The causal effect of obesity on concomitant exotropia: A lifecourse Mendelian randomization study.

Obesity is now a significant global public health issue. Limited understanding exists regarding the association between obesity and concomitant exotropia. Our objective was to identify the causal relationship between lifecourse obesity, including birth weight, childhood body mass index (BMI), and adult BMI, and the risk of concomitant exotropia. We used a two-sample Mendelian randomization (MR) strategy to examine the causal relationship with inverse-variance weighted method as the primary MR analysis. We carried out sensitivity analyses to evaluate the accuracy and robustness of our findings. Also, we performed reverse-direction MR analysis to eliminate the possibility of reverse causality. Childhood BMI, as opposed to birth weight or adult BMI, had a significant impact on the risk of concomitant exotropia (odds ratio = 1.40, 95% confidence interval (CI): 1.08-1.81, P = .01). This significance persisted even after accounting for birth weight and adult BMI using multivariable MR analysis (odds ratio = 1.35, 95% CI: 1.04-1.75, P = .02). There was no significant heterogeneity or pleiotropy observed in sensitivity analyses (P > .05). Multivariable MR analysis further confirmed the absence of pleiotropic effects of some risk factors including prematurity, maternal smoking around birth and refractive error. Reverse causality did not affect the causal relationship (beta = -0.0244, 95% CI: -0.0545 to 0.0056, P = .11). Genetic predisposition to higher childhood BMI was found to be causally linked to an increased risk of concomitant exotropia.

The distribution characteristics of strabismus surgery types in a tertiary hospital in the Central Plains region during the COVID-19 epidemic.

OBJECTIVE: This study aimed to analyze the distribution of different types of strabismus surgery in a tertiary hospital in Central China during the three-year period of the COVID-19 pandemic. METHODS: A retrospective analysis was conducted on the clinical data of strabismus patients who underwent surgery and were admitted to the Department of Strabismus and Pediatric Ophthalmology at the First Affiliated Hospital of Zhengzhou University between January 2020 and December 2022. RESULTS: A total of 3939 strabismus surgery patients were collected, including 1357 in 2020, 1451 in 2021, and 1131 in 2022. The number of surgeries decreased significantly in February 2020, August 2021, and November and December 2022. Patients aged 0-6 years accounted for 37% of the total number of strabismus surgery patientsr. The majority (60%) of all strabismus surgery patients were diagnosed with exotropia, with intermittent exotropia accounting for the highest proportion (53%). There was no statistically significant difference in the proportion of intermittent exotropia and constant exotropia during the three-year period (χ2 = 2.642, P = 0.267 and χ2 = 3.012, P = 0.221, respectively). Among patients with intermittent exotropia, insufficient convergence type was the most common form of strabismus (accounting for over 70%). Non-accommodative esotropia accounted for more than 50% of all internal strabismus cases. CONCLUSION: During the period from 2020 to 2022, the total number of strabismus surgeries in our hospital did not show significant fluctuations, but there was a noticeable decrease in the number of surgeries during months affected by the pandemic. Exotropia accounted for the highest proportion among strabismus surgery patients. Intermittent exotropia was the most common type among patients undergoing surgery for exotropia, and the most prevalent subtype was the insufficient convergence type. The age distribution of patients varied in different months, with a concentration of surgeries for strabismus patients in the 7-12 years old age group during the months of July and August each year.

Clinical profile of childhood exotropia in a tertiary eye care center in North India.

