One-year strabismus outcomes in the Infant Aphakia Treatment Study

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Strabismus and Nystagmus in Patients With Pediatric Cataracts: Study Using Insurance Claims Data

PURPOSE

To describe the characteristics and prevalence of strabismus and nystagmus in children diagnosed with cataracts using a national insurance claims database.

DESIGN

Population-based retrospective cohort study.

METHODS

Patients aged <13 years diagnosed with cataracts (traumatic cataracts excluded) and enrolled continuously in their health care program for ≥5 years after their first cataract diagnosis were identified in a retrospective review of 66 million charts in Optum's de-identified Clinformatics Data Mart Database between 2003 and 2015. Patients were categorized based on age of their first diagnosed cataract, and if cataract surgery was performed. Clinical and demographic factors associated with the occurrence of strabismus and nystagmus were evaluated.

RESULTS

Of 1636 children diagnosed with cataract, 434 (26.5%) and 109 (6.7%) were diagnosed with strabismus and nystagmus, respectively. Both strabismus and nystagmus were more common in those who underwent cataract surgery (P < .001) and in patients diagnosed with cataract at ≤12 months of age (P < .001). Survival analysis demonstrated that strabismus and nystagmus may be diagnosed 8 years after the initial cataract diagnosis. Cox proportional hazard regression analyses revealed strabismus was associated with cataract surgery, nystagmus, and the diagnosis with cataract at ≤12 months and cataract surgery at >12 months.

CONCLUSIONS

As strabismus and nystagmus occur more frequently in children diagnosed with cataracts necessitating cataract surgery, regular long-term follow-up is crucial for these children to monitor for the development of strabismus and nystagmus.

Surgical Outcomes of Lensectomy-Vitrectomy with Primary Intraocular Lens Implantation in Children with Bilateral Congenital Cataracts

In this study, we evaluated the long-term surgical outcomes of lensectomy-vitrectomy with primary intraocular lens (IOL) implantation in children with bilateral congenital cataracts (CCs) and investigated the potential risk factors for low vision. A total of 148 eyes in 74 children who underwent lensectomy-vitrectomy with primary IOL implantation were enrolled in this study. The surgery age was 44.04 ± 14.60 months, with a follow-up period of 46.66 ± 14.34 months. The final BCVA was 0.24 ± 0.32 logMAR, and low vision was found in 22 eyes (14.9%). Postoperative complications requiring additional surgeries included VAO (4 eyes, 5.4%), IOL pupillary captures (2 eyes, 2.0%), iris incarceration (1 eye, 0.7%), and glaucoma (1 eye, 0.7%). A higher incidence of VAO and larger postoperative refractive error was observed in younger children (≤2 years old) than in elder children (>2 years old) (p = 0.003, p = 0.047, respectively). Final BCVA was affected by preexisting comorbidity (p < 0.001), cataract density (p < 0.001), cataract size (p = 0.020), occurrence of postoperative complications (p = 0.011), and ASE (p = 0.008). Multivariate analysis showed that denser cataracts (OR = 9.303, p = 0.035) and preexisting comorbidity (OR = 4.712, p = 0.004) were the significant predictors of low vision. In conclusion, lensectomy-vitrectomy with primary IOL implantation is an effective and safe treatment for CC. The long-term visual outcome is encouraging in children with bilateral CC undergoing this procedure with a low rate of postoperative complications requiring surgeries. Moreover, eyes with denser cataracts and preexisting comorbidity may have a high risk of low vision.

Long-term strabismus outcomes after unilateral infantile cataract surgery in the Infant Aphakia Treatment Study

PURPOSE

To characterize long-term strabismus outcomes in children in the Infant Aphakia Treatment Study (IATS).

METHODS

This study was a secondary data analysis of long-term ocular alignment characteristics of children aged 10.5 years who had previously been enrolled in a randomized clinical trial evaluating aphakic management after unilateral cataract surgery between 1 and 6 months of age.

RESULTS

In the IATS study, 96 of 109 children (88%) developed strabismus through age 10.5 years. Half of the 20 children who were orthophoric at distance through age 5 years maintained orthophoria at distance fixation at 10.5 years. Esotropia was the most common type of strabismus prior to age 5 years (56/109 [51%]), whereas exotropia (49/109 [45%]) was the most common type of strabismus at 10.5 years (esotropia, 21%; isolated hypertropia, 17%). Strabismus surgery had been performed on 52 children (48%), with 18 of these (35%) achieving microtropia <10^Δ. Strabismus was equally prevalent in children randomized to contact lens care compared with those randomized to primary intraocular lens implantation (45/54 [83%] vs 45/55 [82%]; P = 0.8). Median visual acuity in the study eye was 0.56 logMAR (20/72) for children with orthotropia or microtropia <10^Δ versus 1.30 logMAR (20/400) for strabismus ≥10^Δ (P = 0.0003).

CONCLUSIONS

Strabismus-in particular, exotropia-is common irrespective of aphakia management 10 years following infant monocular cataract surgery. The delayed emergence of exotropia with longer follow-up indicates a need for caution in managing early esotropia in these children. Children with better visual acuity at 10 years of age are more likely to have better ocular alignment.

