伊朗亚兹德小儿斜视的流行与手术结果的调查研究

目的: 对伊朗亚兹德不同类型斜视的发病率及术后效果的调查。方法: 在此描述性研究中,对年龄低于 16 岁患斜视人群的医疗记录进行回顾性分析。收集术后效果及并发症的问卷数据,对其进行统计学分析。卡方检验用于定性分析,曼-惠特尼 U 检验用于定量分析。结果: 11a 间有 685 例儿童性斜视确诊。斜视类型如下:307 例 ( 44. 8% ) 外斜视,294 例 ( 42. 9% ) 内斜视,84 例( 12. 2%) 水平斜视合并垂直斜视。术后 280 例( 73. 9%)调整到正常水平( 水平偏差范围< 8Δ) 。结论: 研究中最常见的类型为外斜视。术后效果与已发表文献具有可比性。但仍需较长时间随访以评估手术效果。     

Global and regional estimates of prevalence of amblyopia: A systematic review and meta-analysis

Background: Amblyopia is one of the most important causes of vision impairment in the world, especially in children. Although its prevalence varies in different parts of the world, no study has evaluated its prevalence in different geographical regions comprehensively. The aim of the present study was to provide global and regional estimates of the prevalence of amblyopia in different age groups via a systematic search.

Methods: In this study, international databases, including Embase, Scopus, PubMed, Web of Science, and other relevant databases, were searched systematically to find articles on the prevalence of amblyopia in different age groups published in English. The prevalence and 95% CI were calculated using binomial distribution. The Cochran’s Q-test and I² statistic were applied to assess heterogeneity, a random-effects model was used to estimate the pooled prevalence, and a meta-regression method was utilized to investigate the factors affecting heterogeneity between studies.

Results: Of 1252 studies, 73 studies were included in the analysis (sample volume: 530,252). Most of these studies (n = 25) were conducted in the WHO-Western Pacific Regional Office. The pooled prevalence estimate of amblyopia was 1.75% (95% CI: 1.62–1.88), with the highest estimate in European Regional Office (3.67%, 95% CI: 2.89–4.45) and the lowest in African Regional Office (0.51%, 95% CI: 0.24–0.78). The most common cause of amblyopia was anisometropia (61.64%). The I² heterogeneity was 98% (p < 0.001). According to the results of univariate meta-regression, the variables of WHO region (b: 0.566, p < 0.001), sample size (b: ?0.284 × 10^?4, p: 0.025), and criteria for definition of amblyopia (b: ?0.292, p: 0.010) had a significant effect on heterogeneity between studies, while age group, publication date, and cause of amblyopia had no significant effect on heterogeneity.

Conclusion: The prevalence of amblyopia varies in different parts of the world, with the highest prevalence in European countries. Geographical location and criteria for definition of amblyopia are among factors contributing to the difference across the world. The results of this study can help stakeholders to design health programs, especially health interventions and amblyopia screening programs.     

Bupivacaine injection combined with recession of antagonist rectus muscle to treat sensory strabismus

Purpose: This study aims to evaluate the effect of bupivacaine injection at 1.5% combined with recession of the antagonist rectus muscle to treat sensory strabismus in adult patients.

Methods: Nine patients with a horizontal deviation, visual acuity of <20/60 in the worst-seeing eye, and no previous strabismus surgery were selected. Patients with vertical strabismus were excluded. Lateral rectus (LR) recession was performed in patients with exotropia and medial rectus (MR) recession in patients with esotropia according to Park’s Table, as modified by Wright. Bupivacaine 1.5 mL at 1.5% was injected in the antagonist of the recessed muscle. The patients were evaluated after 1, 7, 30, 60, 90, and 180 days of the procedure. Successful motor alignment was defined as within 10 prism diopters (PD) of orthophoria. Dose-response was considered as the total amount of correction, divided by recession performed in millimeters, associated with bupivacaine injection in the antagonist muscle.

