WHICH COMES FIRST: SLEEP PROBLEMS OR STROKE?
It's scientifically established that people who have had a stroke have a propensity toward sleep disorders. New research at Sunnybrook is finding a sinister two-way link: Sleep problems such as sleep apnea and periodic limb movements – the nighttime leg kicking common in restless leg syndrome – may be harbingers of serious health problems such as heart attack and stroke.
"There is pretty solid evidence that sleep apnea is associated with cardiovascular disease, stroke and death," says Dr. Mark Boulos, a Sunnybrook neurologist and expert in sleep and stroke. "Now research is demonstrating that periodic limb movements may be associated with future cardiovascular disease and possibly stroke."
The usual culprits that cause clogged arteries – high blood pressure, high cholesterol, inflammation, diabetes, obesity, elevated heart rate – can also result in limited blood flow to the brain. Sleep disorders can exacerbate those risk factors.
State-of-the-art brain imaging at Sunnybrook is showing the world how important it is to keep blood vessels clear in both the body and the brain: In the aging brain, especially with vascular risk factors, white spots show up deep inside; what neurologists call "white matter hyperintensities." These hyperintensities reflect small vessel disease and are associated with stroke, dementia and earlier death.
Dr. Boulos's research has found that people who kick while they sleep also have greater incidence of small-vessel disease of the brain.
"This is an important area of study," says Dr. Sandra Black, director of Sunnybrook's Brain Sciences Research Program. "The link between sleep disorders, vascular disease and dementia is becoming increasingly more established, through imaging technology and careful clinical observation."
The good news is that sleep disorders may be reversible. "If you have a sleep disorder, see a doctor," says Dr. Boulos. "There may be a treatment that will make you feel better and may reduce your risk of heart attack and stroke."
A PROMISING TREATMENT
"Gold nanobombs to treat breast cancer" sounds like science fiction, but promising research is already underway. Researchers at Sunnybrook's Odette Cancer Centre and the University of Toronto have developed an assembly of tiny gold particles (nanoparticles) and antibodies that attach to cancer cells, and a radioisotope, which, upon decay, provides a highly efficient radiation treatment.
Nanobombs would be injected into and around the tumour using brachytherapy, a technique where a tiny radioactive source is inserted into a cancer growth. The hope is that nanobombs will better target treatment for early stage and locally advanced breast cancers.
"The technology would allow us to focus the radiation killing effect into the cancer cells by implanting them with nanobombs and trapping cancer's spread, as nanobombs follow the same route as the cancer. That could be a much more efficient treatment," says Dr. Jean-Philippe Pignol, Sunnybrook radiation oncologist and scientist, who is leading this research, working with Dr. Raymond Reilly, a radiopharmaceutical scientist at the University of Toronto.
Dr. Pignol, an expert on brachytherapy, pioneered the one-day radiation treatment for early stage breast cancer using tiny, permanent radioactive seeds implanted after a lumpectomy. Combining nanotechnology and brachytherapy, he is developing a new form of implantable seeds to encase the nanobombs. The seeds would be readily absorbed by the body, after treatment.
"Treatments must adapt to the patient," he says. "Nanobomb seeds would be simple, portable and could be used in remote communities where it is difficult to access high-tech radiation treatment facilities."
3-D SURGICAL GAME-CHANGER
Enhanced precision in the operating room is something that every surgeon wants, especially during a brain or spine operation. Surgical navigation uses 3-D imaging to accurately track surgical instruments and a patient's anatomy, providing real-time information. Dr. Victor Yang, a Sunnybrook neurosurgeon and Ryerson University engineering professor, is poised to place made-in-Ontario technology on the international medical scene by creating a solution that is easier to use, faster and more cost-effective than current options.
Using surface imaging, Dr. Yang and his team have designed a solution that aligns the patient's anatomy with preoperative images. Registration takes only seconds for the surgical team, a radical improvement in speed. Not only that, the solution is inexpensive, making it an appealing option for developed countries, and the developing world.
"By decreasing surgical time and maintaining accuracy, there is an absolute improvement in patient safety and also a reduction in surgical complications," says Dr. Yang, whose team has started a company called 7D Surgical Inc. to commercialize the surgical navigation solution.
A CLEAR CASE FOR A BETTER VIEW
When it comes to rebuilding a patient's injured face, surgeons turn to screws, plates and wires. Often there's a high post-surgery complication rate, and often the need for one or more follow-up operations. Drs. Cari Whyne, Jeff Fialkov and their team in the Holland Musculoskeletal Research Program at Sunnybrook set out to discover why.
"Dr. Fialkov wondered if the reason for these high complication rates is over-engineering – we are putting many plates and screws into very thin bones, but we don't really know how loads travel through the complex craniofacial structure," says Dr. Whyne. "If we better understand how loads from activities like chewing travel through these bones, we could do a better job of designing and placing implants and performing the surgeries."
When they began investigating, one thing became clear right away: Clinical CT scans aren't clear enough. "Even very good patient CT scans give blurry images of the craniofacial bones, and that changes the geometry and intensity of the bone structure. It doesn't allow us to accurately model what is going on in the face," says
So the researchers designed a way to make regular CT images much clearer and offer more accurate representations of the skull. This is done using new image-processing software that deblurs the images based on known properties of thin bone. These images show the location of the thin bones that don't always appear on a regular CT. Patients don't need extra or more powerful scans. It's all left to this new postimaging technology. •
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.