Refractive surgery for high bilateral myopia in children with neurobehavioral disorders: 1. Clear lens extraction and refractive lens exchange

Pediatric refractive surgery: Review article

Refractive surgery is one of the most commonly performed elective procedures in ophthalmology; it is mostly performed in patients who are older than 18 years of age. This routine procedure has been time-tested and is proven to be both safe and effective in adults. However, little is known about the safety and efficacy of refractive surgery in pediatric patients. Granted, refractive surgery should not be used in kids merely for the purpose of avoiding spectacles wear, but it can be of valuable help is preserving vision in patients with amblyopia and accommodative esotropia who otherwise couldn't comply with traditional management options. Refractive surgery in pediatric patients is a complex and challenging field due to the unique characteristics of their developing eyes. This review article aims to provide an overview of the current literature on refractive surgery in pediatric patients, focusing on the different surgical options, the advantages and disadvantages of each procedure.

Refractive Lens Exchange: A Review

In recent decades, technical advancements in lens surgery have considerably improved safety and refractive outcomes. This has led to a much broader range of indications for refractive lens exchange (RLE). Effective restoration of uncorrected distance and near visual acuity is possible with modern presbyopia correcting intraocular lenses (IOLs). Hyperopic patients who are fully presbyopic were identified as ideal candidates for RLE. For myopic patients, an increased risk of retinal detachment has been reported, which leads to a higher threshold to perform RLE in this patient group. The most frequent postoperative complications include posterior capsular opacification, deviation from the target refraction and cystoid macular edema. Thus, adequate planning of surgery, careful patient selection, as well as comprehensive counseling are crucial for successful RLE.

Refractive Surgery in Myopic Children

In this paper, we summarize the current knowledge on refractive surgery performed in the myopic pediatric population. We describe the main concerns about refractive surgery in myopic children and the indications for refractive surgery in this age group. We present a range of surgical procedures that are being used for the management of unilateral/bilateral myopia in children: corneal refractive surgery (PRK, LASEK, LASIK, FS-LASIK and SMILE) and intraocular refractive surgery (phakic intraocular lens implantation, refractive lens exchange or clear lens extraction), with both their advantages and drawbacks. We also describe the various complications and measures to prevent them.

Refractive surgeries in children: Debunking the controversy and assessing the safety and efficacy

New innovations in adults' refractive surgeries have revolutionized the field, offering improved outcomes and enhanced patient experiences. While traditionally considered contraindicated in pediatric populations, emerging research suggests that this notion may not always hold true. Challenges, indications, safety, and other topics will be addressed in this review article.

Techniques in pediatric refractive surgery

Pediatric refractive surgery treats refractive errors and their associated comorbidities such as amblyopia and strabismus in special needs children intolerant of spectacles or contact lenses. Children with neurobehavioral disorders undergoing refractive surgery have improvements in visual acuity, communication, socialization, motor skills, adaptive behaviors, visual perception, and cognitive function. Contrary to adults, amblyopia is frequently an indication for refractive surgery in special needs children. Pediatric refractive surgery techniques modify ametropia at the corneal, anterior chamber, posterior chamber, and lens planes. This article will discuss the most common modalities used today in pediatric refractive surgery, including laser keratorefractive surgery, phakic intraocular lenses, and refractive lens exchange. Practical pearls are discussed for the implementation of pediatric refractive surgery, reviewing preoperative diagnostics, surgical techniques, and postoperative care.

Clear lens extraction and refractive lens exchange for the treatment of amblyopia

Treatment of amblyopia typically involves spectacles or penalization of the nonamblyopic eye with occlusive patching or pharmacological penalization. However, these methods can be ineffective or difficult in certain children who may be unable to tolerate or are poorly compliant with such therapies. Untreated high refractive error can result in dense amblyopia, and thus, other treatment methods are necessary in this subset of children. With technological advances in ocular surgery, clear lens extraction (CLE) and refractive lens exchange (RLE) have emerged as popular alternative treatments for amblyopia, as they may avoid some of the challenges surrounding traditional methods. CLE involves lensectomy for refractive purposes in patients without cataracts, while RLE involves lensectomy followed by intraocular lens implantation. The purpose of this review was to summarize the use of CLE and RLE for the treatment of amblyopia in the pediatric population, discussing indications, techniques, treatment outcomes, safety, and potential complications.

Screening Mutations of the Monogenic Syndromic High Myopia by Whole Exome Sequencing From MAGIC Project

Purpose

This observational study aimed to identify mutations in monogenic syndromic high myopia (msHM) using data from reported samples (n = 9370) of the Myopia Associated Genetics and Intervention Consortium (MAGIC) project.

