CBF to establish the indications for the investigation and treatment of these CBFs.

METHODS

This was a prospective study that included all operated HHCs over a 3-year period. HHCs complicated with large CBFs were not included in the study. Systematic cholecystectomy and methylene blue test for all cysts were performed.

RESULTS

A total of 46 patients operated on with 113 cysts were included in this study. The median cyst size was 6.7 cm (IQR, 1-38). A total of 114 CBFs were detected in 51 cysts (45.1%). The postoperative course was simple in 95.0% of cases. The specific morbidity rate was 2.7%. In a bivariate study, absence of mass and abdominal pain on palpation, hemoglobin level >11.55 g/dL, negative hydatid serology, cyst size, absence of calcifications, vascular compression, existence of a single cyst, and localization at segment VIII were predictive factors of occult CBF. At the end of the multivariate study, cyst size was determined to be the only predictive factor for occult CBF. A threshold of 3 cm was used.

CONCLUSION

Cyst size is a major predictive factor for occult CBF.

Facial dysmorphism in congenital rubella syndrome

PURPOSE

To investigate the dysmorphic facial features in congenital rubella syndrome (CRS) and describe their associations with ocular and systemic features.

METHODS

The medical records of children diagnosed with CRS between 2016 and 2021 were retrospectively reviewed for ocular and systemic features. CRS was diagnosed either on the basis of positive serology for rubella antibodies or with the classic triad of congenital cataract, sensorineural hearing loss, and congenital heart defect. Children with photographic documentation of the face were analyzed independently by three experienced investigators for facial dysmorphic features (triangular face, microcephaly, broad forehead, low anterior hairline, whorl on the anterior hairline, prominent nose, micrognathia). The dysmorphic feature was recorded as present only when at least two of the three examiners confirmed its existence.

RESULTS

CRS was diagnosed in 237 children: mean age at presentation, 5.45 ± 4.5 years; 126 males (53%); bilateral cataract, 176 (75%). Positive serology for rubella antibodies was noted in 153 children (65%). Photographic record of facial features was documented in 127 (54%). The most common dysmorphic facial feature was wide forehead (82 [65%]), followed by low anterior hairline with whorl (41 [32%]). However, microcornea (P = 0.9801), cataract (P = 0.8342), pupillary sphincter atrophy (P = 0.7421), and salt and pepper retinopathy (P = 0.8803) were not significantly associated with the presence of facial dysmorphism. Congenital heart disease was significantly associated with facial dysmorphism (P = 0.0308). Sensorineural hearing loss was not associated with the presence of facial dysmorphism (P = 0.8463).

CONCLUSIONS

Facial dysmorphism is common in children with CRS, but it was not predictive of the presence of ocular manifestations of CRS in this cohort.

Reduction of lens size in PAX6-related aniridia

Heterozygous mutation of PAX6 in humans leads to congenital aniridia (OMIM 106210) which is typified by congenital iris and foveal defects, and later onset glaucoma, aniridic keratopathy, and cataract. Mice heterozygous for Pax6 mutations phenocopy many aspects of aniridia including the iris defects, keratopathy and cataract, although Pax6 mutant mice have small lenses, a phenotype which is not typically reported in human aniridia, perhaps due to difficulties in measuring lens diameter during typical ophthalmic examinations as the lens periphery is shielded by the iris. In order to overcome this, records of patients diagnosed with congenital aniridia between April 2015 and May 2021 at the Necker-Enfants Malades Hospital, and genetically confirmed with a disease-causing PAX6 variant, were retrospectively reviewed for those with normal axial length whose iris defects allowed visualization of the lens margins and corneal diameter to allow calculation of a lens/corneal diameter ratio. This value was compared with values obtained from a cohort of patients with Sjödell grade IV oculocutaneous albinism type 1 (OCA1; OMIM 203100) which allowed visualization of the lens periphery via iris transillumination. This analysis revealed that patients with congenital aniridia had a significantly lower lens/corneal ratio when compared to those with albinism, suggesting that humans haploinsufficient for PAX6, like mice, rats, frogs, and zebrafish, exhibit reductions in lens size.

D348N Mutation of BFSP1 Gene in Congenital Cataract: it Does Matter

Beaded filament structural protein 1 (BFSP1) gene plays important role in the development of congenital cataract. We aimed to investigate and analyze the molecular mechanism of congenital cataract caused by D348N mutation of BFSP1 gene, and to provide evidence for the intervention of congenital cataract. BFSP1 and CP49 genes were cloned, wild type and mutant expression plasmids of BFSP1 were constructed and transfected into 293T cells. The BFSP1 wild type and mutant (D348N) gene sequence (NM_001195) were constructed into pEGFP-N1 vector by the restriction site NheI/KpnI. The effect of mutation on cell proliferation and apoptosis was analyzed. There was no significant change between the expression site of BFSP1 D348N mutation and the wild type. The expression of BFSP1 protein in wild group was higher than that in mutant group. CCK8 detection showed that the proliferation ability of 293T cells in mutant group was weaker than that in BFSP1 group. The mutation led to an increase in apoptosis. BFSP1 mutation significantly decreases the expression of BFSP1 protein, weakened the ability of cell proliferation and increased apoptosis. BFSP1 D348N mutation may be closely associated with congenital cataract and is of great significance to the investigations of the mechanism and intervention of congenital cataract.

Identification of novel variants in Turkish families with non-syndromic congenital cataracts using whole-exome sequencing

PURPOSE

The present study aimed to identify the molecular etiology of non-syndromic congenital cataract (CC) using whole-exome sequencing (WES) analysis.

METHODS

In the present study, ophthalmologic results and pedigree analysis of the families of 12 patients with non-syndromic CC were evaluated. WES analysis was conducted after DNA was isolated from peripheral blood samples obtained from the patients.

