Advisory: Give yourself extra time when travelling by car to Toronto General Hospital, Princess Margaret Cancer Centre, or Toronto Rehab University Centre. City of Toronto construction on University Ave. may cause delays.
At UHN, we strive to deliver Compassionate Care & Caring. Learn more about the services and supports that are available to you throughout your journey.
Our UHN programs and services are among the most advanced in the world. We have grouped our physicians,
staff, services and resources into 10 medical programs to meet the needs of our patients and help us make
the most of our resources.
At the heart of everything we do at UHN are our Healthcare Professionals. Refer a patient to one of our 12 medical programs. Learn more about the resources and opportunities available for professional growth.
University Health Network has grown to be one of the largest research and teaching hospital networks in Canada - pioneers in improving the lives of patients. Our long history of health professions education at Toronto General, Toronto Western, Princess Margaret and Toronto Rehab hospitals has consistently advanced the science of education.
University Health Network is a health care and medical research organization in
Toronto, Ontario, Canada. The scope of research and complexity of cases at UHN has made us a national and international
source for discovery, education and patient care.
Being touched by illness affects us in different ways. Many people want to give back to the community
and help others. At UHN, we welcome your contribution and offer different ways you can help so you can find one that suits you.
The Newsroom is the source for media looking for information about UHN or trying to connect with one
of our experts for an interview. It's also the place to find UHN media policies and catch up on our news stories, videos, media releases,
podcasts and more.
This mannequin’s oral cavity was fitted with a latex balloon filled with compressed oxygen and dye to simulate a patient’s cough during an eye examination
In the early days of the COVID-19 pandemic, the ophthalmology community had one pressing question: How can we keep everyone safe, when our practice involves such close contact?
"In ophthalmology, we can't really maintain any distance from patients because our exams are right in front of their faces," explains Dr. Efrem Mandelcorn, a retinal surgeon and clinician investigator at the Donald K. Johnson Eye Institute's Retina Clinic and Sprott Department of Surgery at UHN.
To determine how to lessen viral exposure, Dr. Mandelcorn and a team of his colleagues created a series of experiments that quickly had significant, real-world impact.
The team placed a small latex balloon filled with compressed oxygen and fluorescent dye inside a mannequin's oral cavity. The unmasked mannequin was placed in the patient's position in front of a slit-lamp, the instrument routinely used during eye examinations. A live examiner donned personal protective equipment and took their place opposite the mannequin. When the balloon burst, it simulated a cough from a patient by ejecting dye droplets. The spray, picked up under ultraviolet light, covered the examiner's upper body and equipment.
However, when the mannequin wore various types of masks, including cloth, surgical and N95 varieties, the spread either decreased or disappeared entirely. Findings suggested that wearing a well-fitting cloth mask properly is more effective than wearing a surgical mask incorrectly. And N95 masks are the most effective of all.
Although Dr. Mandelcorn is no stranger to publishing innovative retina research, the reaction to this COVID-19-inspired paper caught him by surprise. The video he posted of the experiments has been watched more than 80,000 times. "In my little world," he says, "it went viral, pardon the pun."