Should we aggressively treat unilateral congenital cataracts?

Analysis of age at detection and outcomes of dense unilateral congenital cataract surgery for children on the paediatric cataract register

AIM

Analysis of age at time of detection and surgery of dense unilateral cataract and investigation of best-corrected visual acuity (BCVA) in a nationwide register-based cohort study, based on the routine of maternity ward eye screening.

METHODS

Data were derived from the Paediatric Cataract Register (PECARE). All children (n = 54) diagnosed with dense congenital unilateral cataract between January 2007 and September 2014 who had surgery before 1 year of age, and for whom 5-year follow-up records were available, were included.

RESULTS

The majority, 35/54 (65%), were detected and operated on before age 6 weeks and 30/35 (86%) were referred from maternity wards. Visual acuity (VA) ≥ 0.5 (decimal, 0.3 logMAR) was found in 7/53 (13%) of the cohort at age 5 years; further, 19 children achieved VA ≥ 0.1 (decimal, 1.0 logMAR) (36%) and 19 children VA < 0.05 (decimal, 1.30 logMAR) (36%). Ten-year follow-up records were available for 17/53 (32%) children; 1/17 (6%) achieved VA ≥ 0.5 (decimal, 0.3 logMAR), 4/17 (24%) VA ≥ 0.3-<0.5 (decimal, 0.52-0.30 logMAR), 3/17 (18%) VA ≥ 0.05-0.1 (decimal, 1.30-1.0 logMAR) and 10/17 (59%) VA < 0.05 (decimal, 1.30 logMAR).

CONCLUSION

A total of 90% of the children were detected with cataract within 100 days of birth and 80% were operated on within this period. This study showed better visual acuity in those treated for dense unilateral cataracts than previously reported in an earlier Swedish cohort study.

Stereopsis following surgery in children with congenital and developmental cataracts: A systematic review and meta-analysis

We estimated the proportion of children with stereopsis following surgery in congenital and developmental cataracts by systematic review and meta-analysis and also considered the factors influencing stereopsis, such as intervention age and presence of strabismus. Stereopsis is directly related to quality of life, and investigating its levels following cataract surgery in children may help decide the right time to intervene, particularly in the context of brain plasticity. We conducted a systematic literature search using Scopus, PubMed, and Web of Science and found 25 case series, 3 cohorts, and 3 clinical trial studies from 1/1/1995 to 31/12/2020. Study-specific proportions of stereopsis from 923 children were pooled using a random-effects model, and stratified analyses were conducted based on intervention age and pre-existing strabismus as a confounder. We appraised the risk of bias using tools published by National Institutes of Health and evaluated publication bias with funnel plots and the Egger test. The pooled proportions of stereopsis based on 8 unilateral and 6 bilateral congenital cataract studies were 0.37 (95% CIs: [0.24, 0.53]) and 0.45 (95% CIs: [0.24,0.68]) when patients with preexisting strabismus were excluded as a confounder. When the intervention age was ≤6 months, proportions in unilateral congenital cataract group significantly increased to 0.52 (95% CIs: [0.37, 0.66]; P = 0.49) compared to 0.26 (95% CIs: [0.14, 0.44]; P = 0.16) otherwise. A similar increase in proportions was found when intervention age ≤4 months. In both unilateral and bilateral congenital cataract groups, proportions increased significantly when the confounder was excluded. Overall, proportions in bilateral congenital cataracts were significantly greater than unilateral cases (irrespective of confounder). Eight unilateral and 5 bilateral developmental cataract studies resulted in pooled proportions of 0.62 (95% CIs: [0.27, 0.88] and 0.82 (95% CIs: [0.4, 0.97]), respectively. Although proportions for bilateral developmental cataracts were greater than unilateral cataracts (irrespective of confounder), results were not statistically significant. Finally, proportions in unilateral developmental cataracts were significantly greater than unilateral congenital cataracts (Z = 7.413, P = 6.173694e-14). We conclude that surgical intervention within first 4-6 months can significantly affect postoperative outcomes in unilateral congenital cataracts. Analysis of existing data does not show a significant effect of intervention age on stereopsis outcomes for developmental cataracts.

