Pediatric refractive surgery: current opinion in ophthalmology.

PURPOSE OF REVIEW: Pediatric refractive surgery has been growing at a steady pace since its introduction in the early 1980 s. This article will review common laser refractive surgeries performed on pediatric patients along with controversies regarding the practice. RECENT FINDINGS: Pediatric refractive surgery is reserved for a small population of children who fail amblyopic treatment due to high anisometropic refractive errors. Publications over the years have treated these children with various types of laser refractive surgery. SUMMARY: Laser pediatric refractive surgery appears to be well tolerated and effective for the population of children that need it. It provides an alternative for anisometropic amblyopia treatment for children who would have otherwise not been able to improve their vision.

Surgical interventions for bilateral congenital cataract in children aged two years and under.

BACKGROUND: Congenital cataracts are lens opacities in one or both eyes of babies or children present at birth. These may cause a reduction in vision severe enough to require surgery. Cataracts are proportionally the most treatable cause of visual loss in childhood, and are a particular problem in low-income countries, where early intervention may not be possible. Paediatric cataracts provide different challenges to those in adults. Intense inflammation, amblyopia (vision is obstructed by cataract from birth which prevents normal development of the visual system), posterior capsule opacification and uncertainty about the final trajectory of ocular growth parameters can affect results of treatment. Two options currently considered for children under 2 years of age with bilateral congenital cataracts are: (i) intraocular lens (IOL) implantation; or (ii) leaving a child with primary aphakia (no lens in the eye), necessitating the need for contact lenses or aphakic glasses. Other important considerations regarding surgery include the prevention of visual axis opacification (VAO), glaucoma and the route used to perform lensectomy. OBJECTIVES: To assess the effectiveness of infant cataract surgery or lensectomy to no surgery for bilateral congenital cataracts in children aged 2 years and under. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL; which contains the Cochrane Eyes and Vision Trials Register; 2022, Issue 1); Ovid MEDLINE; Ovid Embase; the ISRCTN registry; ClinicalTrials.gov and the WHO ICTRP. The date of the search was 25 January 2022. SELECTION CRITERIA: We included all randomised controlled trials (RCTs) that compared infant cataract surgery or lensectomy to no surgery, in children with bilateral congenital cataracts aged 2 years and younger. This update (of a review published in 2001 and updated in 2006) does not include children over 2 years of age because they have a wider variety of aetiologies, and are therefore managed differently, and have contrasting outcomes. DATA COLLECTION AND ANALYSIS: We used standard methods expected by Cochrane. Two review authors extracted data independently. We assessed the risk of bias of included studies using RoB 1 and assessed the certainty of the evidence using GRADE. MAIN RESULTS: We identified three RCTs that met our inclusion criteria with each trial comparing a different aspect of surgical intervention for this condition. The trials included a total of 79 participants under 2 years of age, were conducted in India and follow-up ranged from 1 to 5 years. Study participants and outcome assessors were not masked in these trials. One study (60 children) compared primary IOL implantation with primary aphakia. The results from this study suggest that there may be little or no difference in visual acuity at 5 years comparing children with pseudophakia (mean logMAR 0.50) and aphakia (mean logMAR 0.59) (mean difference (MD) -0.09 logMAR, 95% confidence intervals (CIs) -0.24 to 0.06; 54 participants; very low-certainty evidence), but the evidence is very uncertain. The evidence is very uncertain as to the effect of IOL implantation compared with aphakia on visual axis opacification (VAO) (risk ratio (RR) 1.29, 95% CI 0.23 to 7.13; 54 participants; very low-certainty evidence). The trial investigators did not report on the cases of amblyopia. There was little evidence of a difference betwen the two groups in cases of glaucoma at 5 years follow-up (RR 0.86, 95% CI 0.24 to 3.10; 54 participants; very low-certainty evidence). Cases of retinal detachment and reoperation rates were not reported. The impact of IOL implantation on adverse effects is very uncertain because of the sparse data available: of the children who were pseudophakic, 1/29  needed a trabeculectomy and 8/29 developed posterior synechiae. In comparison, no trabeculectomies were needed in the aphakic group and 2/25 children had posterior synechiae (54 participants; very low-certainty evidence).  The second study (14 eyes of 7 children under 2 years of age) compared posterior optic capture of IOL without vitrectomy versus endocapsular implantations with anterior vitrectomy (commonly called 'in-the-bag surgery'). The authors did not report on visual acuity, amblyopia, glaucoma and reoperation rate. They had no cases of VAO in either group. The evidence is very uncertain as to the effect of in-the-bag implantation in children aged under 1 year. There was a higher incidence of inflammatory sequelae: 4/7 in-the-bag implantation eyes and 1/7 in optic capture eyes (P = 0.04, 7 participants; very low-certainty evidence). We graded the certainty of evidence as low or very low for imprecision in all outcomes because their statistical analysis reported that a sample size of 13 was needed in each group to achieve a power of 80%, whereas their subset of children under the age of 1 year had only 7 eyes in each group. The third study (24 eyes of 12 children) compared a transcorneal versus pars plana route using a 25-gauge transconjunctival sutureless vitrectomy system. The evidence is very uncertain as to the effect of the route chosen on the incidence of VAO, with no cases reported at 1 year follow-up in either group. The investigators did not report on visual acuity, amblyopia, glaucoma, retinal detachment and reoperation rate. The pars plana route had the adverse effects of posterior capsule rupture in 2/12 eyes, and 1/12 eyes needing sutures. Conversely, 1/12 eyes operated on by the transcorneal route needed sutures. We graded the outcomes with very low-certainty because of the small sample size and the absence of a priori sample size calculation. AUTHORS' CONCLUSIONS: There is no high level evidence for the effectiveness of one type of surgery for bilateral congenital cataracts over another, or whether surgery itself is better than primary aphakia. Further RCTs are required to inform modern practice about concerns, including the timing of surgery, age at which surgery should be undertaken, age for implantation of an IOL and development of complications, such as reoperations, glaucoma and retinal detachment. Standardising the methods used to measure visual function, along with objective monitoring of compliance with the use of aphakic glasses/contact lenses would greatly improve the quality of study data and enable more reliable interpretation of outcomes.

