What Type of Doctor Treats a Chiari Malformation?

Woman holding purple ribbon in support of those with headaches caused by Chiari Malformation

A Chiari malformation is a type of structural defect in the skull that can cause headaches, dizziness, and other problems. Symptoms can vary from patient to patient, and although there are standard types of Chiari malformations, each case is unique. Some Chiari malformations just need to be monitored, while others that cause significant symptoms will require surgery.

Centers for Neurosurgery, Spine & Orthopedics (CNSO) provides comprehensive neurosurgical services for patients throughout northern New Jersey. CNSO’s award-winning neurosurgeons use the latest advancements in medical technology to treat Chiari malformations.

Here, the CNSO medical team explains the different types of Chiari malformations and how this condition is treated.

What Is a Chiari Malformation?

A Chiari malformation is a structural defect in the skull that usually is present at birth. Patients with this condition have an abnormally large foramen at the base of the skull, through which the spine exits the brain. This oversized skull foramen allows a small portion of brain tissue to herniate out of the skull and into the spinal canal.

It is not clear what causes Chiari malformations, but the defect occurs during fetal development. After a baby is born, the brain continues to grow as the skull bones begin to harden in place. This can result in a misalignment between skull and brain size, crowding the area where the brainstem and cerebellum are located. At the bottom of the skull, the normal opening (called the foramen magnum) is just below where the spinal cord exits the brain. A Chiari malformation can allow the part of the brain known as the cerebellar tonsil to push into the foramen magnum thereby also blocking the normal flow of cerebrospinal fluid (CSF). Consequently, the patient experiences frequent or unrelenting headaches.

In mild cases, the patient does not have any symptoms and the findings are incidental. In other cases, symptoms can be moderate to severe and sometimes can become life-threatening. Patients diagnosed with a Chiari malformation need a neurosurgical team to monitor the condition and determine whether an operation is necessary to alleviate the symptoms.

Chiari Malformation Types

There are three main types of Chiari malformations:

Chiari Malformation Type I

This is the most common type of Chiari malformation. A Chiari malformation Type I is classified by the presence of cerebellum tissue in the foramen magnum at the base of the skull. Patients with Type I malformations may not develop symptoms until adulthood, or they may not notice any symptoms at all. Often, this type of malformation is not diagnosed until it is caught on a routine imaging scan for an unrelated issue.

Chiari Malformation Type II

Chiari malformation Type II is present at birth and is also known as an Arnold-Chiari malformation. In this type, both the cerebellar tonsils and the brain stem push down into the upper spinal canal. Infants with the more severe form of spina bifida, myelomeningocele, often have Type II Chiari malformations. Babies born with hydrocephalus, a buildup of fluid in the brain, also can have Type II malformations. Type II sometimes is diagnosed on an ultrasound while a baby is still in utero; in other cases, it is not diagnosed until after birth. This type of Chiari malformation often requires surgery.

Chiari Malformation Type III

This type of Chiari malformation is rare and can be life-threatening. In Type III, there is an abnormal opening in the back of the skull that the cerebellum, brainstem, and membranes can extend into. This causes encephalocele, a type of severe swelling at the back of the skull. Type III Chiari malformations usually are detected during pregnancy or at birth. This type has high mortality rates and can cause serious neurological disabilities.

Additionally, there is a type of defect in which the cerebellum does not develop normally that is sometimes labeled as a Type IV Chiari malformation. Most cases of Type IV malformations are fatal during infancy.

Chiari Malformation Symptoms

Signs and symptoms of Chiari malformations can vary in severity. Common symptoms of a Type I Chiari malformation are:

  • Headaches in the back of the head or neck
  • Scoliosis
  • A fluid-filled cyst on the spinal cord known as a syrinx
  • Muscle weakness or trouble balancing
  • Hydrocephalus
  • Sleep apnea
  • Hoarseness
  • Difficulty swallowing
  • Nausea or dizziness
  • Tinnitus

Children with Type I malformations may not notice any symptoms until adolescence.

Some of the symptoms of Type II Chiari malformations are similar, such as hydrocephalus, difficulty swallowing, and scoliosis. Babies and children with Type II malformations may also exhibit:

  • Eyesight problems
  • Hearing loss
  • Noisy breathing
  • Changes in breathing patterns
  • Weakness in the arms or hands
  • Difficulty walking

How Are Chiari Malformations Diagnosed?

