Dr. Mark Hamilton

Cerebrospinal fluid (CSF) shunts are the most frequent type of surgical treatment for hydrocephalus which most commonly redirects some of the CSF from the brain into the abdominal cavity. External drains are sometimes required to monitor brain pressure or temporarily remove CSF. Patients undergoing a shunt or drain surgery have a significant risk for developing infection (6%-15%). Shunt and drain infections can have devastating effects on patients, risking the loss of neurological function or death. In addition, the treatment of these infections results in prolonged hospital stays and significantly increases healthcare costs. Previous pilot experience has demonstrated that infections can be significantly reduced with the adoption of protocols that establish how shunt surgery and drain insertion surgery are done to avoid this risk. The protocol for shunt infection prevention has been piloted for the Adult Hydrocephalus Program, in Calgary and resulted in a reduction in shunt infection from 6% to <1%. This project will introduce these protocols to all Alberta hospitals where adult neurosurgery is undertaken using interactive Quality Improvement methodology. We are engaging patients and families for input regarding study methods and will monitor infection rates to verify success. The reduction of infection rates will significantly benefit patients and their families and has the potential to reduce health care costs by approximately $10,000,000 over 3 years.

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), working with 13 other health centers, hope 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 AHCRN was founded for the purpose of increasing awareness and understanding of adult hydrocephalus, accelerating research, and improving treatments for adults with hydrocephalus (http://www.ahcrn.org/about-ahcrn/).

Four categories of adult hydrocephalus are defined: 1) transition—patients who were treated for hydrocephalus of any etiology before the age of 18 years; 2) unrecognized congenital—patients with imaging features, or enlarged head circumference, or both, determined to be consistent with congenital hydrocephalus but who were not recognized or treated before the age of 18 years; 3) acquired— patients with hydrocephalus secondary to known risk factors (e.g., subarachnoid hemorrhage, brain tumor), whether treated or untreated; and 4) suspected iNPH (SiNPH)— patients age ≥ 65 years referred for the evaluation of iNPH who had not previously received surgical treatment.

The registry includes entry criteria, demographics, hydrocephalus category and etiology, medical history, comorbidities, medications, symptoms, examination findings, previous and current surgical procedures (shunt or endoscopic third ventriculostomy), and imaging studies. Standard evaluations are administered to all subjects. To ensure consistency of the testing, all examiners are trained and required to demonstrate competency for the administration and interpretation of the evaluations.