RESULTS

Twelve non-syndromic probands (10 males and 2 females) with bilateral CC were included in the study. Patient age ranged between 1 and 11 months. WES analysis showed pathogenic/likely pathogenic variant in 7 (58%) of the 12 families and variant of unknown significance (VUS) in 5 (42%) of them. All the 13 different variants detected in 9 different CC-related genes were co-segregated with the disease. Autosomal dominant inheritance was found in 7 (58%) of the families and autosomal recessive inheritance was found in 5 (42%) of them.

CONCLUSION

To the best of our knowledge, the present research is one of the limited numbers of studies in the Turkish population in which genetically heterogeneous non-syndromic CC was investigated using WES analysis. Novel variants that we identified in DNMBP, LSS, and WFS1 genes, which are rarely associated with the CC phenotype, have contributed to the mutation spectrum of this disease. Identifying the relevant molecular genetic etiology allows accurate genetic counseling to be provided to the families.

Risk of visual axis opacification in infants with and without primary IOL implantation after congenital cataract surgery performed during the first 4 months of age

PURPOSE

The study evaluates the rate of postoperative formation of a pupillary membrane (PM) and posterior visual axis opacification (PVAO) in infants with and without primary IOL implantation during the first 4 months of infancy.

METHODS

Medical records for 144 eyes (101 infants) operated between 2005 and 2014 were evaluated. A posterior capsulectomy and anterior vitrectomy were performed. Primary IOL implantation was performed in 68 eyes, while 76 eyes were left aphakic. There were 16 bilateral cases in the pseudophakic group and 27 in the aphakic group. The follow-up period was 54.3 ± 21.05 months and 49.1 ± 18.60 months, respectively. Fisher's exact test was used for statistical analysis. The two-sample t-test with equal variance was used to compare surgery age, follow-up period and time intervals of complications.

RESULTS

The mean age of surgery was 2.1 ± 0.85 months in the pseudophakic and 2.2 ± 1.01 months in the aphakic group. PM was diagnosed in 40% pseudophakic and 7% aphakic eyes. A second surgery for PVAO was performed in 72% pseudophakic and 16% aphakic eyes. Both were significantly higher in the pseudophakic group. In the pseudophakic group, the number of PVAO was significantly higher in infants operated before 8 weeks of age compared to surgery age 9-16 weeks. The frequency of PM was not age-dependent.

CONCLUSION

Although it remains feasible to implant an IOL during the primary surgery, even in very young infants, there should always be solid arguments for this decision since it puts the child at higher risk of repeated surgeries under general anaesthesia.

Novel CRYGC Mutation in Conserved Ultraviolet-Protective Tryptophan (p.Trp131Arg) Is Linked to Autosomal Dominant Congenital Cataract

Congenital cataract (CC), the most prevalent cause of childhood blindness and amblyopia, necessitates prompt and precise genetic diagnosis. The objective of this study is to identify the underlying genetic cause in a Swiss patient with isolated CC. Whole exome sequencing (WES) and copy number variation (CNV) analysis were conducted for variant identification in a patient born with a total binocular CC without a family history of CC. Sanger Sequencing was used to confirm the variant and segregation analysis was used to screen the non-affected parents. The first de novo missense mutation at c.391T>C was identified in exon 3 of CRYGC on chromosome 2 causing the substitution of a highly conserved Tryptophan to an Arginine located at p.Trp131Arg. Previous studies exhibit significant changes in the tertiary structure of the crystallin family in the following variant locus, making CRYGC prone to aggregation aggravated by photodamage resulting in cataract. The variant can be classified as pathogenic according to the American College of Medical Genetics and Genomics (ACMG) criteria (PP3 + PM1 + PM2 + PS2; scoring 10 points). The identification of this novel variant expands the existing knowledge on the range of variants found in the CRYGC gene and contributes to a better comprehension of cataract heterogeneity.

Posterior Capsulotomy Size Affects the Formation of Significant Visual Axis Opacification in Congenital and Developmental Cataract

PURPOSE

To assess the relationship between posterior capsulotomy size and significant visual axis opacification (VAO) in congenital and developmental cataract.

METHODS

The charts of children aged 7 years and younger who underwent cataract surgery including primary posterior capsulotomy (PPC) and limited anterior vitrectomy between 2012 and 2022 were retrospectively reviewed. Eyes with PPC size smaller than the anterior capsulotomy size were considered as group 1. Eyes with PPC size larger than the anterior capsulotomy size were considered as group 2. Clinical characteristics, the need for Nd:YAG laser treatment or further surgery for significant VAO, and other postoperative complications were compared between the groups.

RESULTS

Sixty eyes of 41 children were included in the study. The median age at the time of surgery was 5.5 and 3 years in groups 1 and 2, respectively (P = .076). Primary intraocular lens implantation was performed in 23 (85.2%) eyes in group 1 and 25 (75.8%) eyes in group 2 (P = .364). There was no difference between the groups in terms of postoperative visual acuity (P = .983) and refractive errors (P = .154). Eight (29.6%) pseudophakic eyes received Nd:YAG laser treatment in group 1, but none of the eyes in group 2 (P = .001). Four (14.8%) eyes in group 1 and 1 (3%) eye in group 2 underwent further surgery for VAO (P = .100). The need for further intervention for significant VAO was statistically higher in group 1 (44.4% vs 3%, P < .001).

CONCLUSIONS

Larger PPC size in pediatric cataract may reduce the need for further intervention for significant VAO. [J Pediatr Ophthalmol Strabismus. 2023;60(6):441-447.].

