Hydrocephalus is a state of enlargement of the lumen caused by abnormal retention of large amounts of cerebrospinal fluid in the ventricular system or subarachnoid brain, and the posterior group of symptoms. Hydrocephalus caused by congenital diseases or malformations of the cranial spine is called “congenital hydrocephalus”, while those caused by acquired diseases are called “acquired hydrocephalus”. The pathological change of hydrocephalus is the gradual enlargement of the ventricular system. Under normal conditions, the secretion and absorption of cerebrospinal fluid are in a dynamic balance. In pathological conditions, however, excessive intracranial cerebrospinal fluid accumulates in the ventricular system or in the subarachnoid space. Hydrocephalus is clinically divided into two categories: obstructive hydrocephalus and transmissible hydrocephalus. Obstructive hydrocephalus is seen when the cerebrospinal fluid pathway is obstructed and the ventricular system is enlarged above the obstruction without dilatation of the subarachnoid space. It is mostly seen in congenital malformations, such as malformation of the midbrain aqueduct, which is the main cause of hydrocephalus in infants. At birth, there is often a large skull, followed by progressive abnormal enlargement of the skull, disproportionate head and body, mental retardation, and even spastic paralysis. Secondly, tumors directly block or compress the channels of the ventricular system leading to hydrocephalus. Traffic hydrocephalus is mostly caused by acquired lesions, such as meningitis and subarachnoid hemorrhage blocking the arachnoid granules, causing cerebrospinal fluid absorption dysfunction and dilatation of the ventricular system and subarachnoid space.