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.

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.

Variant in EZR leads to defects in lens development

BACKGROUND

Congenital cataract is a common cause of blindness. Genetic factors always play important role.

MATERIAL AND METHODS

This study identified a novel missense variant (c.1412C>T (p.P471L)) in the EZR gene in a four-generation Chinese family with nuclear cataract by linkage analysis and whole-exome sequencing. A knockout study in zebrafish using transcription activator-like effector nucleases was carried out to gain insight into candidate gene function.

RESULTS

Conservative and functional prediction suggests that the P-to-L substitution may impair the function of the human ezrin protein. Histology showed developmental delays in the ezrin-mutated zebrafish, manifesting as multilayered lens epithelial cells. Immunohistochemistry revealed abnormal proliferation patterns in mutant fish.

CONCLUSIONS

The study suggests that ezrin may be involved in the enucleation and differentiation of lens epithelial cells.

Refractive index adjustable intraocular lens design to achieve diopter control for improving the treatment of ametropia after cataract surgery

Intraocular lens (IOL) implantation is currently the most effective clinical treatment for cataracts. Nevertheless, due to the growth of the eye axis in patients with congenital cataracts during the process of growth and development, the progressive incapacity of an IOL with a fixed focus does not meet the demands of practical usage, leading to the occurrence of ametropia. This work describes an innovative class of an IOL bulk material that offers good biosafety and light-controlled refractive index adjustment. Acrylate materials were synthesized for the preparation of IOLs by free radical polymerization of ethylene glycol phenyl ether methacrylate (EGPEMA), hydrophilic monomer 2-(2-ethoxyethoxy) ethyl acrylate (EA), and functional monomer hydroxymethyl coumarin methacrylate (CMA). Under 365/254 nm ultraviolet (UV) irradiation, the coumarin group could adjust the polymer material's refractive index through reversible photoinduced dimerization/depolymerization. Meanwhile, the potential for the IOL use is enabled by its satisfactory biosafety. Such a light-induced diopter adjustable IOL will be more appropriate for implantation during cataract surgery since it will not require the correction needed for ametropia and will offer more accurate and humane treatment. STATEMENT OF SIGNIFICANCE.

Two siblings with PEX11B-related peroxisome biogenesis disorder

The PEX11β gene contains four exons and encodes peroxisomal membrane protein 11β, which is involved in peroxisome proliferation and division. Pathogenic variants in this gene result in a rare genetic disorder with autosomal recessive inheritance called peroxisome biogenesis disorder 14B (MIM: 614920). Here, we report two affected siblings with a novel variant (NM_003846: c.11G > A, p. Trp4Ter) in the PEX11β gene that was identified by whole exome sequencing and confirmed by Sanger sequencing. The proband is a 22-year-old Iranian female who was born to consanguineous parents. The homozygous variant (NM_003846: c.11G > A, p. Trp4Ter) in the PEX11β gene was identified in the proband, who presented with cataracts, strabismus, nystagmus, intellectual disability, developmental delay, speech disorders, dry skin, and behavioral problems. Her younger affected brother, who had the same homozygous variant, suffered from similar but slightly milder symptoms. This paper reports the seventh family in the world with novel pathogenic variants in the PEX11β gene as the cause of peroxisome biogenesis disorder 14B. Additionally, the phenotypes of the previously reported patients are reviewed. Some of the phenotypes, such as bilateral congenital cataracts and intellectual disability, were present in all patients. However, other observed symptoms in previous cases, such as abnormal gait, myopia, abnormal muscle strength, hearing loss, gastrointestinal problems, skeletal disorders, and seizures, were not observed in the patients of this study. Further studies on this disorder could be valuable in determining the precise phenotype characteristics of this disease.

Risk Factors for Glaucoma Diagnosis and Surgical Intervention following Pediatric Cataract Surgery in the IRIS® Registry

PURPOSE

To compare demographic and clinical factors associated with glaucoma following cataract surgery (GFCS) and glaucoma surgery rates between infants, toddlers, and older children using a large, ophthalmic registry.

DESIGN

Retrospective cohort study.

PARTICIPANTS

Patients in the IRIS® Registry (Intelligent Research in Sight) who underwent cataract surgery at ≤ 17 years old and between January 1, 2013 and December 31, 2020.

METHODS

Glaucoma diagnosis and procedural codes were extracted from the electronic health records of practices participating in the IRIS Registry. Children with glaucoma diagnosis or surgery before cataract removal were excluded. The Kaplan-Meier estimator was used to determine the cumulative probability of GFCS diagnosis and glaucoma surgery after cataract surgery. Multivariable Cox regression was used to identify factors associated with GFCS and glaucoma surgery.

MAIN OUTCOME MEASURES

Cumulative probability of glaucoma diagnosis and surgical intervention within 5 years after cataract surgery.

RESULTS

The study included 6658 children (median age, 10.0 years; 46.2% female). The 5-year cumulative probability of GFCS was 7.1% (95% confidence interval [CI], 6.1%-8.1%) and glaucoma surgery was 2.6% (95% CI, 1.9%-3.2%). The 5-year cumulative probability of GFCS for children aged < 1 year was 22.3% (95% CI, 15.7%-28.4%). Risk factors for GFCS included aphakia (hazard ratio [HR], 2.63; 95% CI, 1.96-3.57), unilateral cataract (HR, 1.48; 95% CI, 1.12-1.96), and Black race (HR, 1.61; 95% CI, 1.12-2.32). The most common surgery was glaucoma drainage device insertion (32.6%), followed by angle surgery (23.3%), cyclophotocoagulation (15.1%), and trabeculectomy (5.8%).