PURPOSE: To identify different types of exotropia in children less than 16 years and their clinical presentation. The secondary objective is to identify the age of onset, age of presentation, birth history, and ocular and systemic associations as well as to evaluate their motor and sensory status. METHODS: This hospital-based descriptive observational study was conducted from September 2018 to December 2019. Patients with a clinical diagnosis of exotropia of age less than 16 years, and exotropia of ≥ 10 PD were included in the study. Data were collected using a structured proforma. All statistical calculations were performed using Microsoft Excel Office version 2016 and R version 4.0.2. RESULTS: Two hundred eighty-six (286) consecutive children with exotropia were analyzed. Intermittent exotropia (72%) was the most common form of exotropia, followed by exotropia with a neurological association (11%), infantile (8%), sensory (6%), restrictive (2%), and paralytic (1%) types. Exotropia with neurological association had a significantly earlier age of presentation (median = 42months) as compared to other types (P = 0.039). CONCLUSION: We recorded a huge amount of cases of exotropia associated with neurological abnormalities and this group of patients had significantly more number of preterm and low birth weight children. This study has its limitations as it is not a population-based study and prevalence rates could not be calculated.

Refractive Profile of Surgical Patients with Intermittent Exotropia: A Large-Sample Cross-Sectional Study in Southern China.

PURPOSE: To describe the refractive profile of surgical patients with intermittent exotropia (IXT) residing in southern China. METHODS: Medical records of patients who received strabismus surgery between June 2014 and August 2020 were retrospectively reviewed. Clinical data, including age, sex, refractive errors, preoperative angle of deviation, types of exotropia, accommodative convergence to accommodation ratio (AC/A ratio) and stereopsis, were investigated. RESULTS: A total of 2250 patients were included, and 93.6% of patients were younger than 30 years of age. The mean angle of exodeviation was 37.0 ± 14.7 prism degree (PD) and 37.5 ± 15.8 PD at distance and near, respectively. Mean spherical equivalent refraction (SER) values were -0.7 ± 2.4 D and -0.8 ± 2.5 D in the dominant eye and nondominant eye, respectively. Significant differences in SER were observed between the dominant eye and nondominant eye among children at 6 years old or younger. The percentage of myopia increased from 11.0% in children (≤6 years old) to 77.9% in teenagers (13-18 years of age). Significant positive associations between the magnitude of exodeviation and the magnitude of myopia were observed (p < 0.0001). Patients with convergence insufficiency type IXT (p < 0.0001) or AC/A < 2 (p < 0.05) showed a greater magnitude of myopia. The mild hyperopia group included a larger proportion of subjects showing a certain degree of stereopsis (p < 0.05). CONCLUSIONS: Myopia was present in more than half of our patients (51.2%), which is much higher than the percentage in the general population of southern China. Patients with convergence insufficiency, an AC/A ratio < 2, or a larger angle of deviation tended to have a greater magnitude of myopia.

Comparison of Myopia Progression among Myopic Children with Intermittent Exotropia and No Strabismus.

SIGNIFICANCE: Myopia is a highly prevalent condition in the pediatric population that is commonly comorbid with intermittent exotropia. Our study found a trend toward significance in the reduction of myopia progression with strabismus correction surgery. Further investigations characterizing the interaction between myopia and strabismus may help inform future management guidelines. PURPOSE: This study describes and compares myopic progression in the pediatric population with and without intermittent exotropia and its interaction with corrective strabismus surgery. METHODS: This study analyzed a retrospective cohort of 1239 pediatric myopic patients who were evaluated by pediatric ophthalmologists and optometrists at a tertiary care center from 2012 to 2020. The main outcome measures were the trends in refractive error over time in those with and without intermittent exotropia as well as trends in those who did and did not undergo strabismus surgery. RESULTS: A total of 275 patients (22%) were identified to have intermittent exotropia, and 12 (4.4%) from this group underwent surgical correction in the study period. No statistically significant difference was identified in myopic progression between those with intermittent exotropia and those without strabismus, and no difference was found in mean annual spherical equivalent change between intermittent exotropia patients who did not undergo surgery compared with those who did. CONCLUSIONS: Pediatric myopic patients generally experience progression in the condition for several years independent of concurrent intermittent exotropia. Corrective strabismus surgery was not found to alter the natural history of myopia in children, although a reduction in myopic progression in surgically treated patients trended toward significance. Increases in the prevalence of different treatment strategies will necessitate further studies to determine best practices for this population.

