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Neonatal Network : NN Aug 2021Arnold-Chiari malformation (ACM), a defect that involves downward displacement of the hindbrain and herniation of the cerebellar vermis, tonsils, pons, medulla, and...
Arnold-Chiari malformation (ACM), a defect that involves downward displacement of the hindbrain and herniation of the cerebellar vermis, tonsils, pons, medulla, and fourth ventricle through the foramen magnum, is the most complex of the 4 types of Chiari malformations. Unique to the other types of Chiari malformations, approximately 95 percent of infants with ACM also present with an associated myelomeningocele (MMC), the most severe form of spina bifida. Among affected infants, those with symptomatic comorbidities incur a significantly higher morbidity and mortality risk. Prompt identification and diagnosis of ACM, as well as evidence-based postnatal and postsurgical nursing and medical care, is critical. Early surgical intervention can repair an existing MMC and restore proper cerebrospinal fluid circulation, which can dramatically improve patient outcomes and quality of life, and reduce disease and health care burden.
Topics: Arnold-Chiari Malformation; Humans; Hydrocephalus; Infant; Meningomyelocele; Quality of Life
PubMed: 34518383
DOI: 10.1891/11-T-704 -
Journal of Neurosurgery. Pediatrics Sep 2019As with many pathologies, the course of our understanding of the Chiari I malformation (CIM) has developed extensively over time. The early descriptions of the Chiari... (Review)
Review
As with many pathologies, the course of our understanding of the Chiari I malformation (CIM) has developed extensively over time. The early descriptions of the Chiari malformations by Hans Chiari in 1891 opened the door for future classification and research on this topic. However, even over a long timeframe, our understanding of the pathophysiology and, more importantly, treatment, remained in its infancy. As recently as the 1970s, CIM was not discussed in popular neurology textbooks. Syringomyelia is listed as a degenerative disorder with no satisfactory treatment. Radiation therapy was considered an option in treatment, and surgery was thought to play no role. During the last 40 years, equivalent to the duration of a neurosurgical career, our understanding of the pathophysiology and natural history of CIM, coupled with modern MRI, has improved the treatment paradigm for this patient population. More importantly, it has given us evidence confirming that CIM is a disorder responsive to surgical intervention, giving patients once thought to be destined for lifelong disability a comparatively normal life after treatment. The purpose of this article is to offer a review of CIM and its important associated entities. The authors will discuss the evolution in understanding of the Chiari malformation and, importantly, distinguish between symptomatic CIM and asymptomatic tonsillar ectopia, based on imaging and presenting symptomatology. They will discuss techniques for surgical intervention, expected outcomes, and complications after surgery. Proper patient selection for surgery based on appropriate symptomatology is tantamount to achieving good surgical outcomes in this population, separating those who can be helped by surgery from those who are unlikely to improve. While our knowledge of the Chiari malformations continues to improve through the efforts of clinical and basic science researchers, surgeons, and patients, our current understanding of these entities represents a monumental improvement in patient care over a relatively short time period.
Topics: Arnold-Chiari Malformation; Asymptomatic Diseases; Decompression, Surgical; Humans; Magnetic Resonance Imaging; Neurosurgical Procedures; Patient Selection; Syringomyelia
PubMed: 31473667
DOI: 10.3171/2019.5.PEDS18382 -
Archives of Neurology Jun 2003
Topics: Arnold-Chiari Malformation; Austria; Germany; History, 19th Century; History, 20th Century; Humans; Neurology
PubMed: 12810499
DOI: 10.1001/archneur.60.6.898 -
Acta Neurochirurgica Jan 2021
Topics: Arachnoid; Arachnoiditis; Arnold-Chiari Malformation; Humans; Syringomyelia
PubMed: 32948891
DOI: 10.1007/s00701-020-04584-3 -
The Veterinary Clinics of North... Mar 2016Chiari-like malformation is a condition of the craniocervical junction in which there is a mismatch of the structures of the caudal cranial fossa causing the cerebellum... (Review)
Review
Chiari-like malformation is a condition of the craniocervical junction in which there is a mismatch of the structures of the caudal cranial fossa causing the cerebellum to herniate into the foramen magnum. This herniation can lead to fluid buildup in the spinal cord, also known as syringomyelia. Pain is the most common clinical sign followed by scratching. Other neurologic signs noted are facial nerve deficits, seizures, vestibular syndrome, ataxia, menace deficit, proprioceptive deficits, head tremor, temporal muscle atrophy, and multifocal central nervous system signs. MRI is the diagnostic of choice, but computed tomography can also be used.
Topics: Animals; Arnold-Chiari Malformation; Dog Diseases; Dogs; Magnetic Resonance Imaging; Treatment Outcome
PubMed: 26631589
DOI: 10.1016/j.cvsm.2015.10.002 -
Optometry and Vision Science : Official... Mar 1992Arnold-Chiari malformation is a congenital malformation of the skull near the foramen magnum in which the cerebellum and the medulla are caudally displaced. This...
Arnold-Chiari malformation is a congenital malformation of the skull near the foramen magnum in which the cerebellum and the medulla are caudally displaced. This herniation of the brainstem causes down-beat nystagmus and oscillopsia, the most commonly presenting sign and symptom, respectively. Differential diagnoses for the Arnold-Chiari malformation include, but are not limited to, demyelinating disease, tumor, and vascular disorders. Symptoms will generally worsen with time and may even be brought on during exercise or valsalva maneuvers. A correct diagnosis can lead to timely surgical intervention which can improve the quality of eye movements. Treatment generally involves the surgical decompression of the surrounding spinal tissue.
Topics: Adolescent; Arnold-Chiari Malformation; Diagnosis, Differential; Diplopia; Esotropia; Humans; Magnetic Resonance Imaging; Male; Nystagmus, Pathologic; Strabismus; Visual Fields
PubMed: 1565422
DOI: 10.1097/00006324-199203000-00011 -
Neuroimaging Clinics of North America May 2019Headache is a common symptom in patients with Chiari I malformation (CMI), characterized by 5 mm or greater cerebellar tonsillar herniation below foramen magnum.... (Review)
Review
Headache is a common symptom in patients with Chiari I malformation (CMI), characterized by 5 mm or greater cerebellar tonsillar herniation below foramen magnum. Radiologists should be aware of the different types of headaches reported by CMI patients and which headache patterns are distinctive features of the diagnosis. A methodical imaging strategy is required to fully assess a CMI patient to exclude secondary causes of tonsillar herniation such as intracranial hypotension or associated conditions such as syrinx. Both anatomic and physiologic imaging can help determine if headaches are CMI associated, and assist clinicians in therapeutic decision making.
Topics: Arnold-Chiari Malformation; Brain; Headache; Humans; Magnetic Resonance Imaging
PubMed: 30926114
DOI: 10.1016/j.nic.2019.01.005 -
Neurosurgery Clinics of North America Oct 2015
Topics: Adult; Arnold-Chiari Malformation; Child; Decompression, Surgical; Humans; Neuroimaging
PubMed: 26408069
DOI: 10.1016/j.nec.2015.07.002 -
Neurology India Mar 2024
Topics: Humans; Arnold-Chiari Malformation
PubMed: 38817188
DOI: 10.4103/neurol-india.Neurol-India-D-24-00173 -
The Pan African Medical Journal 2023
Topics: Humans; Arnold-Chiari Malformation; Hydrocephalus; Meningomyelocele
PubMed: 37275283
DOI: 10.11604/pamj.2023.44.115.36848