Что такое арахноидальная или арахноидная киста? Янис Шлезиньш, нейрохирург, Доктор медицинских наук

In most cases, arachnoid cysts are congenital and cause no symptoms because they do not increase intracranial pressure (the cysts are either very small or do not cause symptoms because they themselves do not have increased intracranial pressure). Therefore, the patient may only become aware of the cyst if the brain is being examined for another reason. Since the wall of an arachnoid cyst may contain small blood vessels, in the event of a head injury, these blood vessels can rupture and cause bleeding both within the brain and within the cyst. Therefore, patients with asymptomatic arachnoid cysts are at increased risk of significant intracranial hemorrhage in the event of a head injury. If the hemorrhage is significant, the patient may require urgent/emergency surgery for life-saving indications—removal of the intracranial hemorrhage. In rarer cases, when an arachnoid cyst is large and/or presses on surrounding brain structures, it can cause headaches, nausea, dizziness, seizures, cerebrospinal fluid leakage (hydrocephalus), and specific symptoms depending on the specific parts of the brain the cyst presses on (developmental delay, behavioral changes, inability to control voluntary movements (ataxia), and balance disorders). There are also cases where the cyst causes weakness or paralysis on one side of the body (hemiparesis). In childhood, the high pressure inside the skull caused by the cyst (increased intracranial pressure) can also lead to various cranial anomalies, including an enlarged head (macrocephaly). In addition to hydrocephalus, cysts in the so-called suprasellar region can be associated with visual disturbances and hormonal changes, as the pressure they exert can affect hormonal regulation centers in the brain, which can also include menstrual irregularities, growth rate disturbances, developmental abnormalities, etc.