Divergence excess and basic exotropia types of intermittent exotropia: a major review. Part 1: prevalence, classification, risk factors, natural history and clinical characteristics.

INTRODUCTION: Intermittent exotropia (IXT) is a common form of strabismus. It is an outward deviation of one eye typically when viewing at distance. Symptoms include, but are not limited to double vision, eyes feeling tired, excessive blinking, and reduced quality of life. Its clinical characteristics are distinctive from other types of strabismus. This paper provides a comprehensive review of prevalence, classification, risk factors, natural history and clinical characteristics of the divergence excess and basic exotropia types of IXT. METHODS: Search strategies involving combination of keywords including intermittent exotropia, exotropia, divergences excess, basic exotropia, prevalence, incidence, classification, terminology, risk factor, natural history, observation, angle of deviation, control, control score, symptom, quality of life, suppression, anomalous retinal correspondence, AC/A, accommodative convergence/accommodation, accommodative convergence, convergence, accommodation, vergence, incomitance and vertical were used in Medline. All English articles from 1900/01/01 to 2020/09/01 were reviewed. The reference list of the identified article was also checked for additional relevant article. Studies focused on animal model or strabismus associated with neurologic disorder or injury were excluded. RESULTS: The estimated prevalence of IXT in children ranges from 0.1% to 3.7%. Hypoxia at birth and being female are potential risk factors of IXT. Using validated measures of control, multicenter prospective studies showed that the rate of conversion from IXT to constant exotropia is low. The angle of deviation is the most reported outcome measure in studies of IXT. It is often used to represent the severity of the condition and has been suggested as one of the four core outcomes for studies of the surgical management of IXT. Control of exodeviation is one of the four suggested core outcomes for study of surgery of IXT and is considered the main parameter of disease severity. Several validated tools for quality of life score are available to evaluate the subjective severity of IXT. DISCUSSION: We reviewed the prevalence, classification, risk factors, natural history and clinical characteristics of the divergence excess and basic exotropia types of IXT. Further research into these areas, especially its clinical characteristics (e.g. suppression, dual retinal correspondence), will increase our understanding of this condition and potentially lead to better management of this common form of strabismus.

A retrospective study of strabismus surgery in a tertiary eye hospital in the Chaoshan area in China from 2014 to 2020.

BACKGROUND: To investigate the distribution pattern of strabismus surgery at an eye center in southern China. METHODS: The data of all patients who underwent strabismus surgery at the Joint Shantou International Eye Center of Shantou University /Chinese University of Hong Kong from 2014 to 2020 were retrospectively analyzed. The type of strabismus and its relationship with age and sex were analyzed, and the trend in the number of strabismus surgeries was observed. RESULTS: The data of 4640 patients included a total of 5,282 surgeries. Exotropia surgery was the most common, accounting for 54.0% of all strabismus surgeries, which tended to increase over time, but not significantly (P = 0.109). Constant exotropia was the most common exotropia, but its proportion decreased year by year. The next most common was intermittent exotropia. The percentage of surgeries for intermittent exotropia increased from 2016 to 2020. Surgery for esotropia accounted for 22.1% of all strabismus surgeries and became significantly less common from 2016 to 2020 (P < 0.01). Among patients with intermittent or constant exotropia, the proportion of patients younger than 12 years who underwent surgical intervention increased yearly, while this proportion amoung patients older 12 years old with constant exotropia decreased yearly. CONCLUSION: Among exotropia surgeries, surgery for constant exotropia was the most common but decreased in prevalence annually. Children under 12 years old were the most affected population.

Binocular vision disorders in a geriatric population.

