Clinical features of Sudanese patients presenting with binocular vision anomalies: A hospital-based study.

Binocular vision anomalies are major causes of asthenopia symptoms, particularly among the younger population. This study aimed to report the clinical characteristics of Sudanese patients with binocular disorders who attended the orthoptic clinic at Al-Neelain Eye Hospital. In this retrospective hospital-based study, we analyzed data from 304 patients with binocular vision anomalies who visited the orthoptic clinic between October 2020 and June 2021. We collected information on demographics, symptoms, and eye tests such as visual acuity (VA), refractive error (RE), angle of deviation, and the assessment of fusional vergence. Our findings indicated that exophoria was the most common binocular vision anomaly, affecting 79.8% of males and 71.6% of females (p=0.731). Children between 6 and 17 years old showed the highest prevalence of exophoria (75.9%) (p=0.0001). Among patients with exophoria, 100% reported itching associated with tearing during fixation, while 89.5% experienced difficulty in fixation. Refractive error varied by the type of binocular vision disorders (p=0.0001), with higher hyperopia observed in cases of unilateral esotropia and alternate esotropia (+3.571±1.238 D and +3.023±1.553 D, respectively). Positive fusional vergence (PFV) differed by types of binocular vision disorders (p=0.0001) with high PFV in esophoria (18.063±6.848∆) compared to low PFV in exophoria (12.80±5.313∆). The most common types of exophoria were convergence weakness exophoria (45.39%), followed by convergence insufficiency (20.39%). The study concluded that exophoria was the most common binocular vision anomaly among Sudanese patients, with convergence weakness and convergence insufficiency being the predominant anomalies. Headache was commonly prevalent among patients with binocular vision problems. Higher hyperopia was found in esodeviation, while low PFV was associated with exodeviation.

Frequencies and patterns of symptoms in Chinese adults with accommodative and binocular dysfunctions.

PURPOSE: Recent studies have found that children with convergence insufficiency experience higher frequencies of performance-related symptoms (e.g., losing concentration), but data on performance-related symptoms among adults with accommodative dysfunctions (ADs) and/or binocular dysfunctions (BDs) are lacking, which might cause misdiagnosis, diagnostic confusion, or exacerbation of attention deficits. We aimed to describe frequencies and symptom patterns in adults with ADs and/or BDs who were treated at optometric clinics and explore any correlations between visual symptoms and clinical findings. METHODS: This cross-sectional study divided 235 participants (age: 23.7 ± 2.9 years) into three groups: ADs, BDs, and normal binocular vision (NBV) groups. Convergence Insufficiency Symptom Survey (CISS), refractive examinations, and binocular tests were administered to all participants. After 1-to-1 propensity score matching, outcomes were assessed using Mann‒Whitney U test and Pearson's correlation analysis among three groups. RESULTS: In this sample, the number (frequency) of individuals with ADs and/or BDs was 117 (49.8%). ADs and BDs groups experienced significantly more performance-related symptoms (feeling sleepy, losing concentration, trouble remembering, reading slowly, losing place, and having to re-read; all P < 0.05) than the NBV group. Significant correlations were observed between performance-related symptoms and clinical findings, including accommodative amplitude (r = - 0.294), accommodative facility (r = - 0.452), near phoria (r = - 0.261), near point of convergence (r = 0.482), and positive fusional vergence (r = - 0.331) (all P < 0.001). CONCLUSION: ADs and/or BDs are commonly present in adults treated at optometric clinics, and adults diagnosed with ADs and/or BDs exhibit more performance-related symptoms than participants with NBV.

Convergence insufficiency: Review of clinical diagnostic signs

Convergence insufficiency (CI) is a common binocular vision (BV) disorder characterized by difficulty in maintaining motor fusion at near, which affects approximately 7.5 percent of the population. Diagnostic criteria for the disorder are inconsistent, ranging from one to many clinical signs. Methodology for clinical tests is inconsistent in measurement technique, visual targets, required repetitions, and normative values.This manuscript demonstrates the inconsistencies amongst published studies, and highlights the importance of consistent clinical diagnostic signs, measurement techniques, visual targets, and cut-off criteria. For each clinical sign, the recommended methodology for the procedure is described. Several studies do not take age into account when diagnosing CI in their cohorts. As such, the review emphasizes changes in diagnostic signs with age.This manuscript highlights the need for consistent and clear procedures and diagnostic criteria amongst clinicians and provides the basis for future studies in terms of diagnostic testing required for CI of varying age groups. (AU)

Preoperative binocular vision characteristics in the age-related cataract population.

