Chiari Malformations

Chiari malformations are a group of neurological disorders that affect the brain and spinal cord and are characterized by the displacement of the cerebellar tonsils, located at the brain’s base, through the opening at the bottom of the skull. There are three types of Chiari malformations, with type I and type II being the most common. 

Chiari Type I Malformation Causes, Symptoms and Malformation

Chiari type I malformation is the most common type. It is characterized by the downward displacement of the cerebellar tonsils through the foramen magnum, the opening at the base of the skull. This displacement can cause compression of the brainstem and spinal cord, leading to various symptoms. The exact cause of Chiari type I malformation is unknown. However, it is believed to be a congenital genetic condition. The symptoms of Chiari type I malformation can vary from not experiencing symptoms to severe symptoms. The most common symptoms of Chiari type I malformation include headaches, especially at the back of the head, neck pain, dizziness, balance problems, numbness or tingling in the hands and feet, weakness in the arms and legs, difficulty swallowing, ringing in the ears, vision problems, and sleep apnea.

Chiari Type I Malformation Causes, Symptoms and Malformation

Chiari type II malformation is a more severe form of Chiari malformation. It is characterized by the downward displacement of the cerebellar tonsils and the brainstem through the foramen magnum. This displacement can cause spinal cord and brainstem compression, leading to various symptoms. Chiari type II malformation is also a congenital condition often associated with spina bifida, a congenital disability that affects the development of the spinal cord and its protective covering. The symptoms of Chiari type II malformation can be severe and can include difficulty breathing, weakness in the arms and legs, loss of sensation in the arms and legs, difficulty swallowing, vision problems, developmental delays, and hydrocephalus.

Physical Examination, Imaging and Neurological Tests

Chiari type I and II malformations are usually diagnosed through physical examination, imaging, and neurological tests. The physical examination may include tests to check for muscle weakness, reflexes, and sensations. Imaging tests, such as MRI or CT scans, can help to visualize the brain and spinal cord and determine the extent of the malformation. Neurological tests, such as an EEG or EMG, can help evaluate the nervous system’s function.

Treatment of Chiari Malformations

The treatment of Chiari type I and II malformations depends on the severity of the symptoms. Sometimes, no treatment may be necessary if the symptoms are mild or nonexistent.  However, if the symptoms are severe, treatment may be required. The most common treatment for Chiari type II malformation is decompression surgery. Surgery aims to relieve pressure on the brainstem and spinal cord by removing a small portion of the skull and/or the upper spinal vertebrae.