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.

Small-aperture intracorneal inlay implantation in emmetropic presbyopic patients: a systematic review

Small-aperture corneal inlays, commonly known as KAMRA, are tiny optical devices inserted in the corneal stroma aiming to gain near vision in patients with presbyopia. The purpose of this study was to systematically review case series of small-aperture corneal inlays performed in presbyopic emmetropic patients and to evaluate the visual outcomes of this procedure. This systematic review included 18 articles published between 2011 and 2018, overall studying 2724 eyes from 2691 participants. The mean longest follow-up was 19 months. Results showed that 78.5% of eyes reported an uncorrected near visual acuity of 20/32 or better and 90.50% of eyes achieved an uncorrected distance visual acuity of 20/25 or better. All patients experienced an improvement in uncorrected near visual acuity with a patient satisfaction ranging between 60% and 90%. The highlighted complications were keratocyte activation leading to corneal stromal haze, epithelial growth, iron deposits and poor distance visual acuity. Explantation was carried out in 101 eyes (3.7%) due to distance vision blurriness, development of epithelial microcysts, incorrect implant placement or hyperopic shift changes. KAMRA demonstrated high efficacy. However, safety and satisfaction rates remain unclear. Despite the low explantation rates reported in the literature, some complications were permanent. The results and conclusions should be taken with caution due to the conflict of interest stated in the reviewed articles.

Myopia: Mechanisms and Strategies to Slow Down Its Progression

This topical review aimed to update and clarify the behavioral, pharmacological, surgical, and optical strategies that are currently available to prevent and reduce myopia progression. Myopia is the commonest ocular abnormality; reinstated interest is associated with high and increasing prevalence, especially but not, in the Asian population and progressive nature in children. The growing global prevalence seems to be associated with both genetic and environmental factors such as spending more time indoor and using digital devices, particularly during the coronavirus disease 2019 pandemic. Various options have been assessed to prevent or reduce myopia progression in children. In this review, we assess the effects of several types of measures, including spending more time outdoor, optical interventions such as the bifocal/progressive spectacle lenses, soft bifocal/multifocal/extended depth of focus/orthokeratology contact lenses, refractive surgery, and pharmacological treatments. All these options for controlling myopia progression in children have various degrees of efficacy. Atropine, orthokeratology/peripheral defocus contact and spectacle lenses, bifocal or progressive addition spectacles, and increased outdoor activities have been associated with the highest, moderate, and lower efficacies, respectively.

Visual outcomes of photorefractive keratectomy in non-children with anisometropic amblyopia: One-year Follow-up Outcomes

OBJECTIVE

To evaluate the safety, efficiency, short term stability, and sensory results of photorefractive keratectomy (PRK) in anisometropic in non-compliant children with correction.

METHODS

Twelve eyes of 12 children with an age range: 6-17 years and anisometropic amblyopia who underwent PRK under general anesthesia to correct the dioptric difference between the eyes were included in this study. A complete ophthalmic assessment including refractive status, uncorrected and corrected distance visual acuity (UDVA & CDVA), and binocular vision status using the Worth 4-dot test and stereopsis were performed before and 1, 3, 6, and 12 months after PRK.

RESULTS

The mean preoperative CDVA was 0.34 ± 0.24 LogMAR which showed a statistically significant improvement at 12 months (0.20 ± 0.19, p = 0.024) after surgery compared to the preoperative assessment. (p = 0.003) The mean preoperative UDVA was 0.63 ± 0.24 LogMAR that increased to 0.44 ± 0.24, 0.32 ± 0.16, 0.25 ± 0.19, and 0.25 ± 0.19 LogMAR at 1, 3, 6, and 12 months after PRK, respectively. One to three lines improvement in UDVA and CDVA was seen in 10 (83.4%) and 8 eyes (66.7%); while one line UDVA and CDVA loss was seen in one (8.3%) and one (8.3%) eye and unchanged UDVA and CDVA was seen in 1 (8.3%) and 3 eyes (25%), respectively. The mean preoperative stereoacuity was 341.9 ± 245.7 s of arc, which significantly improved to 166.6 ± 87.5 s of arc 12 months after PRK. (p = 0.012).

CONCLUSION

PRK was an effective surgical alternative to improve visual acuity and stereopsis in anisometropic children who did not cooperate with conventional methods of amblyopia therapy.

