Isoametropic amblyopia due to high hyperopia in children.

PURPOSE: To identify children with isoametropic amblyopia due to moderate to high hyperopia and evaluate associated findings and visual acuity outcome. METHODS: Charts from two university's pediatric ophthalmology clinics were reviewed retrospectively. Healthy children with > or = +4.5 D spherical equivalent who did not have anisometropia > or = 1.5 D were selected for data collection. The charts of qualifying children with bilateral amblyopia (visual acuity of 20/40 or less) were further analyzed. RESULTS: Identified were 418 children with the above set of criteria for hyperopia; 36 of these children had isoametropic amblyopia (bilateral amblyopia). This gives an estimated prevalence of isoametropic amblyopia of 8.6% in children with at least 4.5 D of hyperopia in one or both eyes. The children with isoametropic amblyopia presented at a later age (5 years, 1 month) than the overall group of hyperopes (3 years, 5 months). Strabismus was less prevalent in this group (64%) than in the entire population of children with high hyperopia (81%). These children's amblyopia responded well to treatment with glasses, and patching in 13 (36%) cases. Surgical intervention for residual strabismus was necessary in very few cases (2 of 36, 5.5%). CONCLUSION: Children with hyperopia > or = 4.5 D have an increased risk of amblyopia and strabismus that further threatens their future visual function. Isoametropic amblyopia is a real risk in these children. Based on these results, hyperopic correction should be prescribed for children with > or = 4.5 D of hyperopia even if no strabismus or fixation preference is detected, to reduce this risk. Screening programs should also be in place to identify these children at an early age.     

Impact of amblyopia on vision at age 12 years: findings from a population-based study

AIMS: To report prevalence of amblyopia and long-term impact of its treatment on vision in a population-based sample of 12-year-old Australian children. METHODS: Logarithm of minimum angle of resolution (logMAR) visual acuity (VA) was measured in 2353 children (response rate 75.3%); visual impairment was defined as VA<6/12. Amblyopia was defined using various criteria of best-corrected VA, together with an amblyogenic factor and absence of significant organic pathology. Corroborative historical data on previous diagnosis and treatment were obtained from parental questionnaires. RESULTS: Forty-four children (1.9%) were diagnosed with amblyopia, unilateral in 40 and bilateral in four. Isolated anisometropia was the most frequent cause (41%), followed by strabismus (25%), combined anisometropia and strabismus (23%), and high ametropia (9%). Myopia, hyperopia, and astigmatism were present in 28, 51, and 44% of amblyopic children, respectively, compared to 12, 4, and 9% of non-amblyopic children. Mean best-corrected VA in amblyopic eyes was 44.5 logMAR letters (Snellen equivalent 6/9), range: 11-60 letters. Most children with amblyopia (84%) had been treated. Only 27% were visually impaired in their amblyopic eye. CONCLUSIONS: This report documents a low amblyopia prevalence in a population of 12-year-old Australian children. Amblyopic visual impairment was infrequent in this sample despite absence of mandatory vision screening.     

儿童远视性弱视与屈光状态的关系分析

目的探讨远视性弱视儿童远视度数与弱视、斜视的关系。方法对远视性弱视儿童300例（550眼）使用阿托品散瞳验光,检查结果进行统计学处理。结果远视性弱视儿童的远视度数由低至高依次为外斜视组、无斜视组、内斜视组。球镜度数越高,弱视程度越高,无斜视组中度弱视比轻度弱视球镜度数高,差异有高度显著性,轻度弱视比中度弱视的柱镜度数高,差异有显著性;重度弱视只有1例。内斜视组中度弱视比轻度弱视的球镜度数高,差异有高度显著性;重度弱视球镜度数比中度弱视低,与斜视和注视性质有关;外斜视组中度弱视比轻度弱视球镜度数高,差异有显著性。结论远视性弱视儿童远视度数与弱视程度有一定关系,但重度弱视还与视觉抑制和中心旁注视关系更为紧密;中高度远视是内斜视的主要原因;远视散光是弱视的重要原因。     

