Genome-Wide Association Study with Three Control Cohorts of Japanese Patients with Esotropia and Exotropia of Comitant Strabismus and Idiopathic Superior Oblique Muscle Palsy.

Esotropia and exotropia in the entity of comitant strabismus are multifactorial diseases with both genetic and environmental backgrounds. Idiopathic superior oblique muscle palsy, as the predominant entity of non-comitant (paralytic) strabismus, also has a genetic background, as evidenced by varying degrees of muscle hypoplasia. A genome-wide association study (GWAS) was conducted of 711 Japanese patients with esotropia (n= 253), exotropia (n = 356), and idiopathic superior oblique muscle palsy (n = 102). The genotypes of single nucleotide polymorphisms (SNPs) were determined by Infinium Asian Screening Array. Three control cohorts from the Japanese population were used: two cohorts from BioBank Japan (BBJ) and the Nagahama Cohort. BBJ (180K) was genotyped by a different array, Illumina Infinium OmniExpressExome or HumanOmniExpress, while BBJ (ASA) and the Nagahama Cohort were genotyped by the same Asian array. After quality control of SNPs and individuals, common SNPs between the case cohort and the control cohort were chosen in the condition of genotyping by different arrays, while all SNPs genotyped by the same array were used for SNP imputation. The SNPs imputed with R-square values ≥ 0.3 were used to compare the case cohort of each entity or the combined entity with the control cohort. In comparison with BBJ (180K), the esotropia group and the exotropia group showed CDCA7 and HLA-F, respectively, as candidate genes at a significant level of p < 5 × 10-8, while the idiopathic superior oblique muscle palsy group showed DAB1 as a candidate gene which is involved in neuronal migration. DAB1 was also detected as a candidate in comparison with BBJ (ASA) and the Nagahama Cohort at a weak level of significance of p < 1 × 10-6. In comparison with BBJ (180K), RARB (retinoic acid receptor-ß) was detected as a candidate at a significant level of p < 5 × 10-8 in the combined group of esotropia, exotropia, and idiopathic superior oblique muscle palsy. In conclusion, a series of GWASs with three different control cohorts would be an effective method with which to search for candidate genes for multifactorial diseases such as strabismus.

Advances in the diagnosis and treatment of acute acquired comitant esotropia.

Acute acquired comitant esotropia (AACE) is mainly characterized by sudden onset, accompanied by diplopia, without extraocular muscles paralysis or ocular motility disorders. In recent years, the incidence of AACE has been increasing, researchers have found that this phenomenon may be related to the widespread use of electronic devices and the increase in the number of people working from home during the COVID-19 pandemic. However, its neural mechanisms have not been fully elucidated. This article primarily reviews the latest developments in the diagnosis and treatment of AACE from the perspectives of etiology and treatment methods, aiming to provide direction for future in-depth exploration of the pathogenesis and treatment approaches of this disease.

The effects of refractive status on the outcomes of strabismus surgery in patients with esotropia.

BACKGROUND: The success of the strabismus surgery can hinge on several factors. One of these factors is refractive condition like hyperopia or myopia. Our study seeks to evaluate the surgical outcomes in patients with esotropia and myopia. METHODS: This case-control study encompassed all surgical cases of esotropia at Torfe and Negah Hospital between 2016 and 2021, which satisfied our specified inclusion criteria. The initial variables from electronic medical records were collected, including demographic, clinical, and surgery-related factors. At the final follow-up appointment, the level of eye deviation, both at distance and near, was recorded. We considered the operation a "success" for patients with a post-surgery distance eye deviation of 10(Pd) or less. Patients with greater deviation were classified as surgery failure. Statistical analyses were executed using SPSS software (version 16.0), and a P-value less than 0.05 was considered significant. RESULTS: Of the 194 patients evaluated, 112 were incorporated into the study. Surgical failure was observed in 14.29% of myopic patients, 29.79% of hyperopic patients, and 31.82% of emmetropic patients. The myopia group displayed a 0.19 odd ratio for surgical failure compared to the combined hyperopia and emmetropia groups, not statistically significant (OR: 0.19, CI 95%: 0.03-1.02). Additionally, patients diagnosed with Lateral Rectus Under-action were found to be 6.85 times more likely to experience surgery failure(OR: 6.85, CI 95%: 1.52-30.94). An elevated risk of surgical failure was also identified in patients who underwent Inferior Oblique Weakening procedure, indicated by a 3.77-fold increase in the odds ratio for failure(OR: 3.77, CI 95%: 1.08-13.17). CONCLUSION: In our study, despite numerical disparities, there was no statistical difference among the success rates of all esotropia patients with different refractive errors. The patients with LRUA or IOOA showed lower success rates. Myopic patients had higher post-op overcorrection with lower reoperation rates compared to hyperopic or emmetropic patients.

