Chiari Malformation

Need a Spine Specialist in Orange County? For Next-Generation Spinal Care, Choose Hoag Spine Institute.

Your spine serves as strong, flexible support for your entire skeleton. When it’s healthy, the spine is a marvel. When it’s not, it sure can hurt.

But residents of Orange County with spine problems have a strong ally close by, at Hoag Spine Institute. From congenital issues like Chiari malformation to the nagging back and neck pain that can have a big impact on your mobility and sleep, the Hoag Spine Institute’s comprehensive team of spine surgical and medical experts offer next-generation diagnosis and advanced treatment options that can make a big difference in your care and quality of life.

Read on for what you need to know about Chiari malformations, including different types, common symptoms and key terms. And if you need next-generation help for the spine problems that are holding you back, contact the Hoag Spine Institute today at 949-764-1411 or through our online form.

What is Chiari Malformation?

Chiari malformation is a congenital condition, present at birth, in which the rearmost part of the skull just above the spine (the posterior fossa) develops abnormally, making that part of the skull too small to contain a part of the brain called the cerebellum.

Located at the rear of the brain, the cerebellum is a crucial structure, partly responsible for helping you balance, move, coordinate the various parts of your body and other important functions.

Without enough space inside the skull, a part of the cerebellum known as the cerebellar tonsils can begin to bulge (herniate) down into the cervical spinal canal, which is the space inside the neck where the spinal column runs. That can put pressure on the spinal cord and brainstem, while restricting the normal flow of cerebrospinal fluid. In turn, that can lead to a variety of symptoms and even potentially life-threatening complications.

Though Chiari II, Chiari III and Chiari IV can lead to severe and even fatal medical problems soon after birth, many people with mild Chiari malformation Type I reach adulthood without ever knowing they have the condition. Often, Chiari malformation Type I cases are discovered accidentally after X-rays or other imaging tests of the skull are taken for unrelated conditions.

What are the Different Types of Chiari Malformation?

There are several different types of Chiari malformation, each with unique symptoms:

Chiari Malformation Type I

Many with Chiari malformation Type I have no symptoms and may live their whole lives without knowing they have the condition. For those that do experience a Chiari I malformation with noticeable signs, symptoms often appear in late childhood or early adulthood.

In those who experience signs that cause pain or affect their quality of life, Chiari I malformation can be treated through an operation called posterior fossa decompression. During the decompression surgery, a section of bone is removed from the base of the skull to relieve pressure, providing cerebellum and cerebellar tonsils more room.

The most common symptom of Chiari malformation type I are recurring, severe headaches felt at the base of the skull (occipital headache), with the pain increasing if a person coughs, sneezes or strains. This is due to the momentary added pressure on the cerebellum, cerebellar tonsils and spinal cord.

Patients with a Type I malformation can also experience:

  • Head and neck pain
  • Muscle weakness in the hands and arms
  • Collapsing or feeling unsteady due to muscle weakness
  • Feeling dizzy and unable to balance
  • Blurred vision
  • Hearing issues including hearing loss or ringing in the ears (tinnitus)
  • Sleep apnea, which is a condition in which a person can stop breathing while sleeping
Chiari Malformation Type II

Chiari Malformation Type II cases almost always include myelomeningocele, a form of spina bifida in which the spinal canal doesn’t fully close before a child is born.

Other symptoms of a Chiari malformation type II can include:

  • Hydrocephalus, which is a condition characterized by the buildup of excess cerebrospinal fluid (CSF) in the brain
  • Cardiovascular issues
  • Muscle spasms
  • Decreased sensation of cold and hot
  • Certain gastrointestinal issues, including loss of bowel control
  • Problems with the urinary tract, including loss of bladder control
  • Reduced gag reflex and difficulty swallowing
  • Breathing issues, including stopping breathing without warning
Chiari Malformation Type III

A rare form of Chiari malformation, Chiari malformation Type III features severe bulging of the cerebellum or brainstem into the spinal canal. Children born with Chiari malformation Type III often don’t survive long after birth. Those that do survive usually experience severe, lifelong neurological issues, along with problems like hydrocephalus and other birth defects.

Chiari Malformation Type IV

Chiari Malformation Type IV is a very rare type of the condition. In those born with Chiari Type IV, the cerebellum doesn’t develop as it should, causing structural issues with the brainstem and brain. Most children with a Type IV malformation don’t survive.

What Causes Chiari Malformations?

The vast majority of Chiari malformations are due to congenital birth defects, meaning problems with the way the skull, brain and spinal cord developed before a person was born.

According to the American Association of Neurological Surgeons, Chiari malformations occur in around 1 in every 1,000 births. However, most of these cases produce no noticeable symptoms, and remain undiagnosed a person’s whole life.

How is Chiari Malformation Diagnosed?

Many people with Type 1 Chiari Malformation have no symptoms and are only diagnosed after the issue is discovered during other treatments. Those people who do show symptoms are usually diagnosed by scans which can show the structure of the skull, cerebellum and cerebellar tonsils.

Other types of Chiari malformation are often diagnosed during pregnancy or by tests performed soon after birth.

What Are the Risk Factors for Chiari Malformation?

Though research suggests there may be certain types of Chiari malformation that run in families, there are currently no known risk factors that can predict who might develop the condition in the womb. 

Need Chiari Malformation Treatment? Orange County Trusts Hoag.

At the Hoag Spine Institute, we use advanced diagnostic technologies and treatment techniques to improve outcomes and speed up the recovery process for every patient.

Our multidisciplinary team of fellowship-trained specialists is united in your treatment, focused on alleviating pain, restoring function and improving your quality of life using the most conservative methods possible. That includes our commitment to minimally-invasive spine surgery for less downtime, less pain and reduced risk of infection.

Do you need comprehensive, patient-focused spine care in Orange County? The Hoag Spine Institute offers cutting-edge diagnosis, assessment and treatment for a variety of conditions that can impact the brain and spinal cord, including adult Chiari malformation, low back pain, spinal stenosis, congenital deformities, spinal tumors, scoliosis and more.

From operations that restore normal cerebrospinal fluid flow to pain management strategies for those dealing with chronic pain, at Hoag, you’re in good hands. Contact us today at 949-764-1411 or through our online form for more information or to schedule an appointment.


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