Results: Of the patients, 44% (4/9) had a successful motor alignment. The mean correction for exotropia (n = 5) with a preoperative horizontal deviation of 50 ± 6.12 PD was 23 ± 14.4 PD with a dose-response of 2.6 PD/mm. For esotropia (n = 4), the mean correction of 21.25 ± 4.8 PD was achieved with a preoperative deviation of 28.7 ± 14.9 PD with a final dose-response of 5 PD/mm. All unsuccessful patients had a preoperative deviation of ≥45 PD.

Conclusion: Bupivacaine injection in the antagonist of a recessed extraocular muscle (EOM) appears to add an effect to the standard dose-response of a muscle recession. For patients with esotropia (<25 PD), a single MR recession combined with bupivacaine in the LR can produce a successful motor alignment. For patients with large horizontal strabismus (>45 PD), larger bupivacaine doses (volume and concentration) combined to larger recessions may be needed.     

知觉性内/外斜视与视力障碍发病年龄关系的研究

目的 研究知觉性内斜视或外斜视的发生与视力障碍发病年龄的关系。方法 回顾性分析169例知觉性斜视的临床资料,包括视力障碍的发病年龄、病因和知觉性斜视的类型等。结果 169例知觉性斜视中34例先天性视力障碍(20％),其中20例(59％)发生知觉性内斜视,14例(41％)发生知觉性外斜视;135例(80％)获得性视力障碍,其中21例(16％)发生知觉性内斜视;114例(84％)发生知觉性外斜视。两组间有显著性差异,x~2=27.67,P<0.01。86例视力障碍(51％)因白内障所致,其中无晶状体者64例(74％)。结论 先天性视力障碍(发病年龄≤6个月)主要发生知觉性内斜视,获得性视力障碍(发病年龄>6个月)主要发生知觉性外斜视。白内障是导致知觉性斜视最常见的原因。     

不同类型斜视患者术后双眼视觉重建的临床分析

目的:探讨先天性上斜肌麻痹性斜视、共同性外斜视和共同性内斜视患者手术前后双眼视功能的恢复情况及临床早期变化规律。方法:选择年龄介于3～20岁斜视矫正术后的斜视患者106例作为研究对象,按斜视类型分为三组,三组平均发病年龄分别为:7.7±1.2,8.5±1.4,8.1±1.3岁;病程分别为6.75±1.20,3.42±2.42和3.80±2.10a;斜视度分别为31.50△±5.50△,50.50△±12.56△和52.25△±13.80△。采用三棱镜加交替遮盖法检查手术前后远近斜视度,《颜少明立体视觉检查图》检查近立体视觉,同视机检查远立体视觉及融合功能,分析3种类型斜视术后眼融合功能恢复率及立体视功能恢复率情况,术后随访8wk。结果:三组术前平均发病年龄差异无统计学意义(P>0.05),先天性麻痹性斜视组与共同性斜视组病程、斜视度数差异有统计学意义(P<0.05),共同性外斜视组与共同性内斜视组病程及斜视度数差异无统计学意义(P>0.05)。术后2,4,6,8wk随访先天性上斜肌麻痹性斜视组融合功能恢复率分别为12.5%,37.5%,62.5%,68.8%,立体视功能恢复率分别为0,18.8%,50.0%,56.3%;共同性外斜视组融合功能恢复率分别为14.1%,40.8%,64.8%,69.0%,立体视功能恢复率分别为1.4%,31.0%,54.9%,59.2%;共同性内斜视组融合功能恢复率分别为26.3%,47.4%,73.7%,78.9%,立体视功能恢复率分别为5.3%,47.4%,63.2%,68.4%;术后2,4,6,8wk共同性外斜视组与共同性内斜视组术后眼正位率、立体视功能与融合功能恢复率差异均无统计学意义(P>0.05)。结论:先天性上斜肌麻痹性斜视患者斜视病程相对较长,术后近期立体视功能及融合功能恢复缓慢,且恢复率较低,于术后4wk开始明显提高,而共同性外斜视患者与共同性内斜视患者术后立体视功能及融合功能最早可于术后2wk恢复,且远期恢复率明显提高。     