Mutation screening in autosomal dominant congenital cataract families from North India

Congenital cataract an opacity of the eye lens is present at birth and results in visual impairment during early childhood. If left untreated, it can lead to permanent blindness. Its prevalence is ten times higher in developing countries like India. Thus, we aimed to investigate the underlying genetic defects in three autosomal dominant congenital cataract (ADCC) families from North India. Detailed family histories were collected, pedigrees drawn followed by slit-lamp examination and lens photography. Mutation screening was performed in the candidate genes for crystallins, connexins, and membrane proteins by Sanger sequencing. Pathogenicity of novel variant was assessed bioinformatically. In an ADCC (CC-3006) family with bilateral membranous cataract and microcornea, a novel change (c.1114C>T;p.P372S) in GJA3 has been detected. In other two ADCC families affected with subcapsular (CC-286) and shrunken membranous hypermature cataract (CC-3014), a nonsense mutation (c.463C>T;p.Q155X) in CRYβB2 and a frameshift deletion (c.590_591delAG;p.E197VfsX22) in CRYβA1/A3 respectively, are observed. These variants segregated completely with the phenotypes in respective families and were absent in their unaffected family members and unrelated controls (tested for novel variant in GJA3). Earlier p.Q155X (CRYβB2) and p.E197VfsX22 (CRYβA1/A3) are reported with entirely different phenotypes. Thus, findings in present study expand the mutation spectrum and phenotypic heterogeneity linked with GJA3, CRYβB2, and CRYβA1/A3 for congenital cataracts. Identifying underlying genetic defects is essential for disease management and appropriate genetic counseling.

Predictive Factors of Complications and Visual Outcomes after Pediatric Cataract Surgery: A Single Referral Center Study from Türkiye

Objectives

To evaluate the predictive factors of complications and visual acuity outcomes in pediatric cataract patients.

Materials and Methods

This retrospective, observational clinical study included 80 eyes of 50 patients treated for pediatric cataracts between 2010 and 2020. The eyes were divided into Group I (congenital cataracts, n=38) and Group II (developmental cataracts, n=42). Group II was also divided into Group IIA (aphakic, n=21) and Group IIB (pseudophakic, n=21). The effects of the age, laterality, cataract morphology, intraocular lens implantation, preoperative nystagmus/strabismus, and intraoperative anterior hyaloid rupture on complications and final best-corrected visual acuity (BCVA; logMAR) were evaluated.

Results

The median (interquartile range) age and follow-up time were 28 (5-79) months and 60 (29-84) months, respectively. There was a significant difference in mean final BCVA between Group I (0.79±0.46) and Group II (0.57±0.51) (p=0.047); however, no difference was observed between Group IIA and Group IIB (p=0.541). Having congenital cataract (p=0.045), preoperative nystagmus/strabismus (p=0.042), total/mature cataract (p<0.001), and postoperative complications (p=0.07) were significantly associated with final BCVA. However, in multivariate analysis, only total/mature cataract (β: 0.52, p<0.001) and having any complication (β: 0.24, p=0.018) were associated with final BCVA. Congenital cataract and intraoperative anterior hyaloid rupture were the only significant risk factors of postoperative complications on univariate (p=0.027 and p=0.003, respectively) and binary logistic regression analysis (odds ratio [OR]: 2.95 [95% confidence interval: 1.07-8.15], p=0.036 and OR: 4.28 [95% confidence interval: 1.55-11.77], p=0.005, respectively).

Conclusion

Total/mature cataract and the presence of any postoperative complication adversely affected the final BCVA. Having a congenital cataract and intraoperative anterior hyaloid membrane rupture increased the risk of complications.

Novel compound heterozygous variants of the SEC23A gene in a Chinese family with cranio-lenticulo-sutural dysplasia based on data from a large cohort of congenital cataract patients

BACKGROUND

Cranio-lenticulo-sutural dysplasia (CLSD) is a rare dysmorphic syndrome characterized by skeletal dysmorphism, late-closing fontanels, and cataracts. CLSD is caused by mutations in the SEC23A gene (OMIM# 607812) and can be inherited in either an autosomal dominant or autosomal recessive pattern. To date, only four mutations have been reported to cause CLSD. This study aims to identify the disease-causing variants in a large cohort of congenital cataract patients, to expand the genotypic and phenotypic spectrum of CLSD, and to confirm the association between SEC23A and autosomal recessive CLSD (ARCLSD).

METHODS

We collected detailed medical records and performed comprehensive ocular examinations and whole-exome sequencing (WES) on 115 patients with congenital cataracts. After suspecting that a patient may have CLSD based on the sequencing results, we proceeded to conduct transmission electron microscopy (TEM) on the cultured skin fibroblasts. The clinical validity of the reported gene-disease relationships for the gene and the disease was evaluated using the ClinGen gene curation framework.

RESULTS

Two novel compound heterozygous variants (c.710A > C p.Asp237Ala, c.1946T > C p.Leu649Pro) of the SEC23A gene, classified as variant of uncertain significance, were identified in the proband with skeletal, cardiac, ocular, and hearing defects. The observation of typical distended endoplasmic reticulum cisternae further supported the diagnosis of CLSD. Application of the ClinGen gene curation framework confirmed the association between SEC23A and ARCLSD.

CONCLUSION

This study expands the genotypic and phenotypic spectrum of CLSD, proposes TEM as a supplemental diagnostic method, and indicates that congenital cataracts are a typical sign of ARCLSD.

Pediatric Cataract: Disparately Blinding Globally and in the United States

Childhood cataract is a complex condition requiring longitudinal care, including early diagnosis, timely referral to a specialist, early surgical intervention, and dedicated postoperative care. Adherence to refractive correction and amblyopia therapy are critical for visual rehabilitation, even months to years after the cataract is removed. We review the impact of the social determinants of health on each step in the visual rehabilitation pathway for children with congenital and infantile cataracts. Children from socioeconomically marginalized backgrounds are more likely to experience delays in access to care and utilization of surgical services. They are also less likely to adhere to amblyopia therapy, with corresponding decrements in visual outcomes. Additional sociocultural factors, including parental stress, self-efficacy, and health literacy, pose barriers for these children. Standardizing clinical roles, improving health communication, managing parental stress, and implementing systemic policy changes may alleviate socioeconomic disparities in outcomes for children with cataracts.

