AHCRN Awarded $14 Million NINDS Grant to Study Effectiveness of Shunt Treatment for idiopathic Normal Pressure Hydrocephalus

Largest grant ever awarded to study adult hydrocephalus.

It is estimated that more than 700,000 Americans have Normal Pressure Hydrocephalus (NPH). NPH is one of the few causes of dementia that can be improved through direct treatment.

Idiopathic Normal Pressure Hydrocephalus (iNPH) is a complex disorder of the elderly that is caused by an excess accumulation of cerebrospinal fluid in the brain and includes symptoms of dementia, difficulty walking, and impaired bladder control that affects as many as 700,000 persons in the U.S. The only treatment is for a neurosurgeon to implant a permanent internal drainage system called a shunt into the brain to drain the excess cerebrospinal fluid. However, not everyone in the medical community agrees that shunt surgery is an effective treatment for iNPH, and, as a consequence, many patients who could benefit from shunt surgery do not receive it.  Now, thanks to a $14 million National Institute of Neurological Disorders and Stroke (NINDS) grant, the largest grant ever awarded to study adult hydrocephalus, the 8 sites of the Adult Hydrocephalus Clinical Research Network (AHCRN)1, working with 13 other health centers2, hope to change that perspective with a study designed to prove conclusively whether shunt surgery for iNPH is beneficial.

The NINDS funded grant, called “A Placebo-Controlled Efficacy in iNPH Shunting (PENS) Trial” will be the first large scale, multi-center, blinded, randomized controlled trial to evaluate the true response of shunting in patients with iNPH.

“This grant will allow the AHCRN to use its network of neurosurgeons, neurologists, and medical institutions to conduct a clinical trial that will finally give us the answers we’re looking for about whether shunting is an effective treatment for iNPH,” explained Dr. Mark Hamilton, Neurosurgeon, AHCRN Chair, and Vice Chair of the Hydrocephalus Association Medical Advisory Board.

The study is being conducted in partnership with the Johns Hopkins Cerebral Fluid Center. Johns Hopkins will also serve as the primary coordinating center.

“This study is important because right now some in the medical community are not convinced that shunts are an effective treatment for iNPH. Much of this uncertainty is due to the lack of a high-quality randomized controlled trial,” said Dr. Mark Luciano, Neurosurgeon, Director of the Cerebral Fluid Center at Johns Hopkins and Principal Investigator of the study.

During the PENS trial, 100 patients with iNPH who are undergoing shunt surgery will be randomly assigned to one of two groups, either with the shunt valve open (on) or closed (off) for the first 3 months after surgery, after which all shunts are in the open setting. The shunt valves can easily be adjusted to an open setting in the clinic with a simple tool that does not require additional surgery. Evaluations before and after surgery will compare the response of iNPH symptoms such as slowed walking speed, impaired cognition, mood, and bladder control at the end of 3 months in the two groups and will continue to follow the symptom response in all patients for the following year while all shunts are in the open setting.

The AHCRN, one of three research networks funded by the Hydrocephalus Association (HA), is a network of eight hospitals that conducts clinical research to improve treatment for the adult forms of hydrocephalus.

About the Hydrocephalus Association  

Founded in 1983 by the parents of children with hydrocephalus, the Hydrocephalus Association (HA) is the nation’s largest and most widely respected organization dedicated to hydrocephalus. Since 2009, HA has invested over $13 million in research, making it the largest non-profit and non-governmental funder of hydrocephalus research in the United States. The Hydrocephalus Association’s mission is to find a cure for hydrocephalus and improve the lives of those impacted by the condition.


  • AHCRN Centers:
    • Cleveland Clinic, Cleveland, Ohio, USA
    • Columbia University Irving Medical Center, New York, New York, USA
    • Johns Hopkins University, Baltimore, Maryland, USA
    • New York University Langone Health, New York, New York, USA
    • University Hospitals Bristol, Bristol, UK
    • University of British Columbia, Vancouver, British Columbia, Canada
    • University of Calgary Foothills Hospital, Calgary, Canada
    • University of Washington Medical Center, Seattle, Washington, USA
  • Additional Centers:
    • Emory University, Atlanta, Georgia, USA
    • Henry Ford Health System, Detroit, Michigan, USA
    • Icahn School of Medicine at Mount Sinai, New York, New York, USA
    • Indiana University School of Medicine, Indianapolis, Indiana, USA
    • Mayo Clinic, Rochester, Minnesota, USA
    • Oregon Health and Science University, Portland, Oregon, USA
    • Rush University, Chicago, Illinois, USA
    • Umea University, Umea, Sweden
    • University of California Davis, Sacramento, California, USA
    • University of New Mexico, Albuquerque, New Mexico, USA
    • University of South Florida, Tampa, Florida, USA
    • University of Texas Southwestern, Dallas, Texas, USA
    • Wake Forest University, Winston-Salem, North Carolina, USA