The odds of suffering an intracerebral (IC) hemorrhage during your lifetime (1 in 50) are almost as terrifying as the as the chances are that it will kill you (4 in 10) if it does happen. IC hemorrhages (and the edemas, or clots, they produce) account for 11 per cent of all strokes, and are far more likely to severely disable you than the effects of a lesser ischemic stroke. But this clot-busting device might just turn the odds in your favour.
The medical community generally agrees that removing 20-50 per cent of a clot can drastically improve a patient’s survivability, but that option comes at the cost of the parts of your brain that must be removed to access any clot below its surface. Plus, surgical teams conventionally had to open large holes in your skull just to get access in the first place, which of course leads to more serious infection. And by “skull”, we’re also talking the front, facey part of it. As such, medicine’s best course of treatment is to simply wait and see what happens while administering anti-inflammatories to reduce the intracranial pressure.
But simply hoping for the best isn’t good enough for a team of researchers from Vanderbilt University. Led by Assistant Professor Robert J. Webster III and Assistant Professor of Neurological Surgery Kyle Weaver, the team has developed a robotic surgical tool that will suck out the clot clean out of your nose.
“Transnasal” surgery is nothing new; the Egyptians used a variation of it when removing the brains of mummification candidates. By going through the sinus cavity, doctors can access the brainpan with far less trauma than conventional methods, but only a few surgeons in the world have hands steady enough for such a delicate task.
Webster’s system takes the shaky hands out of the equation entirely. His active cannula system works like this: First, doctors perform a CT scan of the patient’s head, pinpointing the location of the clot. Then, based on that information, the lead surgeon will determine the best place to enter the skull and access the clot while minimising damage to the brain itself.
The surgical team will then set up the body of the device, dubbed the trajectory system, immediately above the access hole that the team has drilled into the patient’s skull. The trajectory system inserts a pair of nested tubes less than 1/20th of an inch in diameter through that hole.
The tubes themselves are quite ingenious. The straight outer sleeve covers a series of rigid, precisely curved inner tubes. By manipulating out these individual inner tubes, surgeons can navigate the tip of the device around the inside of the skull. Once the tip of the outer tube hits the clot, it extends the inner tube into the mass, whereupon the surgeons hook the device to a suction pump and hoover out the bloody pulp.
“The trickiest part of the operation comes after you have removed a substantial amount of the clot. External pressure can cause the edges of the clot to partially collapse making it difficult to keep track of the clot’s boundaries,” said Webster in a press statement. Even so, the system has shown that it can access and remove more than 90 per cent of simulated blood clots.
The device is still far from achieving FDA approval but the team is already working to incorporate a more accurate ultrasound-based guidance system, as well as developing computer models of how grey matter deforms under stress to better predict how the surrounding tissues will respond during the procedure. In any case, it’s probably better than the current method could provide in the best of situations. [Vanderbilt University, Medscape Reference]