Methods

The targeted panel containing 298 msHM-related genes was constructed and screening of clinically actionable variants was performed based on whole exome sequencing. Capillary sequencing was used to verify the identified gene mutations in the probands and perform segregation analysis with their relatives.

Results

A total of 381 candidate variants in 84 genes and 85 eye diseases were found to contribute to msHM in 3.6% (335/9370) of patients with HM. Among them, the 22 genes with the most variations accounted for 62.7% of the diagnostic cases. In the genotype-phenotype association analysis, 60% (201/335) of suspected msHM cases were recalled and 25 patients (12.4%) received a definitive genetic diagnosis. Pathogenic variants were distributed in 18 msHM-related diseases, mainly involving retinal dystrophy genes (e.g. TRPM1, CACNA1F, and FZD4), connective tissue disease genes (e.g. FBN1 and COL2A1), corneal or lens development genes (HSF4, GJA8, and MIP), and other genes (TEK). The msHM gene mutation types were allocated to four categories: nonsense mutations (36%), missense mutations (36%), frameshift mutations (20%), and splice site mutations (8%).

Conclusions

This study highlights the importance of thorough molecular subtyping of msHM to provide appropriate genetic counselling and multispecialty care for children and adolescents with HM.

IMI-Management and Investigation of High Myopia in Infants and Young Children

Purpose

The purpose of this study was to evaluate the epidemiology, etiology, clinical assessment, investigation, management, and visual consequences of high myopia (≤-6 diopters [D]) in infants and young children.

Findings

High myopia is rare in pre-school children with a prevalence less than 1%. The etiology of myopia in such children is different than in older children, with a high rate of secondary myopia associated with prematurity or genetic causes. The priority following the diagnosis of high myopia in childhood is to determine whether there is an associated medical diagnosis that may be of greater overall importance to the health of the child through a clinical evaluation that targets the commonest features associated with syndromic forms of myopia. Biometric evaluation (including axial length and corneal curvature) is important to distinguishing axial myopia from refractive myopia associated with abnormal development of the anterior segment. Additional investigation includes ocular imaging, electrophysiological tests, genetic testing, and involvement of pediatricians and clinical geneticists is often warranted. Following investigation, optical correction is essential, but this may be more challenging and complex than in older children. Application of myopia control interventions in this group of children requires a case-by-case approach due to the lack of evidence of efficacy and clinical heterogeneity of high myopia in young children.

Conclusions

High myopia in infants and young children is a rare condition with a different pattern of etiology to that seen in older children. The clinical management of such children, in terms of investigation, optical correction, and use of myopia control treatments, is a complex and often multidisciplinary process.

Visual Autism

Autism spectrum disorder (ASD) is a lifelong neurodevelopmental disorder characterized by deficits in social communication and restricted, repetitive behaviors. It affects approximately 2.2% of children. Both genetic and environmental risk factors have been identified for ASD. Visual comorbidities are relatively common among children with ASD. Between 20 and 44% of ASD children have visually significant refractive error, on-third have strabismus, and one-fifth have amblyopia. In addition, ASD is 30 times more common in children with congenital blindness. It is unknown whether the association of ASD with visual morbidity is causal, comorbid, or contributing. Structural and functional abnormalities have been identified in MRIs of ASD children, and ASD children have been noted to have aberrant eye tracking. ASD children with visually significant refractive errors and poor spectacle compliance (present in 30% of ASD children) offer the opportunity for investigation into how improved visual acuity influences ASD behaviors. In this review, we focus on what is known of the visual system, refractive surgery, and ASD.

Impact of Ocular Conditions and Improvements After Refractive Surgery in Quality of Life for Children With Neurodevelopmental Disorders

PURPOSE

This study aims to characterize the eye-related quality of life of children with neurodevelopmental and ocular disorders at baseline and after refractive surgery.

DESIGN

Prospective interventional case series.

METHODS

We enrolled children and adolescents 5 to 18 of age with neurodevelopmental disorders undergoing refractive surgery (6 for pre-/postsurgical assessment and 14 for baseline analysis). Eye-related quality of life was measured using the Pediatric Eye Questionnaire (PedEyeQ). Baseline levels of adaptive functioning and social behaviors were measured using the Adaptive Behavioral Assessment System (ABAS-3) and Social Responsiveness Scale (SRS-2). We assessed the correlation between baseline PedEyeQ scores, number of ocular comorbidities, magnitude of refractive error, and ABAS-3 and SRS-2 scores.

