The Arnold-Chiari anomaly is accompanied by dystopia (violation of location) of structures in the posterior fossa of the skull with their displacement through the large opening of the nape beyond the skull into the spinal canal. There is a shift in the tonsils or part of the cerebellum towards the upper part of the spinal canal.
There are four types of this pathology. An Arnold-Chiari type 1 anomaly is manifested by a displacement of the tonsils of the cerebellum, which is not accompanied by additional anomalies of the brain development. This type appears in people after thirty years. The second type includes violation of the location of part of the structures in the posterior cranial fossa and tonsils of the cerebellum. Most often, this type is detected in children. The third type of anomaly is the violation of the location of almost all structures in the posterior cranial fossa. A manifestation of this type is incompatible with life. The fourth type of anomaly is inherently considered a variant of the underdevelopment of the cerebellum. Modern neurosurgery refers him to Dandy-Walker syndrome.
When the cerebellum is pressed into the upper part of the spinal canal, the normal outflow of cerebrospinal fluid, which protects the spinal cord and brain, is disturbed. Disturbances in the circulation of cerebrospinal fluid can cause a blockade of signals transmitted from the brain to organs or an accumulation of cerebrospinal fluid. The pressure that the cerebellum exerts on the spinal cord can cause syringomyelia.
According to many experts, the Arnold-Chiari anomaly is considered a hereditary disease. However, it should be noted that studies aimed at studying this factor are at an initial stage.
Many patients suffering from this pathology do not have signs or symptoms. Such patients are not prescribed treatment. The detection of the disease occurs only when diagnosing other diseases.
The development of the disease in most cases is accompanied by a headache caused by a cough, physical stress or sneezing, numbness and tingling in the hands, impaired sensitivity to temperatures and, as a result, frequent burns. In addition, the disease is characterized by pain in the occipital or cervical region, periodically descending to the shoulders. Difficulties in maintaining balance (uneven gait) and weakening hand coordination are observed.
Due to the fact that many symptoms of the disease are often associated with other ailments, it is necessary to undergo a full diagnosis.
Diagnostic measures begin with examination and questioning of the patient. If the patient complains of pain in the head, but the cause of their occurrence is not clear to the specialist, an MRI will be prescribed. Diagnosis allows you to accurately identify the presence of the disease.
In some cases, the Arnold-Chiari anomaly becomes a progressive disease, leading to very serious complications. These include hydrocephalus (excess fluid in the brain). This necessitates the use of a flexible tube for pumping cerebrospinal fluid to another area of the body. Complications of the disease include paralysis. It develops due to spinal compression. Syringomyelia also refers to possible complications. It is accompanied by the formation of a cyst or cavity in the spine, which is filled with fluid and disrupts the spinal activity.
For patients who have an Arnold-Chiari anomaly, treatment is prescribed in accordance with the severity of the condition. In cases of absence of symptoms, as a rule, regular observations and examinations are prescribed. If primary symptoms appear, the doctor may prescribe painkillers. However, most often the treatment of the disease is performed surgically.