BACKGROUND: This study is the first part of the "Binocular Vision Anomalies after Cataract Surgery" study that aimed to investigate the impact of cataract surgery on binocular vision status in adults with age-related cataract. This study aimed to investigate the preoperative binocular vision status of participants with age-related cataract. METHODS: Patients who elected to undergo bilateral cataract surgery (≥50 years of age) were recruited. Clinical measures of binocular vision including stereopsis, ocular alignment, fusional vergence, vergence facility, convergence amplitude and a symptom survey related to binocular vision anomalies were administered. A detailed classification protocol was established to identify the presence of binocular vision anomalies. The frequency of specific binocular vision anomalies and normative data of binocular vision measures were reported. RESULTS: A total of 73 subjects were evaluated. No strabismus was detected in the cohort. Non-strabismic binocular vision anomalies were detected in 24 subjects (32.9%), of whom 18 (24.7%) had convergence insufficiency, 3 (4.1%) had basic exophoria, 2 (2.7%) had convergence excess, and 1 (1.4%) had fusional vergence dysfunction. Decreased vergence facility and convergence amplitude were more common compared to the pre-presbyopes (P < 0.01). CONCLUSION: Binocular vision problems, especially convergence insufficiency, are common in the adults with age-related cataract. The study results demonstrate that the lack of normative binocular vision data for the presbyopic population is a significant gap in the literature and suggest the need for a study of normative data for this population. TRIAL REGISTRATION: The study was registered at ClinicalTrials.gov (NCT03592615, USA).

Ocular features of patients with Parkinson's disease examined at a Neuro-Optometry Clinic in a tertiary eye care center.

PURPOSE: To report the ocular features of patients with PD who presented with visual complaints to a tertiary eye care center. METHODS: This was a retrospective study carried out between January 2015 and March 2020 at the Neuro-Optometry clinic of a tertiary eye care center in Southern India. All PD patients with ocular complaints examined by the neuro- ophthalmologists were referred to Neuro-Optometry Clinic for detailed evaluation. Patients with other neurodegenerative disorders, brain injury, and other causes of vision loss or extraocular motility disorders were excluded. RESULTS: A total of 43 patients (7 females, 36 males) between 50 and 86 years of age (mean: 70 ± 8.9 years) with a mean duration of PD of 4.5 ± 4.5 years were studied. Decreased vision associated with reading difficulty (40%) was common in PD patients. In terms of gaze restriction, vertical gaze involvement (35%) was more than horizontal involvement (7%). Convergence insufficiency (CI) was the most common binocular vision dysfunction (30%), followed by CI with oculomotor dysfunction (14%) and vertical gaze palsy (18%). Ground prisms were recommended for 26 patients (61%) and home vision therapy for 5 patients (12%) as corrective measures. CONCLUSION: Binocular vision dysfunction is highly prevalent among PD patients. This could potentially contribute to the reading difficulties and double vision encountered by these patients. Assessment of binocular vision and oculomotor parameters thus becomes important to understand and manage the reading difficulties in patients with PD.

The visual consequences of virtual school: acute eye symptoms in healthy children.

PURPOSE: To investigate acute eye symptoms in healthy children after a typical day of virtual school during the COVID-19 pandemic. METHODS: The study population included 110 healthy children 10-17 years of age who were enrolled in full-time or hybrid virtual school. Children with a history of central nervous system or ocular pathology, recent concussions, reported poor vision, convergence insufficiency, history of orthoptic therapy, strabismus, amblyopia, or learning disorders were excluded. Background information was collected, including demographics, family and personal ocular history, and virtual school specifications. Eligible children completed a modified convergence insufficiency symptom survey (CISS) and an asthenopia survey before and after a virtual school session. CISS and asthenopia survey symptoms were scored, and the differences in symptomatology before and after school were calculated. RESULTS: The average sum of the CISS scores increased from 5.17 before school to 9.82 after (P < 0.001), with 61% of children recording an increase in convergence insufficiency symptoms and 17% experiencing severe convergence insufficiency symptoms after school. Average asthenopia symptom scores increased from 1.58 to 2.74 (P < 0.001), with 53% of children recording an increase in asthenopia symptoms. Significant increases were seen in 12 of 15 CISS questions and in 4 of 5 asthenopia questions. CONCLUSIONS: In this study cohort, otherwise healthy children experienced acute ocular symptoms following virtual school.

