Wanting to be a surgeon I naturally
looked for surgical procedures that may help stroke. Now, this does NOT mean I want to wave around
my scalpel stabbing everyone and their mothers. Being so invasive, surgery should, for the
most part, be thought of as a last resort.
However, as techniques and new devices advance it could start to be
viewed as less invasive than powerful chemicals.
One
such device is called SHELTER (Stroke Help using an Endo-Luminal Transcatheter
Embolus Retrieval). It does exactly what
it implies: it physically grabs the embolus.
However, this is much different than the catheters we are used to. It has an outer sheath and for capturing the
clot and an inner rod housing a collapsible metal umbrella. This umbrella has holes
to let non clotting RBCs through while capturing the actual clot. It also has a
soft springy polymer coating to prevent vessel puncture.
SHELTER is the first device to both filter and remove clots,
the first to entrap the clot from both its near and far ends, and the first
capable of accessing small vessels in the brain.
What may be even more impressive is their silicone model
used to test the device. They say in
many ways it is a more accurate test than using mice. This could be possible, after all mice or not
people. But then again, silicone is not
flesh. Nonetheless the testing model is
a silicone copy of human cadaver blood vessels and can even have aneurisms,
atherosclerosis and "plaque.”
I would imagine this testing would not only cut back on
animal models but also serve as a more accurate way for physicians to train
their SHELTER abilities.
The “window” for saving vital brain matter closes around 2
hours for clot busters. After those 2
hours the clot buster has a hard time fixing anything. With this device that window is wide open for
a longer period of time.
But we must still keep in mind that this is a surgery and
can cause complications of its own.
The link shows some very interesting
videos from the brothers than made this device. I HIGHLY recommend watching the videos if you are as big of a nerd as I am and love this stuff.
http://medgadget.com/2010/06/shelter_for_emergency_stroke_therapy.html
Oops! Forgive me, I got so excited with the article I completely forgot to even explain what stroke is! Also called a brain attack, a stroke is when blood flow to any part of the brain stops. The problem of a stroke comes from the fact that brain tissue can die off rather quickly when it is cut off from oxygen, glucose, and other nutrients carried by the blood.
ReplyDeleteTwo major types of stroke is ischemic (which was covered in class) and hemorrhagic. Ischemic strokes occur either from an embolism or narrowing of the vessel itself. Hemorrhagic strokes happen when a blood vessel bursts. Ischemic strokes are solved by removing the clot either with clot busting chemicals or physically removing it. Hemorrhagic strokes are a little more complicated. Drugs to control brain swelling are one of the more common treatments.
This is really cool! Devices like this really show how engineering and medicine can work together to create things that can really help treatment of various disease states. Yay biomedical engineering!
ReplyDeleteI did a little googling to see what the status of the device was as far its status with the FDA and getting approved for clinical use. It looks like currently the device has been used on a few patients in India and the company, Insera, hopes to begin domestic clinical trials late this year. I'll be interested to see how the device compares to current treatments methods.
http://www.haimovitchmedtech.com/articles-stroke-2011-MDD-2.html
Also, this article shows a better picture of their silicone model, which looks pretty cool:
http://questional.com/blog/171-gimmie-shelter-advances-in-stroke-treatment/
While I was poking around on Medgadget today I found this recently FDA approved device for retrieving thrombi:
ReplyDeletehttp://medgadget.com/2012/03/covidien-solitaire-fr-device-for-ischemic-stroke-treatment-gets-fda-nod.html
The shelter definitely seems like it will be more reliable as it provides a way to hold the clot together as you're pulling it out. It seems that with the SWIFT device you may have the issue of the clot breaking into smaller pieces as it is removed. However, this problem must not be too common if the FDA gave it a green light. It'll be interesting to see which device becomes more desirable by doctors in the future.