CLINICAL RELEVANCE: A population-based epidemiological survey is important to help establish the frequency of binocular vision disorders in a geriatric population. Such data will be useful to clinicians and help guide diagnostic testing for this age group. BACKGROUND: To determine the prevalence of binocular vision disorders and their associations with age and sex in the geriatric population. METHODS: This report is a part of the Tehran Geriatric Eye study (TGES); a population-based cross-sectional study conducted on residents over 60 years of age in Tehran, Iran, using random stratified cluster sampling. A total of 165 clusters were selected (proportionally to size) from 22 strata of Tehran city. All participants underwent a complete ocular examination including the measurement of visual acuity, refraction, unilateral and alternating cover tests, and the Worth 4-dot suppression test. Strabismus was defined as the presence of constant unilateral or alternating esotropia or exotropia at either near (40 cm) or far (6 m). Distance and near exophoria were defined as more than 3Δ and 9Δ of exophoria at 6 m and 40 cm, respectively. Distance and near esophoria were defined as more than 1Δ and any amount of esophoria at 6 m and 40 cm, respectively. RESULTS: Statistical analysis was performed on the data of 2,227 participants. The mean age of the participants was 66.6 ± 5.4 years and 59.4% were female. The prevalence of distance exophoria, esophoria, and hyperphoria was 8.9%, 0.34%, and 0.29%, respectively. The prevalence of near exophoria, esophoria, and hyperphoria was 32.4%, 0.61%, and 0.37%, respectively. The prevalence of distance exotropia and esotropia was 1.3% and 0.63%, respectively. The prevalence of near exotropia and esotropia was 4.6% and 0.59%, respectively. CONCLUSION: Non-strabismic binocular vision disorders were prevalent in an elderly population. Exo deviations were more prevalent than eso deviations.

Prevalence of strabismus and its risk factors among school aged children: The Hong Kong Children Eye Study.

The study aims to determine the prevalence of strabismus and its risk factors among school children in Hong Kong. This is a cross-sectional study involving 6-8 year old children from different districts in Hong Kong. 4273 children received comprehensive ophthalmological examination, cycloplegic auto-refraction, best corrected visual acuity (BCVA), anterior segment examination, cover/uncover test, ocular motility, and fundus examination. Demographic information, pre- and post- natal background, parental smoking status, and family history of strabismus were obtained through questionnaires. Strabismus was found among 133 children (3.11%, 95% CI 2.59-3.63%), including 117 (2.74%) exotropia and 12 (0.28%) esotropia cases (exotropia-esotropia ratio: 9.75:1). There was no significant difference in prevalence across age (6-8 years) and gender. Multivariate analysis revealed associations of strabismus with myopia (≤ - 1.00D; OR 1.61; 95% CI 1.03-2.52; P = 0.037) hyperopia (≥ + 2.00D; OR 2.49; 95% CI 1.42-4.39; P = 0.002), astigmatism (≥ + 2.00D; OR 2.32; 95% CI 1.36-3.94; P = 0.002), and anisometropia (≥ 2.00D; OR 3.21; 95% CI 1.36-7.55; P = 0.008). Other risk factors for strabismus included maternal smoking during pregnancy (OR 4.21; 95% CI 1.80-9.81; P = 0.001), family history of strabismus (OR 6.36; 95% CI 2.78-14.50, P < 0.0001) and advanced maternal age at childbirth (> 35 years; OR 1.65; CI 1.09-2.49, P = 0.018). The prevalence of strabismus among children aged 6-8 years in Hong Kong is 3.11%. Refractive errors, family history of strabismus and maternal smoking history during pregnancy are risk factors. Early correction of refractive errors and avoidance of maternal smoking during pregnancy are potentially helpful in preventing strabismus.

Effects of prolonged use of virtual reality smartphone-based head-mounted display on visual parameters: a randomised controlled trial.