RESULTS

At baseline, 14 patients demonstrated decreased median eye-related quality of life (<60/100) in 5 of 9 PedEyeQ domains, moderate deficiencies in social behaviors (SRS-2 median 71, range 49-90), and low adaptive functioning (ABAS-3 median percentile for age of 0.100). Baseline PedEyeQ scores did not correlate with magnitude of refractive error or adaptive functioning scores but did correlate with number of ocular comorbidities and social behavior scores. Six patients have undergone refractive surgery without complication. Postoperatively, 11 of 11 eyes were within ±1.5 diopters spherical equivalent. Four of 6 patients exhibited clinically significant improvements in PedEyeQ scores after surgery.

CONCLUSIONS

Even in the presence of significant social and adaptive impairments, quality of life in children with neurodevelopmental disorders is decreased by ocular disorders. Refractive surgery is associated with clinically significant improvements in eye-related quality of life.

Ten-Year Outcomes of LASIK for Pediatric Myopic Anisometropia

Purpose

To evaluate long-term safety, effectiveness, and stability of unilateral LASIK in pediatric myopic anisometropic amblyopia.

Methods

This retrospective study included children who received unilateral LASIK for myopic anisometropia of >6 D, after mandatory 6-month occlusion/penalization therapy. They were evaluated at 6 months, 1 year, 2 years and biannually until 10 years. Outcome measures included visual acuity, refraction, ocular alignment, stereopsis, corneal clarity, and corneal topography.

Results

32 patients (16 girls) with mean age of 8.6 ± 2.3 years completed 10 years of follow up after unilateral LASIK. Mean preoperative spherical equivalent refraction (SER) was -10.3D ±2.0D in the affected eye, with anisometropic difference of -9.5D ±1.7D. Mean post-LASIK SER was -1.3D±0.8D (p<0.001). Anisometropia significantly decreased to 0.3D±0.8D, 0.4D±1.0D, and 1.0±2.5D at 6 months, 1 year and 10 years respectively (p<0.001). 11 patients (34%) who had preoperative intermittent exotropia (< 15°) regained orthophoria in all gazes, while 5 of 10 who had constant exotropia with large angle (>30°) required strabismus surgery for ocular alignment. BCVA improved from 0.04±0.6 Decimal at baseline to 0.6 ±0.2 after LASIK and occlusion therapy (p< 0.001). Despite insignificant refractive regression in both eyes, patients have maintained orthophoria, improved stereopsis, clear cornea, and the topography showed no evidence of post-LASIK ectasia.

Conclusion

LASIK appears safe, effective, and stable for correcting refractory pediatric myopic anisometropia, in which conventional measures fail or endanger normal visual development. Eliminating anisometropic aniseikonia consequently restores binocular vision and stereopsis which, along with amblyopia therapy, would reverse amblyopia and prevent recurrence.

Refractive Lens Exchange Surgery in Early-Onset High Myopia Patients With Partial Cataract

Purpose

By reporting clinical characteristics and retinal image quality before and after refractive lens replacement surgery in early-onset high myopia (eoHM) patients presenting with partial cataract, we emphasized the need for an objective way to grade the severity of partial cataracts.

Methods

This retrospective, consecutive case series included six Chinese patients (nine eyes). Analysis of previous medical records, visual acuity, optometry, retinal image quality, and axial length (AXL) before surgery and after surgery was performed.

Results

Five females and one male (nine eyes) with a mean (± SD) age of 11.6 ± 7.9 years (range: 4–25 years) were included in this study. The preoperative spherical power ranged from −7.5 to −42 D. The mean follow-up time was 36 months (range: 24–48 months). Phacoemulsification was followed by in-the-bag implantation of intraocular lens. For patients who were under 6 years old, posterior capsulotomy + anterior vitrectomy were performed simultaneously. All surgeries were uneventful and no postoperative complications occurred during the entire follow-up period. All patients’ uncorrected visual acuity improved by ≥2 lines postoperatively(Snellen acuity). LogMAR best-corrected visual acuity was improved at 24-month (P = 0.042) and endpoint (P = 0.046) follow-ups. Modulation transfer function cutoff frequency (MTF_cutoff) and objective scatter index (OSI) was significantly improved at 12-month (P = 0.025, P = 0.038), 24-month (P = 0.005, P = 0.007) and endpoint (P = 0.005, P = 0.008) follow-ups. Postoperative AXL remained stable during 2–4 year follow-ups (P > 0.05).

Conclusion

Refractive lens replacement surgery is safe and effective for improving functional vision in eoHM patients presenting with partial cataract. Retinal image quality could provide a useful and objective way to facilitate partial cataract severity evaluation and surgery decision making.