Management of amblyopia in pediatric patients: Current insights

Amblyopia is a cause of significant ocular morbidity in pediatric population and may lead to visual impairment in future life. It is caused due to formed visual deprivation or abnormal binocular interactions. Several risk factors in pediatric age group may lead to this disease. Author groups have tried managing different types of amblyopia, like anisometropic amblyopia, strabismic amblyopia and combined mechanism amblyopia, with optical correction, occlusion therapy, penalization, binocular therapy and surgery. We review historical and current management strategies of different types of amblyopia affecting children and outcomes in terms of visual acuity, binocularity and ocular deviation, highlighting evidence from recent studies. Literature searches were performed through Pubmed. Risk factors for amblyopia need to be identified in pediatric population as early in life as possible and managed accordingly, as visual outcomes in amblyopia are best if treated at the earliest. Although, monocular therapies like occlusion or penalization have been shown to be quite beneficial over the years, newer concepts related to binocular vision therapy are still evolving.

Small Incision Lenticule Extraction for Correction of Pediatric Unilateral Anisometropic Myopia

PURPOSE

To evaluate the effects of femtosecond laser small incision lenticule extraction (SMILE) on treating unilateral myopic anisometropia in children with spectacles or contact lens intolerance.

METHODS

This was a retrospective study that included children with unilateral myopic anisometropic amblyopia who underwent a SMILE procedure at Alpha Vision Center, Zagazig, Egypt, from January 2014 to December 2016.

RESULTS

One hundred twenty-four eyes of 124 patients were included in this study. The postoperative corrected distance visual acuity (CDVA) at the 3-month and 1-, 2-, 3-, and 4-year follow-up visits improved significantly (P < .05) compared to the preoperative CDVA, indicating the safety of the procedure. At the 3-month postoperative visit, 23% of cases showed improvement of one or more lines of CDVA, whereas only 2% of cases showed a decline of only one line. Moreover, the postoperative uncorrected distance visual acuity compared favorably to the preoperative CDVA, denoting the efficacy of the refractive correction. The spherical equivalent was within ±0.50 diopters of the intended correction in 75% of the cases and within ±1.00 diopters in 89% of the cases. The intraoperative complications were scarce and relatively innocuous.

CONCLUSIONS

SMILE is a safe and effective alternative method for correcting myopic anisometropic amblyopia in children with spectacles or contact lens intolerance with good refractive results. A larger study with longer follow-up periods is necessary to determine the long-term effects of SMILE. [J Refract Surg. 2021;37(8):510-515.].

Laser-assisted in situ keratomileusis long term outcomes in late adolescence

PURPOSE

Evaluate the long term outcomes of myopic-LASIK in a late adolescent population (age ⩾17 and <20 at the time of surgery).

METHODS

Monocentric retrospective case series study. Eyes with at least 3 years of follow-up time were included. Primary outcome measures were long term efficacy, safety and stability of the refractive error. Secondary outcome measure was the evaluation of the relation between the postoperative spherical aberration and the long term stability of the refractive error.

RESULTS

Forty-seven eyes of 25 patients were included. Mean follow-up was 9.23 ± 3.16 years. Mean age at the time of surgery was 18.74 ± 0.44 years. With time, postoperative UDVA showed a mild but significant deterioration of 1-2 Snellen lines (p = 0.012), in connection with a mild but significant myopization of the SE (mean increase of -0.43 D; p < 0.001), sphere (mean increase of -0.29 D; p = 0.004) and cylinder (mean increase of -0.16 D; p = 0.013). CDVA remained stable over time (p > 0.05). Efficacy index decreased from 1.01 to 0.87 in the long term (77% UDVA ⩾ 20/32). Safety remained at 1.06. 66% and 74% of eyes presented a SE within ±0.50 D and ±1.00 D respectively. SE changed over 0.50D in 33% of eyes. No correlation could be detected between the SE and the postoperative spherical aberration. No cases of corneal ectasia were detected.

CONCLUSIONS

Myopic-LASIK in late adolescence is safe and effective, but a mild myopic progression occurs. Despite presence of refractive stability is preferable, if necessary, myopic LASIK provides relatively good outcomes in the long term in this young population.

Femtosecond Laser-Assisted LASIK in Children With Hyperopia and Anisometropic Amblyopia: 7 Years of Follow-up

PURPOSE

To analyze clinical and functional results of femtosecond laser-assisted laser in situ keratomileusis (FSLASIK) in children with hyperopia and unilateral anisome-tropic amblyopia.

