A disorder known as Chiari Malformation (kee-AH-ree mal-for-MAY-shun) occurs when brain tissue spreads into the spinal canal. When a portion of your skull is excessively tiny or malformed, it presses on your brain and forces it downward.

Chiari malformation is a rare occurrence, although the growing use of imaging testing has resulted in more diagnosis. Doctors divide Chiari malformation into three categories based on the morphology of the misplaced brain tissue and whether or not developmental abnormalities of the brain or spine are present.

As the skull and brain expand, type I Chiari malformation occurs. As a result, symptoms and indicators may not manifest until late childhood or adulthood.

Types II and III of Chiari malformation are present at birth in children (congenital). The form, intensity, and symptoms of a Chiari malformation all influence the treatment.

Treatment options include ongoing monitoring, medication, and surgery. Treatment isn’t always necessary.

What is the Chiari Malformation (CM)?

A structural anomaly in the interaction between the skull and the brain is known as a Chiari malformation (CM). This indicates that the skull is tiny or malformed, pressing on the brain at the base. It is possible for brain tissue to protrude into the spinal canal as a result of this condition.

The cerebellum is affected by CM. It’s where the spinal cord meets the brain, behind the brain stem. The cerebellum can obstruct the brain’s impulses to your body when it presses into the spinal canal.

Chiari Malformation (CM) of Types and Common Symptoms | Risk Factors
Chiari Malformation (CM) 

Fluid can build up in your brain or spinal cord as a result of this. A number of neurological symptoms might result from the pressure and fluid accumulation. Balance, coordination, vision, and speech are some of the common symptoms.

The anomalies were first recognised and classified by Austrian pathologist Hans Chiari in the 1890s, and CM was named after him. Arnold-Chiari malformation, hindbrain herniation, and tonsillar ectopia are some of the other names for this condition.

Continue reading to discover more about this ailment, including its types, causes, and Symptoms.

What Causes these Chiari Malformation & How may they be Prevented?

There are several reasons for CM. The most common cause is embryonic brain and spinal cord structural abnormalities. This might be caused by genetic alterations or a maternal diet deficient in specific vitamins and minerals. Chiari malformation is sometimes known as primary or congenital.

It can also occur later in life if spinal fluid is drained excessively from the lumbar or thoracic portions of the spine as a result of trauma, illness, or infection. Acquired or secondary Chiari malformation is the term for this condition.

Secondary Chiari malformation is substantially less prevalent than primary Chiari malformation.

Risk Factors

Chiari malformation appears to run in certain families, according to some research. However, investigations exploring a putative genetic component are still in their early stages.


Chiari malformation can grow into a progressive condition with significant consequences in certain persons. In other cases, no symptoms are present, and no treatment is required.

The following are some of the problems that might arise as a result of this condition


Syringomyelia is a disorder in which a hollow or cyst (syrinx) arises inside the spinal column in certain patients with Chiari malformation.

Spina Bifida is a Birth Defect

Chiari malformation can cause spina bifida, a disorder in which your spinal cord or its covering isn’t properly grown. A portion of the spinal cord is exposed, posing a substantial risk of paralysis. Myelomeningocele is a kind of spina bifida that is common in people with Chiari malformation type II.


Hydrocephalus, or a buildup of extra fluid in the brain, may need the insertion of a flexible tube (shunt) to redirect and drain the cerebrospinal fluid to another part of your body.

Tethered Cord Syndrome (TCS)

Your spinal cord joins to your spine in this situation, causing your spinal cord to stretch. This can seriously harm your lower body’s nerves and muscles.



A syrinx, a fluid-filled pocket or cyst in the spinal cord, is related with Chiari malformations. Syringomyelia is a term for this ailment. The cyst swells as it fills with cerebrospinal fluid, pressing on the spinal cord.

Chiari Malformation (CM) of Types and Common Symptoms | Risk Factors
Chiari Malformation (CM) 

Increased pressure from a syrinx can compromise neuromuscular function in certain people with a Chiari malformation, resulting in limb paralysis or walking or breathing issues. A spine syrinx might be visible in some children, but not in others. For a definitive diagnosis in certain cases, an MRI scan may be required.


The existence of a syrinx can also be linked to the development of scoliosis, a lateral (side-to-side) bending of the spine in children younger than 16 whose spines are still developing.


Undiagnosed type 1 Chiari malformations in toddlers, adolescents, and teenagers can cause headaches that are often situated at the back of the head and neck and are exacerbated by physical activity.

Apnea (Sleep Apnea)

Another issue that arises in patients with a Chiari malformation is sleep apnea. This is a significant sleep condition marked by short pauses in breathing while sleeping. A sleep study can establish sleep apnea and allow a doctor to recommend therapy.

Types of Chiari Malformation

Based on the morphology of brain tissue and the presence of developing brain/spine abnormalities, there are four forms of Chiari malformation.

Chiari Malformation (CM) of Types and Common Symptoms | Risk Factors
Chiari Malformation (CM) 

Type I Chiari Malformation (most common)

Patients with type 1 don’t usually show symptoms until late childhood or adulthood since the brain and skull are still maturing. Patients with different kinds of Chiari malformation are frequently identified while still in the womb, at birth, or in their early childhood.

Type II Chiari Malformation

Below the foramen magnum, both the brainstem and the cerebellum are involved. Spina bifida and myelomeningocele, a sac-like hole in the back where the spinal cord is exposed to the air, are commonly connected with this disorder. This is a condition that affects youngsters and is also known as Arnold Chiari malformation.

Type III Chiari Malformation

The most dangerous kind is Type III, which is quite uncommon. The cerebellum and brainstem generate a pouch-like structure that protrudes from the back of the head and neck, holding brain tissue. Chiari III is a condition that causes serious neurological problems.

Type IV Chiari Malformation

This kind of Chiari malformation, which is also exceedingly rare, comprises an incomplete or underdeveloped cerebellum.

In addition to these four kinds of Chiari Malformation (CM), a fifth variant, known as “Borderline” or “Type 0,” has recently been proposed.

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