伊朗亚兹德省斜视手术的效果和并发症(英文)

目的:斜视是一种注视方向不重合而双眼指向不同方向的视觉缺陷。其患病率为2%~5%。依斜视的不同表现,其治疗方法有:手术、眼镜、滴眼液、训练、注射液。斜视手术有不同的并发症。本研究旨在评估亚兹德省斜视手术的并发症和效果。方法:本研究对连续10a来的200例斜视手术的并发症和效果进行了回顾性分析。随访时间为6mo。数据被收集并进行了相应的统计分析。结果:本组病例中女98例,男102例,平均年龄15.31±11.7岁。外斜视和内斜视分别占43.5%和47%。斜视手术的效果和手术方式显著相关,但与斜视的发病年龄及病因无关。结论:斜视手术的效果是有效而持久的。随访可观察到长期效果和晚期并发症。基于本研究的结果和我们的个人经验,基于过矫和欠矫的Rosenbaum Santiago表格需要被修订。     

云南省青少年儿童斜视手术回顾性分析

目的:分析云南省青少年儿童斜视手术情况。方法:回顾性分析2017-01/2021-12于云南大学附属医院行斜视手术的青少年儿童患者3 068例的病历资料,分析纳入患者的性别和年龄构成、斜视类型分布、合并其它眼部疾病等情况。结果:纳入患者中男性占52.12%,女性占47.88%;学龄前(1～6岁)患者占32.89%,小学生(7～12岁)占45.89%,中学生(13～18岁)占21.22%;外斜视占63.17%,其中以间歇性外斜视最常见,内斜视占19.69%,其中以共同性内斜视最常见,特殊类型斜视占17.14%,其中以A-V综合征和分离性垂直斜视(DVD)最常见;合并屈光不正者占61.02%,合并弱视者占10.89%,少数患者还合并其他眼部疾病。结论:云南省青少年儿童斜视类型以间歇性外斜视最普遍,部分患者合并其他眼部疾病。     

Consecutive exotropia after surgical treatment of childhood esotropia: a 40‐year follow‐up study

Purpose: To determine the incidence of consecutive exotropia (XT) following successful surgical correction of childhood esotropia (ET) and identify factors associated with its development. Material and Methods: This is a retrospective study of 85 patients with ET, aged 2–24 , who underwent strabismus surgery by a single surgeon between 1958 and 1969 in Sweden, until they were successfully aligned to ET within 10 prism dioptre, after primary or reoperation(s). The charts of these patients were reviewed, and data regarding age at onset of strabismus, surgery performed and outcome were recorded. The patients were recalled for a complete orthoptic examination in 2001–2003. Results: The incidence of consecutive XT in this cohort was 21% (18/85). Patients who had undergone multiple surgeries had a higher risk of developing consecutive XT compared to those successfully aligned with one surgery (p = 0.00036). Restriction of adduction and convergence postoperatively was associated with a high risk of consecutive XT (p = 0.0437). The incidence of consecutive XT did not vary with the level of visual acuity in the operated eye (p = 0.6428). Age of onset, age at surgery and amount of surgery did not appear to influence the risk for developing consecutive XT (p > 0.05). Conclusion: This 40‐year postoperative follow‐up of patients with childhood ET who underwent strabismus surgery by a single surgeon in Sweden showed that multiple surgeries and presence of postoperative adduction deficit were the most important factors influencing the incidence of consecutive XT after surgery. Presence of uncorrected amblyopia did not alter the prognosis for long‐term development of consecutive XT.     

Bupivacaine Injection to Treat Exotropia and Esotropia

Purpose: To report the results of bupivacaine injection into the extraocular muscles to treat horizontal strabismus, both exotropia and esotropia.