Indications for Systemic and Genetic Testing in Patients with Congenital Cataracts

Congenital cataracts account for a significant proportion of blindness in children worldwide. They affect approximately 12-136 per 100,000 births worldwide. A genetic etiology is present in a large proportion of patients and can lead to isolated cataracts or those in the context of genetic multisystem disorders. We present two examples of genetically determined childhood cataracts and briefly review the work-up of such patients. Mutations in numerous genes have been identified that cause congenital cataracts, such as those encoding for crystallins, connexins and aquaporins, as well as some developmental regulatory proteins. Identifying the genetic or molecular etiology of congenital cataract is essential for identifying and better understanding the pathways leading to this disease, and for providing individualized genetic counseling and guiding treatment for possible associated systemic problems.

Managing Pediatric Cataract Patients: Amblyopia Treatment and Binocularity Outcomes

Unilateral congenital cataracts present multiple barriers in the development of vision and stereoacuity despite the improved visual optics that early surgery, contact lenses and intraocular lenses (IOL) have provided. With better understanding of the latent period (the timeframe in which the abnormal event has no long-term effect on visual development in the deprived eye) and the critical periods (the age range during which developing brains can be altered in a profound and permanent way by abnormal experience) for stereoacuity and amblyopia we can focus our treatment methods to not only improve vision but also develop binocularity. Fifty years ago, it was believed that it was almost impossible for an eye with a unilateral congenital cataract to achieve good visual acuity. Twenty-five years ago, we believed that it was almost impossible for an eye with a unilateral cataract to achieve stereoacuity. It is time to expand our belief that the best that we can do with the eye in unilateral congenital cataract is to create a spare.

MIR204 n.37C>T variant as a cause of chorioretinal dystrophy variably associated with iris coloboma, early-onset cataracts and congenital glaucoma

Four members of a three-generation Czech family with early-onset chorioretinal dystrophy were shown to be heterozygous carriers of the n.37C>T in MIR204. The identification of this previously reported pathogenic variant confirms the existence of a distinct clinical entity caused by a sequence change in MIR204. Chorioretinal dystrophy was variably associated with iris coloboma, congenital glaucoma, and premature cataracts extending the phenotypic range of the condition. In silico analysis of the n.37C>T variant revealed 713 novel targets. Additionally, four family members were shown to be affected by albinism resulting from biallelic pathogenic OCA2 variants. Haplotype analysis excluded relatedness with the original family reported to harbour the n.37C>T variant in MIR204. Identification of a second independent family confirms the existence of a distinct MIR204-associated clinical entity and suggests that the phenotype may also involve congenital glaucoma.

What we have learned from the Infant Aphakia Treatment Study: The 49th Annual Frank D. Costenbader Lecture

Unilateral congenital cataracts lead to deprivation amblyopia, which can be severe. Until the 1970s, they were believed to be always associated with poor visual outcomes. However, advances in our understanding of the plasticity of the infant brain and the development of better surgical techniques allowed good visual outcomes to be obtained in a few of these patients. The Infant Aphakia Treatment Study (IATS) was conducted to provide empirical evidence regarding the best type of optical correction to be used following surgical extraction of the cataract. Specifically, infants were randomly assigned to either be left aphakic and to wear contact lenses or an intraocular lens (IOL) was implanted and the residual refractive error was corrected with spectacles. The study found that good visual acuity and stereopsis could be achieved in some patients in both treatment groups. Early cataract surgery, consistent optical correction and part-time patching of the fellow eye are important elements needed to achieve good visual outcomes. However, excess patching of the fellow eye may interfere with the development of stereopsis. More adverse events occurred after IOL implantation, particularly visual axis opacification, compared with the infants who were left aphakic. Glaucoma-related adverse events occurred in 40% of eyes after a 10-year follow-up and were not associated with IOL implantation. Further research is needed to increase the percentage of children with unilateral congenital cataracts who achieve good visual outcomes.

Congenital cataracts affect the retinal visual cycle and mitochondrial function: A multi-omics study of GJA8 knockout rabbits

Congenital cataracts are a threat to visual development in children, and the visual impairment persists after surgical treatment; however, the mechanisms involved remain unclear. Previous clinical studies have identified the effect of congenital cataracts on retinal morphology and function. To further understand the molecular mechanisms by which congenital cataracts affect retinal development, we analyzed retina samples from 7-week-old GJA8-knockout rabbits with congenital cataracts and controls by four-dimensional label-free quantification proteomics and untargeted metabolomics. Bioinformatics analysis of proteomic data showed that retinol metabolism, oxidative phosphorylation, and fatty acid degradation pathways were downregulated in the retinas of rabbits with congenital cataracts, indicating that their visual cycle and mitochondrial function were affected. Additional validation of differentially abundant proteins related to the visual cycle and mitochondrial function was performed using Parallel reaction monitoring and western blot experiments. Untargeted metabolome analysis showed significant upregulation of the antioxidant glutathione and ascorbic acid in the retinas of rabbits with congenital cataracts, indicating that their oxidative stress balance was not dysregulated. SIGNIFICANCE: Congenital cataracts in children can alter retinal structure and function, yet the mechanisms are uncertain. Here is the first study to use proteomics and metabolomics approaches to investigate the effects of congenital cataracts on retinal development in the early postnatal period. Our findings suggest that congenital cataracts have an impact on the retinal visual cycle and mitochondrial function. These findings give insight on the molecular pathways behind congenital cataract-induced visual function impairment in the early postnatal period.

Novel compound heterozygous variant of GJA8 gene in two siblings with congenital cataract mimics an autosomal recessive trait

BACKGROUND

GJA8 gene is known to cause autosomal dominant congenital cataract. Here we report a novel compound heterozygous variant of GJA8 gene in two siblings that mimics an autosomal recessive trait.

