Shaping the Future of Neurosurgery

From investigating novel neuroendovascular treatments for stroke and designing an MRI-compatible robot to remove intracranial hemorrhages to exploring cell therapies that can target glioblastomas, neurosurgical research with the potential to benefit generations of patients is taking place at The George Washington University Hospital.

With key investigatory infrastructure in place, including a dedicated research coordinator for neurosurgical clinical trials and a neurology and neurosciences clinical trials coordinator, GW Hospital is at the forefront of neurosurgical clinical research, stroke care and minimally invasive surgery.

New Approaches to Stroke Treatment

A prime example of the Department of Neurological Surgery’s research efforts is its participation in clinical trials of emerging neuroendovascular therapies for stroke. One such trial involves using metabolomic analysis of blood clots removed from the brain to determine their consistency and potential for medical management. Other trials focus on surgical treatment of hemorrhagic stroke.

“We’re realizing that there hasn’t been much progress with just using medical management, such as blood pressure control or reversing anticoagulation, to treat bleeding in the brain,” says Dimitri Sigounas, MD, FAANS, board-certified neurosurgeon and interventional radiologist at GW Hospital and assistant professor of neurosurgery at George Washington University School of Medicine. “We can make a difference by extracting the blood using minimally invasive surgery. Two of the clinical trials in which we’re participating, the INVEST and MIND trials, are looking at how we can improve patient outcomes by evacuating blood from the brain using minimally invasive surgical devices.”

GW Hospital is also participating in a national, multicenter trial investigating the use of middle meningeal artery embolization to treat subdural hematoma. The trial is investigating a type of glue that allows the neurosurgeon to block blood supply to the brain’s outer covering to maximize patient outcomes.  

Collaborating to Develop and Test New Technologies

Currently, when patients in rural areas need emergent care for intracranial hemorrhages, valuable time is often lost during transfers from local facilities to regional, tertiary care centers. Automating intracranial hemorrhage evacuation could improve patient outcomes—and GW Hospital is collaborating with Children’s National and Vanderbilt University on just such a solution.

With funding from the National Institutes of Health, researchers at the trio of institutions are designing a robot that, with continuous MRI guidance, could position a catheter inside an intracranial hemorrhage and evacuate it, allowing the brain to return to its normal shape as the clot shrinks. Dr. Sigounas is one of the project’s coinvestigators.

“If using the robot is an effective way to treat these hemorrhages in an automated way, one could, potentially, position these robots in peripheral hospitals to perform the procedure there without transferring patients and losing time, during which the hemorrhages may cause significant compression of the brain or neurotoxicity on the adjacent cells,” Dr. Sigounas says. “The robot is in the preclinical stages, and we’re testing it on phantom heads.”

GW Hospital is not just exploring new ways to treat strokes, but also new ways to detect them. An example is the Visor® System by Cerebrotech Medical Systems, which is undergoing testing at GW Hospital and a few other centers around the country. The device uses radio waves to scan the forehead in search of increased bioimpedance on one side of the brain, which may be indicative of a large-vessel blockage. 

Bridging Pediatric and Adult Neurosurgery

One of the newest additions to the Department of Neurological Surgery hopes to bridge the gaps between pediatric and adult neurosurgical care, as well as identify a more effective form of immunotherapy to treat brain tumors. Carlos Sanchez, MD, neurosurgeon and principal investigator at GW Hospital, joined the hospital in October 2021 from Children’s National.

“Cerebrospinal fluid disorders, normal pressure hydrocephalus, pseudotumor cerebri and Chiari malformations are common problems for pediatric neurosurgeons, but adult neurosurgeons see them much less often,” Dr. Sanchez says. “I want to bring the skills I developed at Children’s National as a pediatric neurosurgeon into the adult space. When pediatric patients transition to adult care, pediatric neurosurgery problems can continue, and there’s not really a population of pediatric-trained neurosurgeons who have much experience dealing with these issues.”

Dr. Sanchez also brings a passion for research to GW Hospital. He is studying the use of chimeric antigen receptor (CAR)-modified natural killer (NK) cells to treat primary brain tumors, such as glioblastomas, which have proved more difficult to treat using better studied forms of immunotherapy, such as CAR T-cell therapy. CAR NK cells, Dr. Sanchez says, are less specific in their targeting and activation requirements than CAR T cells.

“The other advantage of CAR NK cells compared with CAR T cells is the ability to scale the CAR NK-cell therapy for many people instead of, essentially, creating a therapy on a patient-by-patient basis, as is the case with CAR T-cell therapy,” Dr. Sanchez says. “CAR NK-cell therapy could be used as an off-the-shelf therapy.”