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.

Race, Ethnicity, Insurance, and Population Density Associations with Pediatric Strabismus and Strabismic Amblyopia in the IRIS® Registry.

PURPOSE: To evaluate the associations of sociodemographic factors with pediatric strabismus diagnosis and outcomes. DESIGN: Retrospective cohort study. PARTICIPANTS: American Academy of Ophthalmology IRIS® Registry (Intelligent Research in Sight) patients with strabismus diagnosed before the age of 10 years. METHODS: Multivariable regression models evaluated the associations of race and ethnicity, insurance, population density, and ophthalmologist ratio with age at strabismus diagnosis, diagnosis of amblyopia, residual amblyopia, and strabismus surgery. Survival analysis evaluated the same predictors of interest with the outcome of time to strabismus surgery. MAIN OUTCOME MEASURES: Age at strabismus diagnosis, rate of amblyopia and residual amblyopia, and rate of and time to strabismus surgery. RESULTS: The median age at diagnosis was 5 years (interquartile range, 3-7) for 106 723 children with esotropia (ET) and 54 454 children with exotropia (XT). Amblyopia diagnosis was more likely with Medicaid insurance than commercial insurance (odds ratio [OR], 1.05 for ET; 1.25 for XT; P < 0.01), as was residual amblyopia (OR, 1.70 for ET; 1.53 for XT; P < 0.01). For XT, Black children were more likely to develop residual amblyopia than White children (OR, 1.34; P < 0.01). Children with Medicaid were more likely to undergo surgery and did so sooner after diagnosis (hazard ratio [HR], 1.23 for ET; 1.21 for XT; P < 0.01) than those with commercial insurance. Compared with White children, Black, Hispanic, and Asian children were less likely to undergo ET surgery and received surgery later (all HRs < 0.87; P < 0.01), and Hispanic and Asian children were less likely to undergo XT surgery and received surgery later (all HRs < 0.85; P < 0.01). Increasing population density and clinician ratio were associated with lower HR for ET surgery (P < 0.01). CONCLUSIONS: Children with strabismus covered by Medicaid insurance had increased odds of amblyopia and underwent strabismus surgery sooner after diagnosis compared with children covered by commercial insurance. After adjusting for insurance status, Black, Hispanic, and Asian children were less likely to receive strabismus surgery with a longer delay between diagnosis and surgery compared with White children. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

A rare case of intramuscular orbital amyloidosis presenting as progressive esotropia in an adult.

Orbital amyloidosis is an uncommon entity. Lacrimal gland, orbital soft tissue and extraocular muscles are the usual sites of involvement. Deposition of amyloid in the extraocular muscle can be either isolated or associated with systemic amyloidosis. We describe a case of a 43-year-old male with isolated amyloid infiltration of the right lateral rectus muscle presenting as a progressive esotropia. The case was initially misdiagnosed as lateral rectus palsy and myositis due to non-specific radiological features of the entity. The diagnosis was confirmed by a biopsy. Intramuscular Botulinum toxin injection, was administered to the right medial rectus to alleviate diplopia temporarily, and strabismus surgery was planned at a later stage. Amyloid deposition is a rare cause of extraocular muscle enlargement. Histopathology is confirmatory. Screening for systemic amyloidosis is mandatory in all cases.

Clinical features, etiological reasons, and treatment results in patients who developed acute acquired nonaccomodative esotropia.

PURPOSE: To evaluate the clinical features, possible etiological reasons, and treatment results in children who developed acute acquired comitant esotropia (AACE) without strabismus in previous years. METHODS: Medical records of the patients who were diagnosed with AACE between July 2017 and June 2021 were retrospectively reviewed. The children with ocular and orbital pathology, hypermetropia > 2.00 diopters, and anisometropia > 1.00 diopters were not included in the study. Possible etiological factors that could cause esotropia, treatment results, motor, and sensory functions were investigated. RESULTS: The mean age at first admission, and the onset of AACE, was 8.8 ± 2.9 (4-13) years of three female (23.1%) and 10 male (76.9%) cases. The causes of AACE were determined to be occlusion of the eye due to corneal foreign body removal in one (7.7%), emotional stress in one case (7.7%), and excessive close work, on computer and smartphone screens in the other 11 cases (84.6%). Orthotropia was achieved in cases who underwent strabismus surgery (n = 10) and in cases using the prism (n = 2); except for one case, all (92.3%) achieved binocular single vision (100 s/arc stereopsis and fusion) after treatment, while there was no binocular single vision in any of the cases before treatment. CONCLUSIONS: Acute acquired comitant esotropia is a rare clinical entity. Successful motor and sensory outcomes can be achieved by strabismus surgery or by prism therapy. It is critical to investigate the patients with AACE in terms of intracranial pathologies, although rarely seen.

