Clinical characteristics and aetiology of acute acquired comitant esotropia

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

Background

Acute acquired comitant esotropia (AACE) is a rare subtype of esotropia that occurs after infancy. The exact pathogenesis of AACE remains unknown with aetiologies ranging from benign conditions to serious underlying neurological diseases being reported. Given the elusive characteristic of AACE, diagnostic and management guidelines remain unclear. This systematic review aims to contribute to this field by summarising the risk factors for AACE reported thus far.

Methods

A systematic review was conducted with papers found in CINAHL, MEDLINE, Cochrane library, PubMed databases and other sources. Eligible studies investigating the risk factors for, and clinical features of, AACE in children and young adults were critically appraised before relevant data were extracted and discussed via a narrative summary.

Results

Twelve studies were included in the final review, of which six and eight papers reported on benign and non-benign risk factors for AACE respectively. Identified benign risk factors varied among studies, while non-benign risk factors were associated with intracranial pathologies, multiple sclerosis and head trauma.

Conclusion

Given the low generalisability of study findings, no definitive conclusions can be drawn on the significance of each risk factor on AACE development. Further prospective research with more objective measurements of 'near work', larger sample sizes and control groups is required to better ascertain any cause-effect relationship, refine the diagnostic criteria for each AACE subtype and advise on appropriate management guidelines for AACE.

Neurological pathologies associated with acute acquired comitant esotropia

Previously reported cases of acute acquired comitant esotropia (AACE) with unknown etiologies have been reported in both children and adults. However, AACE can be associated with neurological disorders that require neuroimaging probes. The author recommends that clinicians should perform comprehensive neurological assessments to rule out neurological pathologies in AACE, especially in the presence of A or V pattern esotropia, nystagmus, or abnormal ocular and neurological indications (e.g. headache, cerebellar imbalance, weakness, nystagmus, papilloedema, clumsiness, and poor motor coordination).

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.

Efficacy of augmented-dosed surgery versus botulinum toxin A injection for acute acquired concomitant esotropia: a 2-year follow-up

BACKGROUND/AIMS

This study aims to evaluate the clinical efficacy of botulinum toxin type A (BTXA) injection and augmented-dosed surgery in the treatment of acute acquired concomitant esotropia (AACE), and explore potential risk factors associated with recurrence.

METHODS

A total of 104 patients diagnosed with AACE between October 2020 and January 2021 were included and voluntarily chose to undergo augmented surgery or BTXA injection. The follow-up assessments ended in November 2022. Multivariable linear regression analysis was used to identify potential factors that influence the dose-response of bilateral medial rectus recession (MRrec). Kaplan-Meier survival analyses and Cox proportional hazards models were performed to evaluate rate and risk factors for AACE relapse.

RESULTS

A total of 31 AACE patients chose augmented-dosed esotropia surgery, and 73 chose BTXA treatment. During the 2-year follow-up, the surgical group achieved more stable postoperative results with no recurrence of diplopia, while only 68.68% (95% CI 55.31% to 78.79%) patients achieved orthophoria in the BTXA group. For patients undergoing BTXA treatment, hours of near work per day were demonstrated to be a significant risk factor for AACE relapse (HR 1.29, 95% CI 1.00 to 1.67). The dose-response of augmented-dosed bilateral MRrec was positively correlated with preoperative deviation angle (R2=0.833; β=0.043, 95% CI 0.031 to 0.055; p<0.001).

CONCLUSION

Our findings provided quantitative evidence that augmented-dosed surgery would achieve more stable and favourable surgical outcomes for AACE patients compared with BTXA injection. However, BTXA treatment is still proposed for patients with small deviation angles due to its advantages of reduced trauma, operational simplicity, low cost and quick recovery.

Clinical characteristics and treatment outcomes of myopic children and adolescents with acute acquired comitant esotropia

CLINICAL RELEVANCE

Acute acquired comitant esotropia (AACE) is becoming increasingly common in young children. Understanding clinical characteristics and treatment outcomes can inform future practice.