Evaluation of the efficacy, safety, and stability of posterior chamber phakic intraocular lenses for correcting intractable myopic anisometropic amblyopia in a pediatric cohort.

BACKGROUND: Myopic anisometropic amblyopia in pediatrics is one of the most challenging clinical situations that can face an ophthalmologist. Conventional correction modalities for myopic anisometropia, using spectacles, contact lenses, and/or occlusion therapy, may not be suitable for some pediatric patients or for some ocular conditions. This may lead to the development of anisometropic amblyopia. The aim of the present study was to evaluate the visual and the refractive efficacy, safety, and stability of Posterior Chamber Phakic Intraocular Lenses (PC-pIOLs) for correcting myopic anisometropic amblyopia in a pediatric cohort. METHODS: This case series, prospective, interventional study was conducted at Watany Eye Hospital, Cairo, Egypt. It comprised children and teenagers with myopic anisometropic amblyopia and unsuccessful conventional therapy. After implantation of Intraocular Collamer Lenses "ICLs" (Visian ICL, Model V4c, STAAR Surgical, Monrovia, California, USA), postoperative follow-up visits were scheduled, with automated refraction and Pentacam imaging performed. RESULTS: The study enrolled 42 eyes of 42 patients. The age range was 3 to 18 years (mean ± SD = 10.74 years ±4.16). The mean preoperative spherical equivalent (SE) was - 12.85 D ± 2.74. The results declared a significant improvement in the postoperative Corrected Distance Visual Acuity "CDVA" (P value < 0.01) and SE (P value < 0.01). The efficacy index had a value of 1.18 ± 0.3 and the safety index was 1.09 ± 0.24. The follow-up visits had a mean ± SD of 14.67 months ±16.56 (range of 1 to 54 months). The results showed a refractive stability, with statistically insignificant improvements in the patients' visual acuity and refractive status on evaluating the enrolled pediatrics during the follow-up visits compared to the first postoperative visits. No postoperative complications were encountered. Worthy of mention is that there was a significant (80%) non-compliance with the prescribed postoperative occlusion therapy. CONCLUSIONS: The present study, with the longest reported follow-up range, declared the long-term efficacy, safety, and stability of Visian ICLs for correcting myopic anisometropic amblyopia in pediatrics. The reported non-compliance with occlusion therapy validates the early implantation of Visian ICLs in cases with failed conventional therapy to guard against anisometropic amblyopia.