Developmental Improvement in Children With Intellectual Disability After Photorefractive Keratectomy for Severe Isoametropia

PURPOSE

To assess the impact of refractive error correction from photorefractive keratectomy on development in children with severe isoametropia, subnormal visual acuity, and intellectual disability unable to use refraction correction.

DESIGN

Prospective noncomparative interventional case series.

METHODS

Before and after photorefractive keratometry (PRK), subjects who had plateaued developmentally for 18 or more months were assessed using a battery of developmental tests. The primary outcome measure was the change in the developmental quotient (DQ) 6 months after PRK. Secondary outcomes were the change in the DQ, uncorrected visual acuity, cycloplegic refraction, and corneal status 12, 24, and 36 months after PRK.

RESULTS

Sixteen subjects aged 2 to 8 years were included. Twelve were highly myopic (mean, -9.69 ± 3.82 diopters [D]), 3 highly hyperopic (mean, +5.75 ± 0.59 D) and 1 highly astigmatic (mean, +3.50 D). Six months after PRK, the DQ significantly improved for expressive communication (mean, 4.51 ± 2.27 months; P = .04), interpersonal relationships (mean, 9.45 ± 4.18 months; P = .02) and coping (mean, 6.44 ± 2.10 months; P = .05). Twelve months after PRK, the DQ significantly improved for receptive communication (8.04 ± 1.80 months; P < .001), expressive communication (6.99 ± 2.27 months; P < .05), written communication (9.28 ± 3.72 months; P < .04), domestic skills (6.50 ± 2.43 months; P < .03), interpersonal relationships (10.57 ± 4.17 months; P < .02), and coping (8.41 ± 3.25 months; P < .5).

CONCLUSIONS

PRK significantly improves developmental abilities of children with intellectual disability, severe isoametropia, and previously plateaued development, in addition to improving visual acuity and refractive error.

Safety of phakic intraocular collamer lens implantation in 95 highly myopic special-needs children

PURPOSE

To assess the safety of intraocular collamer lens (ICL) implantation in children with high ametropia by reporting rates and case specifics of perioperative and longer-term adverse events (AEs).
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SETTING

St. Louis Children's Hospital at Washington University Medical Center, St. Louis, Missouri.

DESIGN

Retrospective case series.

METHODS

Clinical data were collated retrospectively for 95 special-needs children (160 eyes) implanted with a Visian ICL over the past 5 years. All surgeries were performed at St Louis Children's Hospital under brief general anesthesia. The mean follow-up period was 2.0 ± 1.4 years (range, 0.5 to 5.2).

RESULTS

The mean age at implantation was 9.3 ± 5.2 years (range, 1.8 to 25) and mean preoperative spherical equivalent refractive error was -11.20 ± 3.90 diopters (range, 4 to 22). 62 children (62/95, 65%) had a neurodevelopmental disorder. 3 eyes (3/160, 2%) reported minor AE, consisting of steroid-response ocular hypertension, which resolved with cessation of topical steroid drops. Endothelial cell loss averaged 8.1% over 2 years, comparable with that reported in ICL-implanted adults. The most common major AE (7 eyes [7/160, 4%]) was postoperative pupillary block, requiring revision of the peripheral iridotomy. 1 child (1 eye [1/160, 0.6%]) with self-injurious behavior required repair of a wound leak. 1 child (1 eye [1/160, 0.6%]) with Down syndrome developed a cataract 2.8 years after ICL surgery, and 1 child (1 eye [1/160, 0.6%]) with severe autism spectrum disorder experienced traumatic retinal detachment 1.2 years after implantation.

CONCLUSIONS

The most common major AE among the cohort with Visian ICL was pupillary block due to closure of the iridotomy. Overall, the AE rate was low in this higher risk, difficult-to-manage population of special-needs children.

[Refractive surgery for children with developmental delay : Indications, techniques and results]

Visual stimulation and communication with the surroundings are crucial factors for childhood development. In children with intellectual disability the developmental delay can be exacerbated by visual impairment leading to visual autism. Uncorrected refractive error is one of the leading causes of visual impairment and spectacles are the gold standard for treatment. For some children with developmental delay or intellectual disability, the fitting and wearing of spectacles can be impossible due to severe craniofacial malformations, poor neck control or involuntary head movements. In these cases, if wearing contact lenses is also impossible the refractive error remains untreated and the child visually impaired. In certain situations cornea-based laser refractive surgery or lens-based refractive surgery can treat these refractive errors to enable better unaided visual acuity and therefore enhanced stimulation and integration of these developmentally delayed children. This article describes and discusses the indications, technical aspects and results of refractive surgery for children with developmental delay and intellectual disability.