CONCLUSIONS

Glaucoma following cataract surgery diagnosis in children in the IRIS Registry was associated with young age, aphakia, unilateral cataract, and Black race. Glaucoma drainage device surgery was the preferred surgical treatment, consistent with the World Glaucoma Association 2013 consensus recommendations for GFCS management.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Cataract-causing mutations S78F and S78P of γD-crystallin decrease protein conformational stability and drive aggregation

Congenital cataract is the leading cause of childhood blindness, which primarily results from genetic factors. γD-crystallin is the most abundant γ-crystallin and is essential for maintaining lens transparency and refractivity. Numerous mutations in γD-crystallin have been reported with unclear pathogenic mechanism. Two different cataract-causing mutations Ser78Phe and Ser78Pro in γD-crystallin were previously identified at the same conserved Ser78 residue. In this work, firstly, we purified the mutants and characterized for the structural change using fluorescence spectroscopy, circular dichroism (CD) spectroscopy, and size-exclusion chromatography (SEC). Both mutants were prone to form insoluble precipitates when expressed in Escherichia coli strain BL21 (DE3) cells. Compared with wild-type (WT), both mutations caused structural disruption, increased hydrophobic exposure, decreased solubility, and reduced thermal stability. Next, we investigated the aggregation of the mutants at the cellular level. Overexpression the mutants in HLE-B3 and HEK 293T cells could induce aggresome formations. The environmental stresses (including heat, ultraviolet irradiation and oxidative stress) promoted the formation of aggregates. Moreover, the intracellular S78F and S78P aggregates could be reversed by lanosterol. Molecular dynamic simulation indicated that both mutations disrupted the structural integrity of Greek-key motif 2. Hence, our results reveal the vital role of conserved Ser78 in maintaining the structural stability, which can offer new insights into the mechanism of cataract formation.

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.

Cytokines in aqueous humor of patients with congenital cataract during delayed sequential bilateral cataract surgery

BACKGROUND

To explore the changes of cytokines expression in aqueous humor (AH) of eyes of patients with congenital cataract (CC) who underwent delayed sequential bilateral cataract surgery (DSBCS).

METHODS

28 patients with CC underwent DSBCS. AH samples were collected from each eye before surgery. The contents of cytokines in AH were detected by Luminex xMAP Technology.

RESULTS

There was no significant difference in the expression of IL-8, IP-10, MCP-1 and PDGFAA in the AH of the first and second eyes (P = 0.35, 0.39, 0.17, respectively). The level of IL-8 in the first-eye AH was negatively correlated with age (ρ=- 0.519, P = 0.008). IP-10 and MCP-1 in the second-eye AH were negatively correlated with age (ρ=- 0.483, P = 0.009; ρ=- 0.445, P = 0.018,respectively).

CONCLUSION

The first-eye surgery in patients with CC may not cause the change of cytokines in the contralateral eye. The expression of IL-8, IP-10 and MCP-1 in the AH was negatively correlated with the age of patients.

TRIAL REGISTRATION

The study was registered at www.chictr.org.cn on March 22, 2022 and the clinical trial number is ChiCTR2200057927.

Examination under anesthesia: Preferred Practice

Pediatric ocular examinations are often a challenge in the outpatient setting due to limited cooperation of the child. Hence an evaluation under anesthesia (EUA) or sedation is important for a holistic ophthalmic examination. It can be combined with short procedures, such as suture removal and corneal scrappings, both for diagnosis and for the management of several ophthalmic disorders. It can also be performed before planning a surgical intervention to record the baseline characters and formulate or refine a surgical plan. Every EUA must be used as a chance to perform a complete ophthalmic examination rather than perform a single task such as recording the intraocular pressure. This article aims to provide a protocol that can be followed for a complete EUA.

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.

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.

Soft contact lens options in the management of pediatric aphakia - A quantitative and qualitative assessment

BACKGROUND

The main contact lens for pediatric aphakia has historically been a silicone elastomer lens (Silsoft SuperPlus). Due to supply chain disruption, many aphakic children required an alternative lens. We performed quantitative and qualitative comparisons between Silsoft SuperPlus and alternative aphakic soft contacts.

METHOD

Sixty-nine aphakic eyes of 49 patients wearing Silsoft SuperPlus lenses underwent the refitting process into an alternative soft contact. Data collected included lens parameters, visual acuity, keratometry, horizontal visible iris diameter, and over-refraction. A 6-question survey assessing the patients'/guardians' experience with Silsoft SuperPlus versus the alternative lens was conducted at initial fit and 1-3 months post-fit.

RESULTS

Twenty-four patients (49 %), 4(8 %), and 1(2 %) were refit into Flexlens Definitive 74, Biofinity XR, and Intelliwave Pro Toric lenses, respectively. Sixteen patients (34 %) remained in Silsoft SuperPlus due to personal lens surplus or inability to handle the new lens while 2(4 %) opted for glasses. Silsoft SuperPlus was typically successful in eyes with average keratometry (AveK) 7.4-7.6 mm. Flexlens Definitive 74 required a base curve 0.4 mm steeper than the AveK. Patients'/guardias' reported a trend toward greater comfort with handling Silsoft SuperPlus, however, patients experienced less adverse side effects with the alternative soft contact lenses.

CONCLUSIONS

Flexlens Definitive 74 was an adequate alternative to Silsoft SuperPlus in aphakic children, however lens parameters must be steepened. Keratometry streamlined the contact lens fitting process. Alternative soft lenses are a cost-effective alternative to Silsoft contact lenses.

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.

A Novel CRYBB2 Silent Variant in Autosomal Dominant Congenital Cataracts (ADCC) in Pakistani families

Objective

Congenital Cataract is a type of ophthalmic genetic disorder that appears at birth or in early childhood. Among 30 genes, CRYBB2 is one of the most common and a water-soluble protein of lens's that code for the βB2-crystallin. This study aimed to investigate the novel silent mutation in CRYBB2 of exon six in the Pakistani families of Autosomal Dominant Congenital Cataracts (ADCC).

Methods

It is a family-based study that presents three to five-generations of two Pakistani families. Data and blood samples from the families were collected from January to August 2019 from LRBT (Layton Rahmatullah Benevolent Trust) Hospital, Mansehra, Pakistan. We only included patients >15 years old. Before enrollment in the current study, each patient obtained a thorough optical examination. Samples were moved to the molecular lab using the collection and storage method. The phenol-chloroform technique was used to extract the DNA. The technique of Sanger sequencing was used to find any potential mutation in some of the selected families. Statistical and bioinformatics analysis were carried out.

Results

By using bioinformatics tools, the novel silent mutation was identified. Heterozygous silent mutation of CRYBB2 of exon 6 (c. 495G>A) was detected by the alignment of sequences. Computational prediction program did not predict the silent mutation.

Conclusion

This study investigated a novel important sequence variant in the beta-crystalline protein that causes autosomal dominant congenital cataract (ADCC) in Pakistani families. Thus, our study enlarges the CRYBB2 mutation spectrum and associated phenotypes to help clinical diagnosis of human genetic diseases.

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.

Elevated tissue transglutaminase levels in aqueous humor of congenital cataractous eyes with long axial length

Objective

To investigate the distribution of axial length (AL) and posterior staphyloma (PS) in congenital cataract (CC) patients. The correlation between AL and the concentration of tissue transglutaminase (TGM2) in the aqueous humor (AH) of cataractous eyes was also evaluated.