Fixation stability after surgical treatment of strabismus and biofeedback fixation training in amblyopic eyes.

BACKGROUND: Visual fixation may be affected in amblyopic patients and, moreover, its stability may be associated with the effects of amblyopic treatments on visual performance in patients with strabismus. Therefore, fixation stability is a relevant biomarker that might predict the recurrence of amblyopia after a therapeutic intervention. Microperimetric biofeedback fixation training (BFT) can stabilize visual fixation in adult patients with central vision loss. It was the purpose of the present study to evaluate the effects of BFT on fixation stability in adult amblyopic patients after surgical intervention to treat strabismus. METHODS: Participants were 12 patients with strabismus (mean age = 29.6 ± 8.5 years; 6 females) and 12 healthy volunteers (mean age = 23.8 ± 1.5 years; 9 females). The protocol included ophthalmological and microperimetric follow-ups to measure fixation stability and macular sensitivity. BFT was applied monocularly to four amblyopic eyes either on the spontaneous preferential retinal locus or to a fixation area closer to the anatomical fovea after surgical treatment of strabismus. RESULTS: Baseline measurements showed significantly altered microperimetric average threshold in amblyopic eyes compared to fellow eyes (p = 0.024) and compared to control eyes (p < 0.001). Fixation was unstable in amblyopic eyes compared to control eyes (p < 0.001). Fixation stability did not significantly change after surgical alignment of strabismus (p = 0.805). BFT applied to operated eyes resulted in a more stable fixation with improvements of about 50% after three months of training. CONCLUSIONS: Fixation stability improvements following BFT highlight its potential use in adult amblyopic eyes after the surgical alignment of the strabismus. Future investigations may also consider applying this method in combination with standard treatments to improve vision in amblyopic patients.

Treatment of Congenital Ptosis in Infants With Associated Amblyopia Using a Frontalis Muscle Flap Eyelid Reanimation Technique.

PURPOSE: To determine the efficacy of a frontalis muscle flap eyelid reanimation technique for correction of severe congenital ptosis and associated amblyopia in infants. METHODS: The authors performed a retrospective chart review of patients 12 months of age or younger with unilateral or bilateral congenital ptosis and associated amblyopia or deemed at high risk for amblyopia due to visual deprivation. Following ptosis repair via a frontalis muscle flap technique, primary outcomes of postoperative eyelid position and amblyopia reversal were assessed. RESULTS: Seventeen eyes of 12 participants were included for study. Seven of these patients had simple congenital ptosis, and the remainder had ptosis as part of a syndrome. Nine were diagnosed with amblyopia preoperatively, and the remaining 3 were too young for acuity testing but had occlusion of the visual axis by the ptotic eyelid in primary gaze. Postoperatively, the mean margin-to-reflex distance 1 was 2.4 mm (range: 0.0-4.0), and 9 patients (75%) demonstrated no evidence of amblyopia. Only 2 patients had eyelid asymmetry greater than 2 mm, which in both cases was due to lack of frontalis activation by the patient secondary to ongoing visual impairment. The most common complication was lagophthalmos in 6 eyes (35.3%), with no significant associated surface keratopathy. CONCLUSIONS: The frontalis muscle flap technique may offer a new and effective approach to treating infants with severe congenital ptosis causing poor eyelid excursion and associated amblyopia while avoiding use of an implant.

Visual outcomes after refractive laser corneal surgery and phakic IOL in amblyopic eyes.

PURPOSE: To evaluate the outcomes of laser corneal surgery and phakic IOL surgery in adult amblyopic eyes. METHODS: Retrospective assessment was done in 688 amblyopic eyes 640 patients who underwent LASIK or phakic IOLs. Ophthalmological evaluation included measurement of uncorrected (UDVA) and corrected (CDVA) distance visual acuities. Analysis of modulation transfer function (MTF) was also done post-operatively as a measure of contrast sensitivity. Patients completed follow-up examinations at 1 day, 3 day, 3 months and 12 months after surgery. RESULTS: The mean patient age was 24.30 ± 3.04 years with 59% females. The CDVA of amblyopic eyes improved significantly from the mean preoperative level of 0.48 ± 0.18 to 0.59 ± 0.18 at 12 months. There was improvement in the contrast sensitivity at all spatial frequencies. Refractive errors were corrected in both LASIK and phakic IOL group, but there was no clinically significant difference in visual outcomes between each group. CONCLUSION: Laser vision correction and phakic IOL surgery for amblyopic eyes are promising alternative methods for improving visual outcomes in adult refractive amblyopia patients who have failed with conventional approaches.

