Prevalence of strabismus in Pakistan: a systematic review and meta-analysis.

Purpose: Strabismus is an ocular condition characterized by misalignment of the visual axis. The global prevalence of strabismus is about 2-3%, which varies between different countries and ethnicities. The aim of this study was to conduct a meta-analysis of studies, which had previously reported the prevalence of strabismus in Pakistan, in order to obtain the overall prevalence of strabismus in the country. Methods: All community-based studies reporting the prevalence of strabismus from Pakistan were searched using international databases and local ophthalmology journals. Information about sample size, number of individuals with strabismus, and location and duration of the study was recorded. Statistical analysis including heterogeneity testing, pooled prevalence calculation and regression analysis were done using the R software. Results: Heterogeneity tests, Pheterogeneity < .01, suggested high heterogeneity between the different studies. The pooled prevalence of strabismus was 0.7% [95% confidence interval (CI): 0.39%-1.23%] according to the random effects model, with a decreasing trend in prevalence from 1995 to 2020. Esotropia was more frequent than exotropia in both population-based and clinic-based studies. Conclusion: The prevalence of strabismus in Pakistan is comparatively lower than the worldwide prevalence, and it appears to be decreasing over the last three decades, consistent with global trends.

Prevalence of visual abnormalities detected through paediatric vision screening in Queensland, Australia.

BACKGROUND: Vision screening programs can provide epidemiological information regarding visual impairment in children. This study aims to report the characteristics of visual abnormalities diagnosed through the Primary School Nurse Health Readiness Program (PSNHRP) in Queensland, Australia. METHODS: A retrospective review of vision screening records from the PSNHRP between January 2017 and December 2020 was undertaken. Children aged between 4 and 7 who underwent vision screening were included for review. Children with a visual acuity of worse than 6/9-1 using the Parr 4 m letter-matching chart or those who failed the SPOT Vision Screener were referred to an optometrist or ophthalmologist for review. RESULTS: 164 890 children underwent vision screening. 12148 children failed visual screening (7.4%) and were referred for an eye assessment. 6011 (69.4%) of the 8659 children who attended ophthalmic review had a confirmed visual abnormality. Of 164 890 screened children, 1187 (0.72%) were confirmed to have anisometropia, 3843 (2.33%) had refractive error, 194 (0.12%) had strabismus, 755 (0.46%) had anisometropic amblyopia, 136 (0.08%) had strabismic amblyopia, and 1356 (0.82%) had an unspecific abnormality. There was no statistically significant difference in the age at screening between any visual abnormality (p = 0.94). Anisometropia, refractive error, and strabismus were significantly more common in females than males (p = 0.03, p < 0.01, and p = 0.03 respectively), whereas anisometropic amblyopia was more common in males (p < 0.01). CONCLUSIONS: We report the prevalence of visual abnormalities detected through the PSNHRP vision screening program. Identification of medical or socioeconomic risk factors that are likely to be associated with visual abnormalities can help to optimise vision screening programs.

A retinal detachment based strabismus detection through FEDCNN.

Ocular strabismus, a common condition in the present generation is an absolute risk factor for amblyopia and blinding premorbid visual loss. Despite the availability of new optometry tools with eye-tracking data, the issues persist in attaining accuracy and reliability in diagnosing strabismus. These two concerns are specifically accommodated in this study by the proposed novel approach that involves CNNs with eye-tracking datasets from subjects. The presented work aims to improve the accuracy of diagnostics in ophthalmology utilizing the integration of the further proposed algorithms into an automatic strabismus detection system. For this purpose, the proposed FedCNN model combines the CNN with eXtreme Gradient Boosting (XGBoost) and uses the Gaze deviation (GaDe) images to capture dynamic eye movements. This method tries to make the feature extraction as accurate as possible in its best working state to enhance the diagnosis precision. The model proves to be accurate, reaching 95.2%, which is even more prominent because of the more or less detailed connection layer of the CNN, which is used for the selection of features designated for such tasks of strabismus recognition. The presented method has the potential of shifting the approach to diagnosing diseases of the eyes in more or less half of the patients.

Strabismic Adults' Experiences of Psychosocial Influence of Strabismus-A Qualitative Study.