Methods

Cross-sectional data were collected from 499 children with CC who underwent phacoemulsification, anterior vitrectomy, and IOL implantation. AL measured by IOLMaster or A-scan ultrasonography and the presence of PS examined by B-scan ultrasonography were recorded. TGM2 levels in AH of 15 CC patients with normal axial length (NAL) and 15 CC patients with PS or long axial length (LAL) were measured by enzyme-linked immunosorbent assay.

Results

The presence of PS in congenital cataractous eyes was 11.02%, and the presence of PS + LAL in congenital cataractous eyes was 29.06%. The AH levels of TGM2 in the cataractous group with NAL were lower than those in the cataractous group with PS or LAL (P < 0.001). The concentration of TGM2 in AH were positively correlated with AL of the patients' eyes (P = 0.001). Additionally, we found that TGM2 expressed in the cytoplasm of lens epithelial cells of cataractous eyes, and the expression level increased with the AL value.

Conclusions

This study begins to lay the groundwork for investigating the characteristics of PS and LAL in patients with CC. Furthermore, AL was positively correlated with AH levels of TGM2.

Secondary Intraocular Lens Implantation (IOL) in Children- What, Why, When, and How?

PURPOSE

To provide a comprehensive review on secondary IOL implantation in children who have undergone primary surgery at an early age and are aphakic aiming at answering common dilemmas among pediatric ophthalmologists.

METHOD OF LITERATURE REVIEW

A systematic literature search was done using keywords like secondary intraocular implantation, congenital cataractand surgical aphakia. Various novel case reports, retrospective case studies and review articles covering different aspects of secondary IOL implantation were searched and reviewed using PubMed and Google scholar journal search engines.

RESULTS

This article highlights various aspects of secondary IOL implantation like the appropriate timing should be when the child is entering preschool, with the proper technique being in bag fixation is the most preferred method with least associated complications and the IOL type should be decided based on the fixation site.

CONCLUSION

Secondary IOL implantation can accomplish good and stable long-term outcomes in children. It is the most accepted mode of optical correction once the appropriate age is achieved.

Novel cataract-causing variant c.177dupC in c-MAF regulates the expression of crystallin genes for cell apoptosis via a mitochondria-dependent pathway

Congenital cataract (CC) is regarded as the most common hereditary ophthalmic disease in children. Mutations in CC-associated genes play important roles in CC formation, which provides the basis for molecular diagnosis and therapy. Among these CC-associated genes, v-maf avian musculoaponeurotic fibrosarcoma oncogene homolog (c-MAF) is considered an important transcription factor for eye and lens development. In this study, we recruited a three-generation Chinese Han family with CC. Gene sequencing revealed a novel duplication mutation in c-MAF (NM_005360.5: c.177dup) that caused frameshifting at residue 60 (p. M60fs) of c-MAF. Additionally, in the patient blood samples, the expression levels of related crystallin and noncrystallin genes confirmed that this novel duplication variant impaired the transactivation of c-MAF. Further functional analyses suggested that the c-MAF mutant induces the transcriptional inhibition of CRYAA and CRYGA and subsequently influences ME and G6PD expression levels, ultimately resulting in ROS generation and further leading to cell apoptosis via mitochondria-dependent pathways. In conclusion, we report a novel c-MAF heterozygous mutation that plays a vital role in CC formation in a Chinese family, broadening the genetic spectrum of CC.

Congenital Aniridia and Ocular motility

PURPOSE

To study the frequency and types of strabismus in congenital aniridia, the presence of associated nystagmus, foveal hypoplasia, and congenital cataracts.

DESIGN

Prospective, single-center cohort study.

METHODS

A review was conducted of 379 medical records of congenital aniridia patients who had a follow-up at the Necker-Enfants malades University Hospital between 2006 and 2022; the target age was between 12 months and 30 years. Ophthalmologic and orthoptic assessments according to age were performed. Strabismus was further analyzed according to the type of aniridia, foveal hypoplasia, and laterality of congenital cataract.

RESULTS

Strabismus was diagnosed in 150 patients; 73 were included in the study (28 males [38%] and 45 females [62%]), with a mean age of 11.02 years. The mean follow-up was 24 months. Thirty-six (49.3%) presented with familial aniridia, and 37 (50.7%) presented with sporadic aniridia. Thirty-six (49.3%) were diagnosed with esotropia, 37 (50.7%) had exotropia. Nystagmus was detected in 70 patients (96%). Thirty-nine (53.4%) suffered from congenital cataract, 10 unilateral (25.7%) and 29 bilateral (74.3%). Foveal hypoplasia was found in 73 cases (100%); esotropia was predominant in all grades. PAX6 mutation was found in 56 patients (77%).

CONCLUSION

Strabismus is one of the clinical signs of congenital aniridia. The laterality of congenital cataracts seems to affect the type of strabismus. The grade of foveal hypoplasia has little impact on strabismus but is prevalent for nystagmus. Foveal hypoplasia affects optical focus, which is essential for binocularity; this could explain the poor binocular adjustment leading to strabismus without exotropia or esotropia predominance.

Identification of a Missense Mutation in GJA8 Gene in an Iranian Family with Autosomal Dominant Congenital Cataract

Purpose

To identify the causative mutations of autosomal dominant (AD) congenital cataracts in a large Iranian family.

Methods

The complete and accurate family history and clinical information of participants were collected. A total of 51 family members, including 22 affected and 29 unaffected individuals, were recruited in this study. We performed whole exome sequencing to reveal pathogenic mutation. We used amplification refractory mutation system polymerase chain reaction and Sanger sequencing techniques to confirm segregation in patients and also to rule it out in the healthy participants.

Results

A known missense mutation, c.827C>T (S276F), in GJA8 was identified. This mutation was confirmed in all patients. Neither all healthy family members nor 100 healthy individuals who served as controls from general population had this mutation.

Conclusion

The missense mutation c. 827C>T in the GJA8 gene is associated with AD congenital lamellar cataract with complete penetrance in a six-generation Iranian family.