Barriers and enablers to access childhood cataract services across India. A qualitative study using the Theoretical Domains Framework (TDF) of behaviour change

Early presentation for childhood cataract surgery is an important first step in preventing related visual impairment and blindness. In the absence of neonatal eye screening programmes in developing countries, the early identification of childhood cataract remains a major challenge. The primary aim of this study was to identify potential barriers to accessing childhood cataract services from the perspective of parents and carers, as a critical step towards increasing the timely uptake of cataract surgery. In-depth interviews were conducted using a pre-designed topic guide developed for this study to seek the views of parents and carers in nine geographic locations across eight states in India regarding their perceived barriers and enablers to accessing childhood cataract services. A total of 35 in-depth interviews were conducted including 30 at the hospital premises and 5 in the participants' homes. All interviews were conducted in the local language and audio taped for further transcription and analysis. Data were organised using NVivo 11 and a thematic analysis was conducted utilising the Theoretical Domains Framework (TDF), an integrative framework of behavioural theories. The themes identified from interviews related to 11 out of 12 TDF domains. TDF domains associated with barriers included: 'Environmental context and resources', 'Beliefs about consequences' and 'Social influences'. Reported enablers were identified in three theoretical domains: 'Social influences', 'Beliefs about consequences' and 'Motivations and goals'. This comprehensive TDF approach enabled us to understand parents' perceived barriers and enablers to accessing childhood cataract services, which could be targeted in future interventions to improve timely uptake.

Abnormal Red Reflex: Etiologies in a Pediatric Ophthalmology Population

Children who present with an abnormal red reflex (ARR) are often referred to ophthalmology due to concern for retinoblastoma. However, an ARR can indicate a wide variety of pathologies, all of which have the potential to develop amblyopia and irreversible vision loss. In this retrospective cohort study, we demonstrate that children who presented with an ARR had a mean age of 22.0 ± 32.5 months and were more frequently referred by their pediatricians (74.5%). The majority of these patients (61.8%) had a normal examination on further evaluation, followed by refractive error (20.4%). Amblyopia was diagnosed in 83.9% of patients with refractive error, with a mean age of 50.3 ± 49.2 months. Because many ARR-associated pathologies require time-sensitive treatment to prevent vision loss, proper screening is critical for diagnosis. Pediatricians play a key role in screening, so education on more common ARR pathologies can better facilitate referrals and improve outcomes.

Role of a Community-based Program for Identification and Referral of Pediatric Cataract Patients in Kinshasa, Democratic Republic of the Congo

PURPOSE

The purpose of this study is to describe the methodology and to assess the effectiveness of a community-based rehabilitation (CBR) program to identify and refer children with blinding cataract for the management and surgery to reduce the burden of childhood blindness due to cataract in Kinshasa.

METHODS

Church-based volunteers were trained to identify children with presumed eye disorders in their localities and households and to refer them for cataract identification by an ophthalmic nurse during parishes' visits. Volunteers were parishioners living in the quartiers where identification took place and worked as community workers with the CBR program. Nurses used a lamp-torch to rule out cataract. Selected children were referred to the tertiary eye health facility at St Joseph Hospital for diagnosis and management.

RESULTS

Identification took place in 31 out of 165 parishes in the Archdioceses of Kinshasa from 2000 to 2016 and 11,106 children aged <16 years were screened. Among them, 1277 children (11.5%) were presumed to have cataract. Ninety-two children among them died before surgery; 107 children were lost to further follow-up and did not report to the CBR center for referral. Reasons given were change of home address, moving in their lieu of origin, death, and refusal of treatment by the parents. Finally, only 1078 children were referred to the pediatric ophthalmologist and 705 children (65.4%) were definitively diagnosed to have treatable cataract, while in 373 children (34.6%), cataract surgery was not indicated for several reasons. There was a positive history of familial cataract in 36 children (2.8%).

CONCLUSION

Using church-based volunteers and ophthalmic nurses during community screening proved efficient in the identification and referral of pediatric cataract. Keeping regular identification activities in the community and maintaining high-quality and accessible pediatric cataract surgery services can help to clear up the backlog of cataract blind children.

