To say that the surgery to remove blood clots in the brain is difficult would be an understatement. To remove the clots, a large hole needs to be drilled into the skull and healthy brain tissue is usually disturbed. The surgery is so risky, doctors frequently skip the procedure, prescribe anti-inflammatory drugs and cross their fingers — not such great news, especially since 40 percent of cases are fatal.
However, a team of physicians and engineers, led by Robert J. Webster III and Kyle Weaver from Vanderbilt University, have built a robotic device designed to remove brain blood clots with a less invasive method. The device utilizes a needle-equipped cannula, a thin tube that’s inserted into the brain to suck the clot out from the inside.
First, a small hole, adjacent to the clot, is made in the skull. The device itself actually is a tube within a tube, of which, the straight outer tube is less than 1/20th of an inch in diameter.
Using a CAT scan for guidance, the robotic device carefully pushes the outer tube into the brain, until the tip enters the clot. Then, an inner needle with a curved tip enters the clot. This needle is attached to an external pump and can therefore suck out the blood clot from the inside. Because of their steerable nature, the needles can pass around, instead of through vital parts of the brain.
In lab simulations, the robotic cannula removed 92 percent of a blood clot on a gelatin brain mold. Researchers are now developing ultrasound imaging to supplement their device and a computer model of how healthy brain tissue deforms around a clot. Check out this video, as researchers give an inside tour of their work.
Credit: Vanderbilt University