Non-strabismic Binocular Vision Dysfunction among the Medical Students of a Teaching Hospital: A Descriptive Cross-sectional Study.

Introduction: Non-strabismic binocular vision dysfunctions are visual disorders that affect the person's binocular vision and visual outcome while performing near tasks and are very common among medical students. This study aimed to find out the prevalence of non-strabismic binocular vision dysfunction among the medical students of a teaching hospital. Methods: A descriptive cross-sectional study was conducted among medical students of a teaching hospital from 25 April 2022 to 25 May 2022. Ethical approval was obtained from the Institutional Review Committee of the same institute (Reference number: 139/17). A detailed ocular evaluation including history, visual acuity, refraction, and detailed orthoptic evaluation was done. Convenience sampling was done. Point estimate and 95% Confidence Interval were calculated. Results: Out of 284 students, 79 (27.81%) (22.60-33.02, 95% Confidence Interval) had non-strabismic binocular vision dysfunctions. Convergence insufficiency was the commonest one seen in 38 (48.10%), followed by divergence excess seen in 8 (10.12%) and convergence excess seen in 8 (10.12%) students. Conclusions: The prevalence of non-strabismic binocular vision dysfunction among medical students was lower than in other studies conducted in similar settings. Keywords: binocular vision; convergence excess; convergence insufficiency; prevalence.

Convergence insufficiency: Review of clinical diagnostic signs.

Convergence insufficiency (CI) is a common binocular vision (BV) disorder characterized by difficulty in maintaining motor fusion at near, which affects approximately 7.5 percent of the population. Diagnostic criteria for the disorder are inconsistent, ranging from one to many clinical signs. Methodology for clinical tests is inconsistent in measurement technique, visual targets, required repetitions, and normative values. This manuscript demonstrates the inconsistencies amongst published studies, and highlights the importance of consistent clinical diagnostic signs, measurement techniques, visual targets, and cut-off criteria. For each clinical sign, the recommended methodology for the procedure is described. Several studies do not take age into account when diagnosing CI in their cohorts. As such, the review emphasizes changes in diagnostic signs with age. This manuscript highlights the need for consistent and clear procedures and diagnostic criteria amongst clinicians and provides the basis for future studies in terms of diagnostic testing required for CI of varying age groups.

Application of the Convergence Insufficiency Symptom Survey in Oculomotor Dysfunction and Accommodative Insufficiency.

SIGNIFICANCE: This study confirmed the application of the Convergence Insufficiency Symptom Survey (CISS) in distinguishing children with oculomotor dysfunction (OMD) from those with normal binocular vision (NBV) but not in distinguishing children with accommodative insufficiency (AI). PURPOSE: The purpose of this study was to determine the application of the CISS for quantifying symptoms in children aged 9 to 18 years with AI or OMD. METHODS: All participants (aged 9 to 18 years) underwent comprehensive binocular vision tests including visual acuity, cover test, near point of convergence, fusional vergence, accommodative amplitude, and the Developmental Eye Movement test to ascertain the presence of any vision conditions. According to the examination outcomes, participants were divided into four groups: NBV group, AI group, OMD group, and a group with both AI and OMD (AI-OMD). The CISS was individually administered to each participant. An ANOVA and a receiver operating characteristic curve were performed to evaluate the ability of the CISS to quantify symptoms in AI and OMD. RESULTS: A total of 82 participants were qualified for this study, with 18 in the NBV group, 21 in AI, 16 in OMD, and 27 in AI-OMD group. The mean CISS score was significantly different among the four groups (F = 4.19, P = .008). Post hoc tests showed significantly higher CISS scores in the OMD group than the NBV (P = .01) and the AI (P = .03) groups, but no differences were detected among other groups. Receiver operating characteristics curve showed a significant effect of the CISS score on predicting an OMD (area under curve = 0.78, P = .006). Using a CISS score of ≥15, good discrimination of OMD was obtained. CONCLUSIONS: Children with OMD (Developmental Eye Movement type II or IV) had higher CISS scores than ones with NBV. Using the CISS, children with AI did not report worse symptoms than children with NBV.

