Resolution of acute acquired comitant esotropia after suboccipital decompression for Chiari I malformation

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).

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).

Acute comitant esotropia in a very young child due to combined mechanism: A case report

We report a case of esotropia with high hyperopia in a 3-year-old female child. She was initially treated with hyperopic correction and noted to have residual esotropia, which was diagnosed as partial accommodative esotropia. Later when she presented with headache, she was diagnosed to have an intracranial tumour. To our surprise, after neurosurgical excision of tumour, her non-accommodative component of the esotropia resolved over 1 year implying that the intracranial lesion was an additional causative factor for this acute onset Accommodative esotropia. The child attained Orthophoria with the same hyperopic correction.

Botulinum toxin for the treatment of cyclic esotropia in a child with Chiari type I malformation

We report the case of a 4-year-old boy who presented with cyclic esotropia in the setting of a Chiari type I malformation. He was treated with a single administration of botulinum toxin and remained orthotropic at 7-months. To our knowledge, this is the first reported case of cyclic esotropia with Chiari I malformation successfully treated using botulinum toxin.

Acute presentation of Chiari 1 malformation in children

PURPOSE

To review the literature about the acute presentation of Chiari 1 malformation in children, with a focus on acute cervical cord syndromes with impairment of the cortico-spinal tract. To analyze the possible precipitating factors and the pathophysiology of the acute onset.

METHOD

Illustrative case presentation with literature review.

RESULTS

The literature includes just a few dozens of children with acute presentation of Chiari 1 malformation. The more frequent presentations consist of oropharyngeal dysfunction, cranial nerve impairment, high intracranial pressure, peripheral motor deficit. Acute impairment of cervical long tracts is very rare and we could find only 16 previously reported cases of cervical cord impairment with quadriparesis or hemiparesis.

CONCLUSIONS

Nowadays, a lot of asymptomatic Chiari 1 malformations are frequently observed owing to the wide diffusion of magnetic resonance imaging. This raised the question about the management of these patients. Despite severe and even lethal manifestations being reported in previously asymptomatic patients, the absolute rarity of acute deterioration does not justify prophylactic surgery. The diagnosis of Chiari malformation may be initially difficult in patients with isolated, acute, and unusual presentations but physicians should bear in mind its possibility, because prompt cranio-cervical decompression may be decisive.

Divergence insufficiency alleviated by posterior fossa decompression with duraplasty in a patient with Chiari type 1.5 malformation

The authors present a case of Chiari type 1.5 malformation with the uncommon presenting symptoms of esotropia and diplopia due to divergence insufficiency in a 12-year-old girl. Imaging at initial diagnosis revealed cerebellar herniation with extension of the tonsils to the C2 vertebral body, a retroflexed odontoid, and a small cervical syrinx. The patient was initially treated with an uncomplicated Chiari malformation decompression without dural opening. Repeat imaging revealed an adequate decompression. Three months postoperatively the patient's diplopia recurred and she underwent repeat posterior fossa decompression with dural opening and duraplasty. Following repeat decompression with dural opening and duraplasty, the patient's diplopia had not recurred by the 2-year follow-up.https://thejns.org/doi/abs/10.3171/2018.5.PEDS1886.

Decompensated Esophoria as a Benign Cause of Acquired Esotropia

PURPOSE

To determine informative clinical and magnetic resonance imaging (MRI) characteristics of patients with symptomatic adult acquired, comitant esotropia due to decompensated esophoria.

DESIGN

Retrospective, interventional case series.

METHODS

Setting: Institutional.

STUDY POPULATION

Patients with decompensated esophoria who developed acute acquired comitant esotropia.

OBSERVATION PROCEDURES

Ophthalmic examination, stereopsis, and strabismus measurements at distance and near using prism cover tests in diagnostic gaze positions were performed. Patients underwent high-resolution surface coil MRI of extraocular muscles with target fixation, and MRI of the brain. Strabismus surgery was performed under topical anesthesia with adjustable sutures wherever possible. Paired t testing was used to evaluate postoperative changes with 0.05 considered significant.

MAIN OUTCOME MEASURE

Clinical and MRI characteristics, and surgical outcome of patients with decompensated esophoria.

RESULTS

Eight cases were identified involving subjects of mean age 29 ± 9.4 (range: 20-48) years having gradually progressive intermittent horizontal, binocular diplopia for 10 months to 3 years. Mean preoperative esotropia was 31 ± 12 Δ at distance and 29 ± 12 Δ at near, although this was intermittent in 5 patients who exhibited enhanced fusional divergence. Neurologic evaluation and MRI of brain, orbits, and extraocular muscles were unremarkable in all cases. Orthotropia was successfully restored in all by standard or enhanced doses of bimedial rectus muscle recession surgery, improving mean stereoacuity from 535 to 68 arc seconds, although 5 patients exhibited 2-14 Δ asymptomatic residual esophoria.