PATIENTS AND METHODS

Two siblings from a non-consanguineous Chinese family suffered from isolated congenital cataract. Whole exome sequencing was performed to identify disease-causing variants followed by a confirmatory Sanger sequencing.

RESULTS

Whole exome sequencing revealed a novel compound heterozygous variant of GJA8 gene, c.855delG(p.Met286Trpfs*71)/c.1125delC(p.Gly376Glufs*33), in the proband. Sanger sequencing confirmed that the proband and his sister harboured this compound heterozygous variant, while the parents were heterozygous carriers, suggesting an autosomal recessive inheritance pattern. Both parents showed mildly impaired vision, but only the father had mild nuclear opacities, suggesting an autosomal dominant trait with reduced penetrance in one of the pathogenic alleles.

CONCLUSIONS

Our report shows compound heterozygous variant of GJA8 gene may mimic autosomal recessive inheritance pattern, and reminds clinicians to perform needful examination. The two novel pathogenic GJA8 variants expand the mutational spectrum of congenital cataract. This study also provides accurate genetic diagnosis for the family.

Mutational spectrum in a Chinese cohort with congenital cataracts

BACKGROUND

To identify the mutational spectrum in a Chinese cohort with congenital cataracts.

METHODS

Probands (n = 164) with congenital cataracts and their affected or unaffected available family members were recruited for clinical examinations and panel-based next-generation sequencing, then classified into a cohort for further mutational analysis.

RESULTS

After recruitment (n = 442; 228 males and 214 females), 49.32% (218/442) of subjects received a clinical diagnosis of congenital cataracts, and 56.88% (124/218) of patients received a molecular diagnosis. Eighty-four distinct variants distributed among 43 different genes, including 42 previously reported variants and 42 novel variants, were detected, and 49 gene variants were causally associated with patient phenotypes; 27.37% of variants (23/84) were commonly detected in PAX6, GJA8 and CRYGD, and the three genes covered 33.06% of cases (41/124) with molecular diagnosis. The majority of genes were classified as genes involved in nonsyndromic congenital cataracts (19/43, 44.19%) and were responsible for 56.45% of cases (70/124). The majority of functional and nucleotide changes were missense variants (53/84, 63.10%) and substitution variants (74/84, 88.10%), respectively. Nine de novo variants were identified.

CONCLUSION

This study provides a reference for individualized genetic counseling and further extends the mutational spectrum of congenital cataracts.

Surgical management of lifebuoy cataract

Lifebuoy cataract is a rare form of congenital cataract with anatomical characteristics. Herein, we present a case of an otherwise healthy 42-year-old female with a long-standing history of blurred vision. Examination showed the presence of esotropia and bilateral horizontal nystagmus. Visual acuity was limited to light perception in both eyes. Slit-lamp examination showed a calcified lens capsule with the absence of lens material in the right eye and the presence of an annular cataract in the left eye, corresponding to a unilateral lifebuoy cataract. She underwent cataract surgery with intraocular lens implantation. We report the clinical findings, anterior segment optical coherence tomography (AS-OCT), and surgical management tips. We noticed that during surgery, both anterior capsulorhexis and central membrane removal were the most challenging steps due to the absence of central nucleus and the strong adherence of central membrane to the anterior hyaloid.

Stimulus-evoked and resting-state alpha oscillations show a linked dependence on patterned visual experience for development

Persistent visual impairments after congenital blindness due to dense bilateral cataracts have been attributed to altered visual cortex development within a sensitive period. Occipital alpha (8-14 Hz) oscillations were found to be reduced after congenital cataract reversal, while participants performed visual motion tasks. However, it has been unclear whether reduced alpha oscillations were task-specific, or linked to impaired visual behavior in cataract-reversed individuals. Here, we compared resting-state and stimulus-evoked alpha activity between individuals who had been treated for dense bilateral congenital cataracts (CC, n = 13, mean duration of blindness = 11.0 years) and age-matched, normally sighted individuals (SC, n = 13). We employed the visual impulse response function, adapted from VanRullen and MacDonald (2012), to test for the characteristic alpha response to visual white noise. Participants observed white noise stimuli changing in luminance with equal power at frequencies between 0 and 30 Hz. Compared to SC individuals, CC individuals demonstrated a reduced likelihood of exhibiting an evoked alpha response. Moreover, stimulus-evoked alpha power was reduced and correlated with a corresponding reduction of resting-state alpha power in the same CC individuals. Finally, CC individuals with an above-threshold evoked alpha peak had better visual acuity than CC individual without an evoked alpha peak. Since alpha oscillations have been linked to feedback communication, we suggest that the concurrent impairment in resting-state and stimulus-evoked alpha oscillations indicates an altered interaction of top-down and bottom-up processing in the visual hierarchy, which likely contributes to incomplete behavioral recovery in individuals who experienced transient congenital blindness.

Evaluation of Genetic Testing in a Cohort of Diverse Pediatric Patients in the United States with Congenital Cataracts

The aim of this study was to evaluate the diagnostic yield from prior genetic testing in a 20-year cohort of pediatric patients with congenital cataracts. A retrospective review of patients with congenital cataracts who underwent genetic testing was completed from 2003–2022. The diagnostic yield of the test was determined by variant classification and inheritance pattern. Variants from initial testing underwent reclassification in accordance with ACMG-AMP (American College of Medical Genetics and Genomics—American Association of Molecular Pathology) 2015 or 2020 ACMG CNV guidelines. A total of 95 variants were identified in 52 patients with congenital cataracts (42 bilateral, 10 unilateral); 42 % were White, 37% were Hispanic, 8% were Black, and 6% were Asian. The majority of patients (92%) did not have a family history of congenital cataracts but did have systemic illnesses (77%). Whole exome sequencing and targeted congenital cataract panels showed diagnostic yields of 46.2% and 37.5%, respectively. Microarray had the lowest yield at 11%. Compared to the initial classification, 16% (15 of 92 variants) had discrepant reclassifications. More testing is needed, and an increased focus is warranted in the field of ocular genetics on congenital cataracts, particularly in those with systemic illnesses and no family history, to advance our knowledge of this potentially blinding condition.