Methods: Bupivacaine, 4.5?ml of a 0.50% solution, was injected into the medial rectus muscle in each of 14 exotropic patients and into the lateral rectus muscle in each of 6 esotropic patients with electromyographic control. The measures of alignment were made before the procedure and 1, 3, 6, and 12 months after injection.

Results: Of 20 patients, 15 had improved ocular alignment with the average change of 8.46, 8.2, 8.33 and 9 prism diopters (PD) at 1,3, 6 and 12 months, respectively. Two of 5 (40%) incomitant strabismus patients and 13 of 15 (86.66%) comitant strabismus patients had improvement in ocular alignment. Eleven of 14 exotropic patient and 4 of 6 esotropic patients had improvement in ocular alignment, averaging 9.73, 9.36, 9.54 and 6 PD in the exotropic group and 5, 5, 5, and 10.5 PD in the esotropic group. There was no serious complication from the injections.

Conclusions: Bupivacaine injection improved ocular alignment in some patients. Denervated extraocular muscle did not respond well to bupivacaine. Bupivacaine improved ocular alignment equally in esotropic and exotropic patients.     

知觉性斜视的临床特点及手术效果

目的：分析知觉性斜视的临床特点及手术效果。方法：分析2012－01／2013－06我科收治的178例知觉性斜视患者的临床资料,包括知觉性斜视的类型,斜视眼视力障碍的病因,斜视度数分布,观察术后眼位及复视现象。结果：知觉性斜视178例中知觉性外斜视123例（69．1％）,知觉性内斜视55例（30．9％）,知觉性斜视中109例为屈光参差性弱视,123例知觉性外斜视的平均斜视度为69．32△,其中78例合并垂直斜视,55例知觉性内斜视的平均斜视度为56．45△,其中26例合并垂直斜视。术毕6例患者出现复视,均于2wk内消失。手术设计按内斜欠矫10△左右,外斜过矫10△左右,术后眼位±10△内为正位,所有患者均行斜视眼手术,超过60△者按超常量一截一退手术设计,术后1a随访,178例斜视患者中138例术后眼位达到正位。结论：知觉性外斜视较知觉性内斜视更为常见,知觉性斜视最常见的病因为屈光参差性弱视,通常斜视度数较大,且常合并垂直斜视,知觉性斜视手术可以较好的改善斜视外观,提高患者生活质量。     

Acquired restrictive strabismus and high axial myopia: diagnosis and management

Objective: This paper documents the clinical, ultrasound, magnetic resonance imaging (MRI), and anatomic characteristics of 6 patients with esohypotropia and high axial myopia. The results of strabismus surgery performed on these patients are evaluated.Study Design: Retrospective cohort study.Participants: Six patients with esohypotropia and high axial myopia were selected from the practice of the second author (Michael Flanders).Methods: We extracted the history and data from the preoperative and postoperative ophthalmic and orthoptic examinations, recorded the surgical procedures, and tabulated the postoperative results. A- and B-scans, orbital MRI images, and photo documentation were obtained for all patients. Supramaximal recession and resection on the horizontal rectus muscles, using adjustable sutures, was performed in all patients. A surgical outcome was deemed successful if, in primary position, postoperative horizontal ocular alignment measured 15 prism diopters (PD) or less and (or) if diplopia was eliminated.Results: Echographic and MRI findings demonstrated an enlarged globe in all cases. Globe flattening on the orbital walls was found in 5 cases. Lateral rectus depression was visualized on MRI images in 4 cases. Surgical success was obtained in all patients. The average preoperative primary position esotropia measured 60 PD (25 to 90 PD) and the esodeviation after surgery was 7.0 PD (0 to 15 PD). Ductions were also improved.Conclusions: Different surgical approaches to realignment of eyes with high myopia and esohypotropia have been attempted. In this study, supramaximal amounts of recession and resection on the rectus muscles provided satisfactory results.     