CONCLUSION

Decompensated esophoria is a benign clinical entity causing acute, acquired, comitant esotropia treatable with enhanced medial rectus recession.

Acute Acquired Comitant Esotropia in Adults: Is It Neurologic or Not?

Objectives. Acute acquired comitant esotropia (AACE) can be a diagnostic challenge for ophthalmologists and neurologists because of its association with neurological pathologies. Our study describes a series of adult patients with AACE of undetermined etiology. Methods. Data on the clinical findings of patients presented with AACE of undetermined etiology with a minimum follow-up of 1 year were retrieved from the medical records and the results analyzed. Results. A series of 9 esotropia cases (age range: 20-43 years) was reviewed. All patients had full duction and versions, without an A-pattern or V-pattern. All patients had esotropia for distance and near. Neurological evaluation in all cases was normal. Among patients, 3 were treated with prisms, 4 were treated with strabismus surgery, and 1 was treated with botulinum toxin injections; 1 patient declined treatment. In treated patients posttreatment sensory testing indicated restoration of binocularity that remained stable throughout follow-up of 1-9 years. The patient that declined treatment had binocular function with base-out prisms. Conclusion. Acute onset esotropia may be seen without a neurological pathology in adults. Good motor and sensory outcomes can be achieved in these patients with AACE of undetermined etiology via surgical and nonsurgical methods.

Esophoria or esotropia in adulthood: a sign of cerebellar dysfunction?

Convergent strabismus is a common diagnosis in early childhood, when it is mostly considered benign. If it develops later in life, strabismus can, however, be a sign of neurological disease. In these cases the underlying pathophysiological mechanisms are largely unknown. In this retrospective case-control study we analyzed the neuro-ophthalmological examination reports of 400 adult patients who presented at the German Center for Vertigo and Balance Disorders to determine an association between ocular misalignment and cerebellar dysfunction. Patients with cerebellar signs (i.e., cerebellar ataxia and/or cerebellar ocular motor signs) had a 4.49 (95 % CI [1.60; 13.78]) times higher frequency of ocular misalignment and specifically a 13.3 (95 % CI [3.80; 55.73]) times increased frequency of esophoria/esotropia (ESO) during distant gaze than patients without cerebellar dysfunction. ESO when looking into the distance was associated with saccadic smooth pursuit, dysmetria of saccades, and downbeat nystagmus (DBN) (χ (2) test, p < 0.0001 for all associations). Patients with cerebellar dysfunction also showed mildly impaired eye abduction (χ (2) test, left eye and right eye: p < 0.0001), associated with horizontal gaze-evoked nystagmus (χ (2) test, p < 0.0001). The association of ESO and DBN implicates a pathophysiological involvement of the cerebellar flocculus, while the association with dysmetric saccades suggests involvement of the oculomotor vermis. This is compatible with animal studies showing that the pathways of the flocculus/posterior interposed nucleus and vermis/nucleus fastigii are both involved in vergence movements and static binocular alignment. From a clinical point of view, a newly diagnosed esophoria/esotropia only during distant gaze may be a sign of a cerebellar disease.

Chiari malformation type I: related conditions

Chiari malformation type I (CMI) is a morphological diagnosis defined as the inferior displacement of the cerebellum through the foramen magnum. In parallel to this basic definition of CMI, there are diagnoses that co-exist with CMI in selected patients. In addition, there are specific constellations of clinical symptoms and signs reported in the literature that occur non-randomly in patients affected by CMI. There is no established system that categorizes these CMI-related conditions or even defines them as causes or consequences of CMI. Identifying the relationship between CMI and these associated disorders may allow greater understanding of CMI etiology and potentially inform CMI management.

Nonsurgical treatment for esotropia secondary to Arnold-Chiari I malformation: A case report

A 14-year-old girl with diplopia and esotropia secondary to Arnold-Chiari I malformation was surgically treated with Arnold-Chiari I malformation decompression (suboccipital craniectomy), C1 and partial C2 laminectomy, and duraplasty. The residual esotropia was treated with compensatory prisms and vision therapy more than 1 year after Arnold-Chiari malformation surgery. The esotropia was resolved after approximately 3.5 months of treatment. Five years later, the patient continued to maintain fusion without compensatory prism.

Exercise-induced esotropia

The authors evaluated a 34-year-old man with exercise-induced diplopia. The diagnostic testing that led to this conclusion is discussed. To the authors' knowledge, this is a rarely reported condition that warrants discussion.

Double Vision Worth a Double Take

An 18-year-old girl presented with an acute acquired comitant esotropia. Investigation showed a brainstem glioma. Discussion of types of acute acquired comitant esotropia, differential diagnosis and neurologic work-up is given. Review of the literature involving acute acquired comitant esotropia is provided.