New advances in amblyopia therapy II:

The treatment of anisometropic or ametropic amblyopia has traditionally enjoyed a high treatment success rate. Early initiation and consistent use of spectacle correction can completely resolve amblyopia in a majority of patients. For those with anisometropic amblyopia that fail to improve with glasses wear alone, patching or atropine penalisation can lead to equalisation of visual acuity. However, successful treatment requires full-time compliance with refractive correction and this can be a challenge for a patient population that often has one eye with good acuity without correction. Other barriers for a select population with high anisometropic  or ametropic amblyopia include rejection of glasses for various reasons including discomfort, behavioural or sensory problems, postural issues and visually significant aniseikonia. When consistent wear of optical correction proves difficult and patching/atropine remains a major obstacle, surgical correction of refractive error has proven success in achieving vision improvement. Acting as a means to achieve spectacle independence or reducing the overall needed refractive correction, refractive surgery can offer a unique treatment option for this patient population. Laser surgery, phakic intraocular lenses and clear lens exchange are three approaches to altering the refractive state of the eye. Each has documented success in improving vision, particularly in populations where glasses wear has not been possible. Surgical correction of refractive error has a risk profile greater than that of more traditional therapies. However, its use in a specific population offers the opportunity for improving visual acuity in children who otherwise have poor outcomes with glasses and patching/atropine alone.

Phakic Intraocular Collamer Lens (Visian ICL) Implantation for Correction of Myopia in Spectacle-Aversive Special Needs Children

PURPOSE

A subset of children with high anisometropia or isoametropia and neurobehavioral disorders have chronic difficulties with spectacle or contact lens wear. We report the results of refractive surgery in a series of these children treated using bilateral or unilateral intraocular collamer lens (Visian ICL) implantation for moderate to high myopia.

DESIGN

Prospective nonrandomized cohort study.

METHODS

Clinical course and outcome data were collated prospectively for 40 implanted eyes in 23 children (mean age 10.2 ± 5.3 years, range, 1.8-17 years). Myopia ranged from -3.0 to -14.5 diopters (D), mean -9.2 ± 3.5 D. Goal refraction was plano to +1 D. Correction was achieved by sulcus implantation of a Visian ICL (STAAR Surgical, Monrovia, California, USA) under general anesthesia. Mean follow-up was 15.1 months (range, 6-22 months).

RESULTS

Thirty-five eyes (88%) were corrected to within ±1.0 D of goal refraction; the other 5 (12%) were corrected to within 1.5 D. Uncorrected distance visual acuity improved substantially in all eyes (from mean 20/1050 [logMAR 1.72] to mean 20/42 [logMAR 0.48]). Spherical regression at last follow-up was an average of +0.59 D. Visuomotor comorbidities (eg, amblyopia, nystagmus, foveopathy, optic neuropathy) accounted for residual postoperative subnormal visual acuity. Thirteen of the 23 children (57%) had a neurobehavioral disorder (eg, developmental delay/intellectual disability/mental retardation, Down syndrome, cerebral palsy, autism spectrum disorder). Eighty-five percent (11/13) of those children were reported to have enhanced visual awareness, attentiveness, or social interactions. Endothelial cell density was measureable in 6 cooperative children (10 eyes), showing an average 1% decline. Central corneal thickness, measured in all children, increased an average of 8 μm. Two children (8%) required unplanned return to the operating room on the first postoperative day to alleviate pupillary block caused by a nonpatent iridotomy. No other complications were encounterd.

CONCLUSION

Visian ICL implantation improves visual function in special needs children who have moderate to high myopia and difficulties wearing glasses or contact lenses.

Modern Phacoemulsification and Intraocular Lens Implantation (Refractive Lens Exchange) Is Safe and Effective in Treating High Myopia

Improved efficacy, predictability, and safety of modern phacoemulsification have resulted in cataract surgery being considered as a refractive procedure. Refractive lens exchange by definition is a surgery aimed at replacing the cataractous or clear crystalline lens with an intraocular lens (IOL) in cases of high ametropia. The excellent intraocular optics of this procedure provide a better visual outcome as compared with laser refractive surgery in high myopia. With advances in technology and IOL formulas, the predictability of refractive outcome after cataract surgery in high myopes has improved. The option of addressing presbyopia using multifocal/accommodating IOLs or monovision results in patients achieving reasonable spectacle independence. The most important concern with respect to phacoemulsification in high myopia is the risk of pseudophakic retinal detachment. High myopia is an independent risk factor for retinal detachment, and recent publications have reported a much lesser risk of retinal detachment specifically attributable to phacoemulsification in high myopes, especially if a thorough posterior segment evaluation is done and patients are followed up until development of complete posterior vitreous detachment. Refractive lens exchange is an effective and safe option to correct high myopia and can significantly improve quality of life in select patients.

