The most effective treatment for INPH is still cerebrospinal fluid shunts, including ventriculo-ventricular shunt, ventriculo-atrial shunt, lumbar pool ventriculo-ventricular shunt, and triple ventricular drainage. The ventriculo-abdominal shunt is the most commonly used. The shunt has evolved from a simple differential pressure valve in the early years to an anti-siphon device and a flow restriction valve as well as an adjustable (programmable) valve. They can also be classified as low, medium, or high pressure depending on the pressure at which the valve opens. Adjustable valves can solve excessive or insufficient shunts by adjusting the shunt speed without surgery and solve complications such as shunt obstruction [2 citation needed. The prognosis of INPH shunts has improved greatly with the coming improvements in technique and equipment. After surgery, gait impairment improved the most, followed by cognitive function, and urinary incontinence improved relatively poorly. In addition the timing of surgery is an important factor in prognosis, early diagnosis and early treatment are directly related to the efficacy of bypass surgery.