[Analysis of novel compound heterozygous variants of the GJA8 gene in a child with congenital cataract]

OBJECTIVE

To explore the genetic basis for child with congenital cataract.

METHODS

The child was subjected to next-generation sequencing. Candidate variant was verified by Sanger sequencing of his family members.

RESULTS

The proband was found to harbor novel heterozygous variants of c.855del and c.872dup of the GJA8 gene, which were inherited from his father and mother, respectively. Neither of these two variants has been reported. Based on the American College of Medical Genetics and Genomics (ACMG) guidelines, the c.855del and c.872dup variants were classified as likely pathogenic (PVS1_S+PM2+PP4) and pathogenic (PVS1_S+PM2+PM3+PP4), respectively.

CONCLUSION

The c.855del and c.872dup variants of the GJA8 gene probably underlay the congenital cataract in this patient.

Anterior segment optical coherence tomography findings in the Infant Aphakia Treatment Study (IATS): a secondary analysis of a randomized clinical trial

PURPOSE

To correlate the diagnosis of glaucoma among children in the Infant Aphakia Treatment Study (IATS) by age 10 years with anterior segment optical coherence tomography (AS-OCT) findings.

METHODS

A multicenter randomized controlled trial of 114 infants with unilateral congenital cataract who were 1-6 months of age at surgery. Data on long-term glaucoma-related status and outcomes were collected when children were 10.5 years old. Participants were randomized at cataract surgery to either primary intraocular lens (IOL) or no IOL implantation (contact lens [CL]). AS-OCT findings in eyes with glaucoma were compared to eyes which did not have glaucoma and to the fellow eyes, between fellow and treated eyes, and between the IOL and CL groups.

RESULTS

There were no significant differences in the mean nasal and temporal anterior chamber angle (ACA) or mean nasal and temporal angle opening distance (AOD) for nonglaucomatous, glaucomatous, and fellow eyes (P = 0.31, 0.16, 0.43, 0.08 resp.). There were also no significant differences in mean nasal and temporal ACA and AOD between fellow and treated eyes (P = 0.44, 0.67, 0.57, 0.38 resp.), or between IOL and CL groups (P = 0.36, 0.35, 0.49, 0.44, resp.).

CONCLUSIONS

AS-OCT confirmed that eyes with glaucoma in IATS had predominantly open angles with similar ACA and AOD to eyes without glaucoma and to fellow eyes. Furthermore, congenital cataract surgery with or without an IOL did not result in a significant difference in ACA or AOD compared to fellow eyes in IATS.

Corneal Biometric Parameters and Refractive Properties in Microcornea With Normal Axial Length

PURPOSE

The purpose of this study was to evaluate the features of and relationships among corneal diameter, central corneal thickness (CCT), endothelial cell density (ECD), and corneal refractive properties in cases of microcornea (MC) with normal axial length.

METHODS

We included 22 patients (35 eyes) with MC and cataracts and 41 patients (48 eyes) with isolated cataracts as age-matched controls. They were divided into patients with MC younger than 18 years (MC-child), patients with MC 18 years or older (MC-adult), children with congenital cataracts (CCs), and adults with senile cataracts (SCs). Corneal diameter, axial and anterior chamber length, and keratometry were measured; central corneal endothelial cell imaging was performed.

RESULTS

The mean horizontal corneal diameter was 7.71 ± 1.51 and 8.78 ± 0.52 mm in MC-child and MC-adult groups, respectively, and 11.89 ± 0.59 and 11.52 ± 2.42 mm in child and adult controls, respectively. The mean CCT was 641.26 ± 63.37 (MC-child) and 617.38 ± 45.40 mm (MC-adult), and 554.92 ± 34.64 (CC) and 551.58 ± 28.47 mm (SC). The mean ECD was 2898.47 ± 443.90 (MC-child) and 2825.81 ± 484.65 cells/mm 2 (MC-adult), and 3155.13 ± 372.67 (CC) and 2749.33 ± 399.63 cells/mm 2 (SC). The average keratometry was 44.22 ± 3.14 D (MC-child) and 43.86 ± 2.59 D (MC-adult), and 44.19 ± 1.44 D (CC) and 43.94 ± 1.34 D (SC).

CONCLUSIONS

Patients with MC and normal axial length possess specific parameters, including significantly smaller corneal diameter and thicker CCT than the patients in the control groups. There were no significant differences in ECD and average keratometry. These parameters should be taken into account in the follow-up and treatment.

[Characterization of congenital cataract and postoperative visual outcome in a Pediatric Ophthalmology Unit in a middle-income country]

The functional visual outcome after cataract surgery is influenced by several factors such as the age at diagnosis and surgical treatment, as well as visual rehabilitation.

OBJECTIVE

to characterize con genital cataract patients and assess the postoperative visual outcome in an ophthalmological care center in Guatemala.

PATIENTS AND METHOD

A cross-sectional retrospective study. Clinical records of all congenital cataract patients who underwent congenital cataract surgery from 2014 and 2015 were reviewed. The following was recorded: postoperative visual acuity, age at diagnosis and surgery, sex, unilateral or bilateral involvement, etiology and morphology of the cataract, preoperative poor visual prognosis factors, and postoperative follow-up.