The rate of superior oblique surgery in children and adolescents with Brown syndrome according to claims data.

PURPOSE: To determine the rate of superior oblique surgery and how often it is combined with surgery on other extraocular muscles or associated with subsequent strabismus surgeries in children and adolescents with Brown syndrome. METHODS: This was a population-based retrospective cohort study using the Optum deidentified Clinformatics Data Mart Database (2004-2018) for patients ≤18 years of age diagnosed with Brown syndrome who underwent superior oblique surgery as their first strabismus surgery and had at least 6 months of continuous enrollment. We assessed sex, age, and the number of included patients by year and by age. Combined and subsequent strabismus surgeries were also investigated. RESULTS: Of 1,007 patients diagnosed with Brown syndrome, 115 (11.4%) underwent superior oblique surgery. The rate of superior oblique surgery was relatively constant between 2004 to 2018. The superior oblique surgery rate was highest in children ≤2 years of age with a decreasing rate as age increased. In 45 of 115 patients (39.1%), other extraocular muscles were operated on in addition to the superior oblique muscle. Of 88 patients who underwent superior oblique surgery without concurrent vertical muscle surgery as the first operation, 11 patients (12.5%) subsequently underwent an additional vertical muscle surgery because of newly developed or worsening vertical misalignment. CONCLUSIONS: In this study cohort, superior oblique surgery was performed on 11.4% of children and adolescents with Brown syndrome. The number of patients with Brown syndrome and the rate of superior oblique surgery decreased as age increased to age 10 years.

Convergence Insufficiency in the Geriatric Population.

SIGNIFICANCE: The present study is the first population-based study to examine the prevalence of convergence insufficiency and its associations specifically in the geriatric population. Knowledge of the population-based determination of prevalence of this disorder in the elderly is necessary to support proper clinical diagnosis and management. PURPOSE: This study aimed to determine the prevalence of convergence insufficiency and its associated factors in a geriatric population. METHODS: In this study, all residents older than 60 years in Tehran city were selected through random stratified cluster sampling. All participants underwent a complete ocular examination including the measurement of uncorrected and best-corrected visual acuity, objective and subjective refraction, binocular vision assessments including unilateral and alternating cover tests, measurement of the near point of convergence, the positive fusional vergence, and finally ocular health examination. RESULTS: In this population-based sample of 1793 participants, the overall prevalences of two-sign and three-sign convergence insufficiency were 29.6% (95% confidence interval, 27.2 to 32.0%) and 21.5% (95% confidence interval, 19.5 to 23.6%), respectively. There were no statistically significant differences in the prevalence of both two-sign (P = .19) and three-sign (P = .41) convergence insufficiency between men and women. The highest and lowest prevalences of two-sign and three-sign convergence insufficiency were in the age groups 70 to 74 and 75 to 79 years, respectively. The prevalence showed no significant trend with age (P = .26 for two-sign convergence insufficiency, P = .33 for three-sign convergence insufficiency). In the multiple logistic regression model, none of the variables, including age, sex, and refractive errors, showed a significant relationship with convergence insufficiency (all, P > .05). CONCLUSIONS: The results of the present study showed a high prevalence of convergence insufficiency in the geriatric population. Clinicians should give special attention to this binocular vision disorder in this age group.

Clinical Outcome and Technical Nuances After Resection of Orbital Cavernous Venous Malformations-A Single-Center Experience.