Management of epiblepharon: state of the art.

PURPOSE OF REVIEW: Epiblepharon is prevalent in East-Asian children. As the population in Asia is increasing, so is the demand for epiblepharon surgery. Surgeons should be familiar with the standards of beauty and needs of Asian people for epiblepharon management. This review provides a comprehensive summary of the published studies on the clinical manifestations, pathophysiology, and management of epiblepharon. RECENT FINDINGS: Astigmatism is prevalent in epiblepharon patients, which can contribute to amblyopia. Early surgery and visual rehabilitation is important for epiblepharon patients with a high degree of astigmatism and amblyopia. Various etiologic factors play a role in the pathophysiology of epiblepharon. Surgical procedures focusing on creation of a lower eyelid crease have been popular for treating epiblepharon in Western textbooks; however, this is not appropriate for Asian patients in whom, a crease may be undesirable. In selecting surgical methods, it is important to resect a minimal amount of skin-muscle to avoid the adverse effects of ectropion and eyelid retraction. SUMMARY: Although epiblepharon may resolve with facial growth, surgical correction is needed for cases in which there is significant corneal injury from the lash touch. Surgical management should focus on techniques that are effective, with little chance of complication, and do not create a lower eyelid crease.

Posterior chamber toric phakic IOL implantation for the management of pediatric anisometropic amblyopia.

PURPOSE: To report the outcomes of toric posterior chamber phakic intraocular lens (PIOL) implantation in children for the treatment of amblyopia due to anisometropia with astigmatism. METHODS: Six eyes of 6 amblyopic patients aged 5 to 15 years underwent toric PIOL (Visian Toric ICL; STAAR Surgical Company, Monrovia, CA) implantation for refractory anisometropic amblyopia. Preoperative and postoperative clinical evaluation included slit-lamp microscopy, visual acuity, anterior/posterior segment examination, and cycloplegic refraction. RESULTS: After a mean follow-up of 23 months (range: 15 to 34 months), mean spherical equivalent cycloplegic refraction improved from -10.21 ± 4.62 diopters (D) (range -7.5 to -19.5 D) preoperatively to -0.42 ± 0.39 D (range: -0.625 to +0.125 D) postoperatively. Corrected distance visual acuity ranged from 20/40 to 20/200 preoperatively and 20/20 to 20/60 postoperatively. Five of the 6 eyes gained more than 3 lines of corrected distance visual acuity with a maximum gain of 8 lines in one eye. One eye showed an improvement of more than 2 lines (change in preoperative visual acuity of 20/100 to 20/60 postoperatively). No patients lost any lines of visual acuity. All eyes remained quiet. All PIOLs remained well centered throughout the follow-up period. CONCLUSION: Toric PIOL implantation may be a viable therapeutic modality in children with clinically significant anisometropic ametropia and astigmatism with secondary amblyopia who have been refractory to medical treatment including spectacles or contact lenses. Longer follow-up visits with larger sample populations will evaluate more effectively the long-term efficacy and late-onset of complications.

CHANGES IN THE VISION OF ADULT AMBLYOPIC PATIENTS FOLLOWING CLEAR LENS EXTRACTION.