Refractive lens exchange in modern practice: when and when not to do it?

Cataract surgery due to advances in small incision surgery evolved from a procedure concerned with the primary focus on the safe removal of cataractous lens to a procedure focused on the best possible postoperative refractive result. As the outcomes of cataract surgery became better, the use of lens surgery as a refractive modality in patients without cataracts has increased in interest and in popularity. Removal of the crystalline lens for refractive purposes or refractive lens exchange (RLE) presents several advantages over corneal refractive surgery. Patients with high degrees of myopia, hyperopia and astigmatism are still not good candidates for laser surgery. Moreover, presbyopia can currently only be corrected with monovision or reading spectacles.

RLE supplemented with multifocal or accommodating intraocular lenses (IOLs) in combination with corneal astigmatic procedures might address all refractive errors including presbyopia, and eliminate the future need for cataract surgery.

How to help children with neurodevelopmental and visual problems: a scoping review

Children with visual impairment and a condition affecting their neurodevelopment (children with VND) may require extensive and specialised help but evidence on the most effective strategies for visual improvement is lacking. We defined a PICO format (Population, Intervention, Comparator, Outcome) for a scoping review and systematically searched 13 databases. Two reviewers assessed the abstracts for inclusion and a third arbitrated in cases of disagreement. We abstracted data from included studies. We found 4450 abstracts from which we identified 107 papers for inclusion. Of these, 42 related to interventions involving a change in visual input or function: 5 controlled trials, 8 before and after studies and 29 case reports. The strongest evidence supported the provision of spectacles to improve distance or near vision and the use of ultraviolet light as environmental modification for training. Less strong but suggestive evidence supported training/practice routines to improve acuity or oculomotor control. Interventions exist to help children with VND and current recommendations that they are assessed by a vision specialist are supported by the evidence. More information is needed on the effectiveness of training/practice programmes which may promote improved function, and of environmental modifications to facilitate engagement of children with VND with the surroundings.

Refractive Surgery in Children

Refractive surgery in children is controversial. The main indications are bilateral high ametropia and anisometropia where conventional treatment with spectacles or contact lens is not tolerated. Other reported indications include accommodative strabismus and previous cataract surgery. The most commonly performed procedures currently are surface ablation procedures using excimer laser. The main disadvantage of surface ablation procedures is refractive regression, which is more pronounced in higher degrees of ametropia. More recently, there is a growing number of studies evaluating the safety and effectiveness of phakic intraocular lenses (IOLs) as an alternative surgical management for children who are noncompliant with conventional treatment and unsuitable for laser ablative procedures. The advantages of phakic IOLs are reversibility, predictability, and lack of regression. The principal concern with phakic IOL insertion is long-term endothelial cell loss. Clear lens extraction has been performed in patients with shallow anterior chambers beyond the range of corneal laser refractive procedures; however, major drawbacks include loss of accommodation and significant risk of retinal detachment. In summary, results to date show that refractive surgery can be successfully performed in children and meets an important need in a select subgroup of patients who are recalcitrant to traditional therapy. Issues that remain controversial are the age at which to perform surgery, choice of procedure, need for anesthesia, instability of refractive errors in children, and long-term safety considerations.

Pediatric refractive surgery: corneal and intraocular techniques and beyond

Refractive surgery has now been used successfully to treat severe anisometropia and isoametropia associated with amblyopia in children who cannot wear standard spectacles or contact lenses. Extraocular techniques include photorefractive keratectomy, laser-assisted subepithelial keratomileusis, and laser-assisted in situ keratomileusis. Intraocular techniques include refractive lensectomy and phakic intraocular lenses and are still being investigated in children for refractive errors outside the treatment dose capabilities of the excimer laser. This workshop discusses the various techniques, how and when to use each, and their risks and benefits. Newer techniques currently being used in adults that may someday be used in children are also introduced.

Refractive surgery in children

PURPOSE OF REVIEW

To evaluate recent literature regarding indications and outcomes for refractive surgery in children, including laser in-situ keratomileusis, laser epithelial keratomileusis, photorefractive keratectomy, and refractive intraocular lens placement.

RECENT FINDINGS

Refractive surgery in children is controversial. Recent publications have reported refractive surgery to treat strabismus and both ametropic and anisometropic amblyopia. Questions remain as to the age at which to perform the surgery, and which specific procedure to perform. Choice of technique depends on the clinical situation.