Femtosecond laser-assisted anterior capsulotomy in children undergoing cataract surgery: a large case series

Objective

To evaluate safety and postoperative visual outcomes of low-energy femtosecond laser-assisted (FLA) anterior capsulotomy in paediatric cataract surgery.

Methods and analysis

We report a retrospective single-centre consecutive case series of 51 eyes of 33 paediatric cataract patients with a mean age of 3.22 years (range: 2 months to 13 years) who underwent cataract surgery with FLA anterior capsulotomy, using FEMTO LDV Z8 femtosecond laser (Ziemer Ophthalmic Systems). Anterior laser capsulotomy, phacoaspiration and intraocular lens implantation were performed in all eyes. Both intraoperative and long-term postoperative complications, along with long-term monocular corrected distance visual acuity (CDVA), were assessed during average follow-up period of 32.96 months (range: 13–69 months).

Results

In 48 out of 51 eyes, a well-sized and well-located anterior capsulotomy was achieved without intraoperative complications. Anterior capsule tears occurred in three eyes; however, they did not extend posteriorly and the intraocular lens were placed in the bags without any further complications. Posterior capsular opacification developed in 45.10% of eyes (23 out of 51) and was subsequently treated with neodymium:yttrium-aluminum-garnet (Nd:YAG) laser capsulotomy. Mean CDVA at final follow-up was 20/40 (range: 20/63 to 20/32) in unilateral cases younger than 12 months, 20/40 (range: 20/1000 to 20/25) in unilateral cases older than 12 months, 20/66 (range: 20/400 to 20/32) in bilateral cases younger than 12 months and 20/40 (range: 20/200 to 20/20) in bilateral cases older than 12 months.

Conclusions

Paediatric cataract surgery with low-energy FLA anterior capsulotomy is a procedure with long-term safety, resulting in significant improvement in CDVA.

Outcomes of Bilateral Congenital and Developmental Cataracts Following IOL Implantation in Preschool Children

PURPOSE

To evaluate the different ocular outcomes and the potential factors affecting visual acuity in bilateral congenital cataracts and developmental cataracts after intraocular lens implantation in preschool children.

METHODS

In a retrospective study, 86 eyes (51 congenital and 35 developmental cataract cases) of 43 children aged 6 years and younger who were diagnosed as having bilateral cataracts and underwent cataract aspiration combined with primary or secondary foldable intraocular lens implantation between 2003 and 2018 were reviewed. A minimum of 1 year of follow-up was required. The best corrected visual acuity (BCVA) and the factors associated with visual results were explored.

RESULTS

The postoperative BCVA in the developmental cataract group (0.20 ± 0.19 logarithm of the minimum angle of resolution [logMAR]) was significantly better than that in the congenital cataract group (0.57 ± 0.31 logMAR) (P < .001). The mean refractive error was 3.61 ± 3.03 diopters in the congenital cataract group and 2.15 ± 1.82 diopters in the developmental cataract group. All cases of strabismus and nystagmus were found in the congenital cataract group. In the congenital cataract group, the variables age at cataract extraction and refractive error were significantly associated with BCVA (P < .001, P = .001, respectively). These variables had little effect on the developmental cataract group (P = .971, P = .576, respectively). Postoperative complications were recorded in 18 eyes: 4 in the developmental cataract group and 14 in the congenital cataract group.

CONCLUSIONS

The BCVA in the developmental cataract group was significantly better than that in the congenital cataract group. The therapeutic effects of patients with congenital cataracts and developmental cataracts should be evaluated separately. [J Pediatr Ophthalmol Strabismus. 2021;58(3):180-187.].

Preoperative Predictors for Esodeviation and Exodeviation after Cataract Surgery in Children

Purpose: For those children that went on to have strabismus surgery after cataract surgery, we sought to identify preoperative predictors for whether strabismus surgery would be for an esodeviation or for an exodeviation.Design: Retrospective studyMethods: Charts of patients <18 years who underwent cataract surgery were reviewed. Data from the first strabismus surgery after cataract surgery were reviewed. Statistical analysis was performed using T-test for continuous variable and chi-square test for categorical variable. A binomial logistic regression was performed to ascertain the effects of variables that were found to be significant.Results: 142 patients were identified having strabismus surgery. Type of deviation at first strabismus surgery was: Esodeviation: 72 (50.7%), exodeviation 55 (38.7%), and surgery for only vertical strabismus 15 (10.6%). Age at cataract surgery was an independent variable determining subsequent surgery for esodeviation or exodeviation. For each year increase in age at cataract surgery, the odds of having surgery for exotropia instead of esotropia increases by a factor of 1.620 (P = .005). Odds that strabismus surgery will be for exodeviation is 4.9 times higher in children who had cataract surgery at 1 year of age or greater as compared to children <1 year of age (P < .001).Conclusion: For those children who went on to have strabismus surgery after cataract surgery, younger age at cataract surgery increases the chance that subsequent strabismus surgery will be for an esodeviation. Those who had cataract surgery at an older age were more likely to have surgery for exotropia than for esotropia.