Prevalence and outcomes of childhood visual disorders

PURPOSE: This population-based study examines the prevalence of childhood visual disorders: amblyopia (strabismus, refractive errors) and organic disease. It also assesses treatment outcomes, visual impairment and residual amblyopia. METHODS: 1582 children were retrospectively analysed on treatment completion (age 8-9 years). Significant visual disorders included: esotropia, exotropia, anisometropia (hyperopia > or = 1.50DS, astigmatism > or = 1.00DC, myopia > or = 1.50DS), ametropia (hyperopia > or = 1.50DS, astigmatism > or = 1.0DC, myopia > or = 0.75DS) and organic defects. RESULTS: 198 children (12.5%) had a significant visual disorder: strabismus (3.98%), eso:exo rate 5:1, anisometropia (2.34%), ametropia (5.82%), organic defects (0.38%). Organic disease caused visual handicap (< 6/18 in better eye) in 0.13%. Amblyopic visual impairment (6/18; 6/24-6/60) occurred in 1.13%; 2.02% had residual amblyopia (6/12 or worse). CONCLUSIONS: Childhood visual disorders are a common problem. Unfavourable visual outcomes in esotropia are related to two sub-groups and particularly with poor concordance to treatment. Suggested strategies to improve outcomes include health promotion, an "Amblyopia Nurse" and a "Patch Club".     

Strabismus and amblyopia in bilateral Peters anomaly.

BACKGROUND: Peters anomaly is a rare form of anterior segment dysgenesis in which abnormal cleavage of the anterior chamber occurs at the end of the third week of gestation. We examined the prevalence of strabismus and amblyopia and analyzed predictive factors for their development, as well as the visual outcome and associated anomalies in patients with bilateral Peters anomaly. METHODS: Using a retrospective review, we identified 25 consecutive patients with bilateral Peters anomaly who were observed between August 1995 and February 2005. Ocular structural and systemic anomalies, amblyopia therapy, visual acuity, and binocular alignment at last visit were recorded. Fisher's exact test was used to identify any association between defined predictive factors and the development of strabismus. RESULTS: Mean follow-up time was 5.1 year (range, 0.5-21 years). Median age at presentation was 2.5 months (range, 1 day to 13 years). Penetrating keratoplasties were performed on 34 eyes in 20 patients. Final best-corrected visual acuity ranged from 20/25 to no light perception. Thirteen of 18 patients with recorded motility (72%) developed strabismus: esotropia (n = 7), exotropia (n = 5), and variable (n = 1); one also had dissociated vertical deviation. Patients with equal vision were either orthophoric (n = 4) or had intermittent esotropia (n = 1), whereas strabismus occurred in 100% of patients whose vision was asymmetric by more than 1.5 octaves. Asymmetric vision was the only statistically significant predictive factor for the development of strabismus (P = 0.002). Amblyopia treatment resulted in improved vision in 3 of 5 patients. CONCLUSION: Strabismus occurs frequently in bilateral Peters anomaly. Asymmetric vision, (because of ocular structural anomalies) postoperative complications, and amblyopia may predispose to strabismus. Despite ocular structural limitations, amblyopia therapy is recommended in the aggressive rehabilitation of these eyes.     

The Effect of Amblyopia Therapy on Ocular Alignment

PURPOSE: We sought to describe the change in ocular alignment at 2 years after treatment of amblyopia in children younger than 7 years of age at enrollment. METHODS: A randomized clinical trial of patching versus atropine for 6 months followed by standard clinical care for 18 months was conducted in 357 children with anisometropic, strabismic, or combined amblyopia (20/40-20/100) whose ages ranged from 3 to younger than 7 years at enrollment. Ocular alignment was evaluated at enrollment and after 2 years of follow-up. RESULTS: At enrollment when tested at distance fixation, 161 (45%) children were orthotropic, 91 (25%) had a microtropia (1-8 Delta), and 105 (29%) had a heterotropia >8 Delta. Of the 161 patients with no strabismus, similar proportions of patients initially assigned to the patching and atropine groups developed new strabismus by 2 years (18% vs. 16%, P = 0.84). Of these cases of new strabismus, only 2 patients in the patching group and 3 patients in the atropine group developed a deviation that was greater than 8 Delta. Microtropia at enrollment progressed to a deviation greater than 8 Delta with similar frequency in both treatment groups (13% vs. 15%, P = 1.00). Of the 105 patients with strabismus greater than 8 Delta at enrollment, 13% of those in the patching group and 16% of those in the atropine group improved to orthotropia without strabismus surgery. Strabismus surgery was performed in 32 patients during the 2-year study period. CONCLUSIONS: Patients who had amblyopia treatment with patching or atropine for 6 months followed by standard clinical care were found to have similar rates of deterioration and improvement of ocular alignment. When parents begin amblyopia treatment for children without strabismus, they should be warned of the possibility of development of strabismus, although it is most often a small angle deviation. Strabismus resolved after amblyopia therapy in some cases.     