La malformation de Chiari de type 1 à l’ère de l’imagerie par résonance magnétique

The Chiari type 1 malformation is common. Unlike the Chiari type 2 and 3 malformations, it may remain latent for a long time, becoming symptomatic only in adulthood. The introduction of MRI has resulted in an increased number of diagnoses of this malformation in pediatric patients. It appears to be related to underdevelopment of the posterior cranial fossa. It must be differentiated from acquired tonsillar herniation, particularly when herniation results from intracranial hypotension; these cases are sometimes reported as acquired Chiari I malformation with spontaneous resolution. Tonsillar ectopia may cause symptoms by its direct effect on any or all of the medulla and the cerebellar and upper spinal cord. The most suggestive of the oculomotor disturbances is oscillopsia with downbeat nystagmus. Dysphonia and dysphagia are common. Potentially serious autonomic disturbances are also frequent: sleep apnea, respiratory failure, syncope and even sudden death. Another risk is syrinx formation, resulting from obstruction of CSF circulation in the cisterna magna. Syringomyelia is detected in 32 to 74% of patients with Chiari I malformation. Treatment is surgical. Posterior fossa decompression is achieved by suboccipital craniectomy combined with laminectomy of the upper cervical segments. Surgical intervention is indicated when the malformation is symptomatic and there is no doubt that it is the cause of the symptoms. When a Chiari I malformation is identified fortuitously on MRI, long-term monitoring is essential. The risk of developing symptoms increases over time. Patients should be advised not to participate in contact sports.

Divergence insufficiency

INTRODUCTION AND PURPOSE

To compare the clinical characteristics of a population of patients with divergence insufficiency in the absence of associated neurologic disease to those patients with divergence insufficiency and an associated neurologic disorder.

PATIENTS AND METHOD

A retrospective review of 251 patients diagnosed with divergence insufficiency and/or divergence paralysis. Clinical features include the age at onset, fusional divergence amplitudes, the size of the esodeviation, treatment offered, and the presence or absence of associated neurologic conditions. Classification into primary and secondary divergence insufficiency solely depended on the absence or presence of neurologic disorders, respectively.

RESULTS

The incidence of neurologic disease associated with divergence insufficiency was 17%. The average age at onset was 62 years for primary and 51 years for secondary divergence insufficiency. Nystagmus was noted in 43% of secondary divergence insufficiency patients and 0.01% of primary divergence insufficiency patients. Both groups exhibited decreased fusional divergence at distance fixation while retaining normal fusional divergence at near.

CONCLUSIONS

The majority of patients were classified as primary divergence insufficiency. Though this form of divergence insufficiency is neurologically benign, it may easily mask a more severe neurologic condition for which the presenting symptom is also diplopia for distance viewing only. These results show the importance of obtaining a detailed history regarding the symptoms, as well as documenting neurologic signs, particularly nystagmus, when investigating divergence insufficiency.

Progressive cerebellar tonsillar herniation with recurrent divergence insufficiency esotropia

The Chiari malformations are characterized by herniation of posterior fossa contents through the foramen magnum. Chiari I malformation is currently defined as ectopia of the cerebellar tonsils more than 5 mm below the foramen magnum. Extension of the cerebellar tonsils up to 3 mm may be found in the normal population. Although Chiari malformations are congenital, symptoms often do not manifest until the third and fourth decades of life, or even later. Patients usually present with headache, lower cranial nerve palsies, downbeat nystagmus, ataxia, or dissociated anesthesia of the trunk and extremities. Definitive diagnosis is made by magnetic resonance imaging (MRI), which shows the compressed tonsils extending through the foramen magnum into the cervical subarachnoid space. One of the rare presenting signs of Chiari I malformations is acquired esotropia with a divergence insufficiency pattern. We report such a case in which the initial neuroimaging showed tonsillar herniation, but of insufficient magnitude to meet diagnostic criteria for Chiari I malformation. When the strabismus recurred after initially successful eye muscle surgery, follow-up scan showed progressive tonsillar herniation.

Evaluation and management of the Chiari malformation type 1 for the primary care pediatrician

Diagnosis and treatment of CMI is undergoing reexamination that includes redefinition of the anatomic Chiari malformation and refinement and redefinition of the clinical syndrome. Children with SMI present with head pain of some kind, a neurologic deficit, or with signs of spinal cord dysfunction from syrinx. Some will present with no clinical syndrome at all. Presence of anatomic Chiari malformation or compelling clinical Chiari syndrome should lead to evaluation by a neurologist or neurosurgeon experienced with the syndromes and their treatment. Treatment options are varied but usually result in resolution of symptoms. When symptoms persist after surgery, management is complex and not uniformly successful, even in the most experienced hands.