An electrophysiological biomarker for the classification of cataract-reversal patients: A case-control study

BACKGROUND

Untreated congenital blindness through cataracts leads to lasting visual brain system changes, including substantial alterations of extrastriate visual areas. Consequently, late-treated individuals (> 5 months of age) with dense congenital bilateral cataracts (CC) exhibit poorer visual function recovery compared to individuals with bilateral developmental cataracts (DC). Reliable methods to differentiate between patients with congenital and developmental cataracts are often lacking, impeding efficient rehabilitation management and introducing confounds in clinical and basic research on recovery prognosis and optimal timing of surgery. A persistent reduction of the P1 wave of visual event-related potentials (VERPs), associated with extrastriate visual cortical activity, has been reported in CC but not in DC individuals. Using two experiments, this study developed and validated P1-based biomarkers for diagnosing a history of congenital blindness in cataract-reversal individuals.

METHODS

Congenital and developmental cataract-reversal individuals as well as typically sighted matched controls took part in a first experiment used for exploring an electrophysiological biomarker (N _CC = 13, N _DC = 13, N _Control = 26). Circular stimuli containing gratings were presented in one of the visual field quadrants while visual event-related potentials (VERPs) were recorded. Two biomarkers were derived from the P1 wave of the VERP: (1) The mean of the normalized P1 amplitude at posterior electrodes, and (2) a classifier obtained from a linear support vector machine (SVM). A second experiment with partially new CC/DC individuals and their matched controls (N _CC = 14, N _DC = 15, N _Control = 29) was consecutively used to validate the classification based on both biomarkers. Performance of the classifiers were evaluated using receiver operating characteristic (ROC) curve analyses. All cataract-reversal individuals were tested after at least one year of vision recovery.

FINDINGS

The normalized P1 amplitude over posterior electrodes allowed a successful classification of the CC from the DC individuals and typically sighted controls (area under ROC curve, AUC = 0.803 and 0.929 for the normalized P1 amplitude and the SVM-based biomarker, respectively). The validation for both biomarkers in experiment 2 again resulted in a high classification success (AUC = 0.800 and 0.883, respectively for the normalized P1 amplitude and the SVM-based biomarker). In the most conservative scenario involving classification of CC from DC individuals in a group of only cataract-reversal individuals, excluding typically sighted controls, the SVM-based biomarker was found to be superior to the mean P1 amplitude based biomarker (AUC = 0.852 compared to 0.757 for the mean P1 based biomarker in validation). Minimum specificity obtained was 80% across all biomarkers.

INTERPRETATION

A persistent reduction of the P1 wave provides a highly specific method for classifying cataract patients post-surgically as having suffered from bilateral congenital vs. bilateral developmental cataracts. We suggest that using the P1 based non-invasive electrophysiological biomarker will augment existing clinical classification criteria for individuals with a history of bilateral congenital cataracts, aiding clinical and basic research, recovery prognosis, and rehabilitation efforts.

FUNDING

German Research Foundation (DFG) and the European Research Council (ERC).

Cataract management in children: a review of the literature and current practice across five large UK centres

Congenital and childhood cataracts are uncommon but regularly seen in the clinics of most paediatric ophthalmology teams in the UK. They are often associated with profound visual loss and a large proportion have a genetic aetiology, some with significant extra-ocular comorbidities. Optimal diagnosis and treatment typically require close collaboration within multidisciplinary teams. Surgery remains the mainstay of treatment. A variety of surgical techniques, timings of intervention and options for optical correction have been advocated making management seem complex for those seeing affected children infrequently. This paper summarises the proceedings of two recent RCOphth paediatric cataract study days, provides a literature review and describes the current UK 'state of play' in the management of paediatric cataracts.

Outcomes of Bilateral Cataracts Removed in Infants 1 to 7 Months of Age Using the Toddler Aphakia and Pseudophakia Treatment Study Registry

PURPOSE

To evaluate outcomes of bilateral cataract surgery in infants 1 to 7 months of age performed by Infant Aphakia Treatment Study (IATS) investigators during IATS recruitment and to compare them with IATS unilateral outcomes.

DESIGN

Retrospective case series review at 10 IATS sites.

PARTICIPANTS

The Toddler Aphakia and Pseudophakia Study (TAPS) is a registry of children treated by surgeons who participated in the IATS.

METHODS

Children underwent bilateral cataract surgery with or without intraocular lens (IOL) placement during IATS enrollment years 2004 through 2010.

MAIN OUTCOME MEASURES

Visual acuity (VA), strabismus, adverse events (AEs), and reoperations.

