Arnold Chiari Syndrome

Arnold-Chiari Syndrome is a serious congenital anomaly of the development of the human brain. Its essence lies in the discrepancy between the size of the posterior fossa of the skull and other brain structures located in this area. This leads to omission and subsequent infringement of the tonsils of the cerebellum and brain stem. The frequency of this anomaly is 4-8 cases for every 95-100 thousand people.

Currently, the pathogenesis of this disease is not exactly established. Presumably, there are three pathogenetic factors contributing to the occurrence of this disorder:

1. Congenital, hereditarily conditioned neuropathies;
2. Traumatic injuries of the wedge-occipital and wedge-latticed part of the ramp as a result of birth trauma;
3. Hydrodynamic impact of the CSF on the wall of the canal of the spinal cord located in the center.

In 1891, Arnold Chiari identified four types of anomalies, this classification is still used today.

Arnold-Chiari syndrome of the first type is the lowering of the posterior fossa of the skull and nearby structures into the vertebral canal much lower than the level of the large occipital opening. In the second type of anomaly, there is a caudal dislocation of the medulla oblongata, the lower parts of the worm and the IV ventricle, and hydrocephalus often develops. Syndrome Arnold-Chiari of the third type is very rare, it is characterized by a rough displacement of all brain structures of the posterior cranial fossa. The fourth type is represented by cerebellar hypoplasia. The fourth and third types of anomalies are in most cases incompatible with life.

In 80% of cases Arnold-Chiari syndrome is diagnosed together with syringomyelia, a pathology of the development of the spinal cord, characterized by the development of cysts of the spinal cord, which are formed when the posterior fossa of the skull is lowered and the neck is compressed in the cervical spinal cord. The presence of these cysts leads to the development of progressive myelopathy.

Arnold-Chiari Syndrome: Symptoms

The clinical picture of this disease is characterized by the presence of the following symptoms:

• Pain syndrome in the cervical and occipital areas, which is enhanced by sneezing and coughing;
• Decrease in temperature and pain sensitivity, and also muscular strength of the upper limbs;
• Spasticity of limbs;
• Dizziness, fainting, shakiness, aggravated by turning the head, reducing the severity and quality of vision.

In very neglected cases, short breathing stops (apnea), weakness of the pharyngeal reflex and fast, involuntary eye movements are attached to these symptoms.

In some cases, the Arnold-Chiari anomaly may not have any manifestations and is found absolutely randomly in diagnostic procedures. Diagnosis of this disease is carried out using MR-tomography and computed tomography with a three-dimensional reconstruction of all cervical vertebrae, as well as the occipital bone.

Arnold-Chiari Syndrome: Treatment

The intended treatment depends on the patient's condition and the severity of the disease. With such primary symptoms as headache and other types of pain, the doctor can recommend pain medication and regular check-ups. Some patients reported relief from taking anti-inflammatory drugs that can prevent and even delay surgery.

Most often, doctors prefer to treat anomalies surgically. The aim of the operation is to stop the progression of changes in the structure of the spine and brain and stabilize the symptoms. If the surgical procedure is successfully carried out, the pressure on the spinal cord and the cerebellum is significantly reduced, and the outflow of liquor is restored. There are various techniques for performing surgery, which depend on the presence of hydrocephalus. On average, the duration of the operative intervention is one and a half to two hours, the recovery period takes five to seven days.