METHODS

The study included 24 patients (24 eyes) aged 5 to 15 years. Before the surgery, the mean manifest refractive spherical equivalent (MRSE) of amblyopic eyes was +3.90 ± 1.60 diopters (D) (range: +1.50 to +6.80 D) and the mean refractive anisometropia was 3.06 ± 1.64 D (range: 0.87 to 7.50 D). Every patient had at least 1 year of ineffective traditional amblyopia treatment before surgery. The mean follow-up period was 7 years (range: 6.9 to 7.4 years).

RESULTS

At the final follow-up visit, the mean MRSE of operated eyes was +0.41 ± 1.35 D (range: -1.13 to +3.88 D) (P < .001) and anisometropia in MRSE notation was 1.39 ± 1.15 D (range: 0.00 to 4.63 D). Postoperative spherical equivalent was within ±0.50, ±1.00, and ±2.00 D in 31%, 38%, and 92%, respectively. There were no complications. All patients showed a one to seven line gain of corrected distance visual acuity.

CONCLUSIONS

FS-LASIK was an effective method of hyperopia correction in this cohort of children with amblyopia, resulting in reduction in anisometropia, restoration of refractive balance, and functional improvement in the amblyopic eye when traditional methods failed. [J Refract Surg. 2020;36(6):366-373.].

[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.

Development of a core outcome set for amblyopia, strabismus and ocular motility disorders: a review to identify outcome measures

BACKGROUND

Core Outcome Sets (COS) are defined as the minimum sets of outcomes that should be measured and reported in all randomised controlled trials to facilitate combination and comparability of research. The aim of this review is to produce an item bank of previously reported outcome measures from published studies in amblyopia, strabismus and ocular motility disorders to initiate the development of COS.

METHODS

A review was conducted to identify articles reporting outcome measures for amblyopia, strabismus and ocular motility disorders. Using systematic methods according to the COMET handbook we searched key electronic bibliographic databases from 1st January 2011 to 27th September 2016 using MESH terms and alternatives indicating the different subtypes of amblyopia, strabismus and ocular motility disorders in relation to treatment outcomes and all synonyms. We included Cochrane reviews, other systematic reviews, controlled trials, non-systematic reviews and retrospective studies. Data was extracted to tabulate demographics of included studies, primary and secondary outcomes, methods of measurement and their time points.

RESULTS

A total of 142 studies were included; 42 in amblyopia, 33 in strabismus, and 68 in ocular motility disorders (one study overlap between amblyopia and strabismus). We identified ten main outcome measure domains for amblyopia, 14 for strabismus, and ten common "visual or motility" outcome measure domains for ocular motility disorders. Within the domains, we found variable nomenclature being used and diversity in methods and timings of measurements.

CONCLUSION

This review highlights discrepancies in outcome measure reporting within published literature for amblyopia, strabismus and ocular motility and it generated an item bank of the most commonly used and reported outcome measures for each of the three conditions from recent literature to start the process of COS development. Consensus among all stakeholders including patients and professionals is recommended to establish a useful COS.

[Pachymetric and topographic changes of cornea after femtosecond laser-assisted keratomileusis in hypermetropic children]

PURPOSE

To analyze the state of cornea using 'Pentacam' device data before and five years after femtolaser-assisted in situ keratomileusis (FS-LASIK) in hyperopic children.

MATERIAL AND METHODS

The study included 40 children aged 6-15 years examined before and five years after FS-LASIK.

RESULTS

Central corneal thickness (CCT) amounted to 548.88±37.24 μm, at 6.5 mm zone - 631.58±48.23 μm, at 8 mm zone - 723.61±57.7 μm. Five years after the surgery corneal thickness at main influence zone (6.5-8.0 mm from the center of the cornea) decreased in average by 6%. Pachymetry at the center showed 545.06±48.11 μm, at 6.5 mm zone - 592.54±36.55 μm, at 8 mm zone - 683.54±50.89 μm. Mean posterior corneal elevation was +21±3.75 μm. Keratotopographic indices ISV and IVA increased 3.6 and 2.7 times compared to initial data and amounted to 83.86±30 mm and 0.58±0.4 mm respectively. Other indices were IHA - 22.8±9.82 μm, R_min - 6.95±0.38 mm, KI - 1.1±0.09 and CKI - 1.05±0.03.