RESULTS

One hundred seventy-eight eyes (96 children) were identified with a median age of 2.5 months (range, 1-7 months) at the time of cataract surgery. Forty-two eyes (24%) received primary IOL implantation. Median VA of the better-seeing eye at final study visit closest to 5 years of age with optotype VA testing was 0.35 logarithm of the minimum angle of resolution (logMAR; optotype equivalent, 20/45; range, 0.00-1.18 logMAR) in both aphakic and pseudophakic children. Corrected VA was excellent (<20/40) in 29% of better-seeing eyes, 15% of worse-seeing eyes. One percent showed poor acuity (≥20/200) in the better-seeing eye, 12% in the worse-seeing eye. Younger age at surgery and smaller (<9.5 mm) corneal diameter at surgery conferred an increased risk for glaucoma or glaucoma suspect designation (younger age: odds ratio [OR], 1.44; P = 0.037; and smaller cornea: OR, 3.95; P = 0.045). Adverse events also were associated with these 2 variables on multivariate analysis (younger age: OR, 1.36; P = 0.023; and smaller cornea: OR, 4.78; P = 0.057). Visual axis opacification was more common in pseudophakic (32%) than aphakic (8%) eyes (P = 0.009). Unplanned intraocular reoperation occurred in 28% of first enrolled eyes (including glaucoma surgery in 10%).

CONCLUSIONS

Visual acuity after bilateral cataract surgery in infants younger than 7 months is good, despite frequent systemic and ocular comorbidities. Although aphakia management did not affect VA outcome or AE incidence, IOL placement increased the risk of visual axis opacification. Adverse events and glaucoma correlated with a younger age at surgery and glaucoma correlated with the presence of microcornea.

Evaluation of eye-related parameters and adverse events of rigid gas permeable contact lens and spectacles correction in infants with monocular aphakia after congenital cataract surgery: a retrospective clinical study

Background

Congenital cataract is currently one of the leading blindness-causing eye diseases in children. Surgical treatment only opens the visual pathway for children. The postoperative recovery of visual function is also dependent on effective optical correction and visual function training. In this study, we analyzed the changes in eye-related parameters, adverse events and the annual cost of rigid gas permeable contact lens (RGPCL) and spectacles correction in infants with monocular aphakia after congenital cataract surgery.

Methods

To analyze the postoperative visual acuity, strabismus, nystagmus, myopic shift, globe axial length growth, adverse events, patient adherence to patching, and annual cost for patients with unilateral congenital cataract who underwent cataract surgery. Rigid gas permeable contact lenses or spectacles were used to correct aphakia after congenital cataract.

Results

Of the 49 patients, 20 patients with unilateral aphakia who used RGPCL were in group 1. Group 2 comprised 14 patients with persistent fetal vasculature (PFV) who used RGPCL, and there were 15 patients with spectacles in group 3. In group 1, there were important improvements in visual acuity, strabismus and nystagmus. In groups 2 and 3, there were no significant improvements in visual acuity, strabismus or nystagmus. Patients with a good adherence to patching had better visual acuity after the operation than patients who did not, in groups 1 and 3. There were no significant differences in myopic shift or rate of globe axial length growth among the 3 groups. No patients in group 1 had ocular disease that affected visual acuity. The mean annual expenses of the RGPCL group was 3965 yuan, and the mean annual cost of spectacles was 1140 yuan to 2500 yuan.

Conclusion

RGPCL is a safe and effective optical correction method for patients with monocular aphakia after congenital cataract surgery. Spectacles are not an ideal optical correction. Using RGPCL to correct patients with PFV, the final visual acuity improved, but the difference was not statistically significant. There were no improvements in strabismus or nystagmus in patients with PFV.

Long-term outcomes following primary intraocular lens implantation in infants younger than 6 months

Purpose:

To study the long-term safety profile and visual outcomes of primary intraocular lens (IOL) implantation in infants <6 months of age.

Methods:

This was a retrospective observational study conducted at a tertiary eye care center in South India. Infants under 6 months meeting the selection criteria who underwent cataract surgery (lens aspiration, primary posterior capsulorhexis, and anterior vitrectomy) with primary IOL implantation between January 2008 and December 2011 and minimum 3-year follow-up were included. Patient demographics, serial refractions, visual acuity, complications, and associated amblyopia/strabismus were reviewed. Visual acuity, myopic shift, and complications were the outcome measures.

Results:

Sixty-nine eyes of 38 infants (31 bilateral; mean age: 4.6 months) were reviewed. Mean follow-up was 51 months (range: 36–84). Median logMAR best-corrected visual acuity at the final visit was 0.74 (interquartile range [IQR]: 0.50–0.98) in eyes with bilateral cataracts and 0.87 (IQR: 0.60–1.14) in eyes with unilateral cataracts with an average myopic shift of 6.7 diopters over 4.2 years. Most common postoperative complication was visual axis opacification (VAO) (13 eyes, 18%), necessitating membranectomy followed by pigmentary IOL deposits (11 eyes, 15%), and IOL decentration and glaucoma in four eyes each (5.6%). Mixed linear effect model found no significant association of age, gender, laterality, and postoperative complications with final visual acuity (P ≥ 0.05). Eyes with unilateral cataracts had a greater myopic shift than bilateral cases (P = 0.03).

Conclusion:

Primary IOL implantation in infants <6 months is reasonably safe in appropriately selected infants. VAO was the most common postoperative complication, and a large myopic shift was observed.

Clinical features of strabismus and nystagmus in bilateral congenital cataracts

AIM

To evaluate the prevalence, clinical features, and the factors affecting onset of strabismus and nystagmus in patients with bilateral congenital cataracts.

