What is Arnold Chiari Malformation? Causes, Types, and Its Treatment

The Arnold Chiari Malformation refers to a health condition in which the brain tissue extends into the spinal canal. It takes place when the skull’s part is misshapen or smaller than the typical one.

The Arnold Chiari malformation refers to the cerebellum’s structural defect, which is the part of the brain that controls balance. However, several people with the disease may experience no symptoms, but others may experience the symptoms, including

• Muscle weakness
• Dizziness
• Vision issues
• Numbness
• An issue with balance and coordination
• Headache

Causes of Arnold Chiari Malformation

The Arnold Chiari Malformation is generally caused due to structural defects in the spinal cord and brain. These structural defects grow during fetal development. Because of a maternal diet or genetic mutations, the indented bony space at the skull’s base is abnormally small.

As an outcome, the pressure is placed specifically on the cerebellum. This leads to the blockage in the cerebrospinal fluid’s flow that is generally surrounded around and protects the brain and spinal cord.

Types of Arnold Chiari Malformations

There are four types of Arnold Chiari Malformation. This includes:

Type I

Chiari Malformations is the most common type observed in children where the cerebellum’s lower part extends into an opening at the skull’s base. This opening is known as the foramen magnum. Generally, only the spinal cord passes through this opening.

Symptoms associated with Type I Chiari Malformation

• Severe neck and head pain
• Loss of temperature and pain sensation of upper torso and arms
• An occipital headache
• Loss of muscle strength in arms and hands
• Spasticity
• Dizziness
• Drop attacks
• Balance issues
• Hypersensitivity to bright lights
• Blurred or double vision
• Sleep apnea

Type II

This type of Chiari Malfunction is generally seen in children that are born with the spina bifida. Spina bifida generally refers to the incomplete development of the spinal cord or its protective covering.

It is also known as the classic Chiari malformation, where both the brain stem and cerebellum are extended into the foramen magnum.

Symptoms associated with Chiari II malformation

• Alteration in breathing pattern
• Depressed gag reflex
• Arm strength loss
• Rapid, involuntary, downward eye movements

Type III

Type II is a serious form of the disease that involves the herniation or protrusion of the cerebellum and brain stem through the foramen magnum and into the spinal cord. This generally leads to severe neurological defects. However, it is a rare type.

Type IV

Type IV is a rare type of disease phase that involves an undeveloped or incomplete cerebellum. It is associated with the exposed parts of the spinal cord and skull. In addition to the spina bifida, several other conditions are sometimes associated with the disease. This includes:

• Head’s lower back pain
• Dizziness
• Issues with coordination and balance
• Sleep apnea
• Swallowing Difficulties

However, some of the most common symptoms of the disease are associated with the issues with nerves functioning in the brain stem. This includes

• Vocal cords weakness
• Breathing irregularities
• Swallowing Difficulties
• Serious changes in nerves functioning in the tongue and throat

Chiari Malformations Treatment

If the disease is suspected, a doctor will perform the patient’s physical examination to check the functions controlled by the spinal cord and cerebellum. This includes

• Touch
• Balance
• Sensation
• Reflexes
• Motor skills

And the diagnostic tests may includes

• X-Ray
• MRI (Magnetic Resonance Imaging)
• CT Scan (Computed Tomography Scan)
• Swallowing study
• Sleep Study
• Somatosensory evoked potentials
• Brainstem auditory evoked potentials

The goals of surgery are

• Alleviate the pressure on the spinal cord and brain
• Re-establish the normal fluid circulation around the through the area.

The several types of surgeries include:

• Posterior Fossa Decompression Surgery
  This surgery includes the skull’s bottom’s small portion removal to correct the irregular bony structure. The surgeon may also widen and open the dura, which is the brain and spinal cords firm covering.
• Electrocautery
  This surgery utilizes high-frequency electrical currents in order to shrink the cerebellum’s lower part.
• Spinal Laminectomy
  This surgery includes the removal of part of the arched and bony roof of the spinal canal. This enhances the size of the canal and diminishes the pressure on nerve roots and the spinal cord.

Bottom Line!

If anyone has the signs and symptoms associated with the Chiari Malformation, you gotta see the doctor immediately. As many disease symptoms can also be associated with some other disorders, a thorough medical evaluation is essential.