Pilot Study Assessing the Effect of Exam Room Length on the Measurement of Strabismus.

PURPOSE: Our study aims to investigate the effect of decreasing distance from the patient to the fixation target on the measurement of strabismus with a known distance-near disparity. METHODS: Strabismus measurements were taken by one pediatric ophthalmologist at our standard distance of 18 feet and compared to those taken at 16, 14, 12, and 10 feet from the fixation target. A clinically meaningful difference was defined as >2.5 prism diopters (PD), since a difference of that magnitude may alter surgical planning. RESULTS: Thirty-nine subjects, including 22 exotropes and 17 esotropes, were included in this study. Mean prism diopter difference (PDD) in the exotrope group at lengths of 16, 14, 12, and 10 feet compared to 18 feet were 1.3 (SD 1.9, range 0-6), 1.3 (SD 2.2, range 0-8), 1.7 (SD 3.2, range 0-14), and 2.8 (SD 4.4, range 0-14), respectively. Among esotropes, the mean PDD at the same distances were 1.1 (SD 1.9, range 0-7), 2.1 (SD 2.6, range 0-7), 3.9 (SD 4.9, range 0-19), and 4.3 (SD 5.1, range 0-19). The percentages of exotropes with a PDD of >2.5 at 16, 14, 12, and 10 feet compared to 18 feet were 13.6% (n = 3), 13.6% (n = 3), 18.2% (n = 4), and 27.3% (n = 6), respectively. In the esotrope group, 11.8% (n = 2), 35.3% (n = 6), 47.1% (n = 8), and 47.1% (n = 8) had a PDD of >2.5 at the same distances, respectively. CONCLUSION: This pilot study is the first to investigate the change in measured angle of strabismus at various non-mirrored distances from the patient to the fixation target. Our methodology defines a framework that could be used in a higher-powered study to further our understanding of the effect of room length on strabismus evaluation.

Effect of 4-week preoperative prism adaptation in preventing postoperative residual esotropia.

BACKGROUND: Preoperative prism adaptation (PPA) simulates postoperative status and possibly can predict postoperative undercorrection before surgery in esotropia. The present study aimed to assess the effect of 4-week PPA in preventing postoperative residual esotropia. METHODS: Seventy-five (75) esotropes who had undergone surgery at a single strabismus center were retrospectively enrolled. They included 25 basic, 31 acute comitant, 10 partially accommodative, and 9 recurrent esotropia patients. The preoperative deviation angle, which had been determined using the alternating prism and cover test, was fully corrected with press-on prisms 4 weeks before surgery. If there was an increase of 5 PD or more of esodeviation, the prisms were changed accordingly at 2 weeks. The deviation angle measured at 4 weeks was determined as the surgical target angle. Patients were then divided into increase (≥ 5 PD increase of angle during 4-week PPA) and non-increase groups. Success was defined as either esodeviation of 8 PD or under or exodeviation of 5 PD or under at distance at postoperative 6 months. RESULTS: The increase group included 44 patients (58.7%). The mean deviation angle before PPA was 27.4 PD, and after the 4-week PPA, there was an average increase of 9.4 PD. The success rate was 90.9% in the increase group and 96.8% in the non-increase group (p = 0.316). There were no intergroup differences in preoperative clinical characteristics, esotropia types, postoperative deviation angle or postoperative near stereopsis (p > 0.05). CONCLUSIONS: The results of this study indicated a beneficial effect of 4-week PPA in esotropia of various types, specifically by uncovering the hidden esodeviation in the increase group and simulating the postoperative alignment in both the increase and the non-increase groups.

