Hydrocephalus - Arnold Chiari - allied disorders

Hydrocephalus - Arnold Chiari - Allied Disorders

Hydrocephalus and Arnold-Chiari malformation are neurological conditions that can occur independently or in conjunction with each other. These disorders involve abnormalities in the brain and spinal cord, often leading to significant clinical symptoms and requiring medical intervention.

Hydrocephalus

Hydrocephalus is a condition characterized by an abnormal accumulation of cerebrospinal fluid (CSF) within the ventricles of the brain. This can lead to increased intracranial pressure, which may cause damage to brain tissues and result in a variety of symptoms.

Causes

Hydrocephalus can be congenital or acquired. Congenital hydrocephalus is present at birth and may be caused by genetic factors or developmental disorders such as spina bifida. Acquired hydrocephalus can occur at any age due to factors such as brain tumors, meningitis, or traumatic brain injury.

Symptoms

Symptoms of hydrocephalus vary depending on age and the severity of the condition. In infants, symptoms may include an unusually large head, rapid increase in head size, vomiting, sleepiness, irritability, and seizures. In older children and adults, symptoms may include headache, nausea, balance problems, cognitive difficulties, and urinary incontinence.

Diagnosis

Diagnosis of hydrocephalus typically involves neuroimaging techniques such as MRI or CT scan to visualize the accumulation of CSF. Additional tests may include lumbar puncture or intracranial pressure monitoring.

Treatment

The primary treatment for hydrocephalus is surgical intervention to divert the flow of CSF. This is most commonly achieved through the placement of a shunt system, which drains excess fluid to another part of the body where it can be absorbed. An alternative procedure is endoscopic third ventriculostomy (ETV), which creates an opening in the floor of the third ventricle to allow CSF to bypass the obstruction.

Arnold-Chiari Malformation

Arnold-Chiari malformation, also known as Chiari malformation, is a structural defect in the cerebellum, the part of the brain that controls balance. It involves the downward displacement of the cerebellar tonsils through the foramen magnum, the opening at the base of the skull.

Types

There are several types of Chiari malformations, classified based on the severity and anatomical features:

• Type I: The most common form, often asymptomatic, where the cerebellar tonsils extend into the foramen magnum.
• Type II: Also known as Arnold-Chiari malformation, associated with myelomeningocele, a form of spina bifida.
• Type III: A rare and severe form involving herniation of the cerebellum and brainstem.
• Type IV: Involves an underdeveloped cerebellum.

Symptoms

Symptoms of Chiari malformation can include headaches, neck pain, dizziness, balance problems, muscle weakness, numbness, and difficulty swallowing. In severe cases, it can lead to syringomyelia, a condition where a cyst forms within the spinal cord.

Diagnosis

Diagnosis is typically made using MRI, which can clearly show the extent of cerebellar herniation and any associated spinal cord abnormalities.

Treatment

Treatment may involve surgical decompression to relieve pressure on the brain and spinal cord. This can involve removing a small section of bone at the back of the skull to enlarge the foramen magnum and improve CSF flow.

Allied Disorders

Hydrocephalus and Chiari malformations are often associated with other neurological disorders, including:

• Syringomyelia: A condition where a fluid-filled cyst forms within the spinal cord.
• Spina Bifida: A birth defect where there is incomplete closing of the spine and membranes around the spinal cord.
• Tethered Cord Syndrome: A condition where the spinal cord is abnormally attached within the bony spine.

Also see

• Cerebrospinal fluid
• Neurosurgery
• Spinal cord
• Congenital disorder

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WikiMD neurology

External links

• Comprehensive information from the National Institute of health.
  

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