Early-onset refractive accommodative esotropia.

INTRODUCTION: We studied the natural history of pure refractive accommodative esotropia after spectacle correction in patients with onset before 1 year old to determine whether their outcomes and characteristics were different from those of patients with more typical age at onset of refractive accommodative esotropia. METHODS: We retrospectively reviewed the charts of 17 children with onset of refractive accommodative esotropia before 1 year old. Records of 26 children with onset after 2 years old were reviewed as controls. RESULTS: The mean ages at diagnosis were 9 months and 48 months for the study and control groups, respectively. All 17 study patients and all 26 control patients were initially well aligned with spectacles at distance and near. Follow-up averaged 34 months for study patients and 41 months for control patients. Three study patients (17.6%) and 1 control patient (3.8%) had eventual deterioration and required strabismus surgery (P = .28). None of the study patients developed amblyopia, whereas 42% of control patients did (P = .001). Seven of 15 (47%) of the study patients with known birth history were born prematurely, whereas only 3 of 24 (12%) control patients were born prematurely (P = .03). CONCLUSIONS: Refractive accommodative esotropia was diagnosed at as early as and age 4 months. Prematurity appeared to be a risk factor. Amblyopia was not detected in any patient with early-onset refractive accommodative esotropia. Treatment with full hyperopic spectacle correction led to long-term stable alignment, with relatively few patients requiring surgery.     

Clinical features predictive of successfully weaning from spectacles those children with accommodative esotropia.

PURPOSE: It has been reported that most children with accommodative esotropia are not able to discontinue spectacle wear as they become older. We conducted a prospective study to determine which factors are predictive of successfully weaning children from spectacles. METHODS: Beginning in 1995, children with fully accommodative esotropia with a baseline refractive error of + 1.50 to + 5.00 diopters (D) were gradually weaned from their hyperopic correction. Patients with amblyopia or who had previously undergone strabismus surgery were excluded. Children were weaned in 0.50 D increments until spectacles were discontinued or they developed esotropia, asthenopia, or decreased vision. A multivariate analysis was performed to assess the association between successful weaning and various clinical characteristics. RESULTS: Twelve of 20 children (60%) were successfully weaned from spectacles. Spectacles were prescribed at a mean age of 4.2 +/- 1.5 years, and weaning was initiated at a mean age of 8.0 +/- 1.1 years. The spherical equivalent of the least hyperopic eye when spectacles were prescribed was 2.99 +/- 1.06 D. The clinical characteristic most clearly associated with successful weaning was the refractive error at the time glasses were prescribed. Whereas 10 of 11 (91%) patients with < 3 D of hyperopia were weaned from spectacles, only 2 of 9 (22%) patients with 3 to 5 D of hyperopia were successfully weaned from their spectacles (P =.005). CONCLUSIONS: Many children with fully accommodative esotropia can be weaned out of spectacles during the grade school years. The degree of baseline hyperopia appears to be one of the best predictors of success.     

Ocular status of boys with fragile X syndrome: a prospective study.