CONCLUSION

Monitoring of the cornea state with 'Pentacam' before and 5 years after hyperopic FS-LASIK in children on the background of stable refraction revealed changes of keratotopographic indices associated to corneal thickness change in the laser ablation zone and the absence of pathologic posterior corneal surface elevation. These changes reflect the corneal profile after laser correction of hyperopia and should be perceived as topographic 'pseudo keratectasia'.

[Morphological changes of cornea in children with hyperopia in the immediate and remote postoperative period after laser keratomieleusis according to confocal microscopy data]

Studying morphological changes of cornea in the remote postoperative period is becoming increasingly relevant with refractive surgeries being adapted for children.

PURPOSE

comparative analysis of keratocyte density and hystomorphologic changes of cornea after laser in situ keratomieleusis (LASIK) and femtosecond laser-assisted LASIK (FS-LASIK) in children with hyperopia.

MATERIAL AND METHODS

109 patients aged 6-17 years in 2 groups were examined with 'Confoscan-4' confocal microscope.

RESULTS

In comparison with initial data, keratocyte density decreased in the immediate postoperative period after FS-LASIK and LASIK in average by 17.09%, 64.31% and 12.2% in the corneal flap, directly in the laser influence zone (interface) and in the retroablation zone respectively. After 5 years, keratocyte density decreased in the corneal flap, interface zone and retroablation zone by 12.01%, 48.71% and 8.06% respectively in comparison with initial data. A circular scar at the flap edge was left after FS-LASIK; keratocyte density in the corneal flap and in the interface zone was in average 8.9% and 15.28% higher respectively, and twice more subepithelial nerves were noted compared to LASIK.

CONCLUSIONS

In the remote postoperative period keratocyte density in the corneal decreased in average by 43% after FS-LASIK and by 46% after LASIK in comparison with initial data. No changes were seen in the morphologic state of the cornea outside the influence zone. Both the technologies are safe, however keratocyte density and the number of subepithelial nerves are higher in the cornea flap and in the interface zone after FS-LASIK; corneal stability is assured by a circular scar formed at the flap edge.

Progression of High Anisometropia in Children

PURPOSE

To investigate the onset and rate of progression of high anisometropia in myopic children younger than 13 years.

METHODS

A retrospective study was performed on children with anisometropia younger than 13 years with myopia of more than 4.00 diopters (D) in the more ametropic eye and a difference in spherical equivalent refraction of 4.00 D between both eyes. All children had a complete ophthalmologic examination, including measurement of visual acuity and cycloplegic refraction every 3 to 6 months for at least 5 years. Change in the spherical equivalent and the cylindrical error for both eyes and changes in the difference in spherical equivalent refraction between both eyes were calculated for each patient at each visit. Linear, polynomial, logarithmic, and exponential fitting models were tested for both eyes and for the anisometropic difference between both eyes. The regression line with the greatest R² value was considered best fit.

RESULTS

Sixty-three patients fulfilled the inclusion criteria. The more ametropic eye grew in a regular fashion during the first 2 years of life, followed by a rapid decrease in the rate of growth to become almost stable after 4 years of age. The increase in myopia best fit a third-degree polynomial (cubic) model (R² = 0.98). The less ametropic eye showed only a small increase in myopia during the follow-up period. The anisometropic difference between both eyes increased gradually during the first 2 years, then remained stable.

CONCLUSIONS

High anisometropic myopia progresses rapidly in the first few years of life before becoming stable. [J Pediatr Ophthalmol Strabismus. 2017;54(5):282-286.].

V4B implantable collamer lens versus Intacs corneal rings to manage anisometropic myopic amblyopia in children

OBJECTIVE

To compare the safety and efficacy of phakic intraocular lens (PIOL) versus intrastromal corneal ring segments (Intacs), for correcting high myopic anisometropia in amblyopic children.

DESIGN

Nonrandomized prospective multi-center study.

PARTICIPANTS

Thirty children, aged between 4 and 12 years, with unilateral high myopic anisometropic amblyopia were included in this study.

METHODS

Patients who were prospectively subdivided into group A, with mean preoperative manifest refraction spherical equivalent (MRSE) of -12.96 ± 4.17 D, underwent unilateral phakic posterior chamber intraocular lens implantation. Patients with mean preoperative MRSE of -8.60 ± 1.16 D in group B were treated by Intacs corneal rings. Pre- and postoperative visual acuity, ocular examination, stereoacuity, axial biometry measurements, cycloplegic refraction, and endothelial cell counts were performed in all patients.