Integrative Bioinformatics Analysis of mRNA Expression Profiles of Mice to Explore the Key Genes Involved in Crim1 Mutation-Induced Congenital Cataracts

Crim1 has been implicated in cataracts in mice and is of great importance in the development of the eye in both humans and mice. Therefore, we aimed to clarify how Crim1 mutations affect lens development and the molecular mechanism of cataracts in mice through comprehensive bioinformatics analysis. The microarray chip was downloaded from the GEO database to obtain the gene expression profile data set. Differentially expressed genes (DEGs) were screened using the limma package. GO and KEGG analyses of DEGs were performed using the DAVID database. Then, we established the protein-protein interaction (PPI) network in Cytoscape. Next, we used MCODE to analyze the data. We obtained 750 DEGs in total, including 407 upregulated DEGs and 343 downregulated DEGs. GO analysis showed that the DEGs were mainly related to biological processes, such as apoptosis, cell translation and the immune system. KEGG analysis showed that the enriched functions and pathways were related to the processing and presentation of ribosomes, lysosomes, and antigens. We identified 18 HUB genes, among which four core genes, C1qa, C1qb, C1qc, and Cd74, were closely related to congenital cataracts induced by Crim1 mutation. This study reveals the molecular pathogenesis of congenital cataracts induced by Crim1, and this information is expected to facilitate clinical genetic testing, molecular diagnosis, prognosis, and individualized chemotherapy for congenital cataracts (CC).

Long-term Results of Congenital Cataract Surgery with Primary Intraocular Lens Implantation: A Case-Control Study of Three Age Groups

Purpose

To analyze the results of ocular refraction at the age of 7 years in children after congenital cataract surgery with intraocular lens (IOL) implantation.

Methods

A study of ocular biometric data of 143 eyes who underwent lens aspiration with IOL implantation in unilateral (23 eyes) and bilateral (60 eyes) congenital cataracts was performed. All children were divided into groups according to the age categories at the time of surgery: Group A (0-12 months) - 43 eyes; Group B (12-36 months) - 45 eyes; and Group C (older than 36 months) - 55 eyes. An empirical reduction of the implanted IOL power was performed: an undercorrection of 20% in children aged 0 to 36 months and 10% less in children aged 36 to 60 months.

Results

By age 7 years, the mean elongation ± standard deviation (SD) in Group A was 3.93 ± 1.64 mm, 2.13 ± 0.94 mm in Group B, and 0.95 ± 0.76 mm in Group C (18.7%, 9.5%, and 4.1% of the baseline axial length, respectively). There was no significant difference in axial elongation between unilateral and bilateral congenital cataracts (P = 0.32). The mean absolute refraction error (MAE) at last examination was 3.99 ± 2.12 diopter (D), 2.46 ± 1.48 D, and 1.59 ± 1.31 D in Groups A, B, and C, respectively. In infants younger than 7 months of age, by age 7 years, the mean elongation ± SD was 3.27 ± 2.86 mm (25.5%) and MAE was 3.44 ± 2.1 D. The prevalence of preoperative corneal astigmatism of 1.0 D or more was 48.95%, 2.0 D or more was 27.27%, and 3.0 D or more was 5.6%. There was no significant difference in preoperative corneal astigmatism between unilateral (1.62 ± 0.77 D) and bilateral (1.78 ± 0.90 D) congenital cataracts (P = 0.56, 95% confidence interval = -0.50-0.28). Best-corrected visual acuity (BCVA) more than 20/40 was in 53.49%, 55.55%, and 74.54% in Groups A, B, and C, respectively.

Conclusions

Although IOL power was calculated in accordance with children's age, at the age of 7 years, there was a different degree of ametropia because of the biometric changes of the growing eye, and a higher rate of ametropia was observed more in the younger age group than in the elder age groups.

A novel cataract-causing mutation Ile82Met of γA crystallin trends to aggregate with unfolding intermediate

Cataract is the most common pathogenic ophthalmic disease leading to blindness in children worldwide. Genetic disorder is the leading cause of congenital cataract, among which crystallin mutations have a high incidence. There are few reports on γA-crystallin, one critical member of crystallin superfamilies. In this study, we identified a novel pathogenic mutation (Ile82Met) in γA-crystallin from a three-generation Chinese family with cataract, and investigated the potential molecular mechanism in detail. To elucidate the pathogenic mechanism of I82M mutant, spectroscopic and solubility experiments were performed to determine the difference between the purified γA-crystallin wild type (WT) and I82M mutant under both physiological conditions and environmental stresses (UV irradiation, thermal denaturation or chemical denaturation). The I82M mutant did not affect the secondary/tertiary structure of monomeric γA-crystallin under physiological status, but decreased protein stability and increased aggregatory potency under the stressful treatment. Surprisingly, the chemical denaturation caused I82M to switch from the two-state unfolding of γA-crystallin to three-state unfolding involving an unfolding intermediate. This study expands the genetic variation map of cataract, and provides novel insights into the pathomechanism, in particular, filling in a gap in the understanding of γA-crystallin mutants causing cataract.

Angle closure secondary to lens remnants in a patient with presumed aphakia: case report

Background

Eyes with a short axial length or anterior chamber depth often develop narrowed anterior chamber angles in association with an enlarging crystalline lens. We report a case of a patient who presented in angle closure, with a distant history of prior intervention for congenital cataracts and was presumed to be aphakic.

Case presentation

A 78-year-old male presented with acute onset unilateral eye pain and blurred vision. He was found to have increased intraocular pressure, anteriorly bowed iris, and angle closure. Despite prior documentation of aphakia after treatment for congenital cataracts, detailed workup revealed residual crystalline lens material pushing the peripheral iris anteriorly. Further history confirmed that the patient underwent a procedure in the 1940’s to remove lens material centrally but was not truly aphakic. The patient was treated with anterior chamber paracentesis and intraocular pressure lowering drops. His intraocular pressure remains controlled with medical therapy alone.

Conclusions

Patients that appear to be aphakic centrally may still present with angle closure secondary to residual peripheral lens material. This case highlights the importance of keeping this etiology on the differential in a patient with presumed aphakia.

Increased Incidence of Mental Disorders in Children with Cataract: Findings from a Population-based Study

PURPOSE

To examine the incidence of mental disorders in children with cataract compared with children without cataract.

DESIGN

Nationwide cohort study based on entries in comprehensive national databases.

METHODS

The incidence of mental disorders in children born between 2000 and 2017 diagnosed with cataract before 10 years of age (n = 485) was compared with sex- and age-matched controls (n = 4358). Analyses were corrected to somatic disease in the child and parental socioeconomic status and psychiatric morbidity. The study was conducted as 2 university hospitals in Denmark managing children 6 years of age our younger with cataract.