In some cases, a Chiari malformation is detected on a prenatal ultrasound before a baby is born. In other patients, the condition is not recognized until childhood or adolescence. To diagnose a Chiari malformation, a provider will begin with a review of the patient’s symptoms and a physical examination. They may perform tests to check for balance, sensation, memory issues, or cognitive delays. They will also use imaging tests, such as:

  • Magnetic resonance imaging (MRI): This type of imaging test uses radio waves to create detailed, 3D images of the brain. An MRI also can identify a syrinx on the spinal column.
  • Computed tomography (CT): A CT scan uses X-rays to create cross-sectional images. It can be used to evaluate a patient for skull abnormalities and rule out other conditions such as brain tumors.

In some cases, a provider will use a special type of imaging called a cine MRI that assesses the flow of CSF. There is no prenatal test that can definitively diagnose a Chiari malformation in utero.

Chiari Malformation Treatments

Treatment will depend on the type of Chiari malformation a patient has and the severity of their condition. For patients who do not experience symptoms or have very mild symptoms, their provider may simply recommend ongoing monitoring, such as an annual physical examination and regular MRIs.

For patients with more severe symptoms, several surgical procedures can relieve pressure on the cerebellum and ensure the normal flow of CSF. An experienced neurosurgeon performs these. Surgical methods for treating Chiari malformation include:

Posterior Fossa Decompression

This is the most common type of brain surgery for treating Chiari malformation. The goal is to restore the normal anatomy of the brain and spinal canal, as well as minimize associated symptoms. In this procedure, a neurosurgeon removes a small amount of bone from the back of the skull, creating more room for the brain tissue.


The dura mater is a layer of tissue that protects the brain and spinal cord. In a duraplasty, a neurosurgeon will open the membrane and sew in a patch of tissue to enlarge the dura mater. Making the dura bigger relieves some of the pressure on the brain. Tissue can be grafted from other parts of the patient’s body or can be synthetic. This procedure usually is performed in conjunction with posterior fossa decompression.


Some patients with Chiari malformation also need a laminectomy to create sufficient space in the spinal canal. This procedure is another type of decompression surgery. It involves the removal of a small piece of the back portion of the vertebra, known as the lamina, to relieve pressure on the spinal cord. Laminectomy also can help restore the normal flow of CSF.


Electrocauterization uses a thin metal probe with an electric current to heat tissue. For patients with a Chiari malformation, electrocautery can be used to shrink the cerebellar tonsils, which can herniate into the foramen magnum. The procedure causes the cerebellar tonsils to retract but does not damage them.

For patients who have a syrinx or hydrocephalus, surgery may include drainage of excess fluid, as well.

What to Expect During Surgery

If a surgical procedure has been recommended for a patient with a Chiari malformation, they will have several preoperative tests. These can include blood work and MRI imaging within 6 months of the planned surgery. The neurosurgeon and the neurosurgical team will explain the surgical plan and answer any questions they may have.

Chiari malformation corrective surgery is performed under general anesthesia. The procedure lasts several hours. After the procedure is complete, the patient will need to stay in the hospital for a day or two. During this time, they will be monitored as they recover. Most patients can go home within a day or two, but they will refrain from strenuous physical activity for the immediate postoperative time-period. Complete recovery from this type of brain surgery can a month or two. The recovery time will depend on the patient’s age, overall condition, and the type of surgical procedure used. Minimally invasive surgical techniques usually result in a shorter recovery time.

After decompression surgery, some pain and swelling are normal side effects, which typically can be managed with over-the-counter pain medication. The patient or their parents also will receive instructions on how to clear and care for the incision site. Sutures or surgical staples usually can be removed within 10 days. The patient will have several follow-up appointments to assess their recovery and ensure that CSF is flowing normally.

Find Expert Neurosurgery Care in NJ

Patients who have been diagnosed with a Chiari malformation can find a team of experienced, board-certified neurosurgeons at Centers for Neurosurgery, Spine & Orthopedics (CNSO) in northern New Jersey. Providing comprehensive care for a wide range of brain and spine conditions, CNSO has extensive experience monitoring and treating all types of Chiari malformations.

The comprehensive team at CNSO includes neurosurgeons, interventional pain management physicians, physiatrists, rehabilitation specialists, and certified physical therapy staff, all working together to ensure quality care. Patients benefit from personalized treatment plans and can schedule appointments at multiple convenient locations or opt for telemedicine services when appropriate. CNSO also has providers who speak the following languages in addition to English: Korean, Mandarin Chinese, Russian, Serbo-Croatian, and Spanish.

The medical staff at CNSO takes a conservative approach to pain management and treatment, supporting individuals at each step of the patient journey and recommending surgery only when needed. For more information or to request an appointment, contact CNSO today.

Centers for Neurosurgery Spine & Orthopedics