SUMMARY

Refractive surgery is an option for children with amblyopia and strabismus who fail treatment with spectacles or contact lenses. Prospective controlled studies are needed, and longer follow-up will answer questions about the utility and safety of refractive surgery in children.

Surgical intervention for traumatic cataracts in children: Epidemiology, complications, and outcomes

PURPOSE

To describe the presentation, treatment, and outcomes of a series of patients with unilateral traumatic cataracts.

METHODS

Retrospective, noncomparative review of 25 consecutive children with unilateral traumatic cataracts managed at a single institution during a 5-year period with regard to demographic data, mode of injury, clinical course, and outcome.

RESULTS

Paintball and BB gun injuries were the most common mode of injury, accounting for 28% of all cases, followed by injury from pens and pencils (16%). Preoperative visual acuity was poor in 19 patients (76%), and final postoperative visual acuity was poor (20/200 or worse) in 4 patients (16%); this difference was statistically significant (p < 0.001). Twenty-one percent of children with poor vision on initial examination had poor vision at their final examination, and no patients with vision better than 20/200 on initial examination developed poor vision postoperatively (p = 0.29). Patients who developed poor final vision were younger on average than those who achieved satisfactory vision (5.25 years vs 7.5 years). Poor visual outcome did not appear to depend on the time from injury to presentation and time interval between injury and cataract extraction.

CONCLUSIONS

Children with visually significant traumatic cataracts can have good outcomes if they are managed aggressively and appropriately. In our patient population, paintballs and BB guns accounted for more than 25% of traumatic cataract injuries, and a large number of traumatic cataracts were sustained by pens and pencils.

Refractive surgery in children: treatment options, outcomes, and controversies

PURPOSE

To summarize the evolution of the treatment of pediatric refractive errors, with an emphasis on recent advancements in the use of refractive surgery to treat children.

DESIGN

Literature review.

METHODS

We searched MEDLINE (1950 through October 2007), the Cochrane library (December through October 2007), and the Cumulative Index for Nursing and Allied Health Literature (December 1982 through October 2007) for English language articles using the following search strategy with MeSH terms and key words: pediatric refractive errors and amblyopia, anisometropia, hyperopia, myopia, laser in situ keratomileusis (LASIK), photorefractive keratectomy (PRK), laser epithelial keratomileusis (LASEK), excimer laser, refractive intraocular lens (IOL). We also searched the bibliographies of all identified articles.

RESULTS

No multicenter, long-term, controlled trial has been published on the use of refractive surgery in children. The current literature shows that LASIK, PRK, and LASEK show promising results in children with refractive amblyopia over the intermediate follow-up period. Corneal haze and myopic regression are the main complications, especially in very high myopia (> 12 diopters). In such patients with extremely high myopia, small studies have reported phakic IOLs or clear lens extraction with or without IOL implantation to be a useful alternative.

CONCLUSIONS

Refractive surgery is appropriate in children with severe anisometropia or bilateral high ametropia that is resistant to conventional therapy. More information is needed before pediatric refractive surgery can be widely adopted by the ophthalmic community. This could be achieved with a large, prospective, multicenter, randomized, controlled clinical trial.

Current thoughts in pediatric refractive surgery

The goal of this article is to review current literature regarding the emerging field of pediatric refractive surgery. This encompasses current thought in adult refractive surgery, published literature in pediatric refractive surgery, and future possibilities for refractive technology in the pediatric population. This study includes a comprehensive review of literature in the general refractive surgery, cornea, and pediatric literature.

Phakic intraocular lens correction of high ametropia in children with neurobehavioral disorders

PURPOSE

A subset of children with high ametropia and neurobehavioral disorders have chronic difficulties with spectacle or contact lens wear. We report the results of refractive surgery in a series of these children treated using bilateral or unilateral phakic intraocular lenses (IOLs) for ametropia >10 D.

METHODS

Clinical course and outcome data were collated prospectively in a group of 12 children (mean age, 10.1 years; range, 4-17 years) with neurobehavioral disorders exacerbated by poor compliance with spectacles. Myopia in 18 eyes ranged from -10.0 to -22.75 D (mean, -15.2 D) and in 2 hyperopic eyes from +10.25 to +10.75 (mean, +10.5 D). Goal refraction was approximately 0 to +1 D. Correction was achieved by implantation of an iris-enclaved phakic IOL under general anesthesia. Mean follow-up was 9.1 months (range, 3-15 months).