METHODS

This study evaluated 116 eyes of 58 patients who underwent lens removal for the treatment of bilateral congenital cataracts between January 1999 and January 2011. The presence and type of strabismus and nystagmus were determined before and after surgery. Type of strabismus and final visual acuity were compared in patients with and without nystagmus. Patients were divided into three groups (orthotropia/orthotropia, orthotropia/strabismus, and strabismus/strabismus) according to their preoperative and postoperative ocular alignment. Age at cataract surgery and associations of nystagmus and primary intraocular lens (IOL) implantation with strabismus were analyzed.

RESULTS

Six patients (10.3%) had strabismus preoperatively and an additional 11 (19.0%) developed postoperative strabismus. Exotropia was more common than esotropia both preoperatively and postoperatively. Eighteen patients (31.0%) had postoperative nystagmus, with sensory nystagmus being the most common type. Of the 18 patients with nystagmus, 10 had strabismus, with exotropia being more common than esotropia. Postoperative visual acuity was poor in patients with nystagmus. Age at cataract surgery and rate of primary IOL implantation were significantly lower, and postoperative nystagmus was more common, in the orthotropia/strabismus group than in the other two groups.

CONCLUSION

Exotropia and sensory nystagmus are common in patients with bilateral congenital cataracts. Age at cataract surgery and rate of IOL implantation are lower and nystagmus more common in patients with postoperative onset of strabismus. Nystagmus is associated with poor visual prognosis.

[Impact of timing of surgery on outcome in children with bilateral congenital cataract]

BACKGROUND

The optimal time for surgical intervention in bilateral congenital cataract is still a matter of controversy.

OBJECTIVES

Herein, we evaluated clinical and functional results after bilateral congenital cataract surgery and performed subgroup analysis based on the age at the time of surgery.

MATERIALS AND METHODS

We retrospectively reviewed the records of 52 eyes of 26 children who underwent surgery for bilateral congenital cataract without intraocular lens implantation within the first 12 months of life; 16 eyes underwent phacoaspiration within the first 10 weeks of life (group A) and 26 eyes had cataract extraction at an age of >10 weeks (group B). We defined the primary outcome measure to be the prevalence of mild, moderate, and severe amblyopia in relationship to age-dependent visual acuity norms after a mean follow-up of 59.7 ± 43.2 months. Secondary outcome measures were interocular difference of visual acuity and the presence of strabismus, nystagmus, posterior capsule opacification, and aphakic glaucoma.

RESULTS

The prevalence of amblyopia was not statistically different between the two age groups. Of all children, 62.5 % (A) and 61.1 % (B) developed age-dependent normal visual acuity or mild amblyopia. However, the younger cohort developed significantly less strabismus than the older cohort (P = 0.03). There was a strong relationship between cataract surgery within the first 14 weeks of life and the development of aphakic glaucoma. All children developing secondary cataract formation underwent cataract surgery in the first 20 weeks of life.

CONCLUSIONS

Our results suggest that long-term prevalence of mild, moderate, and severe amblyopia is similar between the two cohorts of bilateral congenital cataract eyes based on the age ≤ or >10 weeks at the time of surgery. Because there is a strong relationship between postoperative complications and a young age at the time of cataract surgery, close postoperative follow-up is essential. Strabismus is less likely to develop in infants after bilateral cataract surgery within the first 10 weeks of life.

Strabismus surgery outcomes in the Infant Aphakia Treatment Study (IATS) at age 5 years

PURPOSE

To report strabismus surgery frequency and outcomes after monocular infantile cataract surgery with or without IOL implantation.

METHODS

The Infant Aphakia Treatment Study (IATS) is a randomized, multicenter clinical trial comparing treatment of aphakia with a primary IOL or contact lens in 114 infants with a unilateral congenital cataract. This report is a secondary outcome analysis of ocular motor data from IATS patients who underwent strabismus surgery prior to age 5 years.

RESULTS

Strabismus surgery was performed in 45 (39%) patients (contact lens group [CL], 37%; IOL group, 42% [P = 0.70]). The indications for strabismus surgery were esotropia (62%), exotropia (33%), and hypertropia (4%). Infants who underwent cataract surgery at a younger age were less likely to undergo strabismus surgery (28-48 days, 12/50 [24%]; 49-210 days, 33/64 [52%]; P = 0.0037). Of the 42 patients who underwent strabismus surgery, 14 (33%) had a postoperative distance alignment within 8^Δ of orthotropia at age 5 years. The 5-year visual acuity of children with strabismus was the same whether or not strabismus surgery had been performed (1.10 logMAR with surgery vs 1.00 without [P = 0.71]).

CONCLUSIONS

In this study cohort, cataract surgery performed in the first 6 weeks of life was associated with a reduced frequency of strabismus surgery. Strabismus surgery outcomes in this population are guarded. Surgical improvement of strabismus does not appear to influence long-term visual acuity.