Post-operative strabismus control and motor alignment for basic intermittent exotropia

AIM: To assess strabismus control and motor ocular alignment for basic exotropia surgery at 5y follow-up. METHODS: The medical records of 80 consecutive patients aged less than 17 years of age, who underwent surgery for basic exotropia by a single surgeon between years 2000 to 2009 and completed a minimum of 5y follow-up post-operatively were reviewed. Pre- and post-operative characteristics were documented at 1wk, 6mo, 1, 3 and 5y follow-up. Subjects at 5-year follow-up were assigned to the success group if they had a post-operative angle of deviation within 10 prism diopters of exotropia or within 5 prism diopters of esotropia for distance on prism cover test, and had moderate to good strabismus control. The remaining subjects were assigned to the failure group. RESULTS: Post-operative surgical success at one week was 75%, which decreased to 41% at 5y follow-up. The success group was noted to have more patching pre-operatively (P=0.003). The duration of patching a day (P=0.020) and total duration of patching pre-operatively (P=0.030) was higher in the success group. Surgical success at 1y (P=0.004) and 3y (P=0.002) were associated with higher surgical success at 5y follow-up. CONCLUSION: Post-operative motor alignment and strabismus control for basic exotropia surgery at 1y and beyond is associated with higher exotropia surgery success at 5-year follow-up. There is an association between pre-operative patching and 5-year surgical success of basic intermittent exotropia surgery.     

Strabismus and employment: the opinion of headhunters

Purpose: The aim of this study was to determine the influence of strabismus on an individual’s ability to find employment based on the opinion of Swiss headhunters. Methods: Forty Swiss headhunters retrieved from a Swiss online telephone directory were interviewed using a validated questionnaire in order to determine if strabismus would have an impact on a person's ability to find employment. Photographs of a strabismic man and woman as well as of other computer‐generated facial anomalies could be downloaded from the Internet during the interview. Results: 72.5% of headhunters judged that strabismic individuals would have more difficulties in finding a job than orthotropic persons. These difficulties were judged to be stronger in women than in men (P = 0.006), and in exotropic compared to esotropic persons (P = 0.01). Asked about seven facial anomalies, exotropia was found to have the third and esotropia the fourth (women) or fifth (men) most strongly negative impact on finding employment, after having strong acne and a visible missing tooth. Headhunters judged that persons with strabismus are significantly perceived as less attractive and less intelligent by potential employers. Conclusion: Visible strabismus negatively influences individuals’ ability to find a job and therefore has an impact on their economic status. Successful strabismus surgery realigns the visual axes, producing a normal facial appearance and therefore eliminating the negative impact of strabismus on employability.     

Global prevalence and clinical outcomes of tubercular uveitis: a systematic review and meta-analysis

Tubercular uveitis (TBU) is an inflammation/infection of the eye secondary to Mycobacterium tuberculosis infection. The difficulty in making the diagnosis has resulted in variable prevalence and clinical response rates. We aimed to determine the global prevalence of TBU in uveitis patients stratified by TB high-burden countries (HBCs) and non-HBCs and by geographic regions and the clinical response of TBU to antitubercular treatmentWe performed a systematic review and meta-analysis of TBU studies published in PubMed, Scopus and EMBASE, up to June 30, 2020. A random effects model was used for all meta-analyses. Of 5,018 articles identified, 70 prevalence studies (65,607 uveitis and 3,166 TBU cases) and 18 clinical outcome studies (1,570 TBU cases; 1,304 responded to anti-tubercular therapy [ATT]) were analyzed. The overall weighted prevalence of TBU was 4.0% (95% CI, 3–5); in TB HBCs it was 7.0% (95% CI, 5–11), non-HBCs 3.0% (95% CI, 2–4), and sub-Saharan Africa 11.0% (95% CI, 8–15). The overall weighted clinical response was 82.0% (95% CI, 75–89). Despite the difficulty in diagnosing TBU, the prevalence is expectantly higher in HBCs, and sub-Saharan Africa and the clinical outcome is poor. Standardization of diagnostic criteria and ATT is warranted in future cohort studies.     

