Definition: Chiari malformation is a brain condition where the cerebellum is displaced downward through the foramen magnum into the upper spinal canal.
Consequences: Can lead to severe problems such as increased pressure on the brainstem and blockage of cerebrospinal fluid flow, potentially causing obstructive hydrocephalus.
Anatomy
Normal Anatomy:
Skull
Cerebellum
Brain Stem
Spinal Cord
Foramen Magnum
Chiari Malformation:
Cerebellar tonsils descend through the foramen magnum.
Types of Chiari Malformation
Type 1:
Most common.
Congenital, usually present at birth.
Characterized by the downward descent of the cerebellar tonsil.
Type 2 (Arnold-Chiari Malformation):
Associated with myelomeningocele, a feature of spina bifida.
Involves downward displacement of cerebellum, brainstem, and fourth ventricle.
Leads to obstructive hydrocephalus.
Types 3 and 4: Less common.
Symptoms
Headaches, often exacerbated by coughing or straining.
Neck pain.
Nausea and vomiting.
Balance and coordination problems.
Dizziness.
Muscle weakness.
Vision and hearing disturbances.
Fine motor skill difficulties.
Difficulty with swallowing or speaking.
Symptoms vary among individuals but some are common.
Diagnosis
MRI: Used to assess the extent of cerebellar tonsil descent or herniation.
Type 2 Features:
Descent of cerebellar tonsils, cerebellum, and brainstem.
Associated with myelomeningocele.
Epidemiology
Affects individuals of all ethnicities.
Greater prevalence in females, potentially due to genetic factors.
Treatment
Management:
Physiotherapy
Pain medications
Surgery for severe cases
Additional Resources
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