RESULTS

The incidence of mental disorders was nearly doubled in children with cataract compared with controls (odds ratio [OR], 1.83; 95% CI, 1.28-3.63). The risk of anxiety disorders was quadrupled (OR, 4.10; 95% CI, 1.90-8.84) and the risk of developmental delay was doubled (OR, 2.66; 95% CI, 1.45-4.90). The risk of mental disorders was significantly higher in children diagnosed with cataract in the first 3 years of life compared with controls (OR, 2.36; 95% CI, 1.53-3.64), whereas those diagnosed with cataract later in childhood did not have an increased risk (OR, 1.24; 95% CI, 0.66-2.30).

CONCLUSIONS

The risk of mental disorders, in particular anxiety and neurodevelopmental delay, is markedly increased in children with cataract and even more so in those diagnosed within the first 3 years of life. Psychiatric screening instruments may be integrated in the management of these children.

A case of Dent disease type 2 with large deletion of OCRL diagnosed after close examination of a school urinary test

A 7-year-old boy visited our hospital for a detailed examination of proteinuria identified in a school urinary test. He had short stature, misaligned teeth, and mild intellectual disability. A urinary examination identified mild proteinuria and extremely high levels of beta-2 microglobulin. On blood examination, his protein, albumin, and creatinine levels were found to be normal; however, his lactate dehydrogenase and creatinine phosphokinase levels were slightly elevated. Upon histological examination, no abnormalities in glomeruli or tubules were found. Considering these results, we diagnosed our patient with Dent disease type 2 (DD2). Although the whole exome sequencing revealed large deletion of OCRL, which was seen only in Lowe syndrome and not in DD2 previously, our final diagnosis for the patient is DD2. A phenotypic continuum exists between Dent disease and Lowe syndrome, and several factors modify the phenotypes caused by defects in OCRL. Although patients have thus far been diagnosed with DD2 or Lowe syndrome on the basis of their symptoms, accumulation and analysis of cases with OCRL defects may hereafter enable more accurate diagnoses.

Congenital cataract-causing mutation βB1-L116P is prone to amyloid fibrils aggregation and protease degradation with low structural stability

Congenital cataract, a common disease with lens opacification, causes blindness in the newborn worldwide and is mainly caused by abnormal aggregation of crystallin. As the main structural protein in the mammalian lens, βB1-crystallin has an important role in the maintenance of lens transparency. Recently, the L116P mutation in βB1-CRY was found in a Chinese family with congenital nuclear cataracts, while its underlying pathogenic mechanism remains unclear. In the current study, the βB1 wild-type protein was purified, and the mutated form, βB1-L116P, was examined for examining the effect on structural stability and susceptibility against environmental stresses. Our results reveal low solubility and structural stability of βB1-L116P at physiological temperature, which markedly impaired the protein structure and the oligomerization of βB1-crystallin. Under guanidine hydrochloride-induced denaturing conditions, βB1-L116P mutation perturbed the protein unfolding process, making it prone to amyloid fibrils aggregation. More importantly, the L116P mutation increased susceptibility of βB1-crystallin against UV radiation. βB1-L116P overexpression led to the formation of more serious intracellular aggresomes under UV radiation or oxidative stress. Furthermore, the βB1-L116P mutation increased the sensitivity to the proteolysis process. These results indicate that the low structural stability, susceptibility to amyloid fibrils aggregation, and protease degradation of βB1-L116P may contribute to cataract development and associated symptoms.

Cataract-causing mutation R48C increases γA-crystallin susceptibility to oxidative stress and ultraviolet radiation

Among all congenital cataracts caused by genetic mutations, approximately half are caused by a mutation in crystallin genes, and accounts the leading cause of blindness in children globally. In this study, we investigated the underlying molecular mechanism of R48C mutation (c.142C > T; p.[Arg48Cys]) of γA-crystallin in a Mexican-Mestizo descent family causing congenital cataracts. We purified γA-crystallin wild-type (WT) and R48C mutant and compared their structural characteristics and biophysical properties by Spectroscopic experiments and environmental stress (oxidative stress, ultraviolet irradiation, pH disorders, thermal shock, or chemical denaturation). The R48C mutant did not affect the secondary and tertiary structure of monomer γA-crystallin, nor did it affect its stability to heat shock and chemicals. However, the R48C mutant destroys the oxidative stability of γA-crystallin, which makes the protein more prone to aggregation and precipitation under oxidative conditions. These might be the pathogenesis of γA-crystallin R48C mutant related to congenital cataract and help to develop anti-cataract strategies from the perspective of γA-crystallin.

Pseudo-hyaloidal Stalk in Anterior Persistent Fetal Vasculature: A Report of Two Cases

Persistent fetal vasculature (PFV) syndrome is characterized by abnormal regression of the fetal hyaloid system and may occur in various forms. In this report, two atypical cases associated with posterior capsular defect and ectopic lens material located along Cloquet’s canal are discussed. Ultrasonography of these patients presenting with bilateral total cataracts revealed a hyaloidal stalk extending from the optic nerve head to the retrolental area. During lensectomy, it was observed that lens particles were moving anteriorly from the central mid-vitreous to the aspiration port and that the posterior capsule was developmentally defective. There was no pathological vascular remnant, rather the lens material partially filled Cloquet’s canal through the opening in the posterior capsule and created a pseudo-stalk appearance on the preoperative ultrasonography. We aim to discuss possible mechanisms underlying these cases, which may help to improve our understanding of the PFV spectrum.

Study on the enlargement index of femtosecond laser-assisted capsulorhexis in 2-6-year-old patients with congenital cataract

Background

To identify the capsule enlargement index after femtosecond laser-assisted anterior capsulorhexis in 2–6-year-old children who underwent congenital cataract surgery.

Methods

In this prospective case series study, femtosecond laser-assisted anterior capsulorhexis was performed in patients with congenital cataract, aged 2–6 years. The actual achieved capsulorhexis diameters were measured with Digimizer version 4.2.6. Correlation coefficient (r) and multiple linear regression analysis were used to evaluate the variables that could potentially influence anterior capsulorhexis enlargement index (E).

Results

This prospective study enrolled 28 eyes of 22 patients with congenital cataract. The mean age of the patients at surgery was 4.67 years ±1.54 (standard deviation [SD]). “E” of the 28 cases was 1.211 ± 0.039 (SD). Correlation analysis showed that “E” correlated significantly with the anterior chamber depth (ACD) (r = − 0.469, p = 0.021) and axial length (AL) (r = 0.452, p = 0.027). The following formula was developed by using multivariable linear regression analysis: Predicted E = 1.177–0.052 × ACD + 0.009 × AL, R² = 0.346 (F = 4.396, p = 0.046).

