Chiari malformation, popularly known as cerebellum prolapse; It is a congenital disease caused by the displacement of parts of the cerebellum, called tonsils, towards the spinal canal. Although it is thought to be a rare disease because very few of them give symptoms or are detected incidentally, it is actually a very common pathological condition in the society. Chiari malformation has several subtypes with varying severity of symptoms and clinical manifestations in the patient. The extent of the sagging in the cerebellum is decided by the neurosurgeon, according to the clinical and radiological evaluations, whether a follow-up or surgical procedure is required.
Chiari malformation is classified into 5 subtypes according to overhanging structures. Type 1 and type 2 make up more than 90% of cerebellum prolapses. Type 1 is the type in which only the tonsillar portion of the cerebellum hangs 5 mm or more downward from the foramen magnum. Almost all of Type 2 is seen with spinal cord development anomalies and hydrocephalus. In this patient group, besides the vermis of the cerebellum, the brainstem and the 4th ventricle also slipped down the foramen magnum. Type 3 is the least common and most severe variety. It is also very difficult to treat. In this, the cerebellum and brain stem are contained in a sac formed at the back of the head. In type 0, there is actually no cerebellum prolapse. It can be described as the fact that patients with fluid accumulation in the spinal cord and related complaints benefit from normal chiari surgeries. Type 1.5, on the other hand, is the type so named because of its similarity to both type 1 and type 2, in which the cerebellar tonsil also protrudes and the brain stem is enlarged in the 4th ventricle.
In type 1, which is the most common type of Chiari malformation, the most common complaint is pain especially in the back of the head and neck, which is exacerbated by laughing, coughing, sneezing and straining, which causes an increase in internal pressure. The most common complaints of cerebellum prolapse are pain in the head, neck, neck and shoulders, especially after intermittent increased intracranial pressure. Headache, especially at night, is such that it wakes you from sleep. Headache is usually accompanied by nausea and sometimes vomiting. The headache is followed by pain and stiffness in the nape, sometimes radiating to the shoulders. Due to the intermittent course of the cerebrospinal fluid circulation, the pain occurs from time to time, sometimes not at all. In addition, shoulder, waist or leg pains are seen, these pains are not reflected. Pain and pressure or pressure in the neck, shoulders and arms are the most common complaints.
While prolapse of the cerebellum does not give many findings in childhood, it gives various findings in adulthood due to the cyst that develops in the spinal cord. When the cerebellum is affected, complaints such as balance disorder, dizziness, nausea and vomiting may occur. If the brain stem is affected in advanced stages; difficulty in swallowing and respiratory arrest during sleep may occur.
The size of the sagging should be 10 mm or more in order to be able to perform surgery on the person suffering from Chiari disease. Patients who are not considered for surgery are followed up first for 6 months and then once a year by taking neck impressions. There is no effective treatment for Chiari malformation other than surgery yet. The selection of patients to be treated only in type 1 can sometimes be quite difficult. Because most of the patients have only neck and headache complaints and it is not always easy to associate this with cerebellum prolapse. In addition, even though it is associated with cerebellum prolapse, the fact that headache affects the quality of life is very important for the surgical decision. MRI control is recommended for patients with normal neurological examination and mild to moderate headache complaints. Surgery is very important in the early period in cases where a defect is detected in the neurological examination, especially in cases where the respiratory and cranial nerves are affected. Another important factor in making the surgical decision is fluid accumulation in the spinal cord. While some surgeons advocate that all patients with spinal fluid accumulation should be operated, regardless of the size and level of the accumulated fluid, the general decision is to closely follow-up patients with small spinal fluid accumulation and without any serious symptoms, and to recommend surgery in case of neurological deterioration. One of the basic principles in patients with prolapse of the cerebellum is to evaluate the patient in terms of hydrocephalus, to treat hydrocephalus first if hydrocephalus is present, and to perform surgery if the signs of prolapse of the cerebellum continue in the follow-ups.
