Medical student completes groundbreaking research on use of histotripsy in treatment of brain tumors

When Maya Langman, a fourth-year student at the Virginia Tech Carilion School of Medicine (VTCSOM), was selecting a research project that she would pursue all four years of school, she wanted to make a major difference. Now, the aspiring neurosurgeon’s research is being lauded as being the first of its kind with the possibility to lead to innovative treatment for brain cancer.

Langman worked in the lab of her mentor, Eli Vlaisavljevich, associate professor of biomedical engineering and mechanics and director of the Therapeutic Ultrasound and Noninvasive Therapies Lab at Virginia Tech. Vlaisavljevich is internationally renowned for his development of novel uses for histotripsy therapy.

Histotripsy is a noninvasive, focused ultrasound therapy that is able to ablate cancerous tumors in different areas of the body. One area that has presented limitations, however, is the brain. Due to the bone density, the skull acts like a barrier that causes a reduction in the power of ultrasound waves as they pass through it. Langman’s work focused on how to make histotripsy therapy more feasible for the brain.

She is one of nine students to receive a Letter of Distinction for her research, and she will provide an oral presentation at VTCSOM’s annual Medical Student Research Symposium, which is from noon-5 p.m. March 24.

Langman was paired with graduate student Lauren Ruger, and for four years, the two were dynamic research partners and friends.

“I joined the lab not having a mechanical engineering background, so there was a steep learning curve. Lauren has been a fantastic teacher and partner over the past four years. Now I’d like to bring the field into my clinical career moving forward,” Langman said.

In order to overcome the barrier of the skull, Langman started her research by testing the acoustic properties of a recently developed cranial implant. The implant is an opaque sonolucent material that acts like a window that allows ultrasound transmission into the cranial space with minimal distortion. The implant had previously proved to be effective in bedside monitoring for brain tumor regrowth and in combination with other focused ultrasound modalities for opening the blood-brain barrier. However, it had not been investigated for use with histotripsy for brain tumor ablation.

In early testing, Langman used a transducer to test a series of ultrasound parameters to investigate the feasibility of histotripsy treatments through the implant. It proved difficult to overcome the barrier effect of the implant with their prototype transducer. They are hopeful that with future device iterations histotripsy ablation through the implant will be possible.

Then the research took a new direction. Working with her research partners in the lab as well as a team from the Virginia-Maryland College of Veterinary Medicine at Virginia Tech, Langman helped facilitate the first-ever histotripsy brain tumor ablation in a clinical patient. The patient was a dog with a benign tumor called a meningioma. The procedure removed a part of the animal’s skull allowing the team to use histotripsy to treat the dog’s tumor through an open window.

The dog responded well to the procedure with no adverse effects.

“This is the first time histotripsy has been used to ablate a brain tumor in a clinical patient,” she said. A second dog was treated with success. The team plans to treat at least four more over the course of the pilot series.

“The two things we want to prove are that this procedure is safe and effective,” she said. “There is so much promise with this therapy.”

Langman describes her time in the Vlaisavljevich lab as one of the highlights of medical school.

“Dr. Vlaisavljevich has a brilliant mind and is constantly pushing us to think beyond the current problem,” she said. “He is what you picture as the best type of mentor who is pushing you to question ‘what else.’”

Team members presented their research at a professional conference in the fall and have been accepted to showcase their work at an international conference this spring. Langman hopes to continue to integrate focused ultrasound research into her clinical career as her residency placement allows.

“Maya’s research has made significant contributions to the development of histotripsy as a new noninvasive therapy for the treatment of brain tumors,” Vlaisavljevich said. “She has set an amazing example of how to conduct groundbreaking interdisciplinary biomedical research within a team environment.”

“Focused ultrasound is such an incredible modality,” Langman said. “There’s so much more than can be done. I think we’re just at the tip of the iceberg.”

Langman and other members of the Class of 2023 will be the medical school's 10th graduating class when commencement exercises are held on May 6.