BACKGROUND: Cavernous venous malformations (CVMs) represent the most common benign intraorbital lesions. Enlarging or symptomatic CVMs (progressive proptosis or visual disturbances) are treated by surgical resection. For this, a variety of different surgical approaches have been described. The aim of this study was to present a contemporary series of orbital CVMs treated via open microsurgical approaches. METHODS: In this study, patients who underwent resection of orbital CVMs between 2002 and 2019 were included. Presenting symptoms were noted and neuro-ophthalmologic examinations performed pre- and postoperatively. For surgical resection, the location of the orbital CVM and its relation to the orbital anatomy led to decision-making for appropriate approaches. A comparison between anatomical location and surgical outcome was performed. RESULTS: Overall, 35 patients with orbital CVMs were included. Most common presenting symptoms were progressive proptosis (43%) and visual disturbances (34%). Most common location was the lateral quadrant (37%) followed by the superior quadrant (20%). A subfrontal craniotomy was performed in 40% of cases followed by a supraorbital craniotomy including the orbital rim in 34% of cases. For surgical excision, a cryo-probe was used in 30 patients, and complete resection was feasible in all cases. Location of a CVM within the superior quadrant was associated with improved postoperative recovery of visual acuity. No differences for clinical outcomes were observed depending on the surgical approach. CONCLUSIONS: Resection of orbital CVMs is indicated in patients with visual disturbances or progressive proptosis. In these, microsurgical approaches can be used with minimal morbidity for complete removal of these well-circumscribed lesions.

Frequency of oculomotor disorders in adolescents 11 to 17 years of age with concussion, 4 to 12 weeks post injury.

The purpose of the study was to determine the frequency of vision diagnoses after concussion in adolescents and evaluate the sensitivity and specificity of physician-administered screening for detecting convergence and accommodative disorders post-concussion. We enrolled participants 11 to 17 years old, assessed 4 to 12 weeks following a diagnosed concussion. During the initial concussion examination, a sports medicine physician measured the near point of convergence (NPC), monocular accommodative amplitude (AA), and symptoms using the Convergence Insufficiency Symptom Survey (CISS). A comprehensive oculomotor evaluation was performed by an optometrist. One hundred and thirteen adolescents were enrolled, with a mean age of 15.2 years. Seventy-nine of the 113 (70%) participants had at least one oculomotor diagnosis after concussion, with the most common problems being vergence disorders (60%) and accommodative disorders (57%). The most common vergence disorder was convergence insufficiency (35%). Among accommodative disorders, the most common problem was accommodative insufficiency (35%). In all, 47% of the participants had more than one oculomotor diagnosis following concussion. The sensitivity of physician screening using measures of NPC, AA, and CISS for detecting convergence and accommodative insufficiency was 63%, 43%, 48%, respectively. The results of this study provide additional evidence that vision problems are common in adolescents with persistent concussion symptoms in the sub-acute phase 4 to 12 weeks post-concussion, and current physician screening methods using the NPC, AA, or the CISS underperform. Thus, it is prudent that adolescents with post-concussion symptoms lasting more than 4 weeks post injury receive a comprehensive oculomotor examination.

Abnormal eye movements in spinocerebellar ataxia type 3.

BACKGROUND: Abnormal eye movements are common in spinocerebellar ataxias Type 3 (SCA3). We conducted the research to explore the frequency of abnormal eye movements in Chinese patients with SCA3, to compare the demographic and clinical characteristics between SCA3 patients with and without each type of abnormal eye movement, and to explore the correlation between abnormal eye movements and the severity of ataxia. METHODS: Seventy-four patients with SCA3 were enrolled in this cross-sectional study. Six types of abnormal eye movements including impaired smooth pursuit, increased square-wave jerks (SWJ), gaze-evoked nystagmus (GEN), slowing of saccades, saccadic hypo/hypermetria and supranuclear gaze palsy were evaluated by experienced neurologists. The severity of ataxia was evaluated by Scale for the Assessment and Rating of Ataxia (SARA). RESULTS: The prevalence of impaired smooth pursuit, increased SWJ, GEN, slowing of saccades, saccadic hypo/hypermetria and supranuclear gaze palsy in Chinese SCA3 patients was 28.4, 13.5, 78.4, 41.9, 23.0, and 5.4%, respectively. SCA3 patients with GEN had higher scores of International Cooperative Ataxia Rating Scale (ICARS-IV) and total ICARS, and longer length of CAG repeat than patients without GEN. SCA3 patients with slowing of saccades had a longer disease duration, higher scores of ICARS-I, ICARS-II, total ICARS and SARA than patients without slowing of saccades. SCA3 patients with saccadic hypo/hypermetria had higher scores of ICARS-III, ICARS-IV, and SARA than patients without saccadic hypo/hypermetria. The demographic and clinical characteristics did not differ significantly between SCA3 patients with and without impaired smooth pursuit, increased SWJ, or supranuclear gaze palsy. Multivariate linear regression showed that the number of abnormal eye movements (0-6), disease duration, Hamilton Depression Rating Scale-24 (HDRS-24) score, and CAG repeat length were positively correlated with SARA score, whereas Montreal Cognitive Assessment (MoCA) score was negatively correlated with SARA score in SCA3. CONCLUSIONS: An increased number of abnormal eye movement types correlated with the severity of ataxia in SCA3.

