Chiari malformation is a structural defect where brain tissue extends from the skull into the spinal canal, putting pressure on the brain and spinal cord and disrupting the flow of cerebrospinal fluid. In most cases, the condition is present at birth, although symptoms may not appear until late childhood or adulthood.Types of Chiari MalformationThere are four primary types, categorized by severity and the involved brain parts.Type I: This is the most common form, where the cerebellum's lower part is pushed into the spinal canal. Many individuals with Type I show no symptoms and are diagnosed incidentally through imaging for other issues.Type II (Arnold-Chiari malformation): This type is almost always linked to spina bifida and involves both the cerebellum and brainstem extending into the spinal canal. Symptoms often appear in infancy and can be severe.Type III: This is a rare and severe type where parts of the cerebellum and brainstem protrude through an abnormal opening at the back of the skull. This form is often life-threatening and causes severe disabilities.Type IV: This is an extremely rare and severe type where the cerebellum is underdeveloped or missing parts. It is usually fatal in infancy.SymptomsSymptoms can vary widely and may not appear until adulthood in Type I malformations.Common symptoms:Headaches, particularly at the back of the head or neck, which can worsen with coughing, sneezing, or straining.Neck pain.Balance and coordination issues.Poor hand coordination and numbness or tingling in the hands and feet.Dizziness or vertigo.Difficulty swallowing, gagging, or hoarseness.Blurred or double vision, as well as rapid eye movements.Sleep apnea or breathing problems.Infant-specific symptoms (often associated with Type II):Weak cry.Feeding difficulties and developmental delays.Stiff neck or arm weakness.Causes and Risk FactorsMost Chiari malformations are congenital, meaning they develop before birth because the skull is too small or misshapen for the developing brain.Congenital causes:May involve genetic factors, as the condition can sometimes run in families.Poor nutrition, infections, or exposure to harmful substances during fetal development are also considered potential factors.Type II is strongly linked to spina bifida, a neural tube defect where the spinal canal does not close properly before birth.Acquired causes:In rare cases, a Chiari malformation can develop later in life due to causes such as traumatic injury, infection, or a tumor.DiagnosisDiagnosis typically involves a physical and neurological exam, followed by imaging tests for a detailed view of the brain and spine.Magnetic resonance imaging (MRI): This is the most accurate test and can show the extent to which brain tissue has descended and whether there are associated complications like a syrinx (a fluid-filled cyst) in the spinal cord.Computed tomography (CT) scan: Uses X-rays to create detailed images of the bones in the skull and spine.Prenatal ultrasound: In more severe types, the malformation may be detected before birth via an ultrasound scan.Treatment and OutlookTreatment depends on the type and severity of symptoms. Many people with no symptoms may not require treatment.Medical management:For those with mild symptoms like headaches, doctors may recommend pain medication or physical therapy.Regular monitoring with exams and MRIs is recommended for asymptomatic cases.Surgery:If symptoms are severe or neurological damage is progressing, surgery is typically recommended to relieve pressure and restore cerebrospinal fluid flow.The most common procedure is posterior fossa decompression, which involves removing a small piece of bone from the back of the skull to create more space for the brain.Outlook:Surgery often results in significant symptom relief, although there is no cure for the underlying malformation.If symptoms are mild or well-managed, individuals can expect a normal life expectancy. More severe types can be life-threatening or cause permanent disabilitiesBecome a supporter of this podcast: https://www.spreaker.com/podcast/da-crew-podcast--5763835/support.
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33 min