Botulinum toxin treatment for bielschowsky acquired commitant esotropia in adults.

BACKGROUND: Many researchers have noticed that there is an increasing trend of Bielschowsky acquired comitant esotropia (ACE) in recent years related to excessive near work, but the exact pathogenesis and treatment methods have not been reported yet. Therefore, we aimed to characterize the clinical features of this ACE in adults and to evaluate the efficacy of botulinum toxin (BTX) injections in these patients. METHODS: This was a prospective consecutive case series of 47 patients with Bielschowsky ACE. BTX was injected bilaterally into the medial rectus muscle of 45 patients, and twenty-seven of them (27/45) completed 10 months of follow-up after their last injection. Angle of deviation, fusion, stereopsis, subjective assessment of diplopia were documented before and after BTX treatment, and repeated measures data were compared by the Wilcoxon signed-rank test or Analysis of variance. The relationship between BTX dosage and corrected esotropia was explored by the Regression analysis. Meanwhile, possible risk factors for ACE including time spent on near work, refraction error, patients' personality, glasses wearing habits and duration of symptoms were recorded and analyzed with General Linear Models. RESULTS: The patients aged 32.32 ± 10.96 (range 15-53) years spent 8.34 ± 2.38 h on near work each day, and most myope habitually removed their glasses at near. Their chief complaint was distance diplopia, with more significant esotropia at distance (around 20 PD) than at near. This series of patients also exhibited perfectionist tendencies. However, most patients achieved orthophoria after BTX treatment, only with a mild residual esotropia (+ 3.96 ± 5.79 PD), which left them asymptomatic most of the time. CONCLUSION: This group of ACE patients was characterized by diplopia with more significant esotropia at distance. Besides excessive near-work, habitually removing myopic glasses and perfectionist tendencies may also contribute to this type of ACE. Fortunately, bilateral BTX injection safely and effectively reduced the esotropia with complete resolution of symptoms, especially for those treated at an early stage.

The effect of different types of convergent strabismus on horizontal eye movements.

PURPOSE: To investigate the effect of different types of convergent strabismus on horizontal eye movements and compare data with healthy control subjects. MATERIALS AND METHODS: This prospective, cross-sectional study included 38 patients with convergent strabismus (16 fully accommodative, 13 partially accommodative and 9 non-accommodative esotropia) and 19 age-matched control subjects. All of the participants had a detailed ophthalmological examination including visual acuity assessment, cover-uncover prism test, slit lamp, and indirect ophthalmoscopy examination. Videonystagmography (VNG) was used for the evaluation of horizontal eye movements such as saccadic accuracy, velocity, latency, and smooth pursuit velocity gain. RESULTS: The saccadic accuracy in the rightward direction was lower in the fully accommodative esotropia group compared to the partially accommodative esotropia group in the right eye (p = 0.002). The saccadic latency in the rightward direction was longer in the fully accommodative esotropia group compared to the control group (p = 0.008) and smooth pursuit velocity gain in the leftward direction was lower in the partially and non-accommodative esotropia group compared to the control group in binocular recording (p = 0.004, p = 0.001, respectively). There was no difference in the saccadic velocity among the study groups (p > 0.05). Finally, asymmetry of saccadic velocity and latency was observed between right- and leftward directions in the partially accommodative esotropia group in the right eye (p = 0.003, p = 0.008, respectively). CONCLUSION: This study demonstrated that horizontal eye movements may vary in different types of convergent strabismus. VNG may be an auxiliary tool to the clinical examination in differentiating fully or non-accommodative esotropia.

[Botulinum therapy for acute esotropia]. / Botulinoterapiya v lechenii ostro voznikshei ezotropii.