Delay in presentation to hospital for childhood cataract surgery in India

Purpose

Cataract is one of the major causes of avoidable visual disability in children and the aim of this study was to investigate the age at which children with cataract present for surgery at tertiary hospitals across India.

Methods

A prospective multicenter study collected data from 9 eye hospitals in 8 states in India. All children admitted for cataract surgery between Nov 2015 and March 2016 were considered eligible. Parents were interviewed at the hospital by trained personnel and socio demographic information, age at diagnosis and at surgery and the relevant clinical data were obtained from the medical records. Mean age, age range at surgery were used and performed logistic regression analyses.

Results

Parents of 751 consecutive cases were interviewed, of which 469(63%) were boys and 548 (73%) were from rural areas. Cataract was bilateral in 493 (66%) and unilateral in 258 (34%); of the unilateral cases, 179 (69%) were due to trauma. The mean age at surgery for ‘congenital’ and ‘developmental’ cataract was 48.2 ± 50.9 and 99.7 ± 46.42 months, respectively and the mean age was lower in the southern region compared to other regions. Children with 2 or more siblings at home were five times more likely to undergo surgery within 12 months (OR, 4.69; 95% CI: 2.04–10.79; p = < 0.001).

Conclusions

Late surgery for childhood cataract remains a major challenge and the factors determining this issue in India are pertinent also to several other countries and need to be addressed for every child with cataract to achieve full visual potential.

Trypan blue-assisted posterior capsulorhexis in pediatric cataract surgery

PURPOSE

To evaluate the safety and efficacy of staining the posterior capsule with trypan blue during capsulorhexis in pediatric cataract surgery.

PATIENTS AND METHODS

This was a prospective randomized comparative study carried out at Alpha Vision Center, Zagazig, Egypt. This study included 2 groups of children with pediatric cataract randomly allocated to undergo irrigation and aspiration. In the trypan group, which included 11 eyes, trypan blue was used to stain the posterior capsule during posterior capsulorhexis. In the control group, which included 10 eyes, no staining was performed. All surgeries were performed by the same surgeon. The 2 groups were compared for criteria such as completion of capsulorhexis, disruption of vitreous face and in-the-bag intraocular lens implantation.

RESULTS

This study included 21 eyes of 16 patients (age range: 6 months-4 years). A statistically significant difference was observed for the following parameters between the 2 groups: capsulorhexis completion (P=0.04), vitreous face disruption (P=0.01) and in-the-bag intraocular lens implantation (P=0.022).

CONCLUSION

This study suggests that staining of the posterior capsule during capsulorhexis in pediatric cataract operation gives better results than capsulorhexis without staining. The stain changes the capsule texture making capsulorhexis easier with fewer complications.

Pediatric cataract: challenges and future directions

Cataract is a significant cause of visual disability in the pediatric population worldwide and can significantly impact the neurobiological development of a child. Early diagnosis and prompt surgical intervention is critical to prevent irreversible amblyopia. Thorough ocular evaluation, including the onset, duration, and morphology of a cataract, is essential to determine the timing for surgical intervention. Detailed assessment of the general health of the child, preferably in conjunction with a pediatrician, is helpful to rule out any associated systemic condition. Although pediatric cataracts have a diverse etiology, with the majority being idiopathic, genetic counseling and molecular testing should be undertaken with the help of a genetic counselor and/or geneticist in cases of hereditary cataracts. Advancement in surgical techniques and methods of optical rehabilitation has substantially improved the functional and anatomic outcomes of pediatric cataract surgeries in recent years. However, the phenomenon of refractive growth and the process of emmetropization have continued to puzzle pediatric ophthalmologists and highlight the need for future prospective studies. Posterior capsule opacification and secondary glaucoma are still the major postoperative complications necessitating long-term surveillance in children undergoing cataract surgery early in life. Successful management of pediatric cataracts depends on individualized care and experienced teamwork. We reviewed the etiology, preoperative evaluation including biometry, choice of intraocular lens, surgical techniques, and recent developments in the field of childhood cataract.