Strabismus developing after unilateral and bilateral cataract surgery in children

PurposeTo evaluate the prevalence and risk factors of strabismus in children undergoing surgery for unilateral or bilateral cataract with or without intraocular lens implantation.MethodsMedical records of pediatric patients were evaluated from 2000 to 2011. Children undergoing surgery for unilateral or bilateral cataract with at least 1 year of follow-up were included. Children with ocular trauma, prematurity, or co-existing systemic disorders were excluded. The following data were evaluated: strabismus pre- and post-operation; age at surgery; post-operative aphakia or pseudophakia; and visual acuity.ResultsNinety patients were included, 40% had unilateral and 60% had bilateral cataracts. Follow-up was on average 51 months (range: 12-130 months). Strabismus was found preoperatively in 34.4% children, and in 43.3% children at last follow-up. Strabismus developed in 46.2% of children who were orthotropic preoperatively, whereas 32.3% of children who had strabismus before surgery became orthotropic. Strabismus occurred after unilateral or bilateral cataract surgery in 63.9% and 29.6% children, respectively. At the last follow-up, strabismus was found in 46.7% of aphakic and 58.7% of pseudophakic children (P=0.283). Children who developed strabismus were generally operated at a younger age as compared with those without strabismus (mean of 25.9 vs 52.7 months, P<0.001). Final visual acuity was inversely correlated with prevalence of strabismus.ConclusionStrabismus is a frequent complication after cataract surgery in children. Risk factors include unilateral cases and young age at surgery. No correlation was found between prevalence of strabismus and use of intraocular lens. Strabismus was more common in children with poor final visual acuity.

Congenital and Developmental Cataracts: Focus on Strabismus Outcomes at Long-Term Follow-Up

PURPOSE

To evaluate the incidence of strabismus in congenital and developmental cataract surgery in patients with a follow-up longer than five years.

METHODS

All patients with congenital and developmental cataracts observed from 1996 to 2013 with a follow-up longer than five years were retrospectively included.

RESULTS

We included 117 patients (58 females and 59 males, mean age 0.62±0.3 years, 160 eyes) with congenital cataracts and 73 patients (32 females and 41 males, mean age 6.63±0.7 years, 121 eyes) with developmental cataracts. Before cataract surgery, strabismus was present in 88 patients with congenital cataracts (75.2%) and in 30 patients with developmental cataracts (41.1%) (p=0.01). After a follow-up of 9.26±1.3 years (range, 5-14 years), a significantly greater incidence of strabismus was observed after surgery only in patients with unilateral congenital cataracts who underwent cataract removal and primary IOL implantation (p=0.02). Distance BCVA and near BCVA were better after surgery for developmental cataracts (p<0.05). Presence of binocular vision was more frequent after surgery for developmental cataracts (p=0.001).

CONCLUSION

Incidence of strabismus and postsurgical onset of strabismus at long-term follow-up was greater in patients with congenital cataracts.

Lens regeneration using endogenous stem cells with gain of visual function

The repair and regeneration of tissues using endogenous stem cells represents an ultimate goal in regenerative medicine. To our knowledge, human lens regeneration has not yet been demonstrated. Currently, the only treatment for cataracts, the leading cause of blindness worldwide, is to extract the cataractous lens and implant an artificial intraocular lens. However, this procedure poses notable risks of complications. Here we isolate lens epithelial stem/progenitor cells (LECs) in mammals and show that Pax6 and Bmi1 are required for LEC renewal. We design a surgical method of cataract removal that preserves endogenous LECs and achieves functional lens regeneration in rabbits and macaques, as well as in human infants with cataracts. Our method differs conceptually from current practice, as it preserves endogenous LECs and their natural environment maximally, and regenerates lenses with visual function. Our approach demonstrates a novel treatment strategy for cataracts and provides a new paradigm for tissue regeneration using endogenous stem cells.

Primary versus secondary IOL implantation following removal of infantile unilateral congenital cataract: outcomes after at least 5 years

PURPOSE

To report outcomes after at least 5 years' follow-up of consecutive patients at a single center undergoing unilateral congenital cataract surgery during infancy with primary intraocular lens (IOL) implantation at the time of surgery or undergoing secondary IOL implantation later in childhood.

METHODS

The medical records of pseudophakic children who received initial cataract surgery before 7 months of age were retrospectively reviewed. Children with acquired cataract, persistent fetal vasculature, congenital glaucoma, or follow-up of <5 years were excluded.

RESULTS

Mean age at time of cataract surgery was 2.7 months in the primary group (n = 13) and 1.9 months in the secondary group (n = 13). Mean age at IOL implantation in the latter group was 4.9 ± 2.2 years. Mean age at final follow-up was 10.7 ± 4.2 years in the primary group and 8.7 ± 3.0 years in the secondary group. Glaucoma surgery was performed in 2 primary group eyes and 1 secondary group eye; it was medically controlled in 2 additional eyes of the latter group. One secondary group eye was diagnosed as glaucoma suspect. Visual axis opacification required surgery in 5 primary group eyes and 2 secondary group eyes before IOL implantation. Unplanned IOL exchange or removal for high myopia was required in 3 primary group eyes and 1 secondary group eye. Strabismus surgery was performed in 3 primary group eyes and 7 secondary group eyes. Median visual acuity at final follow-up was 20/150 in both groups. Refraction at last follow-up was -2.9 ± 3.3 D in the primary and -1.8 ± 2.5 D in the secondary group.