Introduction: Strabismus influences health-related quality of life. Individuals may have functional and psychosocial consequences of strabismus that impact their well-being. As strabismus is prevalent in all age groups, patients are seen in varied specialties in healthcare organizations. Therefore, healthcare professionals need to be aware of the psychosocial consequences when caring for strabismic individuals. Objective: To describe strabismic adults' experiences of the psychosocial influence of strabismus. Methods: Twelve strabismic adults participated in face-to-face or online semistructured individual interviews to share their experiences of the psychosocial influence of strabismus. The participants were selected purposefully. The data were analyzed using inductive content analysis. Results: The participating adults described challenges with social environments, which showed stress in social situations and pressure in interactions. Strabismic adults had experienced staring from others, avoided social situations, and were uncomfortable with photography. They hid their strabismus, avoided eye contact, and struggled with intimate relationships. They also expressed struggles with mental well-being, which were emotional and psychological burdens. The adults described feeling negative emotions, worry, and irritation due to their condition. Struggles with self-confidence, difficulties with acceptance, negative thoughts about their appearance, experiences of bullying, and dealing with being different were described. Conclusion: Strabismic adults experience psychosocial consequences of strabismus, influencing their psychosocial health-related quality of life. Further studies should focus on how healthcare professionals could support strabismic individuals' psychosocial well-being.

Risk Factors for Acute Acquired Comitant Esotropia in Children and Young Adults: A Systematic Review.

Background: Acute acquired comitant esotropia (AACE) is a rare subtype of esotropia that occurs after infancy. The exact pathogenesis of AACE remains unknown with aetiologies ranging from benign conditions to serious underlying neurological diseases being reported. Given the elusive characteristic of AACE, diagnostic and management guidelines remain unclear. This systematic review aims to contribute to this field by summarising the risk factors for AACE reported thus far. Methods: A systematic review was conducted with papers found in CINAHL, MEDLINE, Cochrane library, PubMed databases and other sources. Eligible studies investigating the risk factors for, and clinical features of, AACE in children and young adults were critically appraised before relevant data were extracted and discussed via a narrative summary. Results: Twelve studies were included in the final review, of which six and eight papers reported on benign and non-benign risk factors for AACE respectively. Identified benign risk factors varied among studies, while non-benign risk factors were associated with intracranial pathologies, multiple sclerosis and head trauma. Conclusion: Given the low generalisability of study findings, no definitive conclusions can be drawn on the significance of each risk factor on AACE development. Further prospective research with more objective measurements of 'near work', larger sample sizes and control groups is required to better ascertain any cause-effect relationship, refine the diagnostic criteria for each AACE subtype and advise on appropriate management guidelines for AACE.

FEVR combined with macular heterotopia in children presenting as pseudo-exotropia: a case report and literature review.

Familial exudative retinopathy (FEVR) is a hereditary disease involving abnormal retinal vascular development in which macular heterotopia (MH) caused by mechanical-like pulling of the vitreous may lead to pseudo-strabismus. We describe the case of a 12-year-old male patient from China who presented to our hospital with a request for surgical correction of exotropia. Examination revealed that the strabismic appearance was due to MH, and dilated pupil examination of the peripheral fundus revealed that the blood vessels of the left eye and the macula were displaced toward the temporal retina by pulling, and further FFA examination was performed to diagnose FEVR. With good binocular vision and stereoscopic distance vision, corrective surgery for strabismus in this patient would have resulted in a hard-to-resolve diplopia. Therefore, it is important to identify FEVR combined with MH in clinical practice to avoid wrong diagnostic and treatment options.

Understanding parental hurdles in accessing strabismus treatment.

Purpose: To explore the parental factors that impede early intervention for strabismus and thus identify strategies for improving access to specialized care. Methods: This hospital-based cross-sectional study included 110 parents of children under 19 years with strabismus receiving treatment at the squint clinic of a tertiary health care center in north India. A pre-validated survey questionnaire was administered to the participants, that had a section about the socio-demographics of the participants, another section addressed the parental knowledge about strabismus about diagnosis, and the need for an eye examination. It also sought information about referral source, the felt need for squint examination, and reasons for not seeking treatment. Results: A total of 110 parents/guardians of strabismus patients (59 exotropes and 51 esotropes) were interviewed using a survey questionnaire. Parents themselves identified 80% of cases, and a substantial link (P â€‹< â€‹0.0001) was found between the education status of parents and the age of identification of strabismus. Fear of surgical outcomes (41.79%) was a significant barrier to timely surgery with a higher percentage of parents expressing fear of surgical outcomes (P â€‹= â€‹0.025). The cost of surgery (34.33%) and the non-availability of facilities (23.88%) also delayed the intervention. Conclusions: It is essential to educate parents about the importance of strabismus therapy at an appropriate time, stressing its reconstructive rather than merely cosmetic nature, as there are notable gaps in their knowledge. Also, we need to do away with the fear of surgical outcomes of surgical interventions for strabismus.