BACKGROUND

To evaluate clinical characteristics of myopic children and adolescents with AACE, and the outcomes of varying treatments.

METHODS

A retrospective review of medical records was conducted to identify patients diagnosed with AACE and diplopia between 2016 and 2020. The duration of smartphone use, angle of deviation, refractive error, stereopsis, and treatment options were analysed. The motor outcomes were evaluated at the earliest 6-month postoperative visit (6-30 months), and orthotropia or esodeviation ≤10 prism dioptres (PD) was defined as success. Successful sensory outcomes were defined as the elimination of diplopia in primary gaze or the presence of stereoacuity.

RESULTS

Twelve patients diagnosed with AACE were identified. Ages were between 9 and 19 years (15.6 ± 3.3 years). All patients showed convergent and comitant esotropia ranging from 12 to 40 PD at distance fixation that was nearly equivalent for distance and near fixation. The mean age at the initial visit was 15.6 ± 3.3 years. Post-treatment esodeviations were significantly lower at both distance and near compared to pretreatment (p < 0.001, for both). Eight patients required surgery and were treated with bilateral medial rectus muscle recession, two patients were treated with botulinum toxin, and two patients were followed with prismatic glasses. Nine of 10 patients (%90) treated with either surgery or botulinum toxin had successful motor and sensory outcomes.

CONCLUSIONS

Surgery is the most efficient treatment option; botulinum toxin and prismatic glasses could be useful treatment options in patients who refuse to have surgery or for whom the amount of deviation is small and variable.

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.

Still an Unsolved Question: The Place of Cranial Magnetic Resonance Imaging in Acute Acquired Concomitant Esotropia

PURPOSE

The aim of this study was to collect further data to estimate the risk of relevant intracranial pathology and thereby better assess the need for cranial imaging in children with acute acquired comitant esotropia (AACE). To date, there is still not enough literature on this topic to enable a consensus on the diagnostic algorithm.

METHODS

We analyzed data from patients with convergent strabismus who received cranial imaging via magnetic resonance imaging (MRI). Twenty-one patients received a cranial MRI for the diagnostic evaluation of AACE. The age range was from 2 to 12 years, and the mean age at the time of diagnosis was 5.5 years. Of these patients, only one exhibited insignificant MRI findings, with no therapeutic consequences.

CONCLUSIONS

Our data add further evidence that AACE without neurological findings or other ophthalmologic anomalies might not be an indication for cranial MRI as a diagnostic screening tool.

Neurological pathologies in acute acquired comitant esotropia

BACKGROUND

Acute acquired comitant esotropia (AACE) is an uncommon subtype of esotropia characterized by sudden and usually late onset of a relatively large angle of comitant esotropia with diplopia in older children and adults.

METHODS

A literature survey regarding neurological pathologies in AACE was conducted using databases (PubMed, MEDLINE, EMBASE, BioMed Central, the Cochrane Library, and Web of Science) in order to collect data for a narrative review of published reports and available literature.

RESULTS

The results of the literature survey were analyzed to provide an overview of the current knowledge of neurological pathologies in AACE. The results revealed that AACE with unclear etiologies can occur in many cases in both children and adults. Functional etiological factors for AACE were found to be due to many reasons, such as functional accommodative spasm, the excessive near work use of mobile phones/smartphones, and other digital screens. In addition, AACE was found to be associated with neurological disorders, such as astrocytoma of the corpus callosum, medulloblastoma, tumors of the brain stem or cerebellum, Arnold-Chiari malformation, cerebellar astrocytoma, Chiari 1 malformation, idiopathic intracranial hypertension, pontine glioma, cerebellar ataxia, thalamic lesions, myasthenia gravis, certain types of seizures, and hydrocephalus.

CONCLUSIONS

Previously reported cases of AACE with unknown etiologies have been reported in both children and adults. However, AACE can be associated with neurological disorders that require neuroimaging probes. The author recommends that clinicians should perform comprehensive neurological assessments to rule out neurological pathologies in AACE, especially in the presence of nystagmus or abnormal ocular and neurological indications (e.g., headache, cerebellar imbalance, weakness, nystagmus, papilloedema, clumsiness, and poor motor coordination).