PURPOSE: The purpose of this study was to determine whether the high rates of ocular problems described in previous retrospective reports of individuals with fragile X syndrome were present in a prospective sample of young boys. Fragile X syndrome is currently considered the leading hereditary cause of mental retardation, with prevalence estimates of 1:2500 to 1:5000 males. METHODS: Forty-eight boys with fragile X syndrome between the ages of 2.5 and 11 years were evaluated for ocular abnormalities. They received complete ophthalmic evaluations including assessment of visual acuity, cycloplegic refraction, ocular motility assessment, and dilated fundus examination. RESULTS: Approximately 25% of the children had clinically significant ocular findings that included refractive errors (17%, primarily hyperopia and astigmatism) and strabismus (8%). Of the 42 children with quantifiable visual acuities, only 1 child, with diagnoses of nystagmus and hyperopia, had a Snellen visual acuity that was not within normal limits for his age. Three of the 5 children with gross measures of visual acuity had clinically significant findings: 2 had hyperopia greater than 3.5 diopters and 1 had esotropia. The other 2 children with gross measures of acuity and the 1 child without visual acuity assessment had cycloplegic refractions of +1.25 to +1.5 and ocular motility appeared normal. CONCLUSIONS: These results suggest that previous reports of high rates of vision problems, particularly strabismus, in boys with fragile X syndrome may have resulted from selection bias. Although we did observe a higher prevalence of strabismus than that found in the general population (8% vs 0.5% to 1%), the proportion of children having strabismus in our sample was much smaller than that reported in other studies of children with fragile X syndrome (30% to 40%). However, 17% of the sample did have significant refractive errors. In addition to evaluating the ocular motility of children with fragile X syndrome, cycloplegic refraction should also be performed to determine whether refractive problems are present.     

Refraction as a basis for screening children for squint and amblyopia.

+2-00 to +2-75 dioptres of spherical hypermetropia in the more emmetropic of a pair of eyes is significantly associated with esotropia (P less than 0-001) and the presence of amblyopia (P less than 0-01). Anisometropia is not significantly associated with esotropia (P = 0-31) unless there is spherical hypermetropia of +2-00 dioptres or more in the more emmetropic eye (P less than 0-001). Hypermetropic anisometropia of +1-00 DS or +1-00 D.Cyl. is associated with the presence of amblyopia (P less than 0-001). In the absence of esotropia there is also a significant association between the amount of anisometropia and the initial depth of amblyopia (P less than 0-01). The additional presence of esotropia increases the depth of amblyopia further (P less than 0-05) but not the incidence of amblyopia (P greater than 0-30). The level of significance of the association of refractive errors with squint/amblyopia was itself significantly higher (P less than 0-01) than that between a family history of squint or "lazy eye" on the one hand and squint and/or amblyopia on the other hand. 72 +/- 3% of all cases of esotropia and/or amblyopia in this sample of children had a refractive error of +2-00 DS or more spherical hypermetropia in the more emmetropic eye, or +1-00 D. or more spherical or cylindrical anisometropia. Since there is a close association between the refraction and how, when, and whether a child presents with squint and/or amblyopia, it would seem reasonable to reconsider refraction as a basis for screening young children for visual defects.     

儿童部分调节性内斜视的治疗及调整缝线在手术中的应用

目的 探讨儿童部分调节性内斜视的术前治疗、手术时机与手术量以及调整缝线在治疗中的应用。设计 回顾性病例系列。研究对象 北京儿童医院眼科接受手术治疗的部分调节性内斜视患者30例。方法 对手术治疗的部分调节性内斜视患者的临床资料进行回顾性分析。患儿术前矫正屈光异常,观察斜视度稳定,并予适当弱视治疗,在双眼视力相当的情况下进行手术,按照裸眼和戴镜斜视度的平均值设计手术量。术中常规使用调整缝线技术,术后早期依据眼位情况决定是否需要调整。术后随访6~15个月。观察眼位及双眼视功能。主要指标 术后眼位、双眼视功能、眼位调整情况。结果 有3例患儿进行了眼位调整,均为过矫,避免了二次手术。末次随访时30例患者中26例（87%）眼位在正位~+8△之间,4例（13%）眼位+10△~+15△。术前能合作行双眼视功能检查者19例,有双眼视功能者2例（11%）。末次随访时能合作双眼视功能检查者21例,有双眼视功能者15例（71%）。结论  内斜视伴有调节因素时应及时全矫配镜,在残余斜视度稳定、双眼矫正视力基本相当后应尽早手术。手术设计根据戴镜与裸眼视近的平均斜视度,调整缝线有助于保证术后早期的眼位满意,降低了二次手术的风险。（眼科, 2013,22: 121-123）     

Prevalence of Amblyopia and Strabismus in a Population of 7th-Grade Junior High School Students in Central China: The Anyang Childhood Eye Study (ACES)

Purpose: To determine the prevalence of amblyopia and strabismus in 7th-grade junior high school students in central China.