Prevalence of Amblyogenic Risk Factors Among School Children in India Using the Spot Vision Screener.

INTRODUCTION: Amblyopia is a common cause of preventable visual impairment in children, affecting 1% to 6% globally. This study assesses amblyopia prevalence and risk factors among school children in rural Telangana, India, using the Spot Vision Screener (Welch Allyn, Inc., Skaneateles Falls, New York, USA), a portable, noninvasive device recommended for automated vision screening. METHODS: A cross-sectional study was conducted on 714 schoolchildren aged 5-10 years. Screening was performed using the Spot Vision Screener, evaluating refractive errors, ocular alignment, and other amblyopia risk factors. Children identified with potential amblyogenic factors were referred for comprehensive ophthalmological evaluation to confirm diagnosis. RESULTS: Out of 714 children screened, 84 were referred by the Spot Vision Screener for further evaluation. Subsequent examination by ophthalmologists confirmed amblyopia in 65 children, resulting in a prevalence of 9.10%. Myopic refractive error was the most prevalent (69.23%), followed by astigmatism (21.53%) and hypermetropia (9.23%) among amblyopia cases. CONCLUSION: The Spot Vision Screener proved to be a reliable tool for identifying amblyopia risk factors in school children, facilitating early detection and referral for appropriate management. This study underscores the importance of implementing effective vision screening programs in rural settings to mitigate preventable childhood blindness.

Characteristic differences between full-term and premature infants with intermittent exotropia.

Strabismus is prevalent among preterm infants of low gestational age and birth weight in Southeast Asian countries, with intermittent exotropia (IXT) being the most common type in South Korea. In this retrospective, cross-sectional study, we investigated the differences between full-term and premature infants with IXT. IXT patients with available childbirth history were divided into two groups: preterm vs. full-term and low birth weight (LBW) vs. normal birth weight (NBW). Parameters related to exotropia including parental heredity, surgical history, and treatment options were investigated. In univariate regression for gestational age, a result of ≥ 100 s in the Titmus test was 1.352 times more frequent in preterm than in full-term infants. When birth weight was considered instead, a result of ≥ 100 s in the Titmus test was 1.412 times more frequent in the LBW compared to the NBW group. In multivariate regression for birth weight, the frequency of a result of ≥ 100 s in the Titmus test for the LBW group was 2.032 times higher than that for the NBW group. It is particularly important to examine stereopsis in preterm and LBW patients affected by IXT to ensure timely surgical planning and avoid potential recurrence after surgery.

A rare case of inferior rectus dermoid cyst causing proptosis and optic neuropathy.

Purpose: To report a rare case of orbital dermoid cyst, involving the inferior rectus muscle, in a 26-year-old female presenting with proptosis and blurred vision in her right eye. Observations: The unique features of this case are discussed, including the location and contents of the cyst, the surgical approach, and the postoperative outcome. Conclusion and importance: The importance of considering dermoid cysts in the differential diagnosis of an orbital mass involving extraocular muscles and the need for a thorough evaluation to diagnose and manage these rare lesions.

Corneal changes after large (9mm) lateral rectus muscle recession measured with Pentacam®.

