Chiari Malformations

For rare disorders such as Chiari malformations, a clear treatment path isn’t always obvious. UT Southwestern Medical Center’s team of interdisciplinary experts work together and explore every angle to determine the best course of action to restore and maintain a patient’s quality of life.

World-Class Care for Rare Conditions

In a Chiari malformation, brain tissue extends into the spinal cord and interferes with the circulation of cerebrospinal fluid. This problem can occur when the cavity near the base of the skull is abnormally small, so the lower part of the brain (cerebellum) gets pushed downward.

The three main categories of Chiari malformations are:

• Type I, the most common, is usually congenital (present at birth), though acquired cases are possible. It might not cause any symptoms, and the defect generally isn’t obvious at birth – often going unrecognized until adolescence or adulthood.
  
• Type II is more severe and is usually noticed during childhood.
  
• Type III is extremely rare and is apparent during infancy.
  

Many institutions refer these cases to UT Southwestern because we offer a team of Chiari malformation specialists who review each patient’s condition from a host of perspectives. Our neurologists, neurosurgeons, neuroradiologists, and others work together and with patients to come up with the best treatment strategy for each specific situation.

Symptoms of Chiari Malformations

Many people with the most common type of Chiari malformation don’t experience symptoms, and the malformation is discovered incidentally. If symptoms do occur, severe headache and neck pain are the most common. Other symptoms of Chiari malformations can include:

• Dizziness
  
• Vertigo
  
• Disequilibrium
  
• Visual disturbances
  
• Ringing in the ears
  
• Difficulty swallowing
  
• Palpitations
  
• Sleep apnea
  
• Muscle weakness
  
• Impaired fine motor skills
  
• Chronic fatigue
  
• Painful tingling of the hands and feet 
  

People with Chiari malformations often also have hydrocephalus (increased brain fluid), syringomyelia (cyst of the spinal cord), and tethered cord syndrome.

Evaluation

Because of the complex range of symptoms, Chiari malformations can be difficult to diagnose. At UT Southwestern, we evaluate a patient’s previous imaging studies and conduct additional imaging studies when needed. We then match what we see to a patient’s specific symptoms to determine the severity of the Chiari malformation.

Treatment for Chiari Malformations

Once we’ve evaluated a patient and made a diagnosis, treatment might include observation with surveillance imaging over time (if a patient is not experiencing symptoms) or surgery if the Chiari malformation is causing symptoms. 

For most patients, monitoring the condition is all that’s required. However, if the Chiari malformation poses a significant threat to a patient’s health, or if symptoms interfere with quality of life, we offer comprehensive perspectives and treatment options. 

When surgery is needed to treat a Chiari malformation, the goal is to stop progressive displacement of brain tissue into the spinal canal, to restore the normal flow of cerebrospinal fluid, and ease or stabilize symptoms.

Surgical options include:

• Foramen magnum decompression: The most common operation to treat a Chiari malformation involves the removal of a small piece of the skull to relieve pressure on the spinal cord. If further decompression is necessary, the surgeon opens the dura – the tissue that covers and protects the brain and spinal cord – to further reduce the pressure, then sews a patch over the new dural opening, allowing even more room for cerebrospinal fluid circulation.
  
• Laminectomy: In this procedure, the surgeon removes a portion of the first cervical vertebrae (the lamina) to make more room for the cerebellum.
  
• Shunt: In some cases, patients might need a shunt to drain excessive cerebrospinal fluid away from the skull and brain to another part of the body where it can be absorbed. Shunts are sometimes implanted before decompression surgery to relieve pressure and improve symptoms. Sometimes, implanting the shunt allows the patient to avoid surgery altogether.

After surgery, patients recover in our dedicated neurointensive care unit (neuro ICU). Neurorehabilitation services are also available in the same building.