We investigated the effects of using a virtual reality smartphone-based head-mounted display (VR SHMD) device for 2 h on visual parameters. Fifty-eight healthy volunteers were recruited. The participants played games using VR SHMD or smartphones for 2 h on different days. Visual parameters including refraction, accommodation, convergence, stereopsis, and ocular alignment and measured choroidal thickness before and after the use of VR SHMD or smartphones were investigated. Subjective symptoms were assessed using questionnaires. We analyzed the differences in visual parameters before and after the use of VR SHMD or smartphones and correlations between baseline visual parameters and those after the use of the devices. Significant changes were observed in near-point convergence and accommodation, exophoric deviation, stereopsis, and accommodative lag after the use of VR SHMD but not after that of smartphones. The subjective discomfort associated with dry eye and neurologic symptoms were more severe in the VR group than in the smartphone group. There were no significant changes in refraction and choroidal thickness after the use of either of the two devices. The poorer the participants' accommodation and convergence ability the greater the resistance to changes in these visual parameters, and participants with a large exophoria were more prone to worsening of exophoria than those with a small exophoria.

Outcomes of intermittent exotropia surgery.

PURPOSE: To study the epidemiological and clinical characteristics of intermittent exotropia and to describe our therapeutic choices as well as their results and prognostic factors. MATERIALS AND METHODS: This was a retrospective study including 57 cases of intermittent exotropia. All patients underwent a complete ophthalmological examination with a sensory-motor assessment. Surgery was performed by the same surgeon, and the vertical component was addressed surgically at the same time as the exotropia. Statistical analysis was performed using SPSS software version 21.0. RESULTS: Our patients were classified as basic exotropia in 46 cases (80.7%), divergence excess in eight cases (14.1%), and convergence insufficiency in three cases (5.2%). Amblyopia was found in 26% of cases. The preoperative maximum angle of deviation was 36.5DP±9.1DS and a vertical component was found in 16 patients (28%). The most common was V pattern (8 patients). The mean age at the time of surgery was 14.8 years old. After a single surgery, we obtained motor success in 78.9% of the patients. Three patients were re-operated, with an overall motor success of 84.2%. CONCLUSIONS: Motor and sensory success may be achieved in intermittent exotropia. Rigorous, early management is necessary, even if tropic episodes are still rare. The rate of early consultation among children is still low in our country; thus, a national strabismus screening program must be established to obtain the best results.

Effect of age on reoperation rate in children undergoing exotropia surgery.

PURPOSE: To determine the effect of age on the reoperation rate in children undergoing exotropia surgery. METHODS: This was a population-based retrospective cohort study using claims data that included children ≤ 12 years who had undergone exotropia surgery as the first strabismus operation and had ≥ 3 years of continuous enrolment were selected from the Optum de-identified Clinformatics Data Mart Database (2003-2019). Patient age at the first exotropia surgery was grouped into three categories; 0-3, 4-6, and 7-12 years. We assessed the sex, race, age, surgical methods, continuous enrolment period after the first surgery, and the time between the first surgery and reoperation. Cox regression analysis was used to estimate the risk of reoperation at different ages. The hazard ratio of reoperation in children undergoing exotropia surgery according to the age at the first exotropia surgery. RESULTS: Among 2015 children, 312 (15.5%) underwent one or more reoperations. A reoperation was more often performed for recurrent exotropia (n = 231) than for consecutive esotropia (n = 81). The time between the first surgery and reoperation was shorter for reoperation for consecutive esotropia (376 days) than for recurrent exotropia (672 days) (p < 0.001). Younger children showed a higher reoperation hazard ratio than older children (p < 0.001). In reoperation for consecutive esotropia, the patients aged 0-3 years showed a high hazard ratio (2.82; 95% CI, 1.59-5.01). CONCLUSION: Children undergoing exotropia surgery at a younger age have a higher reoperation rate than those undergoing surgery at an older age.

A retrospective survey of strabismus surgery in a tertiary eye center in northern China, 2014-2019.