The Influence of COVID-19 Isolation on Physical Activity Habits and Its Relationship with Convergence Insufficiency.

The purpose of this work is to evaluate the effects of confinement due to COVID-19 isolation on visual function, considering insufficient convergence as one of the possible effects of living the whole day in a reduced space. We pass a Convergence Insufficiency Symptom Survey (CISS) among 235 people to detect their habits before and after 25 confinement days. The data collection protocol consisted on a Google forms questionnaire included two parts: the first with current data (isolation period) and a second with pre-isolation period data. Differences between the pre-isolation and isolation period were calculated using the related paired T-tests. When statistically significant differences were found, the effect size was estimated using the Cohen's d index (d). The reduction in physical activity levels during confinement were related to the increase in total number of minutes of screen consumption from 433.49 min to 623.97 min per day (d = 0.67; 44.01%). The CISS scores were increased by more than 43% during confinement. The increase in convergence insufficiency was 100% after the studied isolation period of 25 days. The 92.19% increase in television use during 25 days of confinement is not responsible for the increase in convergence insufficiency. However, due to the increase in the use of PCs in this period, there is a notable increase in convergence insufficiency. Therefore, we can conclude that not all increases in tasks with electronic devices are responsible for the increase in convergence insufficiency.

Vestibular and oculomotor abnormalities among HIV-infected and HIV-uninfected men and women: A pilot study.

OBJECTIVE: To determine if middle-aged and aging men and women with HIV disease (HIV+) should be screened for vestibular and oculomotor dysfunction. METHODS: Age- and sociodemographically matched HIV+ and HIV- men and women were tested on vestibular evoked myogenic potential (VEMP), bi-thermic caloric testing, Dix-Hallpike maneuvers and saccades. RESULTS: HIV+ men had more caloric weakness than HIV- men. HIV+ subjects had more saccade abnormalities than HIV- subjects. A saccade abnormality was positively associated with being HIV+. Among the HIV+ sample, abnormalities were associated with increasing age, being male, ever taking monotherapy, and having an undetectable viral load. Only being male and having an undetectable viral load were statistically significant. Unilateral caloric weakness had a decreased prevalence with age per 10 years, and being HIV+ showed an increased prevalence. In HIV+ subjects only, these abnormalities decreased with age and being male but increased with undetectable viral load and ever taking antiretroviral monotherapy. No statistically significant differences were found. CONCLUSION: Women are at greater risk of vestibular and oculomotor abnormalities than men. HIV+ adults are at greater risk than HIV- adults. Physicians who care for HIV+ men and women should monitor the symptoms of vestibular and oculomotor impairment.

Changing vergence function in persons with Parkinson's disease and convergence insufficiency.

Individuals with Parkinson's disease and convergence insufficiency were assigned vergence training. After two months, average positive fusional vergence increased and average near point of convergence decreased. Vergence can be improved with training in persons with Parkinson's disease who also have convergence insufficiency.

Clinical, ocular motor, and imaging profile of Niemann-Pick type C heterozygosity.

