Choroid plexus papillomas are slow-growing benign tumors that originate from the epithelial cells of the choroid plexus in the ventricles and are more common in children, often accompanied by hydrocephalus. The incidence of this disease is low, accounting for 0.4%-0.6% of all intracranial tumors and 1.7%-2.0% of neuroepithelial tumors, as reported in foreign literature. The incidence of this disease can occur at any age, but it is more common in children, mainly before the age of 10, and accounts for about 3% of intracranial tumors in children. The literature reports that children under the age of 10 years account for 48% of all choroid plexus papillomas, of which about 20% occur in infants under the age of 1 year. The prevalence of this disease is more common in males than females, with a male to female ratio of 1.6:1. The prevalence of this disease varies with age, but in children it is more common in the lateral ventricles and in adults it is more common in the fourth ventricle, with tumors in the lateral ventricles located in the triangular area and also in the temporal horn, frontal horn, or body. In addition to the posterior cranial recess, choroid plexus papilloma can be seen in the lateral crypt of the fourth ventricle or inside or outside the fourth ventricle, and also in the cerebellar horn of the pontine brain, where the tumor originates in the lateral crypt of the fourth ventricle or the fourth ventricle and protrudes to the cerebellar horn of the pontine brain through the lateral foramen. The latter tumor originates in the lateral sulcus of the fourth ventricle or the fourth ventricle and protrudes into the pontocerebellar horn through the lateral foramen. Tumors occasionally occur on the convex side of the brain due to the ectopic development of embryonic remnants of choroid plexus tissue. Pathology The tumor originates from the ventricular choroid plexus tissue. Therefore, most of them occur in the ventricles of the brain and are generally small in size, pink in color, nodular in growth, and clearly demarcated from the brain tissue surrounding the tumor. The surface of the tumor is small and papillary or granular, which is also called mulberry-shaped. The surface of the tumor is rough and the tissues are easy to fall off, the texture is brittle, cystic changes and hemorrhagic necrosis rarely occur, and small calcified particles can be seen. Clinical manifestations The duration of the disease varies, with an average of about one and a half years. There are two main types of manifestations: increased intracranial pressure and limited neurological damage. The causes include obstructive hydrocephalus caused by direct obstruction of cerebrospinal fluid circulation from the location of brain tumor and traffic hydrocephalus caused by disorder of cerebrospinal fluid production and absorption. The intracranial pressure increase in infants and children is directly related to the occurrence of hydrocephalus. In infants and children, increased intracranial pressure is manifested by an enlarged head and increased anterior chimney tone, indifference, lethargy, or irritability. In older children and adults, it may manifest as headache, vomiting and optic nerve papillary edema, and even paroxysmal coma. 2.Limited neurological damage The manifestation of limited neurological damage varies according to the location of the tumor. If the tumor grows in the lateral ventricle, half of them have mild contralateral cone bundle sign; if it is located in the posterior part of the third ventricle, it shows difficulty in upward vision of both eyes; if it is located in the posterior cranial sulcus, it shows unstable walking, nystagmus and ataxic movement disorder. Individuals located in the lateral ventricles may present with head masses. A history of spontaneous subarachnoid hemorrhage is seen in this disease. Most of the tumors are located in the ventricles, and some of them are mobile, so some patients show a sudden increase in cephalic epilepsy and relief. A few of them have forced head position, which may be caused by sudden obstruction of cerebrospinal fluid circulation pathway after tumor movement. CT examination: the tumor is high-density in CT scan, and the enhancement scan is uniform. The sides are clear and irregular, and pathological calcification can be seen. The tumor is mostly unilateral or bilateral, and the triangular area is mostly located in the lateral ventricle, while those located in the posterior cranial recess are mostly accompanied by supratentorial hydrocephalus. Except for choroid plexus papillary carcinoma, tumors are mostly confined to intracerebroventricular area without obvious midline structural displacement. 2.MRI examination: MRI of tumor shows low signal in Tl-weighted image, lower signal than brain parenchyma but higher signal than cerebrospinal report; high signal in T and 2-weighted image, clearly demarcated with cerebrospinal fluid and irregular outline of swelling, some of which can be seen as calcification. The tumor has significant contrast enhancement and hydrocephalus. Treatment and prognosis The treatment of choroid plexus papilloma is surgical resection, and total resection should be achieved if possible. For those occurring in the fourth ventricle, a craniotomy should be performed in the posterior cranial recess, and for those protruding to the cerebellar angle of the pontine brain, a lateral postauricular hook incision can be made, and a single bone window in the Shen should be performed. If the tumor is too large, it is not necessary to make a complete resection to prevent damage to the deep structures, and pay attention to block the tumor supplying artery before resection to reduce bleeding during surgery. For those who cannot completely remove the tumor but can relieve hydrocephalus, bypass surgery should be performed. In case of choroid plexus papilloma, postoperative radiation therapy should be given. With the advancement of microscopic neurosurgical techniques, the operative mortality rate can be controlled to less than 1%; and patients with total resection of tumor can often obtain very satisfactory long-term results.