PURPOSE: To determine the effectiveness of the use of botulinum toxin type A in the treatment of acute esotropia in children. MATERIAL AND METHODS: A retrospective analysis of the results of using botulinum toxin type A in the treatment of acute convergent strabismus in 16 children was performed. Children's ages ranged from 3 to 15 years. Botulinum toxin was injected into the medial rectus muscles. In 6 patients with acute esotropia, botulinum toxin was injected into the internal rectus muscle of both eyes, in the rest of patients the toxin was injected into one eye. Two patients underwent chemodenervation of extraocular muscles twice. The injected dose of botulinum toxin (from 1 to 5 U) was chosen depending on the strabismus angle, the patient's age, and the duration of the disease. In order to form binocular vision, all patients underwent orthopto-diploptic treatment. The observation period lasted 12 to 18 months. RESULTS: One month after chemodenervation, the orthoposition of the eyes was persistently restored in 7 children (43.75%). Esodeviation angle decreased steadily to 2 degrees in 4 patients (25%). A second injection of botulinum toxin was required to achieve orthotropy in 2 patients (12.5%) 4-6 months after chemodenervation. An increase of esodeviation angle was recorded in 3 patients (18.75%), which required classical surgical treatment of strabismus. One month after the injection, unstable binocular vision developed in 11 children (68.75%). After 1 year, binocular vision was successfully formed 13 patients (81.25%). CONCLUSION: Chemodenervation in the majority of children with acute esotropia led to persistent orthoposition of the eyes. This created favorable conditions for the restoration of binocular vision during subsequent orthopto-diploptic treatment.

Pseudo-Gaze Deviation Resulting From Positive Angle Kappa and Esotropia.

ABSTRACT: A 6-year-old boy was referred for constant right gaze deviation. Rather than a gaze deviation, he constantly seemed to look on the left side of any displayed target. Examination revealed the association of a highly positive angle Kappa and an esotropia of equal values. He also exhibited signs of ocular albinism with no associated infantile nystagmus syndrome. The X-linked ocular albinism was confirmed genetically, explaining the presence of a positive angle Kappa. A highly positive angle Kappa can be associated with a convergent strabismus; in case both values offset each other, this can result in a constant "sidelooking," which should not be confused with a gaze deviation.

Clinical Classification of Acquired Concomitant Esotropia.

BACKGROUND: Classification and management of acquired concomitant esotropia is controversial. We sought to establish a simple clinical classification in order to determine in which cases further investigations in search of underlying pathologies are necessary. PATIENTS AND METHODS: Observational retrospective study of the files of 175 consecutive patients examined in our unit between 2009 and 2018 for acute convergent strabismus. One hundred and nine patients were selected, after exclusion of infantile, incomitant, or mechanical esotropias, residual esotropias, and patients examined on a single occasion. All patients received a complete orthoptic and ophthalmological examination. We grouped the patients according to their common characteristics. RESULTS: We established the following categories: 1. Acute esotropia of large angle (20 to 45 prism diopters [PD]), accompanied by mild hyperopia (mean 1.2 D) in children (n = 16) and moderate myopia (mean 3.7 D) in adolescents and adults (n = 13). 2. Decompensated micro-esotropia, which is distinguished from the other categories by the presence of abnormal retinal correspondence (n = 33). 3. Decompensated esophoria, with intermittent deviations of 5 to 30 PD, esotropia being compensated part of the time (n = 25). 4. Esotropia present only at a distance in patients over 50 years of age (n = 20). 5. Small-angle esotropia (< 15 PD) greater at a distance, associated with oculomotor cerebellar syndrome (n = 2). Complementary examinations (MRI or CT scan) were performed on 21 patients, leading to the discovery of a posterior fossa astrocytoma in a 4-year-old boy. CONCLUSIONS: The recognition of decompensated micro-esotropia and esophoria, as well as distance esotropia of the elderly, avoids unnecessary additional investigations, which are indicated in any type of acute comitant strabismus if associated with any neurological sign or symptom (e.g., headaches, nausea, vertigo, imbalance, poor coordination, nystagmus, or papilledema). In the absence of neurological findings, there is no consensus about the indication of neuroimaging in large-angle acquired concomitant esotropia, but long-term follow-up of patients that do not undergo neuroimaging is strongly recommended in order to identify later occurring intracranial diseases. This is of particular importance with children.