Surgical treatment outcomes in heavy eye syndrome - a case series.

Results: The study cohort comprised five patients, each presenting with unilateral high axial myopia and classic clinical features of HES, including large angle esotropia, hypotropia, and restricted abduction and supraduction. All patients displayed evident superotemporal globe prolapse on MRI imaging, corresponding to the downward displacement of the LR muscle and medial shift of the SR muscle.Following the surgical procedure, all patients demonstrated significant improvements in both vertical and horizontal deviations, effectively addressing the primary clinical manifestations of HES.Conclusions: In the management of HES, several surgical approaches have been explored, yielding mixed results. Our study, employing the technique of partial muscle splitting and scleral fixation, offers a promising avenue for effectively addressing this challenging condition. By adapting the full loop myopexy technique originally proposed by Yokoyama et al. we achieved satisfactory ocular alignment in all five patients. Notably, this approach mitigates the risk of anterior segment ischemia by preserving the unsecured portions of the SR and LR muscles along with MR retroequatorial myopexy.These findings support the consideration of this surgical technique as a safe and effective option for managing HES, providing both cosmetic and functional improvements to afflicted individuals.

Clinical characteristics and surgical outcomes of acute acquired concomitant esotropia in a tertiary referral centre in Malaysia.

INTRODUCTION: Acute acquired concomitant esotropia (AACE) is an uncommon type of strabismus that occurs due to interruption of fusion. Limited data are available on AACE from Asian countries especially from the Southeast Asian region. We aim to describe the clinical profile and surgical outcomes of AACE patients treated in a tertiary hospital in Malaysia. MATERIALS AND METHODS: We conducted a retrospective study of 20 patients aged 3-26 years who were diagnosed with AACE and attended Hospital Universiti Sains Malaysia, Kelantan, Malaysia, between January 2020 and June 2022 with follow-up periods a minimum of 12 months. Demographic data, clinical features, neuroimaging, surgical intervention, and final ocular alignment outcomes were recorded. RESULTS: The mean age of onset was 9.7±6.6 years. There were equal numbers of males and females in this study. Hypermetropia (45%) was the leading refractive error. Angle of deviation of 50 PD and more was documented in 50% of the patients at distance, and 70% of the patients at near fixation. Fifty per cent had an absence of stereoacuity at presentation. Neuroimaging was performed on 13 patients (65%), and two patients had intracranial pathology. All patients underwent bilateral medial rectus recession during primary surgery. Eighteen patients (90%) experienced excessive near work-related activities for >4 hours per day, and 19 patients (95%) achieved good ocular alignment, restoration of stereoacuity and resolved diplopia after the surgical intervention. CONCLUSION: The mean age of onset was 9.7±6.6 years. Almost half of our patients had uncorrected hypermetropia. Furthermore, 90% of patients had excessive near-work activities, and 95% achieved good post-surgery alignment.

Long-term surgical outcomes of one-muscle vs. two-muscle horizontal strabismus surgery.