Botulinum Toxin Injection versus Extraocular Muscle Surgery for Acute Acquired Comitant Esotropia

Purpose

To compare the success rate of extraocular muscle surgery and botulinum toxin injection for treatment in patients with acute acquired comitant esotropia (AACE).

Patients and Methods

This is a retrospective cohort study in which we treated 34 patients of AACE with botulinum toxin compared with 80 patients who had been treated with surgery. The data included angle of deviation in prism diopter (PD) at baseline and one, three, and six months after treatment. The main outcome was the success rate in each treatment group.

Results

In the surgery group, mean esodeviation angles at baseline and one, three, and six months after treatment were 50.8 ± 18.3 PD, 4.9 ± 8.3 PD, 4.6 ± 9.5 PD, and 5.5 ± 10.3 PD, whereas those in the botulinum toxin group were 51.2 ± 14.3 PD, 13.9 ± 17.4 PD, 22.0 ± 19.3, and 31.3 ± 23.8 PD, respectively. There was a statistically significant difference in the deviation angles between the two groups (p < 0.001). The success rate in the surgery group at one, three, and six months was 81%, 84%, and 79%, whereas that in the botulinum toxin group was 50%, 27%, and 27%.

Conclusion

Botulinum toxin injection was not as effective as conventional extraocular muscle surgery in AACE patients. However, the treatment is safe, fast-acting, and improves both cosmetic appearance and quality of life. This may be considered as a chance for patients not preferring surgery.

Acute comitant strabismus in anti-GQ1b antibody syndrome

Ophthalmoplegia is the diagnostic hallmark of anti-GQ1b antibody syndrome. This study aimed to define the patterns of acute comitant strabismus in patients with anti-GQ1b antibody syndromes. We retrospectively analyzed the ocular motor findings in 84 patients with anti-GQ1b antibody-associated ophthalmoplegia during the acute phases. Of the 84 patients, 11 (13%) showed acute comitant strabismus. Compared to those without, patients with acute comitant strabismus frequently showed abnormal ocular motor findings that included gaze-evoked (n = 8), spontaneous (n = 4) and positional nystagmus (n = 4), saccadic hypermetria (n = 3), head-shaking nystagmus (n = 2), pulse-step mismatch (n = 1), and impaired visual cancellation of the vestibulo-ocular reflex (n = 1, p < 0.001). On the contrary, iridoplegia (p = 0.029) and ptosis (p = 0.001) were more commonly observed in patients with paralytic (incomitant) strabismus than in those with acute comitant strabismus. Comitant strabismus can manifest during the acute phase of anti-GQ1b antibody syndromes in association with other central ocular motor abnormalities. These findings implicate that the cerebellum and/or brainstem can be the primary target of the anti-GQ1b antibodies.

Augmented-Dose Unilateral Recession-Resection Procedure in Acute Acquired Comitant Esotropia

PURPOSE

To compare the surgical amount of unilateral medial rectus recession and lateral rectus resection (RR) in patients with acute acquired comitant esotropia (AACE) versus common forms of esotropia and to provide dose-response reference for surgical planning in AACE.

DESIGN

Retrospective study.

PARTICIPANTS

Consecutive patients who underwent unilateral RR for AACE or common forms of esotropia correction from January 2018 to January 2022. Only patients who achieved motor and sensory success with a minimum follow-up of 3 months were analyzed.

METHODS

Group differences in the amount of medial rectus (MR) recession and lateral rectus (LR) resection were analyzed using multivariate regression models. Surgical dose responses in AACE were analyzed using multivariable regression models. Regression models were performed with and without adjustment for clinical confounders. Piecewise analysis was used to detect segmented results.

MAIN OUTCOME MEASURES

Group difference in surgical amount and dose responses of unilateral RR in AACE.