Methods: Using stratified cluster sampling, 2363 7th-grade students were recruited from four junior high schools in Anyang city into the cross-sectional Anyang Childhood Eye Study (ACES). All students underwent visual acuity (VA), cycloplegic autorefraction, cover test, and ocular movement examinations. Uncorrected VA and best-corrected VA (BCVA) were measured with a logarithm of the minimum angle of resolution (logMAR) chart. Cycloplegic autorefraction was performed after administration of 1.0% cyclopentolate and Mydrin-P. Strabismus was defined as heterotropia at near or distance fixation. Amblyopia was defined as BCVA≤0.1 logMAR units in one or both eyes, without ocular pathology in either eye.

Results: Of the 2363 eligible students, 2260 (95.6%) completed all examinations. The mean age of the students was 12.4?±?0.6 years. Amblyopia was present in 52 students (2.5%), of whom 33 (63.5%) had unilateral and 19 (36.6%) had bilateral amblyopia. Of those with unilateral amblyopia, 18 (54.5 %) had anisometropia and 7 (21.2%) had strabismus. Of those with bilateral amblyopia, 6 (31.6%) had significant refractive error. Strabismus was present in 108 students (5.0%), of whom 2 (1.9%) had esotropia, 102 (94.4%) had exotropia, 3 (2.8%) had vertical strabismus, and 1 (0.9%) had microstrabismus. Of the 108 students with strabismus, 9 (8.3%) had amblyopia.

Conclusion: The cross-sectional ACES which examined the prevalence of amblyopia and strabismus in 7th-grade students in central China revealed the prevalence of strabismus, particularly the proportion of exotropia, to be higher than previously reported.     

Infantile esotropia in very low birth weight (VLBW) children

VLBW children are known to have a high frequency of early onset strabismus, which is related to the high prevalence of pre- and perinatal cerebral disturbances reported in these children. It is unknown if the early onset strabismus in VLBW children has the characteristics of infantile esotropia. If so, then (acquired) cerebral damage may play an important role in the origin of this type of strabismus. For this reason, the charts of 265 VLBW children were retrospectively reviewed. Strabismus was present in 55 (20.7%) children. Mean follow-up was 75 weeks, with 29.8% of the children having a follow-up of less then 6 months. Only 5 children (1.9%) with characteristics of infantile esotropia could be identified. Another 8 children (3.0%) possibly had infantile esotropia, but follow-up had been too infrequent during the first year of life to determine the time of onset of strabismus precisely. The other 42 children with strabismus all had ophthalmological disorders (i.e. ROP, optic nerve atrophy, cortical blindness) explaining early disruption of binocular visual development. Therefore, VLBW children are at risk for early onset strabismus. However, infantile esotropia is not typical for VLBW children and may be an indication that early acquired cerebral damage does not play an important role in the pathogenesis of infantile esotropia.     

Risk of strabismus and ambylopia in children with hydrocephalus

Objectives The present study was undertaken to determine the risk of strabismus and ambylopia in children who underwent operation for hydrocephalus and to compare our results with those in previous studies. Methods Full orthoptic and ophthalmological examinations, including cycloplegic refraction, were performed in all subjects. Results Ten of 25 patients (40%) were found to have manifest squint. Four of these had esotropia and six had exotropia. No paretic squint or alphabetic pattern strabismus was determined. Refraction measurements revealed amblyogenic refractive errors (significant refractive errors that cause amblyopia) in five of the 25 (20%) patients in this study. Strabismus and the risk of amblyopia were found to be significantly higher in patients who experienced shunt revision than those who had not (P<0.05). Conclusion Amblyopia, strabismus, and other acquired defects in the visual system related to hydrocephalus should be closely monitored and treated when indicated. Regular ophthalmic supervision will provide and help to maintain the best possible standard of vision in children with hydrocephalus.     

