What is Chiari malformation?
Chiari malformation is a condition in which brain tissue extends into your spinal canal. It occurs when part of your skull is abnormally small or misshapen, pressing on your brain and forcing it downward.
Doctors categorize Chiari malformation into three types, depending on the anatomy of the brain tissue that is displaced into the spinal canal, and whether developmental abnormalities of the brain or spine are present.
Chiari malformation type I develops as the skull and brain are growing. As a result, signs and symptoms may not occur until late childhood or adulthood. The pediatric forms, Chiari malformation type II and type III, are present at birth (congenital).
How common is Chiari malformation?
In the past, it was estimated that the condition occurs in about one in every 1,000 births. However, the increased use of diagnostic imaging has shown that Chiari malformation may be much more common. Complicating this estimation is the fact that some children who are born with this condition may never develop symptoms or show symptoms only in adolescence or adulthood. Chiari malformations occur more often in women than in men and Type II malformations are more prevalent in certain groups, including people of Celtic descent. Please discuss with your doctor for further information.
What are the symptoms of Chiari malformation?
Headache is the hallmark sign of Chiari malformation, especially after sudden coughing, sneezing, or straining. Other symptoms may vary among individuals and may include:
- Neck pain
- Hearing or balance problems
- Muscle weakness or numbness
- Difficulty swallowing or speaking
- Ringing or buzzing in the ears (tinnitus)
- Curvature of the spine (scoliosis)
- Problems with hand coordination and fine motor skills.
Some individuals with CM may not show any symptoms. Symptoms may change for some individuals, depending on the compression of the tissue and nerves and on the buildup of CSF pressure.
Infants with a Chiari malformation may have difficulty swallowing, irritability when being fed, excessive drooling, a weak cry, gagging or vomiting, arm weakness, a stiff neck, breathing problems, developmental delays, and an inability to gain weight.
There may be some symptoms not listed above. If you have any concerns about a symptom, please consult your doctor.
When should I see my doctor?
If you have any signs or symptoms listed above or have any questions, please consult with your doctor. Everyone’s body acts differently. It is always best to discuss with your doctor what is best for your situation.
What causes Chiari malformation?
Chiari malformation type I occurs when the section of your skull containing a part of your brain (cerebellum) is too small or is deformed, thus putting pressure on and crowding your brain. The lower part, or tonsils, of the cerebellum are displaced into your upper spinal canal.
Chiari malformation type II is nearly always associated with a form of spina bifida called myelomeningocele.
When the cerebellum is pushed into your upper spinal canal, it can interfere with the normal flow of cerebrospinal fluid that protects your brain and spinal cord.
This impaired circulation of cerebrospinal fluid can lead to the blockage of signals transmitted from your brain to your body, or to a buildup of spinal fluid in the brain or spinal cord.
Alternatively, the pressure from the cerebellum upon the spinal cord or lower brainstem can cause neurological signs or symptoms.
What increases my risk for Chiari malformation?
There’s some evidence that Chiari malformation runs in some families. However, research into a possible hereditary component is still in its early phase.
Diagnosis & treatment
The information provided is not a substitute for any medical advice. ALWAYS consult with your doctor for more information.
How is Chiari malformation diagnosed?
To diagnose your condition, your doctor will review your medical history and symptoms and conduct a physical examination.
Your doctor will also order imaging tests to determine the cause of your condition and diagnose your condition. Tests may include:
- Magnetic resonance imaging (MRI). An MRI is often used to diagnose Chiari malformation. An MRI uses powerful radio waves and magnets to create a detailed view of your body. This safe, painless test produces detailed 3-D images of structural abnormalities in your brain that may be contributing to your symptoms. It can also provide images of your cerebellum and determine whether it extends into your spinal canal. An MRI can be repeated over time, and it can be used to monitor the progression of your disorder.
- Computerized tomography (CT) scan. Your doctor may recommend other imaging techniques such as a CT scan. A CT scan uses X-rays to obtain cross-sectional images of your body. A CT scan can help to reveal brain tumors, brain damage, bone and blood vessel abnormalities, and other conditions.
How is Chiari malformation treated?
Treatment for Chiari malformation depends on the severity and the characteristics of your condition.
If you have no symptoms, your doctor likely will recommend no treatment other than monitoring with regular examinations and MRIs.
When headaches or other types of pain are the primary symptom, your doctor may recommend pain medication.
Reducing pressure by surgery
Doctors usually treat symptomatic Chiari malformation with surgery. The goal is to stop the progression of changes in the anatomy of your brain and spinal canal, as well as ease or stabilize your symptoms.
When successful, surgery can reduce pressure on your cerebellum and spinal cord, and restore the normal flow of spinal fluid.
In the most common surgery for Chiari malformation, called posterior fossa decompression, your surgeon removes a small section of bone in the back of your skull, relieving pressure by giving your brain more room.
In many cases, the covering of your brain, called the dura mater, may be opened. Also, a patch may be sewn in place to enlarge the covering and provide more room for your brain. This patch may be an artificial material, or it could be tissue harvested from another part of your body.
Your doctor may also remove a small portion of the spinal column to relieve pressure on your spinal cord and allow more space for the spinal cord.
The surgical technique may vary, depending on whether a fluid-filled cavity (syrinx) is present, or if you have fluid in your brain (hydrocephalus). If you have a syrinx or hydrocephalus, you may need a tube (shunt) to drain the excess fluid.
Surgical risks and follow-up
Surgery involves risks, including the possibility of infection, fluid in your brain, cerebrospinal fluid leakage or problems with wound healing. Discuss the pros and cons with your doctor when deciding whether surgery is the most appropriate alternative for you.
The surgery reduces symptoms in most people, but if nerve injury in the spinal canal has already occurred, this procedure won’t reverse the damage.
After the surgery, you’ll need regular follow-up examinations with your doctor, including periodic imaging tests to assess the outcome of surgery and the flow of cerebrospinal fluid.
Lifestyle changes & home remedies
What are some lifestyle changes or home remedies that can help me manage Chiari malformation?
The following lifestyles and home remedies might help you cope with Chiari malformation:
Please discuss with your doctor for further information.
If you have any questions, please consult with your doctor to better understand the best solution for you.
Hello Health Group does not provide medical advice, diagnosis or treatment.
Chiari malformation. https://www.ninds.nih.gov/Disorders/Patient-Caregiver-Education/Fact-Sheets/Chiari-Malformation-Fact-Sheet#8. Accessed July 18, 2017.
Chiari malformation. http://www.mayoclinic.org/diseases-conditions/chiari-malformation/home/ovc-20249651. Accessed July 18, 2017.
Review Date: July 20, 2017 | Last Modified: September 13, 2019