Lawson Health Research Institute (Lawson) has long been a leader in biomedical imaging. The first Canadian magnetic resonance imaging (MRI) of a human occurred at St. Joseph’s Health Care London (St. Joseph’s). The country’s first positron emission tomography/computed tomography (PET/CT) and positron emission tomography/magnetic resonance imaging (PET/MRI) scanners were also installed at St. Joseph’s. New developments in imaging research continue to enhance the diagnosis, prevention and treatment of a wide range of diseases, from cancer to post-traumatic stress disorder.
On May 23, Lawson hosted a Café Scientifique event where a panel of Lawson Imaging scientists discussed their cutting-edge work. Guests had the opportunity to ask questions as part of an open-forum discussion to gain insights from the speakers, and from one another.
In celebration of Canada’s 150th anniversary as a nation, this event is the first of a two-part series focusing on the future vision for health care in Canada and the legacy that research at Lawson will leave.
Imaging of the heart: Seeing the cause of chest pain more clearly
By Dr. Ting-Yim Lee, Lawson scientist, Medical Physicist at St. Joseph’s, professor at Western University’s Schulich School of Medicine & Dentistry, and scientist at Robarts Research Institute
When patients with chest pain arrive in the emergency department, they are given an electrocardiogram (ECG) and blood test. These diagnostic tests determine if the pain has a non-cardiac cause (such as heart burn), if it is caused by a heart attack, or if the patient has angina (plaque formation in the coronary arteries that either reduces or temporarily cuts off blood flow to the heart) but did not have a heart attack.
If a patient has angina, they are then given additional diagnostic testing to see whether a blood clot has formed and where it is located. This is determined by two different imaging techniques: x-ray imaging (angiogram) and nuclear imaging. This process is invasive and means that patients must be scheduled for two different exam days. Using two techniques also means that there can be image misalignment, and the images often provide poor detail.
Dr. Ting-Yim Lee’s lab has pioneered a Computed Tomography (CT) method for imaging blood flow to the heart muscle (CT Perfusion), which can help patients avoid unnecessary tests and treatment, as well as reduce health care costs.
“CT imaging is a non-invasive imaging technique that uses x-rays to create high-detail cross-sectional images of the body. Using this method, we can evaluate the degree of blockage in coronary arteries – with one diagnostic test instead of two,” says Dr. Lee.
Using light and sound to improve breast surgery
By Dr. Jeffrey Carson, Lawson scientist and associate professor at Western University’s Schulich School of Medicine & Dentistry
“Most women diagnosed with breast cancer undergo surgery, and months of chemotherapy and radiotherapy. They must deal with the discomfort, side-effects, emotional stress and financial burden of treatment. Almost one in four surgeries for breast cancer must be repeated, meaning many women have to go through this all over again,” says Dr. Jeffrey Carson.
In breast conserving surgery, there is a high chance of repeat surgery as the surgeon must see and remove 100 per cent of the tumour in order for it to be successful. They are not able to determine whether the entire tumour was removed until after the surgery has been completed.
Dr. Carson and his team at St. Joseph’s have developed a technology called Intraoperative Photoacoustic Tomography (iPAT), which has the potential to reduce the chance of repeat surgery for breast cancer. The technology is able to image surgery specimens in the operating room during surgery, allowing surgeons to determine whether the whole tumour has been removed before the surgery is complete.
How imaging can improve the management of epilepsy
By Dr. Udunna Anazodo, postdoctoral fellow at Lawson
Most patients with epilepsy are effectively treated with antiepileptic drugs. However, 36 per cent will not respond to the drugs. For these patients, surgery on the area of the brain that is causing seizures is the standard of care – if patients are good surgical candidates.
“If patients with epilepsy are to undergo surgery there must be a good indication of where the seizure focus is and it must be possible to determine that removing this portion of the brain will not affect brain function,” says Dr. Udunna Anazodo.
To see whether they are good candidates for surgery, patients must undergo an invasive procedure called intracranial monitoring, where electrodes are placed on the brain.
Dr. Anazodo has been studying how PET/MRI can be used to map seizures with the goal of minimizing the need for invasive intracranial monitoring. This technique makes it possible to locate areas in the brain that cause seizures and to see if the seizures affect brain functions.
See photos from the event on Lawson’s Facebook page.
Above: Café Scientifique presenters (from left to right): Drs. Jeffrey Carson, Frank Prato (moderator), Ting-Yim Lee and Udunna Anazodo.