[Acute Acquired Comitant Esotropia Type 2 - A Retrospective Analysis]. / Akut erworbene konkomitante Esotropie Typ 2 ­ eine retrospektive Analyse.

BACKGROUND: Acute acquired comitant esotropia (AACE) is an uncommon form of strabismus. The main characteristics of AACE Type 2 in childhood are: acute onset of strabismus around 3 years of age, large and comitant angle of strabismus, absence of accommodative component, hyperopia of not more than 3 dpt, and measurable stereopsis. Strabismus surgery is urgently indicated in AACE Type 2 in order to avoid maldevelopment or loss of stereopsis. Therefore, in order to better describe the characteristics of AACE Type 2, we performed a retrospective analysis of patients previously seen in our clinic. PATIENTS AND METHODS: Retrospective analysis of data from patients who underwent strabismus surgery between October 2011 and September 2019 due to suspected AACE Type 2 could be confirmed during postoperative visits by evaluating ocular alignment and stereopsis at our hospital. Analysed data included: age and symptoms at first visit, visual acuity, refractive status, correction by glasses, age at surgery, period of time between first symptoms and surgery, surgical procedure, stereopsis and angle of strabismus (before surgery and 1 day, 3 months, and 12 months after surgery). Ethical approval was obtained from the Cantonal Ethics Committee of Zurich. RESULTS: 18 patients (12 male, 6 female) with mean hyperopia of 1.4 ± 0.6 dpt were identified as meeting the inclusion criteria during the defined time period. Amblyopia was present at first assessment in two patients. Strabismus surgery was performed at 2.0 to 11.1 years of age and between 0.4 and 24.6 months after onset of symptoms. Surgery was performed within 6 months after onset of symptoms in 12/18 children. Before surgery, angle of strabismus at near was measured as 38 ± 10 prism diopters (PD) and was reduced after surgery to 3 ± 3 PD at 3 months and 2 ± 2 PD at 12 months. Stereopsis was confirmed in 5/18 patients one day after surgery and in 18/18 patients 12 months after surgery. CONCLUSION: Our analysis showed that our patients with diagnosis of AACE Type 2 had mild hyperopia and large comitant non-accommodative esotropia; prognosis for recovery of stereopsis is excellent. Preoperative amblyopia does not exclude the diagnosis of AACE Type 2. Therapeutic intervention is advisable within a short period of time after first symptoms and the diagnosis of AACE Type 2.

Acute acquired concomitant esotropia associated with myopia: is the condition related to any binocular function failure?

PURPOSE: To evaluate the sensory motor state, accommodation, and accommodative convergence to accommodation ratio (AC/A) in a cohort of non-amblyopic myopes with acquired concomitant esotropia (Bielschowsky esotropia (BE)). METHODS: Refraction, near and far deviation, fusional amplitude (FA), near point of accommodation (NPA), AC/A (gradient method), and stereopsis were measured in a cohort of 26 patients (25 phakic and 1 pseudophakic, age: 14-60 years) with BE, prospectively recruited from January to September 2019 at St. Orsola-Malpighi Hospital, Bologna, Italy. The Pearson's correlation coefficient was used to correlate distance with near deviation, distance with near divergence FA and angle of deviation with FA (statistical significance: p values < 0.05). RESULTS: Myopia range was 0-17.5 diopters (D) spherical equivalent (mean: 4.4 D). A positive correlation resulted between distance (mean: 23.7 prism diopters/PD, range: 4-40 PD) and near (mean: 23.7 PD, range: 2-45 PD) deviation (p < 0.00001) and between distance (mean: 12.6 PD, range 0-34 PD) and near (mean: 17.0 PD, range 3-36 PD) divergence FA (p < 0.00001). A non-significant correlation resulted between angle of deviation and divergent FA at near (p = 0.07) and distance (p = 0.13) fixation. NPA was within normal limits for age. AC/C ratio range was 0-8 (mean: 3). Twenty-three patients showed Randot stereopsis. CONCLUSIONS: BE shows high variability in the age of onset, degree of associated myopia, AC/A, and divergent FA. A little stronger near divergent FA can justify the better compensation at near fixation. These results show that uncorrected myopia, accommodation, and divergence paralysis do not concur with the genesis of BE.

Management of stretched scar- induced secondary strabismus.

