Tonsillar ectopia

OBJECTIVE: Chiari malformations (CMs) are a group of congenital or acquired disorders characterized by hindbrain overcrowding into an underdeveloped posterior cranial fossa. CM is considered largely sporadic-however, there exists growing evidence of transmissible genetic underpinnings. The purpose of this systematic review of all familial studies of CM was to investigate the existence of an inherited component and provide recommendations to manage and monitor at-risk family members. METHODS: This paper includes the following: 1) a unique case report of dizygotic twins who presented at the Toronto Western Hospital Spinal Cord Clinic with symptomatic CM type 1 (CM-1) and syringomyelia; and 2) a systematic review of familial CM...

The diagnosis of Chiari I malformation is straightforward in patients with typical signs and symptoms of Chiari I malformation and magnetic resonance imaging (MRI) confirming ≥5 mm of cerebellar tonsillar ectopia, with or without a syrinx. However, in many cases, Chiari I malformation is discovered incidentally on MRI to evaluate global headache, cervical radiculopathy, or other conditions. In those cases, the clinician must consider if cerebellar tonsillar ectopia is related to the presenting symptoms...

Chiari type 1 malformation (CIM) is defined as tonsillar ectopia of >5 mm, while syringomyelia (SM) is defined as a cerebrospinal fluid (CSF)-filled cavity larger than 3 mm dissecting the spinal cord. Over the last decades, our understanding of these pathologies has grown; however, many controversies still exist almost in every aspect of CIM and SM, including etiology, indication for treatment, timing of treatment, surgical technique, follow-up regime, and outcome. This chapter provides a comprehensive overview on different aspects of CIM and SM and on the still existing controversies, based on the evidence presently available...

The term Chiari malformation refers to a heterogeneous group of anatomical abnormalities at the craniovertebral junction. Chiari malformation type 1 (CM1) refers to the abnormal protrusion of cerebellar tonsils through the foramen magnum and is by far the commonest type. Its prevalence is estimated approximately 1%; it is more common in women and is associated with syringomyelia in 25-70% of cases. The prevalent pathophysiological theory proposes a morphological mismatch between a small posterior cranial fossa and a normally developed hindbrain that results in ectopia of the tonsils...

BACKGROUND: In the absence of papilledema, the presentation of migraine and idiopathic intracranial hypertension (IIH) is very similar. In this respect, an IIH could be presented as a vestibular migraine. Our main objective in this case report is to demonstrate the similarities between IIH and vestibular migraine. CASES: This is a report of 14 patients who have IIH without papilledema presented as vestibular migraine to the clinic and followed from 2020 to 2022...

Chiari Malformation Type I (CM1) is a neurological condition in which the cerebellar tonsils extend past the foramen magnum. While many studies have reported dizziness symptoms in patients with CM1, the prevalence of peripheral labyrinthine lesions is largely unknown. This study aimed to comprehensively describe the audiovestibular phenotype in a cohort of patients with CM1 expressly referred for dizziness. Twenty-four patients with CM1 and a complaint of dizziness/vertigo were evaluated. Hearing and auditory brainstem tract function were essentially normal...

BACKGROUND: Brain imaging has been utilized as a diagnostic tool in the workup of persistent pediatric dysphagia, yet the indications for imaging and the prevalence of Chiari malformation (CM) have not been established. OBJECTIVE: to evaluate the prevalence of CM anomalies in children who underwent brain magnetic resonance imaging (MRI) for pharyngeal dysphagia and to review the clinical findings in the CM group compared to the non-CM group. METHODS: A retrospective cohort study of children who underwent MRI as part of the workup for the diagnosis of dysphagia in a tertiary care children's hospital between 2010 and 2021...

BACKGROUND: Chiari malformation type 1 (CM-1) diagnosis is based on measurement of the cerebellar tonsils on cranial or cervical spine MRI. However. imaging parameters of cranial and cervical spine MRIs could differ because spine MRIs have greater resolution. METHODS: We conducted a retrospective chart review of 161 patients of a single neurosurgeon for Adult CM-I consultation between February 2006 and March 2019. Patients were selected based on receiving both cranial and cervical spine MRIs within a month of each other to determine tonsillar ectopia length for CM-1...

Intraoperative neuromonitoring (IONM) has been used in neurosurgical procedures to assess patient safety and minimize risk of neurological deficit. However, its use in decompressive surgeries of Chiari malformation type I (CM-I) remains a topic of debate. Here we present the case of a 5-year-old girl who presented with acute right lower extremity monoplegia after accidental self-induced hyperflexion of the neck while playing. Imaging revealed 15 mm of tonsillar ectopia with cervical and upper thoracic spinal cord edema...

PURPOSE: Chiari type 1 deformity (Ch1) is associated with bony deformity of the skull base and herniation of cerebellar tonsils more than 5 mm below the foramen magnum. Magnetic resonance imaging (MRI) is used for diagnosis and surgery is advised for symptomatic children. We present a case series using MRI including cerebrospinal fluid (CSF) flow, in children with Ch1 to demonstrate a variety of outcomes, both surgical and spontaneous: spontaneous resolution, spontaneous worsening, postsurgical improvement, and postsurgical deterioration...