PURPOSE: While horizontal strabismus surgery is generally considered to have favorable outcomes, success rates can vary by type of procedure. Our purpose is to compare the long-term outcomes of patients who underwent one-muscle vs. two-muscle horizontal strabismus surgery. METHODS: This is a retrospective study comparing one-muscle to two-muscle strabismus surgery for small to moderate angle horizontal strabismus. Demographic data and eye exam parameters were compared at baseline and postoperatively (6 months up to 6 years). Surgical success was defined as a post-operative angle of 10 PD or less. We also compared outcomes by strabismus type: esotropia vs exotropia and adjusted the analysis for previous strabismus surgery. RESULTS: Out of 89 patients with moderate angle horizontal strabismus (25 PD or less), 17 patients had a one-muscle operation, and 72 patients had two-muscle surgery. The mean age was 14.12 ± 9.30 years and 11.70 ± 11.30 years for the one-muscle and two-muscle groups, respectively (p = .74). The baseline characteristics of both groups were comparable. Follow-up time was 32.82 ± 26.93 months in one-muscle and 37.67 ± 23.81 in two-muscle groups (p = .29). Success rate was 70.6% for the one-muscle group and 68.10% for the two-muscle group (p = .69). Outcomes were similar when divided into esotropia and exotropia. The success rate was not affected by previous strabismus surgeries nor by the initial angle of deviation. CONCLUSION: One-muscle and two-muscle horizontal strabismus surgery had similar long-term outcomes and did not differ by strabismus type nor by angle of deviation.

Doses of medial rectus muscle recessions for divergence insufficiency-type esotropia.

We evaluated whether doses of bilateral medial rectus recessions greater than Parks's tables yielded superior outcomes for adult-onset divergence insufficiency. Forty-two patients underwent bilateral medial rectus recessions. Dose was analyzed as the average total per muscle (surgery + suture adjustment if performed) and compared with the standard dose tables (based on preoperative distance esodeviation), as difference between dose performed and dose indicated by Parks's tables. Each participant was classified as having received either Parks's dose (within 0.5 mm) or a dose greater than Parks's dose. Success was defined as "rarely" or "never" diplopia in distance straight-ahead gaze and reading. For patients classified as success, the mean difference between actual surgical dose performed and Parks's dose was calculated. Success was 91% (29/32) in those receiving greater than Parks's dose versus 67% (6/9) with Parks's dose (difference = 24%; 95% CI, -5% to 60%). The mean surgical dose was 1.0 mm greater than Parks's tables for the 35 successes (at 10 weeks) versus 0.7 mm greater for the 6 failures (difference = 0.4 mm; 95% CI, -0.2 to 0.9). For medial rectus recessions in adult-onset divergence insufficiency-type esotropia, a surgical dose 1 mm greater than Parks's tables, for each muscle, is a reasonable strategy.

Sensory exotropia versus sensory esotropia: A comparative clinical features study.

PURPOSE: This study aimed to compare the preoperative clinical features of patients with sensory esotropia (ET) and sensory exotropia (XT). METHODS: In a retrospective study, the medical records of 13,252 patients who underwent strabismus surgery were reviewed at the Farabi Eye Hospital, Iran, from 2012 to March 2022. There were 1017 patients with sensory horizontal strabismus whose, in their worse eye, had corrected distance visual acuity (CDVA) equal to or <20/160 tested with the Snellen chart. RESULTS: The mean age of patients was 29.0 ± 12.4 years [574 (56.4%) males and 443 (43.6%) females]. Sensory XT and ET were observed in 717 (70.5%) and 300 (29.5%) patients, respectively (P<.001). The mean CDVA in the strabismic and non-strabismic eyes was 1.40 ± 0.75 and 0.05 ± 0.13, respectively (P<.001). Also, the CDVA in the strabismic eyes was significantly worse in the patients with sensory XT than in the patients with sensory ET (P<.001). Sphere and spherical equivalent (SE) components were more hyperopic in both eyes of patients with sensory ET than sensory XT (P<.001). In sensory ET group, the mean horizontal deviation at far and near was significantly higher than the sensory XT group (both P<.001). The prevalence of moderate and severe amblyopia among all patients with sensory strabismus was 274 (26.9%) and 727 (71.5%), respectively (P<.001). There were 398 (39.1%) patients who needed more than one surgery. CONCLUSION: The frequency of sensory XT was about 2.5 times more than the sensory ET. Most patients with sensory ET were operated at a younger age, had better CDVA, more hyperopic spherical and SE, and higher angle of deviation compared with patients with sensory XT. The chance of reoperation in patients with sensory strabismus was about 40%.

Neonatal Macular Hemorrhage in a Term Healthy Infant: 18-Year Follow-up.

