The most common type used to treat NPH is ventriculoperitoneal (VP) shunts, which drain CSF fluid to the peritoneal cavity. Adjustable valves allow fine-tuning of CSF drainage. NPH symptoms reportedly improve in 70–90% of patients with CSF shunt. Risk-benefit analyses have shown beyond any doubt that surgery for NPH is far better than conservative treatment or the natural course.Gait symptoms improve in ≥ 85% patients. Cognitive symptoms improve in up to 80% of patients when surgery is performed early in the disease course. Urgency and incontinence improves in up to 80% of patients, but only in ≤ 50–60% of patients with shunt implanted late in disease course. The most likely patients to show improvement are those who show only gait deviation, mild or no incontinence, and mild dementia. The risk of adverse events related to shunt placement is 11%, including shunt failure, infections such as ventriculitis, shunt obstruction, over- or under-drainage, and development of a subdural hematoma. Medications
No medications are effective for primary NPH. Acetazolamide and other diuretics are not recommended except for limited use in patients who are not candidates for placement of a shunt. Epidemiology
The majority of cases are primary NPH. Incidence is estimated to 0.3–3% in patients older than 60 years and raising with older age  Its prevalence is reported to be less than 1% in persons under the age of 65, and up to 3% for persons aged 65 or older. No difference in incidence is seen between men and women.
Among individuals with dementia, the incidence of NPH is thought to be between 2 and 6%. See also
Low pressure hydrocephalus

References
External links
The Normal Pressure Hydrocephalus Center at Johns Hopkins Bayview Medical Center
Normal Pressure Hydrocephalus at Cleveland Clinic
normal_pressure_hydrocephalus at NINDS
When it really is NPH at Likvor
Hydrocephalus in Adults at Spina Bifida Resource Center