Review articleTonsillar ectopia and headaches
Section snippets
Radiographic and clinical correlations
More than a century after his initial research and publications, Chiari's classification scheme remains widely accepted. The neuroradiologic advance of MRI enables detection of Chiari malformations without the need for invasive procedures (Fig. 1). With routine use of this imaging modality, incidental cerebellar ectopia is observed in subjects who have varying and often poorly localizing symptoms, prompting numerous investigations dedicated to offering radiographic determination of these
Pathophysiology of tonsillar ectopia and headache
Chiari observed hindbrain deformities in patients who had hydrocephalus and considered these anomalies a result of congenital or chronic hydrocephalus, specifically not “acquired” or of late onset [4]. He questioned, however, if chronic hydrocephalus was sufficient to underlie elongation and the conical conformation of the tonsils as characterized in the type I anomaly. In Chiari's subsequent publication on the topic [2], he postulated an alternative mechanism of deficient bone growth with poor
Therapeutic considerations
As discussed previously, patients who have tonsillar ectopia may present with several headache types, including the common occipital headache, migraine, or tension type. Medications, such as nonsteroidal drugs, triptans, tricyclic antidepressants, acetazolamide, COX-2 inhibitors, butalbital, and opioids, are used in these patients with fair results [25]. Those who fail oral medications are sometimes referred for intramuscular injections of corticosteroids and local anesthetic agents in the
Summary
Tonsillar ectopia, encompassing slight descent of the cerebellar tonsils and Chiari I malformations, are disorders observed routinely in older children and adults and are believed to be an acquired form of the Chiari malformations. This entity is different from the other Chiari malformations in that hydrocephalus plays no role in its evolution. More likely it is a disorder of para-axial mesoderm, characterized by posterior fossa hypoplasia and content overcrowding, and not an embryologic
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Pituitary Adenoma Concomitant with Chiari I Malformation: Case Report and Literature Review
2019, World NeurosurgeryCitation Excerpt :The only exceptions to this rule are the prolactinomas, for which medical management with dopamine agonists is the first line of treatment. By contrast, CIM is an uncommon finding, seen in around 0.56% to 3% of the general population,17,18 with an incidence of 3.3 to 8.2 per 100,000 individuals.19 It may produce medullar or upper cervical cord dysfunction during childhood and early adulthood, although some patients become symptomatic only until the fourth or fifth decade of life.4
Chiropractic Care for Headaches and Dizziness of a 34-Year-Old Woman Previously Diagnosed With Arnold-Chiari Malformation Type 1
2014, Journal of Chiropractic MedicineCitation Excerpt :A diagnosis of ACM type 1 is often suspected following physical examination and history. Patients often complain of headaches in the posterior-occipital area, radiating to the eyes with a pressure-type pain made worse with coughing, sneezing, or yelling.1,10 Confirmation of ACM can only be made with imaging, most often made by cervical magnetic resonance imaging (MRI), which is the criterion standard; however, this is also seen on brain MRI, computed tomography, and cervical computed tomography.8
Chiari Type I Malformation in a Pediatric Population
2009, Pediatric NeurologyCitation Excerpt :This measurement is to some degree arbitrary, and does not include other anatomic factors that may determine if a patient develops symptoms or not. Whether individuals with 2-4 mm of tonsillar ectopia may also exhibit Chiari symptoms that respond to surgical intervention remains a matter of debate [17]. With the increasing availability of diagnostic magnetic resonance imaging, more asymptomatic patients are being identified [4,5,18].
Diagnostic Testing for Migraine and Other Primary Headaches
2009, Neurologic ClinicsCitation Excerpt :Chiari I malformation typically is a congenital malformation of cerebellar tonsillar herniation at least 5 cm below the foramen magnum. The headache attributed to Chiari I malformation is occipital or nuchal-occipital with occasional radiation unilaterally to frontotemporal or shoulder regions and sometimes generalized.38 The pain may be dull, aching, or throbbing and may last less than 5 minutes to several hours to days.
Intracranial incidental findings on brain MR images in a pediatric neurology practice: A retrospective study
2008, Journal of the Neurological Sciences