DECONSTRUCTING CONCUSSION
The effects of concussion can linger after a head injury, sometimes for an extended period of time. Headaches, trouble concentrating, forgetfulness, unusual tiredness and trouble with balance are common symptoms.
In some cases, a premature return to work or other activity can worsen these symptoms and make them last longer.
"Unfortunately, doctors are often left to do a lot of guesswork as to when an individual is best fit to return to regular activity, as there currently is no good objective indicator of readiness to return to an activity, whether it be work, a professional sport or recreational [in nature]," says Dr. Leodante da Costa, a neurosurgeon at Sunnybrook.
Dr. da Costa and his research team wanted to find a solution to the lack of objective criteria to assess patients with brain injuries. They are using a unique technique for precisely measuring the brain's vascular response to the stimulus of carbon dioxide (CO2) during MRI scans.
"The technique is similar to breathing in a paper bag, but the inhaled and exhaled gases are precisely measured," says Dr. da Costa. "It's a breathing challenge that acts as a stress test for the brain."
In the study, a precise amount of CO2 is given through a breathing mask while the patient is still in the MRI. The CO2 causes an increase in the size of healthy vessels, and a specialized imaging technique known as a BOLD sequence is taken to measure the changes in oxygen inside the vessels. If the vessels don't react to CO2, the brain could still be recovering from trauma.
The researchers hope to develop an imaging marker of recovery for concussion that doctors can use to more objectively measure when it is safe for patients to become active again.
Dr. da Costa's team was the only Canadian group to receive funding for their study from the GE-NFL Head Health Challenge.
GETTING A BETTER HANDLE ON SUPERBUGS
Forewarned is forearmed. That's why Sunnybrook researchers are helping to more frequently survey and assess the presence of superbugs, or antibiotic-resistant organisms, in Canadian hospitals. Their goal is to better inform infection prevention and control programs, and to stem the tide of antibiotic resistance, which has been declared a major threat by the Public Health Agency of Canada and the World Health Organization.
Dr. Andrew Simor, chief of Sunnybrook's Microbiology Department, and the Division of Infectious Diseases, and his team are measuring the impact of antibiotic resistance and demonstrating to the medical community that careful use of antibiotics is critical to patient health.
Dr. Simor led the first national survey of prevalence rates in more than 176 acute-care hospitals. The 2013 report provided a much-needed baseline and more detailed national picture of rates of superbugs like MRSA (methicillin-resistant Staphylococcus aureus) and VRE (vancomycin-resistant enterococci) and the related CDI (Clostridium difficile infection).
His follow-up survey published in 2015 found that on any given day, at least one in 11 patients across the country carries or is infected with an antibiotic-resistant organism. The report identified a number of important infection prevention and control practices that were associated with lower antibiotic-resistance rates.
This study was the first to provide national prevalence results for multidrug-resistant superbugs in Canada.
"The more we know on a timely basis about what's happening in hospitals across the country, the more equipped we are to stop antibiotic-resistant bugs from growing and spreading," says Dr. Simor. •
NEW TERRAIN FOR TAVI
Sunnybrook is breaking new ground on the minimally invasive transcatheter aortic valve implantation (TAVI) procedure for an entirely new group of patients deemed too high risk for open-heart surgery.
Sunnybrook pioneered the use of the TAVI procedure to repair the aortic valve of patients who are too frail to withstand open-heart surgery. It involves loading a collapsible replacement valve into a catheter and sending it through an artery up the leg and through to the aortic valve. Here, the new valve sits inside the damaged one and takes over the job of regulating blood flow.
Recently, Sunnybrook experts were among the first in Canada to implant TAVI valves, made from artificial material and designed for the aorta, inside one patient's failing artificial mitral valve and inside another patient's artificial tricuspid valve.
These are patients whose own valves failed years ago and who had surgery to implant replacement tissue valves. But these tissue replacement valves have a limited life span, says cardiovascular surgeon, Dr. Gideon Cohen. They become calcified and degenerate over time, typically lasting up to about 10 years.
"What's different about this new procedure is the use of TAVI technology to replace valves other than the aortic valve," says Dr. Cohen, who performed the new procedure with cardiologists Dr. Sam Radhakrishnan and Dr. Harindra Wijeysundera. "This is much less risky, it's a much quicker recovery and you get the same result as surgery."
All TAVI procedures at Sunnybrook were once funded entirely through the generosity of donors. Convinced of its efficacy after Sunnybrook experts saved more than 150 lives with TAVI, the procedure is now funded by the provincial government. •
SLEEP AWAY THOSE TOXINS
Cleanses are all the rage, but how about detoxing your brain? A Sunnybrook research team has a simple fix: good-quality sleep.
"Sleep may play an important role in clearing waste and toxins in the brain that may contribute to the development of brain diseases," says Dr. Mark Boulos, a stroke and sleep neurologist in the Hurvitz Brain Sciences Program at Sunnybrook.
Unlike other organs in the body, the brain doesn't have a dedicated lymphatic waste removal system. Instead, researchers believe it uses fluid-filled channels that surround the brain's blood vessels to drain toxins and waste products away.
The Sunnybrook research team looked at MRI brain scans and overnight sleep studies from 26 patients who were being evaluated for stroke or a suspected cerebrovascular event. Using MRI brain scans, researchers could see that those with poor-quality sleep, or "choppy" sleep with frequent waking, had more enlarged channels around their brain's blood vessels than those with healthy sleep patterns. Researchers believe that could be a result of a buildup of toxins.
Dr. Boulos says the research could potentially provide a novel treatment option for patients living with the effects of stroke or other brain diseases.
Should you worry about the occasional night of bad sleep? "If you have a sleep problem, see your doctor about improving your quality of sleep," says Dr. Boulos. "Don't just attribute poor sleep to your age or an underlying health condition. It's good to have it checked out because, over the years, it could have implications for your overall health."
That's advice to sleep on. •
This content was produced by The Globe and Mail's advertising department, in consultation with Sunnybrook. The Globe's editorial department was not involved in its creation.