CONCLUSIONS

Reoperations were common in both groups over long-term follow-up. Close monitoring for glaucoma is also needed in both groups.

Sensorimotor outcomes by age 5 years after monocular cataract surgery in the Infant Aphakia Treatment Study (IATS)

PURPOSE

To evaluate sensorimotor outcomes among children in the Infant Aphakia Treatment Study (IATS).

METHODS

Secondary outcome analysis was performed in this randomized, multicenter, clinical trial comparing treatment of unilateral aphakia with a primary intraocular lens (IOL) or contact lens (CL) correction. The alignment characteristics and sensory status of children through age 5 years were evaluated.

RESULTS

In the IATS study, 91 of 112 children (81%) developed strabismus through age 5 years. Of 34 infants who were orthotropic at near 12 months after cataract surgery, at age 5 years 14 (41%) were orthotropic at distance, and 15 (44%) were orthotropic at near at age 5 years without strabismus surgery. Eight of 56 children (14%) in the CL group and 13 of 56 (23%) in the IOL group were orthotropic at distance (P = 0.33) at 5 years of age and had no history of strabismus surgery. Thirteen of 48 (27%) who underwent cataract surgery prior to 49 days of age compared to 8 of 64 (13%) who had surgery after 49 days were orthotropic (P = 0.085). Median visual acuity in the operative eye was 0.4 logMAR (20/50) for children with orthotropia or microtropia (<10(Δ)) versus 1.10 logMAR (20/252) for strabismus ≥10(Δ) (P = 0.0001). Stereopsis was detected in 12 of 21 children (57%) with orthotropia versus 16 of 89 (18%) children with strabismus (P = 0.0006).

CONCLUSIONS

IOL placement does not reduce the development of strabismus after monocular congenital cataract surgery. Improved ocular alignment by age 5 years correlated strongly with improved visual acuity and stereopsis.

Long-Term Visual Outcomes of Secondary Intraocular Lens Implantation in Children with Congenital Cataracts

Aim

The aim of this study was to evaluate the long-term visual outcomes and factors affecting visual results in children undergoing secondary intraocular lens (IOL) implantation following primary congenital cataract extraction.

Methods

Children with congenital cataracts who underwent secondary IOL implantation for aphakia at the Eye and ENT Hospital of Fudan University between January 1, 2001, and December 31, 2007, were retrospectively reviewed. One eye was randomly selected in children with bilateral cataracts. Laterality, type of cataract (total or partial opacity), sex, age at primary and secondary surgeries, visual axis opacity (VAO), compliance with amblyopia therapy, postoperative ocular complications, refractive error, ocular alignment, and best corrected visual acuity (BCVA) at last follow-up were recorded; potential factors that might have affected the visual results were evaluated.

Results

Seventy-six bilateral and 34 unilateral congenital cataract cases were analyzed; the mean ages of the children were 12.70±5.06 and 12.50±2.71 years at final follow-up, the mean follow-up periods from IOL implantation were 94.93±24.22 and 109.09±18.89 months, and the mean BCVA (Log MAR) values were 0.51±0.37 and 1.05±0.46, respectively. Final BCVA after secondary IOL implantation was significantly associated with laterality, type of cataract, age at primary cataract extraction, compliance with amblyopia therapy, and refractive correction after surgery. No significant associations were found between BCVA and sex, age at secondary IOL implantation, VAO, or other ocular complications. The most common ocular complications were VAO and elevated intraocular pressure after surgery. There were no other complications, with the exception of one eye with IOL dislocation.

Conclusions

The results indicate that the important determinants of long-term visual outcomes in children with congenital cataracts undergoing secondary IOL implantation are laterality, cataract type, age at initial cataract extraction, compliance with amblyopia therapy, and refractive error.

Complications of pediatric cataract surgery

PURPOSE

Cataract surgery in young children poses different challenges and potential complications compared to those encountered in adult populations. We performed a literature review of the complications of pediatric cataract surgery.

METHODS

Literature review of complications of pediatric cataract surgery.

RESULTS

Complications in children vary based on the age of the patient at surgery and the cause of the cataract. Common events discussed include increased inflammatory response, opacification of the posterior capsule, lens reproliferation, pupillary membrane, and amblyopia; less common events include infections, significant bleeding, and retinal detachment.

CONCLUSION

Complications after cataract surgery in children are often associated with a robust inflammatory reaction or secondary opacity and, in infants, glaucoma. Late complications can occur decades later, so that long-term follow-up is required. Though surgery carries significant risks, the consequences of no surgery and irreversible deprivation amblyopia in very young children should be considered.

Strabismus in infants following congenital cataract surgery

PURPOSE

This study aimed to determine the incidence and characteristics of strabismus following congenital cataract surgery in infants.

MATERIALS AND METHODS

Patients aged <12 months who underwent surgery for congenital cataract and were followed-up for ≥1 years were included. Patients that had strabismus prior to surgery were excluded. Data regarding gender, cataract laterality, morphology, and density, age at the time of cataract surgery, ocular motility post surgery, and the presence of nystagmus were retrospectively obtained from the patients' records.