Unobstructed binocular vision is required during the critical period of vision development to obtain optimal visual acuity in each eye and binocular stereopsis. In this article, we report 18-year follow-up of a full-term, otherwise healthy infant noted to have dense premacular hemorrhage occluding the visual axis in the left eye on retinal imaging performed 48 hours after birth. Serial examinations by the retina service were performed weekly for 10 weeks as the hemorrhage resolved spontaneously. Shortly thereafter, visual acuity revealed fixation was present, but the mother noted intermittent left eye esodeviation. At 90 days of life, the infant was seen by pediatric ophthalmology and started on 1 to 2 hours patching of the right eye daily for the esotropia, which was maintained through 24 months. At 18 years of age, the patient had orthophoria alignment, no spectacle correction, vision of 20/20 in the right eye and 20/25 in the left eye, and normal binocularity and stereopsis. Intermittent esodeviation on the left eye was observed when the patient was fatigued. Early identification of a visual axis occlusion led to prompt referral for the esotropia and initiation of patching therapy. This patient ultimately achieved a very favorable visual functional outcome that may not have been possible without early detection and management. This case report describes the longest-term published follow-up of a neonatal macular hemorrhage. [Ophthalmic Surg Lasers Imaging Retina 2024;55:354-357.].

Mechanisms for Positive Bielschowsky Head Tilt Testing in Horizontal Strabismus.

PURPOSE: To elucidate the induced effects of horizontal strabismus on the Bielschowsky Head Tilt Test (BHTT). DESIGN: Prospective clinical study. METHODS: Prospective analysis of BHTT testing in 85 patients with exotropia and 71 patients with esotropia who were examined in a strabismus clinic. RESULTS: Eighty-four of 85 patients with exotropia (98.82%) showed a positive BHTT with an induced hyperdeviation on the side of the tilt (to both sides in 67% and to one side in 32%). Fifty-seven of 71 patients with esotropia (80.2%) showed a positive BHTT with an induced hypodeviation on the side of the tilt (to both sides in 57.7% and to one side in 22.5%). These induced vertical deviations were greater in patients with larger horizontal deviations and in those with constant rather than intermittent deviations; however, they were not influenced by the presence or absence of associated primary oblique muscle overaction. CONCLUSIONS: Exotropia and esotropia produce hyperdeviations during BHTT testing, with a hyperdeviation on the side of the tilt observed in patients with exotropia, and hypotropia on the side of the tilt observed in patients with esotropia. These diametrical results are not attributable to any preexistent alteration of neurologic output inherent to these two forms of horizontal strabismus or to associated torsion. Rather, they arise directly from the altered anatomical positions of the two eyes, which cause the eyes to approximate their visual axes more closely to the vertical rectus muscles (in exotropia) and the oblique muscles (in esotropia), enabling the vertical actions of specific cyclovertical muscles to predominate in response to altered utricular output generated by the BHTT.

[The timing and challenges of early intervention for infantile esotropia].

Infantile esotropia is a common ophthalmic disease in children. A lot of clinical and basic research evidence suggests that early surgery enhances sensory and ocular motor development. However, the proper timing of surgery has been debated for decades. In addition, there is more likely instability of deviation in the preoperative evaluation of infants, and even if the patient achieved alignment after surgery, the defects in binocular vision may accompany for a lifetime. This article analyzes the difficulties and key points of early intervention for infantile esotropia, aiming to provide scientific ideas for the early treatment of children with infantile esotropia in China.

Alteration of Neurotrophic Factors and Innervation in Extraocular Muscles of Individuals With Concomitant Esotropia.