Conclusions

The anterior capsulorhexis enlargement index and its calculation formula could help to set up an accurate programmed capsulorhexis diameter for femtosecond laser-assisted congenital cataract surgery in children aged 2–6 years. Thus, an appropriate actual capsulorhexis diameter could be achieved.

Spiroplasma species as a rare cause of congenital cataract and uveitis: a case series

Background

To date, only four cases of ocular spiroplasma infection have been reported in the entire ophthalmic literature. We add two more cases to raise awareness of this sight-threatening congenital disease that manifests as cataract with ocular inflammation.

Case presentation

Both infants were referred for cataracts associated with ocular inflammation. Case 1, a 3-week-old neonate presented with unilateral cataract, ocular inflammation and elevated intraocular pressure. Case 2 was a 3-month-old infant with bilateral cataract and panuveitis. Lensectomies with or without vitrectomy and subsequent analyses of the specimens were performed. Transmission electron microscopy and multiplex polymerase chain reaction or 16 s rRNA gene polymerase chain reaction revealed spiroplasma species.

Conclusions

Spiroplasma as a very rare cause for congenital cataract might be underdiagnosed. We recommend performing polymerase chain reaction to probe for spiroplasma species in congenital cataracts with an inflammatory component.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12886-021-02201-0.

Optical biometry and influence of media opacity due to cataract on development of axial length in NorthEast Indian paediatric patients- A prospective study

AIM

To study the influence of media opacity due to cataract on the development of axial length in paediatric patients from North-East India, using optical biometry.

METHOD

This is a prospective, observational study, including consecutive patients attending the paediatric ophthalmology clinic, over a period of 1 year. Patients with other ocular and systemic diseases, unfit for optical biometry measurements due to dense cataract, nystagmus and strabismus were excluded and rest divided into three groups after proper age matching - 1. Group A (Bilateral cataract) 2. Group B (Unilateral cataract) 3. Group C (Bilateral normal). The axial length of the various groups was analysed using independent sample test (for bilateral cataract group) and paired t-test (for unilateral cataract group). Linear regression analysis between age and axial length was done.

RESULTS

A total of 177 patients were included.80 cases in Group A (bilateral cataract), 18 cases in Group B (unilateral cataract) and 79 in Group C (bilateral normal) The mean age of the patients in all the groups was 8.88 ± 3.51 years (range: 1-17 years). The bivariate analysis and simple linear regression revealed a statistically significant correlation between age and AL in case of cataractous eyes. (Pearson's coefficient: 0.341, p < 0.001). The mean AL was significantly longer (p = 0.013) in the cataractous eyes (mean = 23.38 ± 2.08 mm) of Group A(bilateral cataract) in the 7-12 years age group as compared to the bilaterally normal eyes (mean AL = 22.57 ± 0.70 mm) of patients in the same age group in Group C. The mean AL of cataractous eyes in group B (unilateral cataract) (mean = 22.46 ± 1.73 mm) as compared to the fellow normal eyes, (mean = 21.87 ± 0.97 mm) was not statistically significant.

CONCLUSION

Cataractous eyes have an abnormal axial length development. The influence of media opacity due to cataract on development of axial length in paediatric eyes in the North-East Indian population is variable, in line with global data on the same. Although there is some influence of media opacity, the exact nature is not clearly understood and may have a crucial interaction with genetic and other environmental factors. Genetic testing integrated with biometric analysis is recommended for further understanding of the ocular growth and development.

Outcomes of the infantile cataract surgery: case series with a 5-year follow-up

PURPOSE

To present the 5-year outcomes obtained from the infantile cataract surgery in pediatric population.

METHODS

Medical records of all patients with unilateral or bilateral infantile cataract who had undergone lensectomy and anterior vitrectomy with or without intraocular lens implantation before 10 years of age were evaluated. Patients with any history of ocular trauma, retinal or corneal dystrophy, ocular or orbital surgery, retinopathy of prematurity, raised intraocular pressure at the time of diagnosis, or incomplete follow-up sessions were excluded from the research.

RESULTS

A total of 85 eyes belonged to 52 patients were analyzed. Bilateral and unilateral diseases were present in 33 (63.5%) and 19 (36.5%) patients, respectively. After performing the first operation, 43 (50.6%) eyes still remained aphakic. The mean corrected distance visual acuity (CDVA) of the aphakic and pseudophakic eyes was estimated as 0.77 ± 0.52 and 0.43 ± 0.39 logMAR with no statistical difference. The age at the time of performing the cataract surgery was not associated with the final CDVA in either group. Complications in the anterior segment structures were noted in 39 (45%) eyes. Strabismus and amblyopia were noted in 52 (61%) and 75 (88.2%) eyes, respectively. Glaucoma was found in 17 (20%) eyes with no correlation with the final CDVA, age at the time of cataract surgery, or the status of the lens.

CONCLUSION

Due to high prevalence rates of amblyopia, strabismus, and glaucoma after the infantile cataract surgery, specific attention should be paid to these complications in each follow-up examination.

Steady state evoked potentials indicate changes in nonlinear neural mechanisms of vision in sight recovery individuals

Humans with a transient phase of congenital pattern vision deprivation have been observed to feature prevailing deficits, particularly in higher order visual functions. However, the neural correlates of these prevalent visual impairments remain unclear. To probe different visual processing stages, we measured steady state visual evoked potentials (SSVEPs) generated by luminance flicker stimuli at 6.1 Hz, with superimposed horizontal periodic motion at 2.1 Hz or 2.4 Hz. SSVEP responses at the fundamental and second harmonic of luminance flicker frequency, and at their intermodulation frequencies with motion information, were analyzed. Three groups were tested: (1) 15 individuals who had suffered a lack of pattern vision from birth due to the presence of bilateral total congenital cataracts (CC group), which were surgically removed between 4 months and 22 years of age, (2) 13 individuals with reversed developmental i.e., later developing cataracts (DC group), and (3) normally sighted control participants (SC group; n = 13) matched in age and sex to the CC individuals. SSVEPs at the second harmonic frequency (i.e., 12.2 Hz) and at the intermodulation frequencies (8.2 Hz, and 8.5 Hz) were attenuated in the CC group. In contrast, fundamental frequency responses (i.e., at 6.1 Hz) were not significantly altered in the CC group compared to the control groups (SC and DC groups). Based on previous evidence on the role of striate vs. extrastriate generators of fundamental vs. second harmonics of SSVEPs, these results provide evidence for a stronger experience dependence of extrastriate than striate cortical processing, and furthermore, suggest a sensitive period for the development of putative nonlinear neural mechanisms hypothesized to mediate visual feature binding.