RESULTS

Myopia correction averaged 14.5 D and hyperopia correction 9.4 D. Eighty-six percent of eyes (17/20 eyes) were corrected to within +/- 1 D of emmetropia and the remaining 14% (3 eyes) to within +/- 2 D. Uncorrected visual acuity improved substantially in all 20 eyes (60-fold; from a mean of 20/3400 to a mean of 20/57). Ocular comorbidities in each child accounted for residual postoperative, subnormal visual acuity (eg, amblyopia, nystagmus, albinism, regressed retinopathy of prematurity). Visual functions (measured using a 23-item validated survey) improved. One eye required IOL exchange; no other clinically significant complications have been encountered.

CONCLUSIONS

Phakic IOL implantation improves visual function substantially in neurobehaviorally impaired children who have high ametropia and difficulties wearing glasses.

Diagnosis and treatment of refractive errors in the pediatric population

PURPOSE OF REVIEW

The diagnosis and successful treatment of visually significant refractive errors in children are a subject of continued study and debate.

RECENT FINDINGS

Treatment of significant refractive errors is widely accepted to reduce lifelong vision loss from amblyopia. Children aged 3-5 years may be screened for unexplained vision loss, refractive errors and amblyogenic factors using traditional eye charts as well as newer modalities such as autorefractors and photoscreeners. The accuracy of various screening methods is variable throughout the literature. Debate remains as to who is best suited to administer vision screening tests. Compliance with follow-up with an eye-care professional once a child is identified with an amblyogenic factor remains suboptimal. Treatment of significant refractive errors in certain populations of pediatric patients with refractive surgery shows promise but requires further study.

SUMMARY

The timely diagnosis of significant refractive errors in children remains a significant challenge, especially for ages 3-5 years, but treatment may provide significant improvement of visual acuity and quality of life.

Application of new ophthalmic technology in the pediatric patient

PURPOSE OF REVIEW

The present review will summarize briefly the recent advances in diagnostic tools, surgical techniques, and ophthalmic medications as they relate to the pediatric patient. The review will highlight results from studies that have investigated these new technologies and techniques.

RECENT FINDINGS

In the past several years there has been a plethora of literature on the application of new technologies and surgical techniques in children. New tools have been used for everything from gathering normative data about the pediatric eye to using the technologies to study diseases such as glaucoma and ocular tumors. Results of surgical techniques such as small-incision cataract surgery, sutureless vitrectomy, and refractive surgery are now reported with regularity in the pediatric ophthalmology literature.

SUMMARY

In the past 10 years pediatric ophthalmology has made significant advances. Technology has enabled us to qualify and quantify disease states more efficiently, and to explore new surgical techniques for disease processes that were formerly considered relatively untreatable.

Unilateral lens extraction for high anisometropic myopia in children and adolescents

INTRODUCTION

A subpopulation of children with anisometropic myopia, amblyopia, and neurobehavioral disorders is noncompliant with spectacle wear and ill-suited to correction using contact lenses. We report the results of refractive surgery in a series of these children treated using lensectomy alone (clear lens extraction) or lensectomy with simultaneous implantation of an intraocular lens (refractive lens exchange).

METHODS

Clinical course and outcome data were collated retrospectively in a group of 7 children and adolescents (mean age, 9.1 years; range, 4-20 years) with neurobehavioral disorders and noncompliance with spectacle wear for anisometropic myopia. Myopia in the 7 eyes ranged -11.9 to -24.5 D (mean, -16.7 D). Goal refraction was 0 to + 4 D. Correction was achieved by lensectomy in 5 eyes and lensectomy with intraocular lens implantation in 2 eyes. Primary posterior capsulectomy/subtotal vitrectomy was performed during the primary procedure in 5 eyes (71%). Mean follow-up was 3.8 years (range, 0.5-5.4 years).

RESULTS

Myopia correction averaged 17.3 D. A total of 86% (6 eyes) were corrected within +/- 3 D of the goal refraction and the remaining 14% to within +/- 4 D. Uncorrected visual acuity improved postoperatively in all 7 eyes, albeit modestly (average gain 0.14 Snellen fraction; gain from a mean 20/2550 to a mean 20/130). Myopic regression averaged approximately 0.43 D/year. Capsular opacification necessitated YAG-laser membranectomy in the 2 eyes that had preservation of the posterior capsule at the primary procedure. Retinal detachment has not occurred in any of the eyes during the follow-up period.

CONCLUSIONS

Refractive myopic lensectomy reduced high anisometropia and improved functional vision in children who have high myopia beyond the range of excimer laser correction and who will not wear glasses. Further study is indicated to determine the long-term safety of this procedure in similar pediatric populations.