BACKGROUND: To evaluate the distribution pattern and changes of strabismus surgery in northern China. METHODS: The records of strabismus patients at Qingdao Eye Hospital from January 2014 to December 2019 were reviewed retrospectively. The characteristics analyzed included gender, regional distribution, constituent ratio of age and type of strabismus. Changes during the periods 2014-2016 and 2017-2019 were compared and analyzed. RESULTS: A total of 5746 strabismus patients were recruited. The number of strabismus patients was relatively stable each year from 2014 to 2016 but gradually increased each year from 2017 to 2019. Of these, 51.7% (2968/5746) were male, and 48.3% (2778/5746) were female. The majority (89.8%, 5159/5746) of the patients were from Shandong Province. The statistical results of the constituent ratio of age showed that 32.4% (1860/5746) were 7-12 years old (primary school level). Patients under 12 years of age (preschool and primary school level) accounted for 60.0% (3447/5746) of all the patients. In terms of the types of strabismus, exotropia accounted for 63.5% (3650/5746), followed by esotropia and vertical rotational strabismus at 13.2% (758/5746) and 9.7% (555/5746), respectively. Intermittent exotropia was the most common type among the exotropia patients, accounting for 71.3% (2604/3650). Among the patients with intermittent exotropia, 62.5% (1627/2604) were children aged 4-12 years, and the basic type of intermittent exotropia was the main type. Four percent (231/5746) of the patients, of which adult patients comprised the main population, required reoperation. CONCLUSIONS: Patients with strabismus at primary school level comprised the largest group of strabismus patients in north China. Exotropia was the most common type of strabismus, and intermittent exotropia was the most common type of exotropia. The rate of exotropia to esotropia was 5:1.

Indications and results of exotropia surgical management.

AIM: To study the clinical particularities and the surgical management of the different forms of exotropia, and to analyze the prognostic factors influencing the surgical result. METHODS: Medical records of 132 patients who underwent exotropia surgery from 1995 to 2015, were retrospectively reviewed. Ophthalmological examination and a complete sensorimotor assessment were performed for each patient. All surgeries were performed by the same surgeon. RESULTS: We had 57 cases of intermittent exotropia (IE), 22 cases of infantile exotropia (IfE), 43 cases of sensory exotropia (SE) and 10 cases of concecutive exotropia (CE). The average age of onset of exotropia was 6.8 years +/- 8 SD. Amblyopia was noted in 36.4% of cases  of  IfE.  The mean deviation angle was  36.5  DP in (IE),  39.6  DP in (IfE)  and  44.5  DP  in  (SE). A vertical syndrome was frequently found in (IfE) patients. Bilateral recession of  lateral  rectus  was  the  most  performed  surgery  type.  The overall success rate after a  single  surgery  was  72%.  A multivariate logistic regression analysis  showed  that good prognosis  factors  were  the absence  of  amblyopia, the intermittent form of the strabismus,  a low  preoperative deviation angle and the ocular alignment on day one postoperatively. CONCLUSIONS: IE is the most common divergent strabismus.  Surgery resulted in successful alignment in most of the cases.  Early management and rigorous analysis of  patients sensorimotor status are the best guarantors of long-term success.

Epidemiology of childhood manifest strabismus in the Republic of Moldova.

The purpose of this study was to determine the prevalence and the rate of newly detected pediatric manifest strabismus cases in the Republic of Moldova. A descriptive study was conducted in the Republic of Moldova. The data about the number of children that passed the prophylactic ophthalmological examination every year (children of 3 months- 17 years), the number of new strabismus cases found annually and the number of manifest strabismus cases under evidence were collected from the Health Family Centers in the Northern, Southern, and Central districts of the Republic of Moldova. The study period was performed in 2011- 2017. The prevalence rate of pediatric manifest strabismus in the study was 1.3%. The rate of newly diagnosed strabismus was 0.2%, with a higher ratio for esotropia versus exotropia (16.7/4.9 cases per 10000 children). The age of esotropia detection was mainly in the first 6 years of life (76.1%); beyond this age, exotropia predominates until the teenage years (75.6%). The study revealed a lower prevalence of pediatric manifest strabismus in comparison with the prevalence reported in other European countries. Esotropia was the most common type among patients with strabismus, this being detected mainly at first 6 years of life. The prevalence rate of exotropia was lower and the detection age was more frequent beyond the age of 6 years. The age at which most pediatric manifest strabismus cases were detected ranged between 3 and 6 years.