Purpose: To determine whether neurotrophic factors and innervation in extraocular muscles (EOMs) were altered in different types of concomitant esotropia, and to explore the possible association between neurotrophic factors and innervation of EOMs in humans. Methods: Patients with concomitant esotropia who required strabismus surgery were recruited from January to December 2022. Lateral rectus EOMs were obtained from patients, and controls were obtained from deceased organ donors. Immunofluorescence (IF) was performed to detect innervation of EOMs (neurofilament and synaptophysin), and immunohistochemistry (IHC) was used to detect the neurotrophic factors insulin-like growth factor-1 (IGF-1), brain-derived neurotrophic factor (BDNF), glial cell-derived neurotrophic factor (GDNF), and neurotrophin-3 (NT-3). The positive IHC results were further verified using western blotting (WB). One-way ANOVA followed by a Dunnett's multiple comparison post hoc test was used for continuous variables and the χ2 test for categorical variables. Spearman correlation analysis was used for the correlation analysis. Results: We collected lateral rectus EOM samples from acute and chronic types of concomitant esotropia and controls. Consistent with IHC, WB showed that IGF-1 was significantly increased in patients with acute acquired comitant esotropia or essential infantile esotropia compared with controls. In IF, synaptophysins were significantly increased only in acute acquired comitant esotropia compared with controls. Furthermore, Spearman correlation analysis showed that the correlation between IGF-1 and synaptophysin was borderline (P = 0.057) for patients with acute acquired comitant esotropia. Conclusions: Our study highlights the role of IGF-1 and altered innervation of EOMs in acute acquired comitant esotropia, suggesting that an effect of increased IGF-1 on nerve innervation may temporarily cause a compensatory increase in the strength of lateral rectus muscles.

Strabismus management in retinoblastoma survivors.

PURPOSE: To report the result of strabismus surgery in eye-salvaged retinoblastoma (Rb) patients. METHODS: A retrospective case series including 18 patients with Rb and strabismus who underwent strabismus surgery after completing tumor treatment by a single pediatric ophthalmologist. RESULTS: A total of 18 patients (10 females and 8 males) were included with a mean age of 13.3 ± 3.0 (range, 2-39) months at the time tumor presentation and 6.0 ± 1.5 (range, 4-9) years at the time of strabismus surgery. Ten (56%) patients had unilateral and 8(44%) had bilateral involvement and the most common worse eye tumor's group was D (n = 11), C (n = 4), B (n = 2) and E (n = 1). Macula was involved by the tumors in 12 (67%) patients. The tumors were managed by intravenous chemotherapy (n = 8, 47%), intra-arterial chemotherapy (n = 7, 41%) and both (n = 3, 17%). After complete treatment, the average time to strabismus surgery was 29.9 ± 20.5 (range, 12-84) months. Except for one, visual acuity was equal or less than 1.0 logMAR (≤ 20/200) in the affected eye. Seven (39%) patients had exotropia, 11(61%) had esotropia (P = 0.346) and vertical deviation was found in 8 (48%) cases. The angle of deviation was 42.0 ± 10.4 (range, 30-60) prism diopter (PD) for esotropic and 35.7 ± 7.9 (range, 25-50) PD for exotropic patients (P = 0.32) that after surgery significantly decreased to 8.5 ± 5.3 PD in esotropic cases and 5.9 ± 6.7 PD in exotropic cases (P < 0.001). The mean follow-up after surgery was 15.2 ± 2.0 (range, 10-24) months, in which, 3 (17%) patients needed a second surgery. CONCLUSION: Strabismus surgery in treated Rb is safe and results of the surgeries are acceptable and close to the general population. There was not associated with tumor recurrence or metastasis.

A Comparison of Chemodnervation to Incisional Surgery for Acute, Acquired, Comitant Esotropia: An International Study.