The effect of retaining intact posterior capsule in congenital cataract surgery in children aged 4-8 years

Background

The present study sought to observe the effect of retaining intact posterior capsule in congenital cataract surgery in children aged 4–8 years.

Methods

This is a retrospective case control study. Seventy-seven children (130 eyes) aged from 4 to 8 years who underwent cataract surgery were divided into two groups. In Group A, 50 eyes underwent phacoemulsification, intraocular lens implantation and posterior capsule capsulotomy combined with anterior vitrectomy. In Group B, 80 eyes underwent cataract phacoemulsification and intraocular lens implantation. The postoperative visual acuity and the rate of complications were compared.

Results

In all patients, cataract surgeries were performed evenly without intraoperative complications. The follow-up time ranged from 6 months to 42 months. No apparent visual axis opacity was detected in group A during the follow-up. By the last visit, apparent visual axis opacity was detected in 31 eyes (38.75%) in group B. Among them, 9 eyes (29.03%) with mild posterior capsule opacification (PCO) were treated with Nd:YAG laser, 3 eyes (9.68%) with thick proliferative membranes were treated with posterior capsule capsulotomy combined with anterior vitrectomy and proliferative membranes in 19 eyes (61.29%) were completely aspired and the posterior capsule was retained. During follow-up, only 2 (6.45%) eyes had PCO recurrence and were treated with Nd:YAG laser. The visual acuity was significantly higher than that before surgery in all patients.

Conclusions

For older children, the incidence of PCO will be low even if intact posterior capsule is retained. Either Nd:YAG laser or surgical treatment for PCO will be able to maintain good vision.

Vision screening in newborns and early childhood

We looked at existing recommendations and supporting evidence on the effectiveness of screening for visual disorders in newborns and small infants, and in children between six months and five years of age.We conducted a literature search up to the 5th of August 2019 by using key terms and manual search in selected sources. We summarized the recommendations and the strength of the recommendations when and as reported by the authors. We summarized the main findings of systematic reviews with the certainty of the evidence as reported on the accuracy of screening tests for detecting visual alterations; the efficacy of treatment for improving visual acuity, school performance, and quality of life; and potential harms derived from vision screening and treating visual alterations.Although there is little evidence supporting its validity and effectiveness, examining all newborns for congenital cataract and retinoblastoma through the red reflex examination is widely accepted due to the severity of both diseases and the good outcomes reached by early detection and treatment.Overall, there is a moderate certainty of evidence that visual screening in children between three and five years provides a moderate net benefit, as assessed by the US Preventive Services Task Force: vision screening tests are accurate for detecting amblyopia and its risk factors, and their treatment is associated with visual improvement. There is uncertain evidence on whether vision screening in children under three years of age provides net benefits. Among populations with a low prevalence of vision abnormalities, screening the youngest is associated with an increased rate of false positives, leading to unnecessary additional assessment.

Swedish Parents' Experiences and Their Need for Support When Having a Child with Congenital Cataract: A Qualitative Study

PURPOSE

To explore parents' experiences of living with a child with congenital cataract, with the intention of identifying how to improve the parental support.

DESIGN AND METHOD

A qualitative descriptive design using semi-structured interviews. The parents were interviewed when the children were aged 12-24 months. All children were operated on for congenital cataract before three months of age. The interviews were transcribed and analysed using qualitative content analysis with an inductive approach. Findings were reported following the Standard for Reporting Qualitative Research (SRQR) checklist.

RESULTS

Three categories emerged from the data: trying to survive during a chaotic time; adapting to a different normal; being in need of support. When receiving the preliminary diagnosis, most of the parents were upset but managed well once the initial shock had subsided. However, some described feelings of despair, difficulties in accepting the situation and in connecting with the child. All parents stated that, to be valuable, a counsellor needed to have insights in how the eye works and the function of visual development.

CONCLUSION

The parents' need for psychosocial support in the early post-diagnostic stage varied greatly. Early identification of those in need of specialized counselling is therefore of importance, preferably at the maternity ward or by the regional ophthalmologist when the referral is made.

CLINICAL IMPLICATIONS

The study provides understanding of the importance to take the parents' well-being beyond the medical issues into consideration. This knowledge can be used to provide support at an earlier stage in the treatment programme than is currently the case.

Tribal Odisha Eye Disease Study (TOES). Report # 8. Childhood cataract surgery and determinants of visual outcome in tribal districts

Purpose

The purpose of this study is to describe the demographic profile, clinical features, visual outcomes, and follow-up patterns after successful cataract surgery in children from the tribal community in Odisha, India.

Methods

We retrospectively reviewed records of tribal children aged 4 months-16 years, who underwent public health financed cataract surgery at our institute from January 1, 2015, to December 31, 2019. Collected data included demographic profile, clinical features, outcomes, and follow-up. Univariate and multivariate linear regression identified factors affecting the visual outcome at a 6-week follow-up.

Results

During this period, a total of 352 children [536 eyes; mean age: 9.11 ± 4.4 years, 219 boys (62%)] underwent cataract surgery. The most common etiology and presenting complaints were idiopathic congenital cataract and decreased vision, respectively. In 304 children (86%), presenting best-corrected visual acuity (BCVA) was <20/200 (1.0 LogMAR), 113 (32%) had associated strabismus, and 57 (16%) had associated nystagmus. The public health agency did not sponsor postoperative follow-up, and only 195 (56%) and 61 (17.3%) children completed a 6-week and a 3-month follow-up, respectively. Median BCVA at 6-week and 3-month review was 20/125 (0.8, interquartile range [IQR], 0.2-2 LogMAR) and 20/60 (0.5, IQR, 0.25-1.35 LogMAR), respectively.

Conclusion

This study showed that children from the tribal community presented late with poor presenting VA and had suboptimal visual outcomes with inconsistent follow-ups. Greater advocacy, delivery of care closer to the place of residence, and financial support for follow-up care could improve early detection, regular evaluation, and outcomes.