AIMS: The aim of the study was to retrospectively evaluate changes in vision after the implantation of trifocal (tIOL) or rotationally asymmetric multifocal artificial intraocular lenses (mIOL) in patients undergoing clear lens extraction. The main goal was to determine whether changes to central visual acuity occur after the implantation of an IOL at a follow-up examination after one year. Other objectives were to determine the difference between the groups with implanted diffractive and rotationally asymmetric artificial intraocular lenses, as well as to evaluate the risk of accurate correction in patients who had lived most of their lives "undercorrected". MATERIAL AND METHODS: In our study, we present a retrospective longitudinal evaluation of results in patients after the implantation of an artificial intraocular lens. In the period from 2013 to 2020, we evaluated changes in the vision of 22 patients aged 39-59 years, of whom 18 were women and 5 were men. The average preoperative refraction of myopic eyes was +5.7 ±2.13 Dsf and +1.24 ±0.86 Dcyl. In amblyopic eyes, 7 diffractive lenses and 15 rotationally asymmetric lenses were used. RESULTS: Uncorrected distance visual acuity before surgery and one year (1Y) after was 0.13 ±0.09 vs. 0.57 ±0.28 (p < 0.001); the best corrected distance visual acuity before and 1Y after was 0.53 ±0.22 vs. 0.62 ±0.29 (p = 0.024); uncorrected near visual acuity before and 1Y after was 0.06 ±0.06 vs. 0.48 ±0.32 (p < 0.001); the best corrected near visual acuity before and afér the surgical procedure was 0.45 ±0.27vs. 0.55 ±0.35 (p = 0.014). CONCLUSION: Implantation of tIOL and mIOL lenses was effective in our group of patients with amblyopia, thus improving uncorrected distance and near visual acuity and without serious adverse effects. At the same time, we evaluate that the change in refraction and the removal of anisometropia lead to a significant change in the best corrected visual acuity for distance or near vision at the one-year follow-up examination.

Evaluation of the efficiency and safety of TransPRK and FS-LASIK refractive procedures on patients with astigmatism and amblyopia.

Purpose: To compare the outcomes of transepithelial photorefractive keratectomy (transPRK) with femtosecond laser assisted in situ keratomileusis (FS-LASIK) for the correction of astigmatism on amblyopic eyes. Methods: The design was a retrospective interventional study on 37 eyes with hyperopic or mixed astigmatism and refractive amblyopia, which underwent transPRK or FS-LASIK. The patients were distributed into 2 groups according to the technique used. Data was collected from patient files and comparison between groups was performed. The main outcomes measured were corrected distance visual acuity (CDVA), sphere, cylinder, spherical equivalent (SEQ), efficiency and safety indexes. Results: In the transPRK group, SEQ improved significantly after 1 month, from 2.08 ± 2.02D (p<0.01) to 0.125 ± 0.86D and at the 12 month visit to -0.04 ± 0.62D (p>0.05), sphere improved from 4.03 ± 1.44D preoperatively to 0.67 ± 0.9D at 1 month (p<0.05) and further to 0.44 ± 0.71 at 12 months (p<0.05). CDVA improved from 0.194 ± 0.11 logMAR to 0.115 ± 0.1 logMAR at the 1-year visit. Safety index after 1 month was 1.09 ± 0.2 and 1.12 ± 0.35 at the 1-year visit. Efficiency index was 0.95 ± 0.22 at 1 month and 1.03 ± 0.34 after 1 year. In FS-LASIK group, SEQ improved after 1 month, from 2.28 ± 3.04 to -0.79 ± 0.73D (p<0.01), and further to -0.49 ± 0.79 (p>0.05) at the 12 month visit, sphere improved from 4.11 ± 2.35D preoperatively to -0.42 ± 0.66D at 1 month (p<0.05) and further to -0.08 ± 0.75D at 12 months (p<0.05). CDVA also improved from 0.191 ± 0.1 logMAR to 0.140 ± 0.1 logMAR at 1 year. Safety index after 1 month was 1.1 ± 0.2 and 1.16 ± 0.21 at the 1-year visit. Efficiency index was 0.98 ± 0.27 at 1 month and 1.06 ± 0.23 after 1 year. Conclusion: Both procedures were safe and efficient in improving visual acuity for patients with mixed and hyperopic astigmatism and refractive amblyopia. Abbreviations: transPRK = transepithelial photorefractive keratectomy, FS-LASIK = femtosecond laser in situ keratomileusis, logMAR = logarithm of the Minimum Angle of Resolution, BCVA = best corrected distance visual acuity, CDVA = corrected distance visual acuity.

Basic acquired nonaccommodative esotropia patients managed with surgery; a study of 2102 patients.