PURPOSE: To compare the efficacy of botulinum toxin injections to strabismus surgery in children with acute, acquired, comitant esotropia (ACE), and to investigate factors predicting success. DESIGN: International, multi-center nonrandomized comparative study METHODS: Setting: Cloud-based survey. STUDY POPULATION: Children aged 2 to 17 years who underwent a single surgical intervention for ACE. INTERVENTIONS: Botulinum toxin injection ("chemodenervation" group) or strabismus surgery ("surgery" group). MAIN OUTCOME MEASURES: Primary measure: success rate at 6 months in propensity-matched cohort, defined as total horizontal deviation of 10 prism diopters or less with evidence of binocular single vision. Secondary measure: Risk factors for poor outcomes in the full cohort. RESULTS: Surgeons from 19 centers contributed. There were 74 patients in the chemodenervation group and 97 patients in the surgery group. In the propensity-matched data (n = 98), success rate was not significantly different at 6 months (70.2% vs 79.6%; P = .2) and 12 months (62.9% vs 77.8%; P = .2), but was significantly lower in the chemodenervation group at 24 months (52% vs 86.4%; P = .015). Irrespective of treatment modality, treatment delay was associated with lower success rates at 6 months, with median time from onset to intervention 4.5 months (interquartile range (IQR): 2.1, 6.7) in the success group and 7.7 months (IQR: 5.6, 10.1) in the failure group (P < .001). CONCLUSIONS: In children with ACE, success rate after chemodenervation was similar to that of surgery for up to 12 months but lower at 24 months. Those with prompt intervention and no amblyopia had the most favorable outcomes, regardless of treatment modality.

The incidence, clinical features, and management of essential infantile esotropia in the United Kingdom. A British Ophthalmology Surveillance Unit (BOSU) study.

BACKGROUND/OBJECTIVES: A national study was undertaken through the British ophthalmology surveillance unit (BOSU) to determine the incidence, presenting features and management of essential infantile esotropia (EIE) in the UK. METHODS: Data from a prospective national observational study of newly diagnosed EIE presenting to clinicians in the United Kingdom over a 12-month period were collected. Cases with a confirmed diagnosis by a clinician of a constant, non-accommodative esotropia ≥20 prism dioptres (PD), presenting at ≤12 months, with no neurological or ocular abnormalities were identified through BOSU. Follow-up data were collected at 12 months. RESULTS: A total of 57 cases were reported giving an incidence of EIE of 1 in 12,828 live births. The mean age of diagnosis and intervention were 7.05 ± 2.6 months (range 2-12) and 14.7 ± 4.9 months (range 6.5-28.1), respectively. Management was surgical in 59.6%, botulinum toxin alone in 22.8%, and 17.5% were observed. The preoperative angle of esotropia was smaller in the observation group (P = 0.04). The postoperative angle of esotropia was not statistically significant between botulinum toxin or surgery (P = 0.3), although the age of intervention was earlier in the botulinum group (P = 0.007). Early intervention (before 12 months of age) did not influence the post-intervention motor outcomes between 0 and 10 prism dioptres of esotropia (P = 0.78). CONCLUSIONS: The incidence of EIE in the UK is considerably lower than reported in other population-based studies. The preferred method of treatment was surgical with earlier intervention in those treated with botulinum toxin. An early age of intervention (<12 months) did not influence motor outcomes.

Clinical features and change in incidence of acute acquired comitant esotropia: a 15-year single-centre study in South Korea.

BACKGROUND/OBJECTIVES: We investigated the clinical features and change in incidence of AACE in South Korea. SUBJECTS/METHODS: We reviewed the medical records of AACE patients who visited the Strabismus Clinic of at a tertiary referral hospital from 2007 to 2021. Clinical features were retrieved, including age at onset, angle of deviation, refractive errors, neuroimaging findings, and treatment outcomes. For each year, the proportion of new AACE patients among all new patients who visited the clinic, and the ratio of new AACE patients to new intermittent exotropia (IXT) patients, were analysed to estimate the incidence of AACE. RESULTS: Overall, 59 patients were included in the study. The mean age of the patients was 24.7 ± 9.3 years; the incidence of AACE was highest in teenagers and young adults. No patients had a history of visual occlusion, recent physical or psychological stress, or uncorrected myopia, unlike to classic AACE; moreover, no patients exhibited abnormalities in neuroimaging. There was a significantly increasing trend in the proportion of new AACE patients among all new patients (linear regression analysis, R2 = 0.778, p < 0.001). There was also a significantly increasing trend in the ratio of new AACE patients to new IXT patients (R2 = 0.803, p < 0.001). CONCLUSIONS: A new type of AACE, distinct from the classic types, is increasingly common in South Korea; this increasing incidence also appears to be a global phenomenon. Large-scale investigations are needed to define the exact clinical features, incidence, and pathophysiology of this new type of AACE.

