Why we should care about the bog in our brains
In the world of medical research, neurologist Dr. Sandra Black is one of Canada’s most valuable resources.
She has published hundreds of peer-reviewed papers, dozens and dozens of book chapters and articles, close to 700 conference abstracts, and presented more than 500 invited lectures. She has the Order of Ontario. She is a Fellow of the Royal Society.
But what distinguishes her most?
She is on the leading edge of discovery. She is an unconventional thinker. And she is one of only a few physician-scientists in the world with expertise in stroke, dementia and Alzheimer’s – three conditions linked by damaged small blood vessels in the brain.
“I say I’m an Alzheimer strokologist or a vascular dementia expert,” says Dr. Black, a research leader in the Heart and Stroke Foundation Canadian Partnership for Stroke Recovery (CPSR) and a senior scientist at Sunnybrook Health Sciences Centre. “In my world, Alzheimer’s and Vascular Disease often live together as one.”
Small vessel disease – probably the most common pathology in the aging brain – is important on several fronts:
• clogged and diseased small vessels can lead to the development of a major stroke;
• small vessel disease can result in tiny, undetected strokes (sometimes called silent or covert strokes) that lead to dementia and Alzheimer’s; and,
• importantly, leakage around this multitude of microscopic diseased vessels, especially the small veins, create what Dr. Black calls “a bog” or “a stagnant cesspool” deep in the brain, making recovery from stroke much more difficult.
“The relationship between small vessel disease and stroke recovery is a huge issue,” she explains. “But only in a place like the Partnership can you make it a research focus. The CPSR is the right stewing pot to allow these ideas to emerge and to be developed.”
For the past 10 years, Dr. Black, who runs a busy vascular cognitive impairment and dementia clinic at Sunnybrook, has been studying brain scans, measuring and counting small strokes and looking at changes to white matter (the part of the brain that coordinates communication among different regions).
“Small vessel disease has got to be measured in order to be understood and managed,” Dr. Black says. “Disease in the white matter of the brain impairs recovery from stroke” and destroys the body’s own stem cells that promote repair.
By understanding the scope of small vessel disease and its relationship to stroke, dementia and Alzheimer’s, prevention and treatment strategies can be developed.
As she works to crack the code of small vessel disease, Dr. Black is energized by other new frontiers in recovery research, including:
• the use of focused ultrasound through the skull to repair stroke and treat dementia by opening the blood-brain barrier in damaged areas and delivering targeted drugs to promote recovery or prevent neurodegeneration;
• the use of transmagnetic stimulation in combination with speech therapy to turn on underperforming communication centres in the brain that have been damaged by stroke;
• the development of cognitive therapies to help improve memory and reasoning after stroke; and,
• new individualized approaches to get people motivated to exercise and improve their brain health after stroke through the use of new technologies.
In the meantime, Dr. Black will push ahead to promote understanding of the stroke-dementia-Alzheimer’s link, and to improve application of research to benefit patients and families everywhere.