INTRODUCTION: Several studies investigated preoperative clinical features of patients with basic-acquired nonaccommodative esotropia (BANAET); however, their sample sizes were small, and they did not compare the clinical features among cases that needed different surgery times. The main purpose of this study is to compare the preoperative clinical features of patients with BANAET managed with one surgery with patients who underwent two or more strabismus surgery over 10 years. METHODS: This historical cohort study was performed on the hospital records of 13,252 Iranian strabismic patients who underwent surgery at Farabi eye hospital, Tehran, Iran, from 2012 to September 2022. Of those, 2102 cases with BANAET were selected as the sample size. Data collected included sex, age at the time of first surgery, corrected distance visual acuity (CDVA), refractive error, presence of amblyopia, angle of deviation, and times of surgery. RESULTS: The mean age was 18.9 ± 15.6 [1200 (57.1%) males and 902 (42.9%) females] and the median age was 14 years. In 1599 (76.1%) patients, esotropia was managed with one surgery; however, 342 (16.3%) cases were managed with two surgeries and 161 (7.6%) patients underwent three or more surgeries. The mean angle of horizontal deviation at distance and near in patients managed with two and ≥3 surgeries was significantly higher than in cases managed with one surgery (P < .001). Amblyopia was observed in 289 (18.1%) patients who were managed with one surgery, 69 (20.2%) patients with two surgeries and 43 (26.7%) patients with three or more surgeries (P < .001). Patients with BANAET managed successfully with only one surgery were younger, had better CDVA, lower astigmatism and less horizontal angle of deviation at distance and near than those who underwent two or more surgeries (all P < .001). DISCUSSION: The higher astigmatism, lower CDVA, greater angle of horizontal deviation, and higher frequency of amblyopia were found in the preoperative examinations of BANAET patients managed with two or more surgeries compared with cases managed with only one surgery.

[Mobius syndrome]. / Sindrom mobius.

Mobius syndrom, an anomaly in cranial nerve developement, presents with a remarkable clinical polymorphism. The rare occurence of this pathology and the questions raised by the diagnosis and treatment determined us to make this presentation.

Visual and refractive outcomes of monofocal toric intraocular lens implantation in amblyopic eyes.

PURPOSE: To evaluate the visual and refractive outcomes of monofocal toric intraocular lens (IOL) implantation after cataract surgery in amblyopic eyes. METHODS: Our center's database was used to identify patients who had undergone bilateral cataract surgery between 2016 and 2020 with the implantation of a toric IOL in their amblyopic eye. Exclusion criteria were the presence of strabismus, ocular pathologies other than cataract or intra-surgical complications. The outcomes analysed were uncorrected distance visual acuity (UDVA), subjective refraction and corrected distance visual acuity (CDVA) one month after surgery. RESULTS: Ninety patients were included, with a mean age of 68.96 ± 7.81years. CDVA was lower for the amblyopic eye, both before and after surgery. There was a mean improvement in CDVA of 0.23 ± 0.21 LogMAR for the dominant eye and of 0.39 ± 0.33 for the amblyopic eye, p < 0.001 in both cases. Postoperative subjective refractive cylinder was higher in the amblyopic eye (-0.24 ± 0.39 D versus -0.10 ± 0.25 D, p < 0.01), as well as mean cylinder prediction error (-0.30 ± 0.47 D versus 0.02 ± 0.42 D, p < 0.01), compared to the dominant eye. There was a statistically significant correlation between preoperative and postoperative CDVA in amblyopic eyes (Spearmans Rho = 260, p = 0.013). Mean postoperative UCVA was 0.15 ± 0.25 for amblyopic and 0.03 ± 0.12 for dominant eyes. Only one patient required distance spectacle correction due to residual astigmatism. CONCLUSIONS: Cataract surgery with toric IOL implantation in amblyopic eyes leads to an improvement in visual acuity and to spectacle independence in almost all cases, even in the presence of a higher cylinder prediction error.

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.

Update on pediatric corneal diseases and keratoplasty.