RESULTS

Group A revealed prevention of amblyopia with improvement in spectacle-corrected distance visual acuity, where 4-6 lines were achieved in 77% of children, 2-3 lines in 4%, and just 0-1 lines restricted to 19% of children. Improvement in stereoacuity was noted in 93.33% of group A cases, whereas group B showed fewer cases of successfully improved vision, with 4-6 lines in 70% of children, 2-3 lines in 3%, and just 0-1 lines restricted to 27% of children. Improvement in stereoacuity was noted in 86.66% of cases. Two cases of cataract and 1 case of glaucoma with 1 case of uveitis were noted in the implantable contact lens (ICL) group.

CONCLUSIONS

Posterior chamber PIOLs or Intacs may provide a safe alternative in treating anisometropic myopic patients. Intacs implantation is safer with fewer complications than ICL. However, ICL implantation is advantageous over the corneal ring segment procedure owing to the wide range of errors to correct.

Visual outcomes of laser vision correction in eyes with preoperative amblyopia

PURPOSE

To evaluate the visual outcomes of photorefractive keratectomy (PRK) and laser in situ keratomileusis (LASIK) in amblyopic eyes.

SETTING

Care Vision Refractive Clinic, Tel Aviv, Israel.

DESIGN

Retrospective case series.

METHODS

Amblyopic eyes of patients with a preoperative corrected distance visual acuity (CDVA) of 20/33 or worse had PRK or LASIK. Postoperative visual outcomes (uncorrected distance visual acuity, CDVA) and correlations with age, preoperative CDVA, refractive error type, astigmatism grade, procedure type, laser suite model, amblyopia grade, and amblyopia type were analyzed.

RESULTS

This study evaluated 327 eyes (327 patients). The CDVA improved more than 1, 2, and 3 Snellen lines in 147 eyes (45.0%), 75 eyes (22.9%), and 32 eyes (9.8%), respectively. Age (P = .007, B = 0.002), and preoperative CDVA (P < .001, B = -0.405) were significantly associated with CDVA improvement. The outcome in eyes with lower myopia was significantly better than in eyes with hyperopia (0.054 logMAR difference; P = .016) or high myopia (0.036 logMAR difference; P = .002). Moderately amblyopic eyes had significantly better visual outcomes than mildly amblyopic eyes (0.038 logMAR difference; P = .001). No significant difference was found between PRK and LASIK (P = .262).

CONCLUSIONS

Laser vision correction, regardless of the type of procedure (LASIK or PRK) might improve CDVA in a large portion of amblyopic patients. Improvement was greater in younger patients, eyes with lower initial CDVA, and eyes with lower myopia.

Management of pseudophakic myopic anisometropic amblyopia with piggyback Visian® implantable collamer lens

PURPOSE

To assess the outcomes of sulcus implantation of the Visian^® implantable collamer lens (ICL) to correct pseudophakic myopic anisometropic amblyopia with myopic shift and/or primary refractive overcorrection.

METHODS

Prospective case series enrolled 14 pseudophakic eyes of 14 patients, 5-9 years old, with history of cataract surgery and primary in the bag-intraocular lenses (IOL) implantation, followed by myopic shift and/or refractive overcorrection and anisometropic amblyopia of variable degrees. All cases had implantation of a piggyback ICL/toric ICL, to correct the myopia/myopic astigmatism. Preoperatively, we evaluated the uncorrected distance visual acuity (UCVA), corrected distance visual acuity (CDVA), manifest refraction spherical equivalent (MRSE), intraocular pressure (IOP) and endothelial cell density (ECD). We assessed the position and vaulting of the ICLs on slit lamp examination and confirmed by Scheimpflug tomography. Postoperative follow-up was at 1st week and 1, 3, 6, 9, 12, 18 and 24 months.

RESULTS

Uncorrected distance visual acuity improved in all cases, and CDVA improved in 11 amblyopic eyes (2-4 lines). There was no evidence of interlenticular opacification (ILO) throughout the 2-year follow-up. Two cases were complicated with early postoperative acute elevation of IOP and were controlled with topical beta-blockers. Postoperative acute anterior uveitis occurred in six eyes and controlled by topical steroids. Implantable collamer lens (ICL) vault was measured using Pentacam, with mean value of 470 ± 238 μm.