Corneal tomography changes following major (6 mm) medial rectus muscle recession: a prospective cohort study using Pentacam®.

INTRODUCTION: The aim of this study is to evaluate changes in corneal astigmatism, axial anterior corneal curvature, as well as changes in the anterior chamber depth and central corneal thickness, 2 months following the unilateral recession of medial rectus muscle in children. METHODS: Thirty-three children with esotropia were prospectively evaluated following unilateral medial rectus muscle recession, using Pentacam®. Comparisons were made between the operated and fellow unoperated eyes, pre, and postoperatively. 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®). ANOVA model was used to examine the interaction between age or central corneal thickness and postoperative changes in anterior and posterior surface corneal astigmatism. RESULTS: In the intervention group, changes in anterior and posterior corneal surface astigmatism were statistically significant, with a mean increase of 0.59Dx92 and 0.08Dx91, respectively. In the mid-peripheral corneal zone, there is an increase in the radius of anterior corneal axial curvature more evident nasally 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.

Magnetic resonance imaging findings of high myopic strabismus with sagging eye-like symptoms, heavy eye syndrome, and non-highly myopic eyes with sagging eye syndrome.

INTRODUCTION: Progressive esotropia accompanied by restricted abduction and supraduction due to high myopia is known as esotropia fixus with high myopia or heavy eye syndrome (HES). Some conditions, such as sagging eye syndrome (SES), show esotropia for distance or cyclovertical strabismus with no abduction limitations despite highly myopic eyes. We evaluated the magnetic resonance imaging (MRI) findings and clinical features of HES, high myopia with SES-like symptoms (highly myopic SES), and SES. METHODS: We reviewed all patients diagnosed with HES, highly myopic SES, and SES who underwent MRI of the orbits and brain over 6 years. To quantitatively assess the orbital anatomy, we compared the conditions of the superior rectus muscle (SR), lateral rectus muscle (LR), and inferior rectus muscle (IR) using orbital MRI among the three groups. RESULTS: Among the 14 patients (27 eyes) with high myopia, 5 (9 eyes) had HES, and 9 (18 eyes) had highly myopic SES. Eleven patients (22 eyes) with SES were also compared with these 14 patients. The mean axial length was 29.6 ± 1.0 mm in participants with HES, 29.0 ± 1.5 mm in those with HES-SES, and 23.7 ± 0.9 mm in those with SES. The average distance esotropia was 48.0 ± 19.9Δprism, 4.6 ± 1.5Δprism, and 6.1 ± 4.6Δprism for participants with HES, highly myopic SES and SES, respectively. The average distance hypertropia was 5.3 ± 5.9Δprism in participants with highly myopic SES and 4.8 ± 2.7Δprism in those with SES. The mean vertical angle of the LR was 32.6 ± 10.8°, 18.1 ± 5.4°, and 14.6 ± 6.8°; the mean tilting angle of the LR was 31.6 ± 9.2°, 15.9 ± 6.0°, and 13.8 ± 5.9°; and the mean displacement angle between the LR and SR was 152.3 ± 16.7°, 125.0 ± 7.1°, and 112.5 ± 7.5° for participants with HES, highly myopic SES and SES, respectively. The LR-SR displacement angle in HES-SES was significantly larger than in SES (p < .001) but the vertical and tilting angles were not. Also, the IR shift showed no significant difference with HES-SES and HES (5.8 ± 1.4 mm and 5.3 ± 1.2 mm) but not with SES (4.0 ± 0.8 mm) (p < .0001). DISCUSSION: SES-like symptoms can develop in highly myopic eyes; however, MRI showed that the state of the LR muscle in highly myopic SES deviated almost similarly to that in SES; however, the eyeball was more dislocated than in SES. This may be useful in deciding the appropriate operative procedure.