Managing pediatric corneal disorders is challenging as the prognosis of pediatric keratoplasty depends on several factors. Advancements in the genetic basis of congenital corneal diseases and investigations in congenital corneal conditions provide a better understanding of pediatric corneal conditions. Surgeons performing keratoplasty in children now have a choice of various techniques. Evolving surgical techniques of anterior lamellar and endothelial keratoplasties have expanded the management interventions in these pediatric corneal morbidity conditions; however, considerable concerns still exist in association with corneal transplantation in infants and children. Outcomes in pediatric keratoplasty depend upon the preoperative indications, the timing of surgical intervention, intraoperative and postoperative factors including the patient/care givers' compliance. Factors such as low scleral rigidity, higher rate of graft failure, need for frequent examinations under anesthesia, and difficulty in optimal visual acuity assessment still remain a considerable challenge in pediatric scenarios. In children, deprivation amblyopia as a result of the corneal opacification can adversely affect visual development, causing dense amblyopia. Outcomes to surgical interventions for management of corneal opacification in children are further compromised by the preexisting amblyopia apart from the concerns of refractive outcome of the graft. Graft rejection, graft infection, amblyopia, and glaucoma continue to be serious concerns. In recent years both anterior and posterior lamellar keratoplasty techniques are being increasingly performed in pediatric eyes, which offer advantages in the form of lower risk of graft rejection. The timing of surgery, careful case selection, cautious intraoperative approach, and optimal postoperative management can improve the anatomical and functional outcome in difficult cases.

[Optical rehabilitation and pediatric ophthalmological care following keratoplasty for childhood corneal opacities]. / Optische Rehabilitation und kinderophthalmologische Betreuung nach Keratoplastik bei kindlichen Hornhauttrübungen.

BACKGROUND: The younger the children are at the time of corneal transplantation, the worse the survival prognosis of the graft. PREOPERATIVE CONSIDERATIONS: Preoperative considerations are significant in terms of accurate parental education, ensuring adherence to treatment and choosing the appropriate surgical time frame (amblyopia versus graft failure, compliance of the patient). Parental education must include the reduced visual prognosis in young children, exceptions being later acquired corneal pathologies such as inflammatory corneal scars (herpes) and keratoconus. POSTOPERATIVE CARE: A distinction must be made between morphological care after transplantation and refractive correction as well as treatment of amblyopia. The younger the children, the less favorable the prognosis for the transplant and the more often multiple examinations with anesthesia are necessary in order to detect complications, such as infiltrates or suture loosening at an early stage. Especially unilateral congenital pathologies often do not lead to a sufficient improvement of amblyopia (refractory amblyopia, poor compliance). CONCLUSION: The prognosis after keratoplasty in childhood is already partly decided by the careful evaluation of indications (no surgery of a sclerocornea) and the detailed and realistic clarification for the parents (cooperation with long-term ocular and systemic treatment even if the child has poor compliance, frequent check-ups, reduced chances of amblyopia treatment). The younger the child is at the time of transplantation, the more frequent are graft failure and the development of complications. Later manifesting diseases in older children (herpetic corneal scars, keratoconus) have a better prognosis.

Modified Nishida's procedure in a case of medial rectus hypoplasia.

Introduction: We report a case of large angle exotropia in a child with limitation of adduction in the left eye with a radiological finding of hypoplastic medial rectus. Methods: A 3- year- old male child presented with left eye large angle exotropia, left face turn, -4 adduction limitation and severe amblyopia. Orbital imaging revealed hypoplasia of the medial rectus and intraoperatively a thin medial rectus was noted. The surgical procedure planned was lateral rectus recession combined with Modified Nishida's technique in the left eye. In this technique the superior and inferior recti were transposed medially by inserting non-absorbable sutures in the sclera posteriorly, closer to the upper and lower borders of the medial rectus muscle. Result: There was improvement in adduction of left eye and reduction of original deviation following maximal lateral rectus recession and a modified Nishida's approach. The early and optimal correction of exotropia also improved the compliance to patching with subsequent gain in visual acuity of the amblyopic eye. Conclusion: Modified Nishida's technique has the advantage of no muscle splitting and no tenotomy, remains a less invasive surgical procedure to correct large deviations. The modification of placing the bellies closer to medial rectus augments the effect and further improves adduction in cases with severe limitation of adduction. This technique can thus be considered as a possible surgical approach in young children with large angle exotropia due to hypoplastic medial rectus.

Clinical characteristics and surgical approach in Duane retraction syndrome: a study of 691 patients.

