Roughly 25,000 people are expected to be diagnosed with malignant brain tumors this year in the United States.
The current standard of care for brain tumors includes surgery, radiation and chemotherapy, but recurrence is common and associated with a poor prognosis for the patient. Treating these tumors with systemically delivered chemotherapy is challenged by the blood-brain barrier, a selectively permeable barrier made of endothelial cells that prevents large molecules in the blood — such as chemotherapy drugs — from entering the brain. To work around the blood-brain barrier, doctors have been surgically removing a piece of bone from the skull to directly inject brain tumors with chemotherapy drugs using commercially available, single-port catheters that are not designed for this purpose. Such catheters are ineffective at delivering the drugs to the entire tumor and can leave behind malignant cells.
The problem is, few catheters are designed specifically for use in the brain, and cancer patients need advanced treatment now.
Enter Cockrell School of Engineering associate professor of mechanical engineering Chris Rylander and doctoral student Egleide Elenes. Their innovative new arborizing catheter has multiple biocompatible microneedles made from optical fibers that can spread out like branches on a tree, allowing surgeons to deliver chemotherapy drugs to a volume of the tumor that individual single-port catheters cannot. They can customize the amount and rate of chemotherapy drugs delivered through the individual needles without creating multiple holes in the skull.
The fiberoptic microneedles have the potential to provide the added benefit of simultaneous light therapy that enhances the brain tissue’s ability to absorb the chemotherapy drugs. The Cockrell School researchers are working to incorporate the catheter into an MRI imaging system that will help surgeons to better analyze and monitor the effectiveness of the therapy. The team is currently optimizing the design with the goal of pursuing pre-clinical trials.
