Idiopathic intracranial hypertension IIH is a syndrome in which there are clinical symptoms of increased intracranial pressure such as headache, optic nerve papillary edema or associated visual impairment, but no focal neurological signs, no evidence of occupying lesions or ventricular system obstruction. Some patients with severe symptoms, accompanied by progressive loss of visual acuity, have poor results with medical treatment and require short-term surgical treatment. At present, domestic neurosurgery mostly adopts V-P shunt or subtemporal decompression, but the postoperative complications are many or the partial relief of symptoms after surgery is not ideal. 1. Subjects and methods 1.1 General data 7 male cases, 22 female cases, male: female = 1: 3.1. age 32-54 years old, average 36.4 years old. 1.2 Clinical manifestations: 24 cases of headache, 21 cases of nausea and vomiting, 16 cases of dizziness, 23 cases of visual loss, 12 cases of diplopia, 24 cases of optic nerve papillary edema, 2 cases of abducens nerve palsy; lumbar puncture to determine intracranial pressure was higher than normal, but cerebrospinal fluid laboratory routine and biochemical results were normal; CT or MRI examination of the head showed normal results (except for 2 cases in which empty pterygoid saddle was found). 1.3 Diagnostic criteria There were symptoms and signs of increased intracranial pressure without neurological localization signs (except for abducens nerve palsy); increased CSF pressure, greater than 200 mmH2O (greater than 250 mmH2O in obese people); normal CSF routine and biochemical examination, normal or reduced protein; brain CT or MRI and other imaging examinations were basically normal, some of them were accompanied by empty butterfly saddle. Patients with progressive visual acuity loss and severe or unstable initial symptoms after ineffective regular medical treatment. 1.4 Surgical methods All procedures were performed with the Medtronic PS Medical CSF-Lumbosacral Abdominal Shunt System. Depending on the condition, local or general anesthesia was chosen, and the patient was placed in the right or left lateral position with knees bent. A 1.0-cm skin incision was made at the lumbar 3 and 4 intervertebral space, the lateral rectus abdominis muscle next to the umbilicus, and the highest iliac crest, and a lumbar puncture was performed at the lumbar 3 and 4 skin incisions. The needle core is withdrawn, and the shunt is inserted along the puncture needle into the lumbar pool of the vertebral canal (terminal pool) about 4 to 5 cm, and the puncture needle is withdrawn after seeing the smooth flow of cerebrospinal fluid. A subcutaneous tunnel is made ventral to the lumbar puncture site. The needle was inserted along the abdominal incision, and after a sense of falling, the needle was beveled toward the pelvic side, through which the end shunt was placed in the pelvis, about 25 cm. The shunt was then fixed to the lumbar and abdominal fascia with a fixation clip. Finally, the proximal and distal shunts were attached separately and the procedure was completed with sutures to hold the incision. The average operating time was about 25 minutes. After 3 to 6 months, the visual acuity returned to normal or improved significantly in 27 cases (93%) and no change in visual acuity in 2 cases (7%); diplopia symptoms disappeared in 11 cases (92%); symptoms improved significantly in 2 patients with abducens nerve palsy. There was no lower limb movement, sensory or sphincter dysfunction after surgery. 2 cases had postoperative hypocranial pressure symptoms, which were relieved by conservative medical treatment. 1 case had abdominal end shunt obstruction 10 days after surgery, and the shunt was reoperated and recovered well after surgery. The incidence of postoperative complications was 10%. 3, Discussion Idiopathic increased cranial hypertension, also called pseudotumor cerebri or benign increased intracranial pressure, is characterized by symptoms of increased intracranial pressure and the absence of disease factors such as intracranial tumor, hydrocephalus, infection or hypertensive encephalopathy, and has a relatively good prognosis. The causes may include impaired absorption of cerebrospinal fluid, obstruction of intracranial venous return, endocrine dysfunction, excessive vitamin A intake, and certain blood disorders, but the exact mechanism is unknown.