RESULTS

Fifty-nine patients underwent pediatric ca taract surgery in this period, ages ranging from 1 month to 13 years (median 48 months), and 23 were congenital (38.98%). Fourteen were male, 16 bilateral, and the mean age at diagnosis and surgery was 7 and 12 months, respectively. Only 13 patients completed 3 years of follow-up visits. Visual acuity was recorded at 3 years after surgery, observing in 11 patients and 8 patients visual impairment or worse, respectively. Delayed consultations occurred in 82.6% of the patients (older than 3 months of age).

CONCLUSION

In this series, the diagnosis of congenital cataract and its surgical treatment were delayed, observing a high rate of patients unable to complete follow-up visits. The visual outcome at 3 years after congenital cataract surgery was mostly visual impairment or worse.

[Ocular biometry of infants and young children with congenital cataract]

Objective: To understand the developmental characteristics of early ocular biological parameters in patients with congenital cataract. Methods: Retrospective case series study. The ocular biometry data such as the axial length, corneal curvature, anterior chamber depth and central corneal thickness of 169 patients under 3 years old who were diagnosed with congenital cataract in Eye Hospital of Wenzhou Medical University (Hangzhou Branch) from June 2016 to June 2020 were reviewed, and they were analyzed by 3 age groups. There were 87, 41, and 41 patients in three age groups, 1 to 6 months, 7 to 12 months, and 13 to 36 months, respectively; 108 patients with bilateral affected eyes and 61 patients with unilateral affected eyes were included; 84 patients with partial opacity lens and 85 patients with total opacity lens were included. The right eyes of the patients with bilateral congenital cataract were selected for analysis. Statistical analysis of ocular biological parameters between groups was performed using the independent samples t-test and paired samples t-test. Statistical analysis of the relationship between age in months and biological parameters was performed using the Pearson's correlation test. Results: The axial length at the age of 1 to 6 months in the affected eyes of patients with bilateral cataract was (17.59±1.19) mm, it was shorter than the affected eyes of patients with unilateral cataract [(18.18±1.34) mm], and the axial length in the affected eyes of patients with unilateral cataract were shorter than the healthy eyes [(19.01±0.93) mm]. At the age of 7 to 12 months, the axial length in the affected eyes of patients with unilateral cataract [(19.89±0.74) mm] was shorter than the healthy eyes [(20.48±0.43) mm]. The differences were statistically significant (t=-2.06, -5.62, -3.47, all P<0.05). The axial length in the affected eyes with partial opacity at the age of 1 to 6 months was shorter than those with total opacity [(17.43±1.14) mm vs. (18.06±1.29) mm; t=-2.38, P=0.020]. The difference in axial length (affected eyes vs. healthy eyes) was significantly correlated with the age in months in partial cataract (r=0.53, P=0.001). The corneal curvature in the affected eyes of patients with unilateral cataract was flatter than the healthy eyes at the age of 7 to 12 months [(42.41±1.82) D vs. (43.19±1.96) D; t=-2.29, P=0.038], but was steeper at the age of 13 to 36 months [(43.36±2.32) D vs. (42.55±1.88) D; t=2.17, P=0.043]. The anterior chamber depth in the affected eyes of patients with unilateral cataract was less than the healthy eyes at the age of 1 to 6 months [(2.44±0.37) mm vs. (2.58±0.33) mm; t=-2.08, P=0.048].The central corneal thickness in the affected eyes of patients with unilateral cataract was thicker than the healthy eyes both at the age of 1 to 6 months and 7 to 12 months [(555.26±46.95) μm vs. (541.85±40.78) μm, (542.93±27.63) μm vs. (530.93±30.36) μm; t=3.82, 2.26; P=0.001, 0.040]. Conclusions: Congenital cataracts maybe affect the early development of axial length, corneal curvature, anterior chamber depth and central corneal thickness. The degree of lens opacity maybe affecte the early axial length development. The axial length in eyes with partial opacity can be shorter than those with total opacity before the age of 6 months, and thereafter gradually outnumbered the latter.

Pathogenic variants in the CYP21A2 gene cause isolated autosomal dominant congenital posterior polar cataracts

BACKGROUND

Congenital cataracts are the most common cause of visual impairment worldwide. Inherited cataract is a clinically and genetically heterogeneous disease. Here we report disease-causing variants in a novel gene, CYP21A2, causing autosomal dominant posterior polar cataract. Variants in this gene are known to cause autosomal recessive congenital adrenal hyperplasia (CAH).

METHODS

Using whole-exome sequencing (WES), we have identified disease-causing sequence variants in two families of British and Irish origin, and in two isolated cases of Asian-Indian and British origin. Bioinformatics analysis confirmed these variants as rare with damaging pathogenicity scores. Segregation was tested within the families using direct Sanger sequencing.

RESULTS

A nonsense variant NM_000500.9 c.955 C > T; p.Q319* was identified in CYP21A2 in two families with posterior polar cataract and in an isolated case with unspecified congenital cataract phenotype. This is the same variant previously linked to CAH and identified as Q318* in the literature. We have also identified a rare missense variant NM_000500.9 c.770 T > C; p.M257T in an isolated case with unspecified congenital cataract phenotype.

CONCLUSION

This is the first report of separate sequence variants in CYP21A2 associated with congenital cataract. Our findings extend the genetic basis for congenital cataract and add to the phenotypic spectrum of CYP21A2 variants and particularly the CAH associated Q318* variant. CYP21A2 has a significant role in mineralo- and gluco-corticoid biosynthesis. These findings suggest that CYP21A2 may be important for extra-adrenal biosynthesis of aldosterone and cortisol in the eye lens.

A Retrospective Study on the Eye-Related Quality of Life, Functional Vision, and Their Determinants Among Children Following Congenital and Developmental Cataracts Surgery and Its Impact on Their Families Using the PedEyeQ

Objectives

To evaluate the eye-related quality of life (ER-QOL), functional vision, and their determinants in children following congenital and developmental cataract surgery, as the impact on their families, using the Pediatric Eye Questionnaire (PedEyeQ).