Age at strabismus diagnosis in an incidence cohort of children

PURPOSE: To compare the age at diagnosis of children with esotropia, exotropia, and hypertropia. DESIGN: Retrospective, population-based cohort study. METHODS: The medical records of all Olmsted County, Minnesota, residents < 19 years diagnosed with esotropia, exotropia, or hypertropia from January 1, 1985 through December 31, 1994 were reviewed. RESULTS: The median age at diagnosis of esotropia (n = 380), exotropia (n = 205), and hypertropia (n = 42) was 3.1 years, 7.2 years, and 6.1 years, respectively (P = .001). In the first six years of life, esotropia had the highest incidence and was more likely to occur than either exotropia or hypertropia; exotropia predominated between age seven and 12 years; and each form was similarly likely to occur between 13 and 18 years of age (P = .001). CONCLUSIONS: The age at diagnosis was significantly different for the various forms of strabismus in this population. Esotropia is the most common form in the first six years of life; beyond this age exotropia predominates until the teenage years when the three forms have a similar but decreased incidence.     

Amblyopia and Strabismus in Iranian Schoolchildren,Mashhad

Purpose: To determine the prevalence of amblyopia and strabismus among the population of schoolchildren Mashhad, Iran.

Materials and Methods: In a cross-sectional study with cluster sampling, 2510 schoolchildren were selected from schools of district 1 in Mashhad. Uncorrected visual acuity (UCVA) and best corrected visual acuity (BCVA) were recorded for each participant. Amblyopia was distinguished as a reduction of BCVA to 20/30 or less in one eye or 2-line interocular optotype acuity differences in the absence of pathological causes.

Results: Of the 2510 selected schoolchildren, 2150 participated (response rate, 85.6%). The mean (± standard deviation) age of the participants was 13.2?±?3.2 (range, 6-21) years. The prevalence of amblyopia was 1.9% (95% CI: 0.94-2.90); 2.1% (95% CI: 0.10-3.16) in girls and 1.7% (95% CI: 0.30-3.12) in boys (P?=?0.6). Among myopic, hyperopic, and astigmatic students, 3.7%, 27.8%, and 6.5% had amblyopia, respectively (P<0.001). The causes of amblyopia were anisometropia in 65.9%, strabismus in 24.4%, and isoametropia in 9.8%. The prevalence of strabismus was 3.1% (95% CI, 1.3% to 4.3%); 4.2% (95% CI, 3.05 to 5.7%) in girls, and 2.0% (1.3% to 2.9%) in boys (P?=?0.0011). Strabismus was significantly more prevalent among hyperopic students (7.9%) compared with myopic ones (3.7%).

Conclusion: Results of the present study indicate that the prevalence rate of amblyopia was in the mid-range of other studies, and the prevalence of strabismus was relatively high. Since refractive errors, especially hyperopia, are responsible for some cases of strabismus.     

Isoametropic amblyopia in highly hyperopic children

PURPOSE: The purpose of this study was to evaluate the visual outcome and associated findings in isoametropic amblyopia due to high hyperopia. METHODS: Children with > or = 5 D spherical equivalent hyperopia and < or = 1.5 D anisometropia and < or = 1.5 D cylinder in both eyes were selected. Data were collected on the magnitude of spherical equivalent hyperopia, corrected visual acuity (VA) with the Snellen or Tumbling E charts, age at correction, duration of correction, ocular motility and strabismus. Children who had VA of < or = 0.4 in both eyes were defined as having isoametropic amblyopia. Associations between isoametropic amblyopia and factors affecting VA were analysed. RESULTS: A total of 160 children met the criteria. The mean follow-up was 55.8 months. In all, 31 of the children had isoametropic amblyopia. The mean age at presentation was significantly higher (5.5 years versus 4.1 years; p < 0.05) and strabismus was significantly less prevalent (p = 0.001) in the isoametropic amblyopes than in the high hyperopia group as a whole. A total of 83.9% of the isoametropic amblyopes had best corrected VA > 0.5 at the last visit. The duration of optical correction was positively correlated with the last recorded VA measurement. CONCLUSION: Isoametropic amblyopia is not rare among highly hyperopic children. Visual acuity improves satisfactorily with spectacle correction. The duration of optical correction seems to be an important factor in visual prognosis.     