Lens particle glaucoma secondary to untreated congenital cataract and persistent fetal vasculature

Purpose. To present a case of lens particle glaucoma in a child with an untreated unilateral congenital cataract and persistent fetal vasculature (PFV) and to discuss the implications for the management of unilateral congenital cataract.
Methods. A 4-year-old boy presented with a unilateral congenital cataract affecting the right eye. Examination revealed a cataract and PFV. Intraocular pressure (IOP) measured 18 mmHg right, 14 mmHg left, and he was managed conservatively. Nine months later, he attended clinic with a painful right eye. He had quiet anterior and posterior segments but free lens particles in the anterior vitreous and an IOP of 12 mmHg. Over 4 weeks, the IOP rose to 23 mmHg and the patient underwent vitreolensectomy.
Results. The affected eye has at no point become inflamed but macrophages laden with lens proteins were identified during histopathologic analysis of the vitreous. The proposed mechanism in this case is that the PFV weakened the posterior capsule leading to its rupture. The resultant macrophages then caused mechanical obstruction of aqueous outflow through the trabecular meshwork.
Conclusions. Lens particle glaucoma secondary to posterior capsular rupture is a rare form of lens-induced glaucoma. It is common practice to manage conservatively those patients who present late with unilateral congenital cataract. This case highlights the need for vigilant follow-up of these patients to enable lens-induced glaucoma to be detected at an early stage.

Long-term results of pediatric cataract surgery after delayed diagnosis

PURPOSE

To report the long-term rates of visual impairment in children who underwent cataract surgery after late diagnosis.

METHODS

The records of children who underwent cataract surgery in northern China between January 1994 and December 2009 were retrospectively reviewed. Age at surgery, surgical approach, postoperative best-corrected visual acuity, and compliance with amblyopia treatment were evaluated. Visual impairment was defined as best-corrected visual acuity <20/60.

RESULTS

Of 486 children included in this study, 2 (0.4%) had surgery by age 3 months and 68 (14%) by age 6 months. Of the 536 eyes of 331 patients with visual acuity recorded at final follow-up, 151 eyes (37%) had bilateral cataract and 82 (65%) had unilateral cataract, with a total of 233 (45%) considered visually impaired. In children who had surgery before 36 months of age for bilateral cataracts, there was no significant difference in rates of visual impairment with versus without primary IOL implantation. In patients with unilateral cataract, visual impairment occurred regardless of age at surgery or whether IOL was primarily implanted. Postoperatively, compliance with amblyopia treatment was good in 30% of patients, fair in 45%, and poor in 31%.

CONCLUSIONS

The long-term visual acuity was unfavorable in approximately half of children diagnosed and treated for pediatric cataracts after 3 months of age. Contributing factors included age at presentation and absence of effective training for postoperative vision rehabilitation.

Clinical and experimental advances in congenital and paediatric cataracts

Cataracts (opacities of the lens) are frequent in the elderly, but rare in paediatric practice. Congenital cataracts (in industrialized countries) are mainly caused by mutations affecting lens development. Much of our knowledge about the underlying mechanisms of cataractogenesis has come from the genetic analysis of affected families: there are contributions from genes coding for transcription factors (such as FoxE3, Maf, Pitx3) and structural proteins such as crystallins or connexins. In addition, there are contributions from enzymes affecting sugar pathways (particularly the galactose pathway) and from a quite unexpected area: axon guidance molecules like ephrins and their receptors. Cataractous mouse lenses can be identified easily by visual inspection, and a remarkable number of mutant lines have now been characterized. Generally, most of the mouse mutants show a similar phenotype to their human counterparts; however, there are some remarkable differences. It should be noted that many mutations affect genes that are expressed not only in the lens, but also in tissues and organs outside the eye. There is increasing evidence for pleiotropic effects of these genes, and increasing consideration that cataracts may act as early and readily detectable biomarkers for a number of systemic syndromes.

Emmetropization after lensectomy and anterior vitrectomy for persistent hyperplastic primary vitreous cataract

PURPOSE

To report the case of a 2-year-old boy whose aphakic eye became emmetropic 15 months after lensectomy with anterior vitrectomy for a classic persistent hyperplastic primary vitreous cataract.

METHODS

Retrospective case report.

RESULTS

Emmetropization of the aphakic eye was caused by corneal steepening and axial elongation. At 2 years old, the child would fixate and follow with either eye.