BACKGROUND: To determine characteristics and management of consecutive or recurrent strabismus secondary to stretched scar. METHODS: This is a retrospective review of all patients diagnosed with late secondary consecutive or recurrent strabismus due to stretched scar from 2012 to 2017. The diagnosis of stretched scar was made in any case of late (≥ 1 month) consecutive or recurrent strabismus associated with underaction of the previously operated muscle. The diagnosis was confirmed intraoperatively by negative forced duction test and the characteristic appearance of the scar tissue. Surgical correction involved excision of the scar tissue with muscle re-attachment to the sclera using non-absorbable sutures. Study parameters include improvement in secondary deviations, degree of muscle underaction and diplopia. RESULTS: 21 consecutive and 6 recurrent cases of stretched scar -induced strabismus were identified and all cases were associated with variable degrees of limited ocular duction. After surgical correction of the stretched scar, consecutive deviations in the form of consecutive esotropia and exotropia were corrected by means of 26.1PD and 65.6PD while recurrent deviations in the form recurrent exotropia and recurrent hypertropia were corrected by means of 34.3PD and 11PD respectively with significant improvement of limited ocular ductions. 21 patients had diplopia at presentation and all were improved after surgery. CONCLUSION: management of stretched scar -induced secondary strabismus by excision of the stretched scar and muscle fixation to the sclera using non-absorbable sutures significantly corrects secondary deviations and improves limitation of ocular duction.

Differential Diagnosis of Acquired Esotropia in the Elderly. / Differenzialdiagnose der erworbenen Esotropie im Alter.

AIM: To provide an overview of the differential diagnoses of acquired esotropia that occur in the elderly and to facilitate their differentiation in everyday clinical practice. METHODS: The data of all patients who presented in our outpatient university department for strabology and neuroophthalmology from March 2014 to October 2015 due to esotropia with diplopia with onset after age 50 were evaluated retrospectively. Exclusion criteria were a known strabismus before the age of 50 and/or vertical deviations in the primary position. Anamnestic characteristics, accompanying findings and orthoptic parameters, were analysed. RESULTS: 85 patients were included in the study, 42 of them female and 43 male. The following diagnoses were made: abducens nerve palsy (n = 34, 3 of them both sides), esotropia due to myopia magna (n = 12), esotropia with accompanying neurological symptoms (n = 6) and other etiology (n = 5). In 4 cases, the diagnosis was still unclear at the end of the study. In 24 patients, none of the above diagnoses existed and the diagnosis of "sagging eye syndrome" (ETSAG) was made. The abducens nerve palsy typically showed a sudden onset of double vision, slowed abduction saccades and asymmetrical abduction ability. With unilateral abducens nerve palsy, the esotropia increased continuously from the view to the unaffected side through the primary position to the view to the affected side. Patients with ETSAG and myopia-associated esotropia, on the other hand, reported a gradual onset of double vision, showed normal abduction saccades and a slightly reduced abduction ability. The squint angle often increased slightly to both sides. Esotropia with accompanying neurological symptoms was rare and was seen in various underlying diseases. CONCLUSIONS: The kind of onset of the double vision, the quality of the saccades, the incomitance pattern and the ability to abduct are important parameters for the etiological assignment of an esotropia in the elderly. The characteristics of the individual diagnoses are described and differential diagnostic aspects are discussed.

Infrared photographs with a selective wavelength filter to diagnose small-angle esotropia in young children.

PURPOSE: To validate the effectiveness of the selective wavelength filter analysis with infrared photographs for diagnosing small-angle esotropia in children under age 4. METHODS: This is a retrospective, observational, case-control study. A total of 83 esotropes with an esodeviation of ≤ 16 prism diopters (PD) and 75 orthotropic controls under 4 years of age were included. Full-face infrared photographs were taken with a selective wavelength filter in front of either eye. The angles of esodeviation on photographs were measured with the three-dimensional Strabismus Photo Analyzer. The alternate prism and cover test or the Krimsky test were repeatedly performed to measure ocular alignment. RESULTS: The testability of infrared photographs using selective wavelength filters in children under 4 years of age was 85.6%. The mean angle of esodeviation was 11.3 ± 4.0 PD by manual measurements and 11.5 ± 4.4 PD by the infrared photograph analysis. Manual measurements and the infrared photograph analysis showed a strong positive correlation (R = 0.815, P < 0.001). The sensitivity and specificity of the infrared photograph analysis for detecting small-angle esotropia were 95.2% and 77.9%, respectively, with a cutoff value of 4.0 PD. CONCLUSIONS: The automated infrared photograph analysis was simple and effective for diagnosing small-angle esotropia in young children.