RESULTS

Fifty-four patients with AACE and 98 patients with common forms of esotropia were included. To correct comparable deviations, surgical amount performed was significant larger in AACE patients, with the adjusted group differences of 0.49 mm (95% confidence interval [CI], 0.34-0.65 mm; P < 0.001) in MR recession and 1.68 mm (95% CI, 1.25-2.11 mm; P < 0.001) in LR resection in patients with deviation < 40 prism diopters (Δ) and with a group difference of 1.22 mm (95% CI, 0.76-1.68 mm; P < 0.001) in LR resection in those with deviation ≥ 40 Δ. In AACE patients, in the adjusted model taking into account the intercept, dose responses of MR recession and LR resection in patients with deviation < 30 Δ were 5.11 Δ/mm (95% CI, 0.98-9.23 Δ/mm; P = 0.02) and 2.51 Δ/mm (95% CI, 0.57-4.45 Δ/mm; P = 0.02), respectively, and for those with deviation ≥ 30 Δ, the dose response of additional LR resection was 5.48 Δ/mm (95% CI, 4.56-6.40 Δ/mm; P < 0.001) to correct remaining deviation beyond 30 Δ.

CONCLUSIONS

These findings provide quantitative evidence that augmented-dose unilateral RR should be performed in AACE for favorable surgical outcomes. The new surgical dose calculation proposed provides reference for surgical planning.

FINANCIAL DISCLOSURE(S)

The author(s) have no proprietary or commercial interest in any materials discussed in this article.

A rare presentation of esotropia in high myopia in a young adult: a case report

Esotropia in myopia is an uncommon occurrence. Most common cause of esotropia in high myopic elderly is Heavy Eye Syndrome. An uncommon cause in young adults is Acute Acquired Comitant Esotropia often associated with excessive indulgence in near work. A 21 year old male patient presented with diplopia for one year, more for distance than near and spent more than 8-10 hours for near tasks. Unaided visual acuity in BE was 2/60 and was 6/9 in RE and 6/6 in LE with correction. Prism base cover test revealed 25 BO PD for distance and 20 BO PD for near. Diplopia was seen in all position of gaze. Right Eye Lateral rectus resection 8 mm was done and HPE report revealed features of Lateral rectus Muscle atrophy. It is important to understand the pathogenesis of this entity and consider other possible causes of esotropia in myopia. Key words: Myopia, Esotropia, Comitant, Diplopia.

Clinical features and treatment of near-work-related acquired esotropia

AIM

To investigate the characteristics of near-work-related esotropia and the clinical efficacy of botulinum toxin type A (BTXA) injection therapy on it.

METHODS

A total of 107 patients aged 15-57y with near-work-related esotropia were taken as the BTXA-treated group, and 30 other peers without near-work-related esotropia were included in the control group. All participants were refractive corrected to analyse the clinical characteristics of near-work-related esotropia. All subjects were examined including Worth4 spot examination, stereoscopic vision, strabismus angle, accommodative convergence to accommodation ratio (AC/A), far and near positive and negative convergence, positive and negative fusion range, positive and negative relative accommodation. Clinical efficacy was evaluated at a period of 10mo follow-up.

RESULTS

The distant and near stereopsis were found in 84.9% and 77.5% of patients in the BTXA-treated group, respectively. In the control group, all patients had distant and near stereopsis. The incidence of taking off one's glasses to see close objects was significantly higher in the BTXA-treated group than in the control group (P<0.05). The BTXA-treated group showed a smaller range of in-fusion (9.84±5.72)° than the control group (22.04±8.71)° (P<0.05). The near esotropia angle of the BTXA-treated group (17.08±11.98)^Δ was significantly smaller than the distant esotropia angle (19.07±11.68)^Δ (P<0.05). Ten months after injection, the diplopia and esotropia of most patients underwent improvements after treatment (P<0.05).

CONCLUSION

This study reveals that the accommodation function and the habit of near work without wearing spectacles are associated with near-work-related esotropia, while the length of time for near work and the onset time are independent of near-work-related esotropia. Additionally, BTXA injection therapy plays a vital role in relieving diplopia and restoring eye position.