Introduction: The aim of this study was to evaluate alterations in corneal astigmatism, axial anterior corneal curvature, anterior chamber depth, and central corneal thickness (CCT) two months after the unilateral recession of lateral rectus muscle in children. Methods: This prospective study included 37 children with intermittent exotropia who would undergo unilateral lateral rectus muscle recession. All measurements were performed using Pentacam®. Comparisons were made between the operated and fellow unoperated eyes, pre- and post-operatively. The assessment was made for changes in the radius of axial curvature on major meridians at 3 and 3.5 mm from the optical corneal center in the mid-peripheral zone. Astigmatism changes of the anterior and posterior corneal surface were calculated using vector analysis software (astigMATIC®). The interaction between age or CCT and postoperative changes in anterior and posterior surface corneal astigmatism were examined with ANOVA model. Results: In the intervention group, changes in anterior and posterior corneal surface astigmatism were statistically significant, with a mean increase of 0.56Dx90 and 0.08Dx87, respectively. In the mid-peripheral corneal zone, an increase was observed in the radius of anterior corneal axial curvature, more evident temporal 3 and 3.5 mm from the corneal center on the horizontal meridian, with corresponding decrease superiorly and inferiorly at 3 and 3.5 mm from the corneal center on the vertical meridian. Discussion: The changes in total astigmatism of the operated eyes are mainly attributed to the anterior corneal surface. These changes are associated with flattening in the 180 meridian of the cornea, leading to a shift to "with-the-rule" astigmatism.

Gestational age, maternal smoking, neurological lesion and retinopathy predict strabismus at age 5.5 in preterm children.

AIM: Prematurity is a risk factor for strabismus, but the roles of intermediate factors like retinopathy of prematurity (ROP) and neurological lesions are less understood. We aimed to identify neonatal risk factors for strabismus at age 5.5 in preterm children. METHODS: Data were extracted from the étude épidémiologique sur les petits âges gestationnels 2 cohort, a French prospective population-based study of preterm children born in 2011 with gestational age of 34 weeks or less. Strabismus was recorded during a medical interview at 5.5 years. Using a directed acyclic graph, intermediate and confounding factors were identified. Total and direct effects of gestational age on strabismus risk were analysed using generalised estimating equation. RESULTS: Among 2419 children assessed, 274 (52.6% male) presented strabismus at 5.5 years. The direct effect of gestational age remained significant after adjustment (p < 0.001). In the complete imputed model: maternal smoking during pregnancy (odds ratio, OR 1.8; 95% confident interval, 95% CI 1.3-2.6), neonatal severe cerebral lesions (OR 2.9, 95% CI 1.8-4.6) and severe ROP (OR 4.2, 95% CI 1.9-9.0) were independent risk factors. CONCLUSION: Special attention is needed regarding strabismus screening at age 5.5 in preterm children, even without severe cerebral lesions and ROP. Smoking cessation during pregnancy should be encouraged.

Risks of Hyperopia, Myopia, Astigmatism, and Strabismus in Children With Autism Spectrum Disorder: A Nationwide, Population-Based Cohort Study.

OBJECTIVE: In this population-based cohort study, we compared the risks of incident hyperopia, myopia, astigmatism, and strabismus between children with autism spectrum disorder (ASD) and children without ASD. METHODS: This study included children who were born in Taiwan at any time between 2004 and 2017. Data were collected from the Taiwan Maternal and Child Health Database. We included 20,688 children with ASD and 2,062,120 matched controls to estimate the risks of incident hyperopia, myopia, astigmatism, and strabismus. Cox proportional hazards regression models were constructed for risk assessment. The models were adjusted for sex, calendar year of birth, and gestational age at birth. Statistical significance was determined by calculating adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs). RESULTS: Children with ASD had higher risks of incident hyperopia (aHR: 1.78; 95% CI: 1.70-1.86), myopia (aHR: 1.27; 95% CI: 1.24-1.30), astigmatism (aHR: 1.51; 95% CI: 1.46-1.56), and strabismus (aHR: 2.18; 95% CI: 2.05-2.32) than did those without it. CONCLUSION: Clinicians should screen children with ASD for potential ophthalmic conditions. Further studies are required to elucidate the mechanisms underlying the associations between ASD and ophthalmic diseases. The roles of types and severities of ASD symptoms in detecting ophthalmic disease also requires further study.

Surgical Outcomes and Factors Related to Their Success of Infantile Esotropia in a Tertiary Hospital: A Retrospective Study.