Refraction changes in children developing convergent or divergent strabismus.

Strabismus and amblyopia were studied in a cohort of children born in 1979 or 1980 in the area of Västerås, Sweden. Forty percent of the children had participated in a voluntary eye examination at 1 year of age. All children diagnosed as strabismic and/or amblyopic between 1979 and 1988 at any of the three eye clinics in the area were included in this study. Strabismic cases were mostly detected by the parents while microstrabismus and straight eye amblyopia were found at the general 4 years of age screening at children''s health centres. In 57 cases with (n = 31) and without amblyopia (n = 41) it was possible to obtain several refraction values between 1 and 6 years of age. In this study we concentrated on manifest esotropia and exotropia. The aim of the study was to describe changes of refraction before and after onset of strabismus and to establish risk indicators that identified populations at risk of developing strabismus. We found that patients with esotropia show a more pronounced hypermetropia than exotropic cases at the time of detection of strabismus. This difference becomes more definite over time, since hypermetropia increased in the deviating eye in the esotropic cases while refractive errors remained stationary in most of the exotropic eyes. It was also apparent that anisometropia frequently developed after onset of strabismus in esotropic cases in contrast to exotropic cases. An increasing refractive error in the deviating esotropic eye could be combined with an emmetropisation of the fixating eye.     

The Prevalence of Strabismus and Associated Risk Factors in a Southeastern Region of Brazil

Purpose: To determine the prevalence of strabismus and associated risk factors in southeastern Brazil. Methods: A cross-sectional, population-based study using a systematic sample from nine municipalities in a southeastern region of Brazil composed of 1852 individuals aged ≥1 and ≤12 years old was done. Visual acuity (VA), ocular alignment, and refractive error (RE) were evaluated. Strabismic individuals (strabismus group) were compared to orthotropic individuals (orthotropic group) to analyze risk factors linked to heterotropias. Results: Prevalence of strabismus was 0.81% in this population. In the strabismus group, we found 40% with hyperopia, 6.67% with astigmatism, 3.33% with myopia, 6.67% with amblyopia, and 8.33% with moderate anisometropia. In the orthotropic group, 6.85% had hyperopia, 18.12% astigmatism, 14.82% myopia, 0.19% amblyopia, and 4.37% moderate anisometropia. Conclusion: The prevalence of strabismus in southeastern Brazil was 0.81%. Strabismic individuals had more hyperopia. Amblyopia and moderate anisometropia were associated with strabismus.     

中山市学龄前儿童斜视和弱视调查研究

目的:观察中山市学龄前儿童斜视和弱视调查情况及解决对策.方法:随机抽取中山市市区及镇区34所幼儿园3~7岁学龄前儿童7291名14582眼进行屈光筛查,对于屈光异常者采用浓度为10g/L阿托品眼膏散瞳检影,测定儿童的矫正视力,确定弱视.采用检影验光测定屈光性弱视,采用角膜映光法、交替遮盖法等完成斜视的筛查,分析中山市学龄前儿童的斜视、弱视情况.结果:入选的7291名学龄前儿童中有687名屈光异常,异常率为9.42%,236名弱视,检出率为3.24%,13名斜视,检出率为0.18%.3~<5岁及5~7岁年龄段屈光异常、弱视及斜视检出率比较差异无统计学意义(P>0.05);236名弱视中215名屈光不正性弱视,占总弱视的91.10%;13名儿童斜视性弱视,其中8名共同性内斜视,5名共同性外斜视;8名形觉剥夺性弱视,斜视性弱视与形觉剥夺性弱视相比差异有统计学意义(P<0.05);236名中3~<5岁轻度弱视儿童构成比高于5~7岁,差异有统计学意义(P<0.05),3~<5岁中度和重度弱视儿童构成比低于5~7岁,差异有统计学意义(P<0.05).结论:中山市学龄前儿童斜视弱视发生率相对较高,应该早期筛查,对于异常儿童尽早采取有效的措施进行干预,提高儿童视力.