PURPOSE: To evaluate the clinical findings of different types of Duane retraction syndrome (DRS). STUDY DESIGN: Retrospective. METHODS: This study was performed on 691 patients with DRS who underwent surgery. Clinical examinations included laterality, abnormal head posture (AHP), corrected distance visual acuity (CDVA), refractive error, amblyopia, deviation, overshoots, and type of surgery. RESULTS: The mean age of patients with DRS was 16.7 ± 12.5 (range 1.0-73) years. The patients included 396 (57.3%) women and 295 (42.7%) men (P < 0.001). DRS type I, was observed in 429 (62.1%), II in 168 (24.3%), III in 88 (12.7%) and IV in 6 (0.9%) patients. Unilateral DRS was observed OS in 628 (90.9%) [471 (%78.9) and OD in 157 (21.1%) eyes (P < 0.001)]. O ther clinical findings were AHP (n = 522, 78.1%), overshoot (n = 236, 34.2%) and amblyopia (n = 118, 17.1%). The prevalence of overshoot in types I, II, and III was 17.5% (75/429), 60.7% (102/168) and 64.8% (57/88), respectively (P < 0.001). The prevalence of amblyopia was significantly lower in patients with AHP (80/522, 15.3%) compared to patients with normal head posture (38/169, 22.5%) (P = 0.023). The mean angle of deviation in the primary position (PP) at distance was 21.7 ± 11.5 △ for esotropic group and 17.8 ± 12.4 △ for exotropic group. Sixty-two (9.0%) patients required second surgery for resolving residual misalignment (1.1 surgeries for each patient). CONCLUSIONS: About two-thirds of DRS patients had AHP, one-third had overshoots, and one-sixth had amblyopia. The results show that different types of DRS are associated with different epidemiological and clinical characteristics.

Effective connectivity anomalies in human amblyopia.

We investigate the effective connectivity in the lateral geniculate nucleus and visual cortex of humans with amblyopia. Six amblyopes participated in this study. Standard retinotopic mapping stimuli were used to define the boundaries of early visual cortical areas. We obtained fMRI time series from thalamic, striate and extrastriate cortical regions for the connectivity study. Thalamo-striate and striate-extrastriate networks were constructed based on known anatomical connections and the effective connectivities of these networks were assessed by means of a nonlinear system identification method. The effective connectivity of all networks studied was reduced when driven by the amblyopic eye, suggesting contrary to the current single-cell model of localized signal reduction, that a significant part of the amblyopic deficit is due to anomalous interactions between cells in disparate brain regions. The effective connectivity loss was unrelated to the fMRI loss but correlated with the degree of amblyopia (ipsilateral LGN to V1 connection), suggesting that it may be a more relevant measure. Feedforward and feedback connectivities were similarly affected. A hemispheric dependence was found for the thalamo-striate feedforward input that was not present for the feedback connection, suggesting that the reduced function of the LGN recently found in amblyopic humans may not be solely determined by the feedback influence from the cortex. Both ventral and dorsal connectivities were reduced.

Pediatric refractive surgery and its role in the treatment of amblyopia: meta-analysis of the peer-reviewed literature.

PURPOSE: To provide an overview of the visual outcomes after pediatric refractive surgery in anisometropic amblyopia and to analyze the relationship of these outcomes with age and type of refractive surgery. METHODS: Systematic searches in PubMed, Embase, and Web of Science databases without data restrictions and a search by surveillance of the literature regarding pediatric refractive surgery were performed. Only studies reporting individual data of pediatric cases (age 1 to 17 years) undergoing photorefractive keratectomy (PRK), laser epithelial keratomileusis (LASEK), and LASIK were included. A total of 15 articles including data from a total of 213 amblyopic eyes were considered: LASIK in 95 eyes and surface ablation in 118 eyes. Changes in uncorrected (UDVA) and corrected distance visual acuity (CDVA) were investigated as well as their relation with age and ablation type. RESULTS: A significant increase in logMAR UDVA and CDVA was found in the overall sample of amblyopic eyes after surgery (P<.001). A significant correlation was found between age and preoperative CDVA (r=0.34, P<.001) as well as between age and the change in CDVA after surgery (r=-0.38, P<.001). The change in UDVA was significantly superior for eyes undergoing surface ablation compared to those undergoing LASIK (P=.04). Corneal haze was the predominant complication, which was reported in 5.3% of LASIK cases and 8.5% of surface ablation cases. CONCLUSIONS: Laser refractive surgery is an effective option for improving the visual acuity in children with an amblyopic eye in association with anisometropia.