Purpose: This study aims to evaluate the outcomes of surgical intervention for infantile esotropia at a tertiary care hospital. Patients and Methods: Medical records of patients with esotropia who underwent surgical correction at our tertiary hospital between January 2013 and June 2023 were retrospectively analyzed. Patient demographics, preoperative and postoperative ocular alignment, surgical techniques employed, complications or reoperations, and factors related to successful surgery were analyzed. Results: The study included 77 participants with an average age of 9.54 ± 10.87 years at the time of surgery. Postoperatively, 71.4% (55/77) patients achieved successful alignment, which was defined as an ocular deviation of ≤10 prism diopters (PD), at the final follow-up. The average follow-up period was 12 months, during which no complications were noted. Reoperation was required in 15.6% (12/77) patients. Multivariate logistic regression revealed that having a smaller preoperative deviation of <50 PD positively influenced the success of strabismus surgery (adjusted odds ratio, 7.13; 95% CI, 2.04-24.86). Conclusion: The surgical correction of infantile esotropia in a tertiary care setting yielded favorable alignment outcomes in most cases, with no complications and a low reoperation rate. A preoperative angle of <50 PD emerged as a prognostic factor for successful surgical outcomes in this population. Further studies with longer follow-up periods are recommended to evaluate the long-term stability of these outcomes and identify additional influencing factors.

This study reviewed the outcomes of surgery for infantile esotropia, a condition where one or both eyes turn inward. We analyzed medical records of patients who underwent surgical correction for esotropia at a tertiary care hospital between January 2013 and June 2023. We collected information about patient demographics, eye alignment before and after surgery, the types of surgeries performed, any complications, and factors related to successful outcomes. The study included 77 patients, who had an average age of ~9.5 years at the time of surgery. After surgery, 71.4% (55 out of 77) of patients achieved successful eye alignment, defined as an eye deviation of 10 prism diopters or less. Patients returned for follow-up after an average of 12 months, and no complications were reported. However, 15.6% (12 out of 77) of patients required reoperation. Our analysis showed that patients with a smaller initial eye deviation (less than 50 prism diopters) were likely to have successful outcomes. In conclusion, surgery for infantile esotropia in our hospital resulted in good alignment in most cases, with no complications and a low rate of repeat surgeries. Having a smaller initial eye deviation strongly predicted the success of the surgery. Further research with longer follow-up periods is needed to determine the long-term outcomes and identify other factors that may influence outcomes.

Clinical outcomes of inferior oblique myectomy in age categorized patients with unilateral superior oblique palsy.

Background: Unilateral superior oblique palsy (SOP) is the most common isolated cranial nerve palsy. This report looks at the results and safety of inferior oblique (IO) myectomy for SOP. Methods: A retrospective chart review of patients with fusional ability who underwent IO myectomy for unilateral SOP over a 15-year period, at one of our university-associated health care centers. Primary outcomes were: distance hypertropia and excyclotropia in primary position, inferior oblique overaction (IOOA) and the correlation between the age at surgery and the residual distance hypertropia. Results: A total of 73 patients with unilateral SOP who underwent IO myectomy were included in the analysis. Mean pre-operative values were: distance hypertropia: 15.41 ± 6.8 Prism Diopters (range 4-30 PD), IOOA: +2.2 ± 0.7 (range 0-3.5) and excyclotropia: +5.34 ± 3.6° (range 0-12°). Mean post-operative values were: distance hypertropia: 3.7 ± 3.4PD [0-14PD], IOOA: -0.1 ± 0.8 [(-2)-2] and excyclotropia: +1.1 ± 2.3°[(-5)-10]. The younger age group (0-20 years old) had a trend toward smaller preoperative distance hypertropia (P = 0.051), and a significantly smaller distance hypertropia post-operatively (p = 0.007). There was no case of ocular complication. Conclusions: On average, IO myectomy results in a 11.7PD reduction of the distance hypertropia, and 4° reduction of excyclotropia, with an effective reduction of IOOA. While these results are comparable to other surgical methods reported in the literature, they underline an efficacy without the risks of complications such as anti-elevation syndrome and possible scleral perforation. The younger age group had a trend toward smaller preoperative deviation, and better outcomes compared to the older age group.

Amblyopia and physical activity in adolescents.