Sengers syndrome: a rare case of cardiomyopathy combined with congenital cataracts in an infant: post-mortem case report

Sengers syndrome is a rare autosomal recessive disorder caused by a mutation in the Acylglycerol Kinase (AGK) gene with subsequent mitochondrial dysfunction. It is a combination of cardiomyopathy, skeletal myopathy, congenital bilateral cataracts, and lactic acidosis following exertion. The current study describes an extremely rare case of Sengers syndrome that is diagnosed during post-mortem examination. A four-month-old female child underwent sudden cardiac arrest immediately following the induction of general anesthesia for lens extraction surgery. This infant was the first child born to healthy, non-consanguineous, Egyptian parents. There were unremarkable medical problems either during pregnancy or during delivery. This infant was born at term with a normal APGAR score and weight. She had congenital bilateral cataracts since birth, easily-fatigued, and delayed milestones for her age. A post-mortem examination revealed a hypertrophied heart that weighed 96.6 grams with left ventricular hypertrophy. The left ventricle free wall thickness was 1cm, and an interventricular septum thickness of 1.3 cm. Histopathologically, the myocardium showed myocytes disarray. Also, the myocytes were hypertrophied, and vacuolated. The Gömöri trichrome stain revealed vacuolated cardiomyocytes surrounded by collagenous connective tissue, and the Periodic Acid Schiff (PAS) stain excluded that these vacuolations were related to glycogen storage disease. Focal lymphocytic infiltrations were observed within the myocardium. Thus, Sengers syndrome should be taken into consideration as a possible diagnosis whenever a congenital cataract is present for clinical and medicolegal cases.

Clinical and genetic findings in patients with congenital cataract and heart diseases

Background

Congenital cataract (CC) and congenital heart disease (CHD) are significant birth defects. In clinical practice, the concurrence of CC and CHD is frequently observed in patients. Additionally, some monogenic diseases, copy number variation (CNV) syndromes, and diseases associated with intrauterine infection involve both cataract and heart defects. However, little is known about the association between CC and CHD. Here, we characterised the demographic, clinical, and genetic features of patients with CC and heart defects.

Methods

Medical records for 334 hospitalised patients diagnosed with CC were reviewed. Demographic and clinical features of patients with CC with and without CHD were compared. Clinical and genomic information for patients with ‘cataract’ and ‘cardiac defects’ were reviewed from Database of Chromosomal Imbalance and Phenotype in Humans using Ensembl Resources (DECIPHER). Microarray-based comparative genomic hybridisation and whole-exome sequencing were performed in 10 trio families with CC and CHD to detect de novo genomic alterations, including copy number variants and single nucleotide changes.

Results

In a retrospective analysis of 334 patients with CC over the past 10 years at our hospital, we observed a high proportion of patients (41.13%) with CHD (including innocent CHD, which reported as left-to-right shunt in echocardiography test). The CC with CHD group had higher incidences of preterm birth and Down’s syndrome than the CC without CHD group. Atrial septal defect was the most frequent heart defect. A total of 44 cases with cataracts and heart diseases were retrieved from Database of Chromosomal Imbalance and Phenotype in Humans using Ensembl Resources (DECIPHER). In total, 52 genomic alterations were reported, 44% of which were de novo germline variants. In the 10 trio families with CC and CHD, we found de novo CNVs responsible for two well-known chromosomal disorders and identified a novel pathogenic mutation in GJA8 responsible for CC.

Conclusions

We observed significant associations between CHD and CC in our 10-year patient cohort. Based on the cohort and data from DECIPHER, developmental syndromes in some patients were due to genetic defects, thus explaining the concurrence of CC and CHD. Additionally, we detected de novo mutations as an independent cause of cataracts. Our findings suggest that developmental syndromes in patients with CC deserve more attention in clinical practice by ophthalmologists.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13023-021-01873-7.

Congenital ocular toxoplasmosis with torpedo maculopathy and retinopathy of prematurity in a premature baby

Purpose

To report an unusual case of congenital bilateral abnormality due to coexisting ocular toxoplasmosis and retinopathy of prematurity.

Observations

A prematurely born baby with bilateral retinopathy of prematurity (ROP) (one eye treated) was found to have a hyperpigmented torpedo maculopathy lesion in one eye while the other eye presented with microphthalmia, congenital cataract and non-specific pigmentary retinopathy. Following negative TORCH screening, laboratory tests subsequently revealed increased plasma IgG and IgM for toxoplasmosis.

Conclusions

We present an unusual case of coexistence of congenital ocular toxoplasmosis with torpedo maculopathy and retinopathy of prematurity.

ToRCH-screening in pediatric cataract revisited: A North Indian tertiary care centre study

Purpose:

To analyze and report ToRCH-serology screening profile (Toxoplasma gondii [TOX], rubella [RV], cytomegalovirus [CMV], and herpes simplex virus [HSV-I/II]) in pediatric cataract.

Methods:

In this prospective analytical study, 1,026 consecutive children were screened, of which 46 children with clinically diagnosed congenital (n = 26) and developmental cataract (n = 20) were included. Post-traumatic and familial cataracts were excluded. Sera of all children were tested both qualitatively and quantitatively for IgG/IgM-antibodies against ToRCH agents in a sequential manner.

Results:

Overall, IgM/IgG-seropositivity against ≥1 ToRCH agent was reported in 91.3% (42/46) children. IgM (±IgG) positivity against ≥1 ToRCH agent was reported in 26.08% (12/46) children (nine congenital and three developmental cataract; P = 0.18), which included 8.7% (4/46) children reported positive against ≥2 agents. Finally, 13% (6/46) children were reported to be sero-clinical-positive (three were infants and three were >1 year age, P = 0.55; five congenital and one developmental cataract, P = 0.21). Either alone or combined, RV attributed to the majority (50%; 6/12) of the IgM (±IgG) and sero-clinical-positive (50%; 3/6) children. None of the children were HSV-II IgM-positive. Laboratory-confirmed congenital rubella syndrome was reported in 4.3% (2/46) children. One sero-clinical-positive infant with rare coexisting bilateral persistent fetal vasculature was also reported. IgG-alone positivity was reported highest with CMV in 67.4% (31/46) children, whereas 43.4% (20/46) children were found nonimmune to RV.

Conclusion:

The current study emphasizes the need to interpret ToRCH-screening in pediatric cataract with caution. Interpretation should include both serial qualitative and quantitative assays in tandem with clinical correlation to minimize the diagnostic errors. Clinicians should remain vigilant regarding sero-clinical-positivity in older children too who might pose a threat to the spread of infection.