[Neglected childhood strabismus: Epidemiological, clinical and therapeutic aspects]. / Strabisme de l'enfance négligé : aspects épidémiologiques, cliniques et thérapeutiques.

INTRODUCTION: In an environment where strabismus is poorly understood and management centers rare, we studied the epidemiological, clinical and therapeutic aspects of neglected childhood strabismus. MATERIALS AND METHODS: This was a retrospective study carried out from March 1st, 2013 to September 30, 2018. Neglected childhood strabismus was defined as strabismus occurring in the first 5 years of life, for which the patient was over 7-years-old at the time of first consultation. The variables studied were age at first consultation, gender, age of onset, type of strabismus, etiology of strabismus, angle of deviation and rate of surgery. RESULTS: We found 113 cases of neglected childhood strabismus among the 430 cases of strabismus seen during the study period. There were more females (n=64) than males. The mean age was 17.7±10.5 years. There were 73 exotropias (64.6 %). The mean angle of deviation was 41.2±12.2PD. Strabismus was early in 70.8 % of cases. Innervational strabismus accounted for 86.7 % of cases. The most frequent refractive error was hyperopic astigmatism (55.3 %). Of the 45 patients who were seen again after full-time wear of their full cycloplegic correction, 2 were orthotropic. Surgery was performed in 60.5 % of cases. The average postoperative angle of deviation was 6.6±9.4PD. CONCLUSION: Management of neglected childhood strabismus provides good results and should therefore be encouraged in order to improve the quality of life of affected patients.

Comparison Between Parental Observations and Clinical Evaluation Findings in Korean Pediatric Patients With Intermittent Exotropia.

PURPOSE: To compare parental observations with the clinical evaluation findings in pediatric patients with intermittent exotropia and evaluate the clinical factors associated with the parental observations. METHODS: This prospective study included either one or both parents of pediatric patients with intermittent exotropia who visited the clinic between January and May 2019. The parental observations were assessed through a questionnaire that included questions on the age of onset, usually deviated eye, degree of awareness, and frequency of exotropia. These findings were compared with those of the clinical evaluations, including the amount of ocular deviation and level of control. RESULTS: A total of 100 parents (mean age: 39.7 years; 78 women) of 95 pediatric patients (mean age: 8.2 years; 47 girls) with intermittent exotropia participated in the study. The parental observation and clinical evaluation findings on the usually deviated eye showed good concordance (74%). The degree of parental awareness did not show any association with the amount of deviation. However, it showed a statistically significant increase associated with the worsening level of distance control (P = .04). The parental observations of the frequency of exotropia significantly increased with the worsening of the level of near (P = .037) and overall (P = .019) control. CONCLUSIONS: Parental observations are more likely to correlate with the level of control than with the amount of ocular deviation in pediatric patients with intermittent exotropia. [J Pediatr Ophthalmol Strabismus. 2020;57(3):199-203.].

Risk factors for spontaneous consecutive exotropia in children with refractive and nonrefractive accommodative esotropia.

PURPOSE: To investigate the risk factors for development of spontaneous consecutive exotropia (ScXT) among patients with refractive and nonrefractive accommodative esotropia (AET). STUDY DESIGN: Retrospective. METHODS: Patients who were diagnosed with AET were reviewed from January, 2000 to December, 2016. The patients who developed ScXT after well corrected hyperopia were defined as exodeviation group (n = 51), and the patients who did not show exodeviation and were well controlled with eyeglasses were defined as the control group (n = 117). The changes in cycloplegic refraction, mean angle deviation at initial visit, time till the first correction of esodeviation, presence of amblyopia and accompanying strabismus were compared between the two groups. RESULTS: The mean interval from the first visit to correction of esodeviation under 8 PD in the exodeviation group was shorter than of the control group (P = 0.008). Patients in the exodeviation group showed more dissociated vertical deviation (DVD) (P = 0.015) and faster reduction in hyperopia per year (more hyperopic eye: P = 0.006; less hyperopic eye: P = 0.034) than the patients in the control group. Exodeviation was found mean 42.31 ± 41.13 months after hyperopia correction. There were no differences in angle deviation at initial visit, and presence of amblyopia. CONCLUSION: ScXT can be found in AET with faster reduction in hyperopia per year, accompanied by DVD, or in eyes with esodeviation corrected in relatively shorter time. It can be noted even in patients with good alignment over a long-term, so long-term follow-up is recommended.