Surgical treatment of myopic strabismus fixus: a graded approach

Background  Surgical treatment of myopic strabismus fixus is challenging. Options for its correction range from conventional combined recession-resection surgery to innovative surgical procedures aiming to correct the deviated muscle paths. In this report we review our experience and compare the results of various surgical options for treatment of strabismus fixus. Methods  We report the surgical outcomes of nine adults with acquired strabismus fixus due to myopia with a follow-up of 1 year. Patients were enrolled between May 2003 and April 2007 in this retrospective study. The surgical procedure was determined depending on the angle of deviation and extent of motility impairment. A new transposition technique was performed in one patient who had an extreme variant of strabismus fixus. Results  Combined recession-resection surgery was performed in four patients with resulting small-angle esotropia. In patients with both esotropia and hypotropia due to muscle alignment, we performed an additional upward displacement of both horizontal recti muscles combined with a myopexy of the lateral rectus muscle. The results were satisfying; in particular in one patient who had a transposition procedure a significant improvement was achieved. Conclusions  For treatment of myopic strabismus fixus, a graded approach seems advisable. Combined recession-resection surgery yields good results for smaller deviations with mildly impaired motility, additional fixation techniques need to be applied once the horizontal muscle paths are deviated, and in extreme cases, a transposition procedure is required.     

Myotonia congenita with strabismus in a large family with a mutation in the SCN4A gene

Background/AimsTo determine the genetic basis of myotonia congenita (MC) and strabismus in a large Caucasian family.MethodsSeven patients making up four generations of a family with MC and strabismus were recruited. All patients had at least one standard ophthalmic examination, including best-corrected visual acuity, refraction, and ocular motility measurements. CLCN1 and SCN4A genes were sequenced and analysed for mutations.ResultsFive out of the seven family members were diagnosed with MC by clinical history and electromyography. Ophthalmic history and exam revealed eyelid myotonia and strabismus. All patients with MC were diagnosed with strabismus between the ages of 3 and 6 and required surgical restoration of ocular alignment. Sequencing results revealed a c. 1333G>A; p. Val445Met mutation in the SCN4A gene.ConclusionThere are few reports describing eyelid myotonia and strabismus in patients diagnosed with MC. We found significant ocular involvement in a family with a mutation in SCN4A. Future studies may confirm that MC with significant ocular involvement can be used to direct genetic analysis.     

Epidemiology of Surgical Strabismus in Saudi Arabia

Purpose:?To describe the types and age differences of surgical strabismus.

Methods:?Records of 4,886 strabismus patients who underwent surgery at the King Khaled Eye Specialist Hospital in Riyadh, Saudi Arabia from 1982 to 1996 were analyzed. Demographic and clinical data were collected from all patients as a retrospective case series. The percentages and ratios of various types of strabismus were correlated with age and gender.

Results:?The average age of our patients was 13.2 years (range 4 months to 82 years). Esotropia was the most common type of strabismus (69.3%), while exotropia was less common (26.9%). Of patients undergoing esotropia correction, infantile esotropia and partially accommodative esotropia were equally common; non-accommodative was less common. Constant exotropia was almost three times more common than intermittent exotropia. The rate of sensory strabismus was high, 20.8% of all patients in the series, with a slight preponderance of sensory esotropia.

Conclusions:?The ratio of esotropia to exotropia in our study is comparable to previous studies done in predominantly European and Middle Eastern populations. Surgical esotropia decreased with age while surgical exotropia increased. Overall, our rates of sensory strabismus were much higher than previously reported, even if we compare only the younger patients.     