CONCLUSIONS

In this patient, the fortunate combination of axial elongation and corneal steepening resulted in the aphakic eye's developing a plano refraction and thus becoming more amenable to amblyopia treatment.

Pediatric Keratoprosthesis

OBJECTIVE

To describe the authors' experience using keratoprosthesis to treat pediatric corneal opacity.

DESIGN

Nonrandomized, consecutive, retrospective interventional series.

PARTICIPANTS

Twenty-two eyes of 17 children with opaque corneas as a result of primary congenital disease and or previous failed keratoplasty.

METHODS

A retrospective review of pediatric patients with a history of corneal opacification treated with keratoprosthesis surgery.

MAIN OUTCOME MEASURES

Intraocular pressure, inflammation, clarity of the visual axis, visual acuity, refraction, complications, and retention of the prosthesis.

RESULTS

Twenty-two eyes of 17 patients 1.5 to 136 months of age underwent 23 keratoprosthesis procedures. The follow-up period was 220 patient months (range, 1-37 months; mean, 9.7 months). In both cases implanted with the AlphaCor (Argus Biomedical Pty. Ltd., Perth, Australia), the keratoprosthesis was not retained. In one instance, the prosthesis sustained traumatic dislocation and was replaced with a cadaver cornea. In the second instance, the intralamellar implant began to extrude and was replaced with a Boston keratoprosthesis. In all 21 Boston cases, the prosthesis was retained without dislocation or extrusion. The visual axis remained clear in 100% of cases, although retroprosthetic membranes were removed in 5 eyes. Reoperation was necessitated for management of concurrent glaucoma (n = 3) or retinopathy (n = 2). There were no instances of surface infection or endophthalmitis. In 7 instances where patient age was 4 years or more, visual acuity ranged from counting fingers to 20/30. In the remaining cases, all infants were able to follow light, fingers, and objects. Intraocular pressure was controlled in all cases.

CONCLUSIONS

Implantation of the Boston keratoprosthesis rapidly establishes and maintains a clear optical pathway and does not prejudice management of concurrent glaucoma or retinopathy. The device is retained without extrusion or rejection and is appropriate for the management of pediatric corneal opacity.

Evidence of binocular fusion in a 3-week-old infant with transient abducens nerve paresis

We report an infant with clinical evidence of binocular fusion at 3 weeks of life. To the best of our knowledge, this is the first report providing evidence of binocularity in the first month of life.

2005 Gregg Lecture: Congenital cataract--from rubella to genetics

On the 65th anniversary of Gregg's observation "Congenital cataract following German measles in the mother", rubella has retired as the leading cause of congenital cataract, from 87% of Gregg's cohort to less than 3% over the last 25 years and almost zero now in Australia and other developed countries. However, people must keep vigilance in maintaining immunization rates and encourage immunization in developing countries. At least one-fifth of congenital cataract is familial. Understanding the genetics of familial cataract will lead to better treatment of congenital as well as age-related cataract.

Recovery of Cortical Binocularity and Orientation Selectivity After the Critical Period for Ocular Dominance Plasticity

Cortical binocularity is abolished by monocular deprivation (MD) during a critical period of development lasting from approximately postnatal day (P) 35 to P70 in ferrets. Although this is one of the best-characterized models of neural plasticity and amblyopia, very few studies have examined the requirements for recovery of cortical binocularity and orientation selectivity of deprived eye responses. Recent studies indicating that different mechanisms regulate loss and recovery of binocularity raise the possibility that different sensitive periods characterize loss and recovery of deprived eye responses. In this report, we have examined whether the potential for recovery of binocularity and orientation selectivity is restricted to the critical period. Quantitative single unit recordings revealed recovery of cortical binocularity and full recovery of orientation selectivity of deprived eye responses following prolonged periods of MD (i.e., >3 wk) starting at P49, near the peak of plasticity. Surprisingly, recovery was present when binocular vision was restored after the end of the critical period for ocular dominance plasticity, as late as P83. In contrast, ferrets that had never received visual experience through the deprived eye failed to recover binocularity even though normal binocular vision was restored at P50, halfway through the critical period. Collectively, these results indicate that there is potential for recovery of cortical binocularity and deprived eye orientation selectivity after the end of the critical period for ocular dominance plasticity.