Freddi Segal-Gidan is Director of the Rancho Los Amigos/University of Southern California (USC) Alzheimer’s Disease Center and Assistant Clinical Professor in the departments of Neurology and Family Medicine at Keck School of Medicine, USC, and in Gerontology at L. Davis School of Gerontology at USC, Los Angeles.
MANAGEMENT The definitive treatment of iNPH is CSF diversion with VP shunt placement. However, as with any surgical procedure, the benefits and risks must seriously be weighed. Since most cases of iNPH involve older adults, many with co-existing, chronic medical conditions, it is important that clinicians undertake a full assessment of the patient’s medical conditions and ability to withstand surgery.
Shunts are inserted into the frontal or occipital horn of the lateral ventricle of the nondominant hemisphere, with tubing connected by a one-way valve directed to the peritoneal cavity. Fixed medium-low pressure valves have largely been replaced by programmable valves that allow adjustment of flow rates. The incidence of shunt complications in recent years has been reduced to about 20%.25
Death or severe postsurgical morbidity occurs in approximately 7% of patients who undergo shunt surgery.26 Subdural hematoma is a common complication whose incidence has been greatly reduced with the use of dual-switch and programmable valves.27 Additional complications include intracranial infection, seizures, intracerebral hemorrhage, mechanical shunt failures, and abdominal injury (ascites, perforation), as well as signs and symptoms of shunt infections (headache, malaise, nausea, fever).