Materials and Methods

This was a retrospective cross-sectional study involving 107 children (aged 0–11 years) with congenital and developmental cataracts who had undergone surgery, as well as 59 visually healthy controls (aged 0–11 years). One parent for each child completed either the Proxy 0–4 PedEyeQ, the Proxy 5–11 PedEyeQ, or the Parent PedEyeQ, depending on their child's age. Mann-Whitney U and Kruskal-Wallis tests were then conducted to compare the differences between groups and to analyze their determinants.

Results

PedEyeQ scores were found to be lower in postoperative children with congenital and developmental cataracts compared with the control group across all study domains. The PedEyeQ Proxy 0 to 4 years' greatest mean difference was 27 points worse in the Functional Vision domain (95% CI −34 to −19; p &lt; 0.001). We also found that the occurrence of nystagmus (p &lt; 0.005) and strabismus (p &lt; 0.005) were the major factors affecting participants' functional vision. The PedEyeQ Proxy 5 to 11 years' greatest mean difference was 23 points worse in this same domain (95% CI −30 to −15; p &lt; 0.001), with nystagmus (p &lt; 0.05) being the main determinant herein. Parent PedEyeQ 0 to 4 years' greatest difference was 46 points worse on the Worry about their Child's Eye Condition domain (95% CI −57 to −36; p &lt; 0.001). Similarly, parents of children with ophthalmologic abnormalities, including nystagmus (p &lt; 0.001) and strabismus (p &lt; 0.05), were significantly more worried about their children's eye condition. Parent PedEyeQ 5 to 11 years' greatest difference was also found to be 30 points worse on the Worry about their Child's Eye Condition domain (95% CI −43 to −17; p &lt; 0.005).

Conclusions

Children who have undergone congenital and developmental cataract surgery experience a lower quality of life and reduced functional vision. Their families are also significantly and adversely affected herein. Thus, more attention is needed on these groups, with more focused measures being administered to both children and their families.

Novel Homozygous Missense Variant in GJA3 Connexin Domain Causing Congenital Nuclear and Cortical Cataracts

Congenital cataracts (CC) are responsible for approximately one-tenth of childhood blindness cases globally. Here, we report an African American family with a recessively inherited form of CC. The proband demonstrated decreased visual acuity and bilateral cataracts, with nuclear and cortical cataracts in the right and left eye, respectively. Exome sequencing revealed a novel homozygous variant (c.563A > G; p.(Asn188Ser)) in GJA3, which was predicted to be pathogenic by structural analysis. Dominantly inherited variants in GJA3 are known to cause numerous types of cataracts in various populations. Our study represents the second case of recessive GJA3 allele, and the first report in African Americans. These results validate GJA3 as a bona fide gene for recessively inherited CC in humans.

Mapping of global research output in congenital cataracts from 1903 to 2021

BACKGROUND AND AIM

Globally, congenital cataract remains one of the main causes of visual loss in children. This study was designed to plot the overall research output and evaluate some key bibliometric indicators in congenital cataracts research.

METHODS

Publications on congenital cataracts were retrieved from the Web of Science Core Collection database. The published literature was searched using the keywords "congenital cataract" OR "congenital cataracts" in the title filed with document types and language restrictions. The data were exported into HistCite to analyze; publication year, top authors, countries, institutions, journals, keywords, and most cited studies. VOSviewer software was used to construct network visualization mapping.

RESULTS

A total of 1427 publications (1903-2021) published in English language were included in this study. Over the past few decades, the total number of publications in congenital cataracts was found to be increased. The most productive year was 2016 (n = 72), while the most cited year was 1941 (1268 citations). The Investigative Ophthalmology & Visual Science (Impact Factor: 4.799) was the most attractive journal with 161 publications, and the Molecular Vision (Impact Factor : 2.367) was the most cited journal with 1915 citations and 161.723 citations per year. The most productive country was the United States of America (USA) (n = 325), while the most active institute was Sun Yat-sen University, China (n = 36). The most prolific author was Yao K (n = 27). The most studied Web of Science category was ophthalmology (n = 852). The most widely used keyword was congenital (n = 1427). The most cited paper in congenital cataracts was "Congenital cataract following German measles in the mother, cited 1268 times. The USA and author keyword congenital cataract had the highest total link strength.

CONCLUSION

These findings provide useful insights, current status, and trends in clinical research in congenital cataracts. This study can be used to identify future research areas and standard bibliography references for better diagnosis and disease control.

Fine Breakpoint Mapping by Genome Sequencing Reveals the First Large X Inversion Disrupting the NHS Gene in a Patient with Syndromic Cataracts

Inversions are structural variants that are generally balanced. However, they could lead to gene disruptions or have positional effects leading to diseases. Mutations in the NHS gene cause Nance-Horan syndrome, an X-linked disorder characterised by congenital cataracts and dental anomalies. Here, we aimed to characterise a balanced pericentric inversion X(p22q27), maternally inherited, in a child with syndromic bilateral cataracts by breakpoint mapping using whole-genome sequencing (WGS). 30× Illumina paired-end WGS was performed in the proband, and breakpoints were confirmed by Sanger sequencing. EdU assays and FISH analysis were used to assess skewed X-inactivation patterns. RNA expression of involved genes in the breakpoint boundaries was evaluated by droplet-digital PCR. We defined the breakpoint position of the inversion at Xp22.13, with a 15 bp deletion, disrupting the unusually large intron 1 of the canonical NHS isoform, and also perturbing topologically-associated domains (TADs). Moreover, a microhomology region of 5 bp was found on both sides. RNA analysis confirmed null and reduced NHS expression in the proband and his unaffected mother, respectively. In conclusion, we report the first chromosomal inversion disrupting NHS, fine-mapped by WGS. Our data expand the clinical spectrum and the pathogenic mechanisms underlying the NHS defects.