A Stroke of Sense
Updated: Oct 4, 2019
New research has just been published that may offer new hope to stroke patients. Before we outline the research and what it means we first need a basic understanding of what a stroke is...
A stroke is a serious life-threatening medical condition that occurs when the blood supply to part of the brain is cut off.
Strokes are a medical emergency and urgent treatment is essential.
The sooner a person receives treatment for a stroke, the less damage is likely to happen.
Despite this the damage is often life changing. They are often left with long-term problems caused by injury to their brain and the neurons and other cells that make it.
Some people need a long period of rehabilitation before they can recover their former independence, while many never fully recover and need support adjusting to living with the effects of their stroke.
Types of Stroke
In the following diagram we can see the 2 major types of stroke that can occur:
Ischemic Stroke - caused by a clot or plaque.
Haemorrhagic Stroke - caused by a burst aneurysm or a torn artery.
Treatment is dependent on the type of stroke that has occurred. An ischemic stroke's main goal in treatment is to bust or remove the clot. This is done via:
medication such as Altephase IV r-tPA.
Physical removal of a large blood clot, called an endovascular procedure or a mechanical thrombectomy, is another strongly recommended treatment option. Thrombectomy allows trained doctors to use a wire-cage device called a stent retriever to remove a large blood clot. To remove the clot, doctors thread a catheter through an artery in the groin up to the blocked artery in the brain. The stent opens and grabs the clot, allowing doctors to then remove the stent with the trapped clot.
A haemorrhagic stroke is treated differently as its treatments main aim is to stop the bleeding. This is done by:
A small tube called a catheter can sometimes be threaded up through a major artery in an arm or leg and guided into the brain tissue, allowing the surgeon to use camera technology to help fix the problem. Once the catheter is guided to the source of the bleeding, it deposits a mechanical agent, such as a coil, to prevent further rupture.
This type of procedure is endovascular, meaning that the surgeon gains access via the vascular system, making it less invasive than conventional surgical treatment. Sometimes surgery is required to secure a blood vessel at the base of the aneurysm.
The challenge isn't over at this point however as the next phase, recovery and reduction in the likelihood of having another stroke is often challenging.
A team led by Jin-Moo Lee of Washington University, St Louis have been conducting studies on mice and uncovered fascinating results that offer new hope and a potential new way to treat those recovering from the effects of a stroke.
What they did...
The team behind this new research gave mice strokes in regions of their brains that were linked to sensations from their forepaws on their right side. They then trimmed the whiskers off of the mice, so disrupting one of their key senses. They made sure to maintain this for 8 weeks.
Amazingly mice that had their whiskers trimmed off recovered sensation in their forepaws within 5 weeks. This was compared to 7 weeks for those mice without trimmed whiskers, whom also never re-gained full sensation.
When the team imaged the brains they noted that it was evident the brains of the mice whom had their whiskers trimmed had undergone significant remapping of the brain, by which the area linked to whisker sensation had been rewired to help the recovery of the stroke affected region.
The study is the first to demonstrate a novel idea that certain aspects or regions of the brain can be made to be more receptive to rewiring, thus acting as a tool to accelerate and ultimately improve the outcomes of stroke patients.
Science Translational Medicine, DOI:10.1126/scitranslmed.aag1328