Magnetic resonance imaging findings of age-related distance esotropia in Japanese patients with high myopia.

PURPOSE: This study aimed to investigate the characteristics of the extraocular muscles and the orbital connective tissue pulleys in Japanese patients with age-related distance esotropia (ARDE) and high myopia using magnetic resonance imaging (MRI). METHODS: This was a retrospective case-series study. High-resolution coronal MRI scans of 12 orbits were obtained in 6 patients with ARDE and high myopia (age range: 51-69 years). We analyzed the images to determine the positions of the rectus muscle pulleys relative to the center of the globe, the integrity of the lateral rectus-superior rectus muscle (LR-SR) band, and the LR angle (the angle between the major axis of the LR and the vertical plane). RESULTS: The distance esotropia ranged from 4 to 25∆, and 3 cases exhibited vertical deviations. The mean (±standard deviation (SD)) axial length was 28.5 (± 1.6) mm. The mean positions of the medial rectus muscle pulley and LR pulley were 1.3 mm inferior and 1.4 mm inferior, respectively, to those seen in the normal control group in our previous study (P = 0.002 and P = 0.05, respectively). All 12 orbits had abnormal elongated LR-SR bands, and 8 orbits (67%) displayed ruptured LR-SR bands. The LR angle (mean±SD; 18.8° ± 8.5°) increased significantly with the inferior displacement of the LR pulley (R2 = 0.77, P = 0.0002). CONCLUSIONS: Inferior displacement of the LR pulley and abnormal LR-SR bands were seen in Japanese ARDE patients with high myopia, as was found in ARDE patients without high myopia. The LR angle might be useful for judging the degree of LR pulley displacement.

Optic disc shape in patients with long-lasting unilateral esotropia and exotropia.

BACKGROUND: Horizontal eye movements have been proposed to induce biomechanical stress and strain on optic nerve head. Since strabismus may lead to sustained adduction or abduction, we investigate the effects of long lasting unilateral horizontal strabismus on the morphology of optic disc. METHODS: The observational cross-sectional study included patients with unilateral constant horizontal strabismus lasting for more than two years. The patients underwent an ophthalmological examination including refraction and morphometry of the optic nerve head. A prism cover test using right angle glass prism was performed to measure the magnitude of the ocular deviation. RESULTS: The study included 70 patients with a unilateral constant strabismus (35 esotropic patients, 35 exotropic patients) with a mean age of 26 ± 19 years, mean refractive error of - 0.72 ± 3.3 diopters, mean axial length of 23.8 ± 1.7 mm, and a mean angle of deviation of 87 ± 36 prism diopters (Chinese right-angle glass method) in the esotropic group and - 97 ± 29 prism diopters in the exotropic group. In the whole study population and taken separately in the esotropic group and exotropic group, the disc ovality index (defined as ratio of minimal-to-maximal optic disc diameter) did not differ significantly between the deviating eyes and the contralateral fixating eyes (all P > 0.05). As a corollary, the disc ovality index and the prevalence of parapapillary beta/gamma zone did not differ significantly between the esotropic group and the exotropic group (all P > 0.05). CONCLUSIONS: Optic disc ovality did not differ markedly among long-lasting esotropic eyes, exotropic eyes, and non-strabismic eyes. It suggests that optic disc shape may not be markedly influenced in non-highly myopic eyes by a potential backward pull of the optic nerve on the optic disc structures in adduction or abduction.

Clinical characteristics and surgical outcomes of acute acquired Comitant Esotropia.