Outcomes of surgery in patients with sensory exotropia.

INTRODUCTION: Sensory exotropia is often due to profound amblyopia. Surgery essentially aims to improve aesthetic appearance and quality of life. Our goal was to discuss clinical features of sensory exotropia as well as surgical indications and outcomes. METHODS: Medical records of 43 patients who underwent sensory exotropia surgery were retrospectively reviewed. Each patient had an ophthalmological examination and a complete sensorimotor assessment. All surgeries were performed by the same surgeon. We studied the influence of certain prognostic factors on motility outcomes, such as age of onset of strabismus, gender, delay of surgical management, degree of amblyopia, angle of deviation, and amount of recession/resection. RESULTS: The mean follow-up was 2.3 years. All of our patients had severe amblyopia. An abnormal retinal correspondence with no fusion or stereopsis was noted in all subjects. The mean angle of deviation was 44.5 PD±12.4 SD preoperatively. The alignment success rate after a single procedure was 65.1%. Eight patients developed recurrent exotropia and were reoperated, with a final alignment success rate of 74.4%. CONCLUSIONS: Sensory exotropia is characterized by a large angle of deviation and an altered sensory status. The overall goal of surgery is to improve the patient's aesthetics and quality of life by treating the maximum angle of deviation. Surgical outcomes are often satisfactory for the patients, but certain complications may occur, such as diplopia, enopthalmos, and recurrences.

The prevalence of tropia, phoria and their types in a student population in Iran.

Purpose: The aim of this study is to determine the prevalence of tropia, phoria, and their types in Islamic Azad University students in Shahrekord, Iran.Methods: Of 826 students that were invited, 752 participated in this cross-sectional study (response rate = 91.04%). After applying exclusion criteria, statistical analyses were performed on the data of 726 individuals. All participants underwent optometric tests including measurement of visual acuity, objective and subjective refraction, as well as binocular vision and ocular health examinations. The unilateral and alternate cover tests were done to detect the tropia and phoria at 6 m and 40 cm, respectively.Results: The overall prevalence and 95% confidence interval (CI) of tropia, exotropia, and esotropia were 1.5% (0.8 to 2.7), 1.2% (0.6 to 2.4), and 0.3% (0.1 to 1.1), respectively. The prevalence of esotropia was significantly higher in older age groups (24 years old) (p = .040) . The prevalence of exotropia was significantly higher in females (0.039) and in myopic individuals (p = .001). The overall prevalence and 95% CI of phoria, exophoria, and esophoria were 12.9% (10.7 to 15.6), 11.7% (9.6 to 14.3), and 1.2% (0.6 to 2.3), respectively. There was a significant difference in the overall prevalence of exophoria according to the age (0.021). The prevalence of esophoria was significantly higher in females (p = .039). The prevalence of exophoria was significantly higher in myopic participants (p = .003). Exophoria and exotropia were the most common types of phoria and tropia, respectively.Conclusion: The prevalence of strabismus in university students was similar to the Iranian general population but lower than other countries. One in every 10 students had phoria, which was much lower than similar reports on Iranian populations; however, due to near-work activity, these students are prone to asthenopia, early visual fatigue, and decreased productivity. Therefore, it is suggested that university students also undergo screening programs to detect the cases of tropia and phoria.