OBJECTIVE: To characterize subclinical abnormalities in asymptomatic heterozygote NPC1 mutation carriers as markers of neurodegeneration. METHODS: Motor function, cognition, mood, sleep, and smell function were assessed in 20 first-degree heterozygous relatives of patients with Niemann-Pick disease type C (NPC) (13 male, age 52.7 ± 9.9 years). Video-oculography and abdominal ultrasound with volumetry were performed to assess oculomotor function and size of liver and spleen. NPC biomarkers in blood were analyzed. 18F-fluorodesoxyglucose PET was performed (n = 16) to detect patterns of brain hypometabolism. RESULTS: NPC heterozygotes recapitulated characteristic features of symptomatic NPC disease and demonstrated the oculomotor abnormalities typical of NPC. Hepatosplenomegaly (71%) and increased cholestantriol (33%) and plasma chitotriosidase (17%) levels were present. The patients also showed signs seen in other neurodegenerative diseases, including hyposmia (20%) or pathologic screening for REM sleep behavior disorder (24%). Cognitive function was frequently impaired, especially affecting visuoconstructive function, verbal fluency, and executive function. PET imaging revealed significantly decreased glucose metabolic rates in 50% of participants, affecting cerebellar, anterior cingulate, parieto-occipital, and temporal regions, including 1 with bilateral abnormalities. CONCLUSION: NPC heterozygosity, which has a carrier frequency of 1:200 in the general population, is associated with abnormal brain metabolism and functional consequences. Clinically silent heterozygous gene variations in NPC1 may be a risk factor for late-onset neurodegeneration, similar to the concept of heterozygous GBA mutations underlying Parkinson disease.

Receiver operating characteristic curve analysis of clinical signs for screening of convergence insufficiency in young adults.

Convergence insufficiency (CI) is a dysfunction of binocular vision that is associated with various signs and symptoms in near work. However, CI screening is performed less frequently in adults than in children. We aimed to evaluate the ability of screening tests to discriminate CI from other binocular vision anomalies and normal binocular vision in young adults. One hundred eighty-four university students (age, 18-28 years) who underwent an eye examination due to ocular discomfort were included. Near point of convergence (NPC), phoria, accommodative amplitude, fusional vergence, the ratio of accommodative convergence to accommodation, relative accommodation, binocular accommodative facility, vergence facility, and the values corresponding to Sheard's and Percival's criteria were evaluated. Receiver operating characteristic (ROC) curve analysis for each test was also performed. The prevalence of CI ranged from 10.3% to 21.2%, depending on the signs and the presence of CI associated with accommodative disorders. Assessments based on NPC, Sheard's criterion, and Percival's criterion showed high discriminative ability, with the ability being higher between the CI and normal binocular vision groups than between the CI and non-CI groups. Sheard's criterion showed the highest diagnostic performance in discriminating CI with three signs from the non-CI group. The cut-off values were 7.2 cm for NPC, -0.23 to 1.00 for Sheard's criterion, and -4.00 to -2.33 for Percival's criterion. Our results suggest that the use of Sheard's criterion with NPC shows high performance for screening of CI.

Prevalence of ocular morbidities among school children in Raipur district, India.

Purpose: To estimate the prevalence of various ocular morbidities in school children (5-15 years) utilizing a comprehensive mobile eye unit in Central India. Methods: A prospective, cross-sectional, school-based observational study was carried out in Raipur, Chhattisgarh, India between December 2017 and September 2018. A total of 1557 eligible school-going children in the age group 5-15 years were evaluated. Random sampling was done to allocate schools (n = 29) and children from various urban and rural (836 vs 721) schools. The primary objective was to estimate the prevalence of ocular morbidities in school-going children in Raipur district, India. The secondary objective was to analyze whether geographical location (rural vs urban), age group, and gender led to any differences in ocular morbidity patterns. Results: The mean age of the study population was 10.3 ± 2.4 years. There were 691 (44.4%) boys and 866 (55.6%) girls. Ocular morbidity was present in a total of 331 (21.2%) children. Vitamin A deficiency was the most common cause of ocular morbidity, noted in 156 (10%) children, followed by refractive error (81, 5.2%). Myopia was significantly higher in urban school children (4.3%) compared to rural children (1.9%) (P = 0.002). The older age group had a higher prevalence (7.6%) of refractive error, especially myopia, compared to the younger age group (2.2%) (P < 0.001). Conclusion: Vitamin A deficiency prevalence was much higher indicating missed opportunities for vitamin A supplementation at a younger age. Refractive error was more prevalent in the urban population as well in the older age group (11-15 years), indicating a need for frequent eye screening.