RESULTS

The study included 79 patients (48 male and 31 female). Unilateral surgery was performed in 14 of the patients, versus bilateral surgery in 65. Strabismus did not occur post surgery in 32 (40.5 %) of the patients (group 1), whereas 47 (59.5 %) (group 2) developed strabismus following surgery. The patients in group 1 were followed-up for a mean 50.7 ± 38.5 months, versus 50.3 ± 39 months in group 2. Mean age at the time of cataract surgery in groups 1 and 2 was 3.6 ± 1.9 years and 4.6 ± 3.2 months respectively. Mean duration of time between cataract surgery and the development of strabismus was 13.3 ± 13 months (range: 1-60 months). Unilateral cases were more prone to develop strabismus, which was statistically significant (p = 0.028). Age at the time of cataract surgery, gender, cataract density, the occurrence of aphakic glaucoma, the presence of nystagmus, and additional ocular surgery were not significantly associated with the development of strabismus.

CONCLUSION

Strabismus develops more frequently in children undergoing cataract surgery. In the present study strabismus occurred in more of the patients that underwent unilateral surgery. Based on the present findings, we think that long-term careful follow-up to monitor the development of strabismus is required in all infants undergoing cataract surgery, especially unilateral cases.

Comparison of contact lens and intraocular lens correction of monocular aphakia during infancy: a randomized clinical trial of HOTV optotype acuity at age 4.5 years and clinical findings at age 5 years

IMPORTANCE

The efficacy and safety of primary intraocular lens (IOL) implantation during early infancy is unknown.

OBJECTIVE

To compare the visual outcomes of patients optically corrected with contact lenses vs IOLs following unilateral cataract surgery during early infancy.

DESIGN, SETTING, AND PARTICIPANTS

The Infant Aphakia Treatment Study is a randomized clinical trial with 5 years of follow-up that involved 114 infants with unilateral congenital cataracts at 12 sites. A traveling examiner assessed visual acuity at age 4.5 years.

INTERVENTIONS

Cataract surgery with or without primary IOL implantation. Contact lenses were used to correct aphakia in patients who did not receive IOLs. Treatment was determined through random assignment.

MAIN OUTCOMES AND MEASURES

HOTV optotype visual acuity at 4.5 years of age.

RESULTS

The median logMAR visual acuity was not significantly different between the treated eyes in the 2 treatment groups (both, 0.90 [20/159]; P = .54). About 50% of treated eyes in both groups had visual acuity less than or equal to 20/200. Significantly more patients in the IOL group had at least 1 adverse event after cataract surgery (contact lens, 56%; IOL, 81%; P = .02). The most common adverse events in the IOL group were lens reproliferation into the visual axis, pupillary membranes, and corectopia. Glaucoma/glaucoma suspect occurred in 35% of treated eyes in the contact lens group vs 28% of eyes in the IOL group (P = .55). Since the initial cataract surgery, significantly more patients in the IOL group have had at least 1 additional intraocular surgery (contact lens, 21%; IOL, 72%; P < .001).

CONCLUSIONS AND RELEVANCE

There was no significant difference between the median visual acuity of operated eyes in children who underwent primary IOL implantation and those left aphakic. However, there were significantly more adverse events and additional intraoperative procedures in the IOL group. When operating on an infant younger than 7 months of age with a unilateral cataract, we recommend leaving the eye aphakic and focusing the eye with a contact lens. Primary IOL implantation should be reserved for those infants where, in the opinion of the surgeon, the cost and handling of a contact lens would be so burdensome as to result in significant periods of uncorrected aphakia.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00212134

Factors associated with strabismus after cataract extraction and primary intraocular lens implantation in congenital cataracts

AIM

To evaluate factors associated with the development of strabismus after cataract extraction and primary intraocular lens implantation.

METHODS

The medical records of 122 patients, aged 1.5mo to 9y, who had undergone cataract extraction with primary intraocular lens implantation between January 1993 and August 2011 were reviewed. Fourteen patients (17 eyes) with strabismus before cataract surgery were excluded. Patients were divided into those with congenital bilateral cataracts (64 patients, 128 eyes) and those with unilateral cataracts (44 patients, 44 eyes). The associations between the development of strabismus and age at cataract surgery, pre- and post-cataract extraction corrected distance visual acuity (CDVA), interocular CDVA difference, nystagmus, surgical method, and secondary cataract were evaluated.

RESULTS

Factors significantly associated with the development of strabismus included age at cataract surgery (≤1y), preoperative mean CDVA ≤20/100, presence of nystagmus in the bilateral cataract group and postoperative interocular CDVA difference >20/70 in the unilateral group. Postoperative CDVA ≤20/100 and preservation of posterior capsule, and presence of secondary cataract were significant factors in both groups.

CONCLUSION

Children with congenital cataracts should be monitored carefully after cataract surgery for the development of strabismus, especially when they underwent surgery at age ≤1y, and they have nystagmus, large postoperative interocular CDVA difference, poor preoperative and postoperative CDVA, preservation of the posterior capsule, or secondary cataract.