悬吊缝线后退术矫正内斜视的临床效果

目的 探讨悬吊缝线后退术矫正内斜视的疗效.方法 对内斜视39例(共同性内斜视37例、外伤后周定性内斜视2例)实施内直肌悬吊缝线后退术加外直肌缩短术.结果 术后远期正位35例.正位率89.74%;好转2例.总有效率94.87%.欠矫1例,欠矫率2.56%;过矫1例,过矫率2.56%.无并发症.结论 该术式是一种简便易行、安全有效的方法.     

Binocularity in comitant strabismus: Binocular visual fields studies

A critical review is made of the literature on binocular perimetry in strabismus. A broad range of results was obtained by various authors, because different testing techniques were used. The concept of sensory testing of strabismic patients in casual seeing condition should be introduced also into binocular perimetry. Therefore a series of experiments is presented in which patients with small-angle comitant strabismus were tested. It was shown that: a) in small-angle esotropia the areas of single vision previously thought to be due to suppression are, instead, areas of binocular vision sustained by anomalous retinal correspondence (ARC); b) this can be seen only when using fusable stimuli as test targets; c) no suppression scotomas were found in patients with smallangle strabismus in the whole visual field; d) appropriate control-marks for binocularity are necessary, i.e. monocularly presented items. They influence the results, as well e) the area of binocular single vision in strabismus (called pseudo-Panum's area) is wider than the Panum's area of normals. Moreover it is easier to disrupt binocular cooperation sustained by ARC causing diplopia than binocular cooperation in normals; f) ARC seems to be more deeply rooted in the center than in the periphery of the visual field; g) superimposable findings were obtained in small-angle constant exotropia; h) in largeangle exotropia wide suppression scotomas were found, which often override the midline. Hemianopic suppression scotomas in exotropia can be found only when dissociating testing techniques are used; i) the same group of patients with small-angle esotropia was examined with the author's technique and with the classical method proposed by Harms. The results were strongly dependent on the method used and the same patient responded differently to the two tests.It is concluded that in small-angle strabismus there is an anomalous type of binocular single vision, which can be tested with binocular visual field techniques. This binocularity can only be found when non-artificial testing conditions are used.The usefulness of this anomalous binocular vision in the every day seeing condition of the patient is discussed.     

Pedigree Analysis of Familial Primary Concomitant Horizontal Strabismus in Northern India

Purpose: Familial clustering of common forms of primary strabismus like esotropia (ET) and exotropia (XT) is observed in a proportion of the strabismus cohort. The genetic components of this remain unidentified. Linkage studies have demonstrated susceptibility locus for primary strabismus at the STBMS1 locus on 7p22.1 as well as other loci on 4q28.3 and 7q31.2. Recently next generation sequencing (NGS) technology has emerged as a powerful tool in discovery genomics and a large number of novel disease-causing variants are being reported. In this study, we recruited informative families for subsequent genetic analysis for disease-causing variant identification.

Methods: All consecutive families with two or more affected members with primary concomitant horizontal strabismus were prospectively recruited at the ophthalmic outpatients department (OPD) of Lady Hardinge Medical College, New Delhi, from August 2014 to February 2017. Detailed phenotypic evaluation and pedigree documentation was performed.

Results: Of the 39 recruited families of north Indian origin, 18 families each had affected family members demonstrating either ET or XT. 100% concordance of the phenotype in the affected family members was observed in these families. While vertical transmission was observed in 17/18 families with XT, 7 with ET had affected members across one generation, 2 demonstrated consanguineous pedigree, and 2 comprised identical twin families. In 3 families, a combination of ET and XT was noted. This comprised one family with the ET and XT patients being from 2 separate arms of the family related by marriage, one family where one sibling had XT and the other had ET, and another family where the maternal aunt of the affected proband with ET had XT.

Conclusions: Subjects with familial primary concomitant strabismus recruited in this study may provide a valuable resource to unravel the genetic determinants of this condition, which is a common disorder of early childhood with high ophthalmic morbidity.