Introduction: Physical activity in adolescence plays an important role in reducing the lifetime risk of chronic disease. Recent studies have shown that individuals with amblyopia may have difficulties with coordinating balance and may be at greater risk of developing fine motor impairments. The purpose of this study was to determine if there is an association between the presence of amblyopia and physical activity (PA) in adolescents. Methods: Adolescent patients aged 12-18 years with a history of childhood amblyopia were age- and gender-matched to control patients with no other ocular pathology aside from refractive error. Each participant's best corrected visual acuity and refractive error were recorded in addition to their height and weight to calculate body mass index (BMI). A 32-question electronic survey was used to calculate self-reported physical activity level (PAL) score and type of PA over the previous seven days. The Ainsworth Compendium of Physical Activities was taken as a reference to calculate Metabolic Equivalent of Task (MET) minutes for the most frequently performed activity. Results: A total of 26 adolescents with amblyopia (10 strabismic, 16 anisometropic) and 26 healthy controls were recruited. The MET-minute values were 2404.3 ± 2313.9 in the control group and 905.6 ± 1196.0 in the amblyopia group (p = .008). The PAL scores were similar between amblyopia and control groups (1.15 ± 0.70 versus 1.24 ± 0.60, p = .63); however, BMI was significantly higher in amblyopia participants (25.2 ± 6.3 versus 21.1 ± 5.4, p = .003). When compared with controls, amblyopes perceived physical activity to be of significantly lower importance in their lives compared to controls (p = .009). Discussion: Amblyopic adolescents may represent a population with increased vulnerability to significantly lower energy expenditure and higher BMI. Future studies with a larger number of participants and further investigation into the impact of refractive error on physical activity are warranted.

Surgery for Esotropia in a Case of Nanophthalmos.

Nanophthalmos, characterized by an abnormally small ocular globe, presents significant challenges in the management of strabismus due to its unique anatomical constraints. This detailed case report highlights the intricacies and outcomes of strabismus surgery in a patient with nanophthalmos, providing valuable insights into the surgical considerations and adaptations required for this rare condition. The subject of this case, a young girl diagnosed with esotropia and high hyperopia, underwent unilateral medial rectus muscle recession in an attempt to correct her esotropia. Despite the careful surgical approach and postoperative management, a two-year follow-up revealed a limited response to the intervention, with improvements in visual acuity but continued presence of esotropia and lack of stereopsis development. This case sheds light on several key considerations in the surgical treatment of strabismus in nanophthalmos patients, including the potential for reduced surgical effectiveness due to the small globe size, the importance of accurate preoperative assessment, and the challenges in predicting surgical outcomes. Additionally, it discusses the implications of these findings for future surgical planning, the potential need for revision surgeries, and the broader research context, emphasizing the necessity for a deeper understanding of the biomechanical and anatomical particularities of nanophthalmos in the context of strabismus surgery. The report concludes with recommendations for improving surgical strategies and patient outcomes, advocating for more comprehensive studies and a tailored approach to treating strabismus in individuals with nanophthalmos.

Bilateral medial rectus recession with or without posterior fixation in large-angle infantile esotropia: a randomized controlled trial.

PURPOSE: To compare the results of bilateral medial rectus recession (BMRc) versus bilateral medial rectus recession with Faden operation (BMRF) in the treatment of large-angle infantile esotropia. STUDY DESIGN: A double blinded, parallel, randomized controlled trial. METHODS: Patients with large-angle infantile esotropia (≥ 60 prism diopters, [PD]) aged between 3 and 15 years old were included and assigned to either the BMRc or BMRF group. Mean difference and mean reduction of angle deviation between the two groups were compared at 1 week, 1, 3, and 6 months by using generalized estimating equations analysis. Surgical success rates, defined as an esodeviation ≤ 10 PD at near fixation, were evaluated at 6 months postoperatively. Complications from the surgical procedures were observed. RESULTS: Of 40 enrolled patients, the mean (SD) age of the patients in the BMRc group was 3.4 (1.9), and in the BMRF group, 5.2 (3.8) years old. The overall mean differences of angle reduction between both groups were not significant (-6 PD, 95%CI -14 to 2, P = .12). The surgical success rate at 6 months in the BMRF group (72%) was not different compared to BMRc group (84%, P = .45). Overall consecutive exotropia was 5%, not different between groups (P > .99). There was no difference of complications between the two groups (P = .51). CONCLUSION: BMRF and BMRc approaches show no difference in treatment of large-angle infantile esotropia. Nevertheless, a long-term assessment for consecutive exotropia should be considered for both surgical procedures.