Arnold-Chiari malformation is a serious disorder of the brain associated with the displacement of cerebellar parts. It could also lead to complications such as hydrocephalus, syringomyelia, etc. This write-up provides information on the characteristic signs and treatment of this medical condition.
A structural malformation in the brain, which leads to the displacement of the cerebellar tonsils and medulla, is known as Arnold-Chiari malformation. Hans Chiari, a pathologist from Austria, first brought to light the information about this ailment. However, it was exactly defined by Dr. Julius Arnold, a colleague of Mr. Chiari. Thus, it was known as the Arnold-Chiari malformation, thereafter. In this disorder, the cerebellar tonsils shift downwards through the foramen magnum. It may also cause hydrocephalus, which is characterized by the accumulation of cerebrospinal fluid (CSF) in the brain cavities. Due to the displacement of these parts of the brain, the balance between the inflow and outflow of blood gets disturbed. It results in the blockage of the CSF.
A person affected by this condition may experience symptoms such as dizziness, vision problems, numbness, and headache. Arnold-Chiari is one of the forms of Chiari malformation, and is known as type II malformation. In this type, the person may get affected by ‘Spina bifida cystica’ or ‘myelomeningocele’. Myelomeningocele is a condition in which the spinal cord remains underdeveloped.
The affected person suffers from headaches. The headache is sometimes confused with migraine. Intense pressure in the back of the head is the main reason for the headache.
Along with the cerebellar displacement, the affected individual might experience the following symptoms.
- Syringomyelia: This is a disorder in which a cavity is formed inside the spinal cord. The cavity, also referred to as a ‘syrinx’, elongates in course of time, damaging the spinal cord. It causes various back problems such as stiffness, pain, and weakness.
- Spinal Curvature: It is the state in which the spinal cord is deformed and deviates from its normal curvature.
- Ehlers-Danlos Syndrome: A type of disorder in the connective tissues, the Ehlers-Danlos syndrome results from a problem in collagen synthesis. Collagen is a protein that is found in connective tissues.
- Marfan Syndrome: This syndrome is characterized by aortic root dilation, dislocation of lenses, and constellation of long limbs. Marfan syndrome is hereditary in nature.
Usually, Magnetic Resonance Imaging (MRI) scans are used in the diagnosis of this ailment. If the displacement of the cerebellar parts is more than 5 mm below its normal position, the person is diagnosed with the malformation. The problem is generally detected by the age of 27, however, some of its characteristics may also be found in prenatal stages.
Surgery is the only treatment to deal with this brain disorder. The type of surgery performed is the ‘decompressed surgery’. The purpose behind surgically operating the patient is to remove the excess spinal fluid. During the operation, the neurosurgeon may have to temporarily separate the first three cervical vertebrae from the patient’s body. The occipital bone is also removed. This action allows the fluid to flow by means of a ‘shunt’, which is a surgical tube made of rubber or plastic that helps in draining body fluids.
The research carried out is mostly about improving the diagnostic techniques. The present methods of checking the dislocation of the cerebellar parts may not be fruitful in some cases. Research pertaining to the diagnostic techniques is carried out with respect to the following areas.
- Velocities of the cerebrospinal fluid
- The geometric parameters of the cranium
- Studying the importance of the spinal canal and cranium in relation to the Arnold-Chiari malformation
- Studying the ‘filum terminale’, which is a filament present in the brain.
The ‘World Arnold-Chiari Malformation Association’ acts as a communication bridge between the patients, doctors, and the scientists carrying out research. The need of the hour, however, is to create awareness about this problem in the medical community.