CONCLUSION

Sulcus implantation of the secondary piggyback ICL to correct unilateral pseudophakic myopic refractive error in children was safe, efficient, predictable and well tolerated in management of anisometropic amblyopia in all eyes.

[Analysis of corneal biomechanical changes after femtosecond laser-assisted laser in situ keratomileusis in children with hyperopic anisometropia]

AIM

to analyze corneal hysteresis (CH) and corneal resistance factor (RF) readings obtained with the Reichert Ocular Response Analyzer (ORA) before and after hyperopic femtolaser-assisted laser in situ keratomileusis (FS-LASIK) in children with anisometropia as well as to establish factors that may cause changes in these parameters.

MATERIAL AND METHODS

CH and RF were evaluated before and 1.5 years after FS-LASIK performed on amblyopic eyes of 28 patients aged 6-14 years. Preoperatively, there was a correlation between CH and RF (r=0.41, p=0.03). No correlation was found between CH and age (r=-0.02, p=0.82) or between CH (r=0.00, p=0.98), RF (r=0.04, p=0.83), and cornea thickness.

RESULTS

The mean preoperative CH was 12.56±1.21 mmHg, RF 12.31±1.57 mmHg. Postoperatively, a statistically significant change occurred to both CH (by 0.97±1.51 mmHg, p=0.002) and RF (by 1.42±1.55 mmHg, p=0.000). No correlation was found between CH before and after surgery (r=0.11, p=0.57) as well as between the ablation depth and changes in CH (r=0,04, p=0.83) and RF (r=0.21, p=0.28). Regression analysis showed that the extent of CH (r2=0.52, p=0.00) and RF (r2=0,48, p=0.00) changes was closely related to their preoperative values.

CONCLUSION

The statistically significant relative change in CH and RF after hyperopic FS-LASIK was 8% and 12%, respectively. CH and RF changes correlated with their preoperative values, but not with the ablation depth or cornea thickness.

Acute hydrops with secondary bacterial keratitis: sequelae of paediatric refractive surgery

A 24-year-old male patient with bilateral high myopia presented to our outpatient department with sudden onset of pain and diminution of vision in his right eye. He had sequentially undergone bilateral trabeculectomy and photorefractive keratectomy at the age of 6 years in both eyes. This was followed by radial keratotomy in right eye at the age of 8 years. The slit lamp examination demonstrated the presence of infiltrates in central cornea with an underlying fluid cleft, along with 14 radial keratotomy scars. Anterior segment optical coherence tomography confirmed the presence of intrastromal cleft in communication with anterior chamber. Bacterial culture revealed coagulase-negative Staphylococcus. The patient was successfully treated with fortified antibiotics in conjunction with the sensitivity report. This case underlines the need for a cautious approach towards refractive surgery in paediatric age group and highlights the long-term sequelae of retreatments in these cases.

Laser in situ keratomileusis in 2012: a review

Laser in situ keratomileusis (LASIK) is a safe and effective treatment for refractive error. A combination of technological advances and increasing surgeon experience has served to further refine refractive outcomes and reduce complication rates. In this article, we review LASIK as it stands in late 2012: the procedure, indications, technology, complications and refractive outcomes.

Influence of patient age on high myopic correction in corneal laser refractive surgery

PURPOSE

To evaluate the influence of patient age on the postoperative outcomes in eyes with myopia higher than 5.00 diopters (D) that had laser in situ keratomileusis using the Schwind Amaris laser system.

SETTING

Private practice, Utrecht, The Netherlands.

DESIGN

Case series.

METHODS

At the 1-year follow-up, right eyes with preoperative myopia higher than 5.00 D were analyzed. The effect of the patient's age on postoperative status was assessed using univariate linear and multilinear correlations.

RESULTS

The study analyzed 612 eyes. Univariate linear analyses showed that residual refraction was correlated with patient age. Univariate multilinear analyses showed that spherical equivalent (SE) was correlated with the attempted SE and patient age, whereas cylinder was correlated with attempted cylinder only. Analyses suggested overcorrections and higher residual astigmatism values for older patients.

CONCLUSIONS

Patient age affected postoperative outcomes in a subtle, yet significant manner. An age-dependent adjustment toward greater attempted correction in younger patients and less intended correction in older patients may help optimize refractive outcomes.

FINANCIAL DISCLOSURE

Drs. Ewering and Arba-Mosquera are employees of Schwind eye-tech-solutions GmbH. Dr. Luger has no financial or proprietary interest in any material or method mentioned.

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.