BACKGROUND: To describe the clinical characteristics and the outcomes of strabismus surgery for acute acquired comitant esotropia (AACE). METHODS: Medical records of 45 AACE patients were retrospectively analyzed. The insertion location of medial rectus was compared between the AACE patients and comitant exotropic patients. The location was also compared with those measured in other studies. Surgical outcome measurements included amount of deviation and level of binocularity at last follow-up. RESULTS: The distance from medial rectus to limbus was shorter in AACE patients than in patients with comitant exotropia. The distance was also shorter in AACE patients than patients in other studies. Out of the 45 patients, 2 had neurological diseases. Neostigmine test was negative in all patients. The age at onset of AACE was 5-47 years (mean 19.1 ± 7.3 years), one patient was 5 years (2.2%), 20 patients were 11-17 years (44.5%) and the other 24 patients were 18-47 years old (53.3%). The mean cycloplegic refraction was - 4.1 ± 3.0 diopters (D) and 41 patients were myopic (91%). The angle of deviation was 40.5 ± 19.5 prism diopters (PD) at distance and 35.6 ± 19.9PD at near preoperatively. The angle was 0.8 ± 1.6 PD at distance and 0.7 ± 1.8 PD at near postoperatively. Diplopia resolved in patients who underwent strabismus surgery, with no recurrence during the follow-up period. Thirty patients had stereopsis postoperatively. CONCLUSIONS: AACE seems to occur mostly in older children and adults and myopes. The distance from the insertion to limbus of medial rectus was shorter in patients with AACE. Good results can be achieved by strabismus surgery.

Sudden Diplopia at a Pediatric Emergency Department: A Case of Gradenigo Syndrome in a Child.

OBJECTIVE: Otitis media, facial pain in trigeminal region, and ipsilateral abducens nerve palsy clinically define Gradenigo syndrome, a rare but serious complication of suppurative middle ear infection. Radiological investigation is required to confirm petrous apex involvement and to exclude further consequences as sinus thrombosis, meningitis, and intracranial abscess. METHODS/RESULTS: We report the case of an 8-year-old child referred to our emergency department for recurrent headache and sudden strabismus. Clinical evidence of suppurative otitis media raised the suspicion for Gradenigo syndrome, definitively confirmed at computed tomography and magnetic resonance imaging scans. Conservative treatment alone enabled complete clinical and radiological remission, without long-term sequelae. CONCLUSIONS: Despite being a rare condition, Gradenigo syndrome should be taken into account as potential differential diagnosis in children referred to emergency department for recurrent headache and strabismus. An accurate anamnesis to document recent ear infection is mandatory to orientate the diagnosis and focus radiological investigations. Early recognition and timely intervention may allow conservative management to succeed, avoiding the need for surgery and serious sequelae.

Lateral rectus dermoid cyst presenting as incomitant esotropia.

A 24-year-old male presented with decreased vision associated with inward deviation of his left eye since childhood and gradually progressive prominence of left eye for 6 months. Left eye examination revealed visual acuity of 2/60, convergent squint with restricted abduction and medial dystopia. Computed tomography (CT) scan showed a well-circumscribed mass with fat fluid levels temporal to the optic nerve indistinguishable from the left lateral rectus. Intraoperatively, a well-encapsulated mass was identified within the lateral rectus muscle which was confirmed as dermoid cyst on histopathology. Patient subsequently underwent surgical correction of his esotropia and the final cosmetic outcome was satisfactory. Dermoid cysts are common orbital lesions usually found overlying suture lines. A dermoid cyst presenting within the ocular muscles is a rare entity. Deep dermoid cyst should be considered as one of the differentials for focal enlargement of extraocular muscles.

LONG-TERM VARIABILITY OF STRABISMUS ANGLE IN NEUROLOGICALLY IMPAIRED PREMATURE INFANTS: A 12-YEAR FOLLOW UP.

The aim of this retrospective study was to determine the strabismus angle variability and rationality of surgical treatment of strabismus in prematurely born children with neurological impairment during 12-year follow up. Eleven premature infants born in 2003 were included in the study and treated with equal conservative approach from 2005 until 2016. Initial esotropia was found in seven and exotropia in four of eleven children. Changes in the strabismus angle correlated significantly with aging of the children. In children with initial esotropia, the strabismus angle became less convergent (less positive), changed the orientation and became more divergent with aging. In those with initial exotropia, the angle became less divergent (more positive), changed the orientation and became more convergent. Moreover, a significant difference in the strabismus angle was found during the 12-year follow up. Based on our results, due to the variability in strabismus angle, we did not find enough evidence for optimal timing or rationality of strabismus surgery in neurologically impaired children born prematurely.