BACKGROUND AND PURPOSE: There are a few studies regarding intracranial findings in neonates with Noonan syndrome (NS); however, there are no quantitative analyses in a pediatric population. The aim of this study was to find characteristic intracranial abnormalities and to quantitatively analyze the posterior fossa and cranium base in children with NS. METHODS: A total of 30 patients (11 females and 19 males, mean age 13.1 ± 4.3 years) were retrospectively identified between July 2017 and June 2022...

Purpose : Once believed a result of pathophysiological correlations, the association between Chiari 1 malformation (CM1) and epilepsy has since been considered as a coincidence, due to missing etiologic or clinical matching points. At present, the problem is being newly debated because of the increasing number of CM1 diagnoses, often among children with seizures. No specific studies on this topic are available yet. The present study aimed at updating the information on this topic by reporting on a series of children specifically enrolled and retrospectively analyzed for this purpose...

AIM: To compare the posterior cranial fossa (PCF) dimensions together with the measurements related to basilar invagination and platybasia of craniovertebral junction anomalies (CVJA) in CVJA (+) and CVJA (-) Chiari malformation Type 1 (CM1) patient groups with each other and with healthy control subjects. MATERIAL AND METHODS: The study group was formed of 43 CM1 and 9 tonsillar ectopia (TE) patients. RESULTS: A decrease was determined in the PCF vertical length (clivus and supraocciput line) and PCF volume and an increase in the transverse length (McRae and Twining line) in the CM1 cases compared to the healthy control group...

Chiari malformation Type 1 (CMI) is traditionally characterized as a descent of the cerebellar tonsils more than 5mm below the foramen magnum. In some patients with CMI, there is aberrant pulsatile movement of the tonsils downward during cardiac systole which can affect cerebrospinal fluid (CSF) flow at the foramen magnum. Here, we present an 18-year-old female patient with CMI who presented with worsening symptoms of her CMI. Magnetic resonance imaging (MRI) at this time indicated an increase in cerebellar tonsil movement and decreased CSF flow at the foramen magnum...

Pentalogy of Cantrell is a rare syndrome of anomalous malformation. In the present case, the syndrome was initially diagnosed as a complete pentad, including a supra-umbilical abdominal wall defect, a sternal defect, pericardial defects, an anterior diaphragmatic defect, and heart malformation. Diagnosis required several imaging modalities, including computed tomography (CT) and magnetic resonance imaging (MRI). In this case report, we present an 8-month-old female patient with a thoracic wall defect with ectopia cordis and a bilateral cleft lip and palate...

INTRODUCTION: Atlantoaxial rotatory fixation (AARF) is a rare condition that occurs most commonly in children. The torticollis caused by AARF usually presents as abnormal posturing of the head and neck, with rotation of the chin to the opposite side. AARF in children could occur due to congenital bony malformation, minor trauma, upper respiratory tract infections (Grisel's syndrome), postoperatively after head and neck (ENT) surgery, and unknown reasons. AARF in the postoperative patient is a rare and poorly understood entity...

OBJECTIVE: There is currently a lack of consensus on the utility of intraoperative neuromonitoring (IONM) for decompression of Chiari type I malformation (CM-I). Commonly used monitoring modalities include somatosensory evoked potentials (SSEPs), motor evoked potentials (MEPs), and brainstem auditory evoked potentials (BAEPs). The purpose of this study was to evaluate the utility of IONM in preventing neurological injury for CM-I decompression. METHODS: The authors conducted a retrospective study of a population of adult patients (ages 17-76 years) diagnosed with CM-I between 2013 and 2021...

PURPOSE: This study investigates the feasibility of ultrafast fluid sensitive techniques for evaluation of pediatric spinal cord syrinx. Rapid imaging could obviate the need for sedation, which is often required for children undergoing lengthier standard spine imaging. METHODS: Children undergoing standard spine imaging for Chiari malformation, suspected Chiari malformation, or syrinx were included. Patients who provided informed consent were imaged with rapid acquisition sagittal and axial T2 HASTE spine sequences in addition to standard spine imaging...

Typically, patients with Chiari I malformations (CM I) do not have other intracranial anatomical variations, especially vascular derailments. Here, we report the findings of a cadaveric specimen found to have CM I and cerebellar tonsils supplied by a single posterior inferior cerebellar artery (PICA) i.e., a bihemispheric PICA. An adult male cadaver was found to have CM I. It was also noted that the left PICA descended inferiorly to the level of C1 and that there was absence of the right PICA. The territory of the right PICA was supplied by the left PICA...

OBJECTIVE: Chiari malformation type 1 (CM-1) and spontaneous intracranial hypotension (SIH) are causes of headache in which cerebellar tonsillar ectopia (TE) may be present. An accurate method for differentiating these conditions on imaging is needed to avoid diagnostic confusion. Here, the authors sought to determine whether objective measurements of midbrain morphology could distinguish CM-1 from SIH on brain MRI. METHODS: This is a retrospective case-control series comparing neuroimaging in consecutive adult subjects with CM-1 and SIH...