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.
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.
Our 10 medical programs are spread across eight hospital sites – Princess Margaret, Toronto General, Toronto Rehab’s five sites, Toronto Western – as well as our education programs through the Michener Institute of Education at UHN. Learn more about the services, programs and amenities offered at each location.
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Find out how to get to and around our nine locations — floor plans, parking, public transit, accessibility services, and shuttle information.
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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.
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A brain aneurysm is a bulge or ballooning of the wall of a blood vessel in the brain. As blood flows through the vessels, it passes by the bulging wall and over time, the pressure can weaken it. Though rare, the steady pressure can cause the aneurysm to rupture. Brain aneurysms affect mostly adults between the ages of 40 to 60, with a higher prevalence in women. The cause of most aneurysms is unknown, although there's evidence they may be inherited.
Our team has many different health care practitioners who can diagnose a brain aneurysm and determine the best course of treatment. The first step is to get a visual picture of your brain, the blood vessels and the aneurysm. After the tests are completed, a member of the team will discuss with you and your family or caregiver your treatment options.
A treatment for an aneurysm depends on a variety of factors, including your age, overall health, if the aneurysm is producing symptoms, and the size, location and shape. Some aneurysms require a single treatment, while others are complicated because of their location, shape or size. They may require more than one treatment type. The health care practitioner will provide your options to you during your clinic visit. The role of treatment is to prevent the risk of a rupture, but keep in mind – the rate of rupture is very low.
An aneurysm that's less than 5 mm in size or one without symptoms is considered too small to treat, and its potential to rupture is extremely unlikely. A periodic test, such as a CT Angiography, may be recommended to check whether it's grown in size.
Endovascular TreatmentThis treatment uses a platinum coil sent through an artery in the groin to the aneurysm to pack it off. Sometimes a wire mesh is placed into the aneurysm to change its shape.
Surgical TreatmentThis kind of treatment includes "clipping" the aneurysm with a small titanium clip that looks like a small set of tweezers. It's placed on the "neck" of the aneurysm or the area where it bubbles out from the artery. If the situation is complicated, the surgeon can create a detour for the blood and a small artery or vein is sewn around the aneurysm.
For more information, please see the videos in the section "Treatment" and click on which video you want to watch.
To watch a video of the procedure, please
The Krembil Brain Institute was the first facility in Canada to perform surgery with a procedure called ELANA (Excimer Laser Assisted Non-occlusive Anastomosis). It uses a laser to treat complex brain aneurysms and blocked arteries to the brain.
The ELANA technique allows neurosurgeons to avoid using regular bypass surgery, which involves clamping an artery to create a new source of blood flow. In the conventional operation, the clamps may have to stay on for a half-hour or even an hour, and that's where the risk comes in – cutting off blood flow to the brain can cause a stroke that may leave permanent damage. This also leaves surgeons with an extremely small window of time to complete the bypass. But by using this revolutionary laser technique, a neurosurgeon can maintain blood flow at all times.
There are a few different tests that can provide the team with the necessary information needed. A health care practitioner may order more than one. Some of these tests can be completed by your family doctor before your first clinic visit.
Your first appointment can take 2 hours or more. We'll review your test results with you and answer all your questions. We may also arrange to have some tests done during your clinic visit, such as a CT Scan. If other tests are needed, we'll discuss them with you at this time, so please remember to bring your questions. Follow-up appointments usually take 15 to 45 minutes. During this visit, we may discuss treatment results and your options. You may meet different members of the team.
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Our team includes:
Patient Care Coordinator: Gail Nixon
Chief of Neuroradiology: Dr. Timo Krings
Medical Imaging Radiologist: Dr. Ronit Agid
Medical Imaging Radiologist: Dr. Richard Farb
Medical Imaging Radiologist: Dr. Vitor Mendes Pereira
Medical Imaging Radiologist: Dr. Robert Willinsky
Neurosurgeon: Dr. Ivan Radovanovic
Vascular Surgeon: Dr. Miranda Witheford
Neurologist: Dr. Joanna Schaafsma
Adult & Practice Lead: Stephanie van Rooy
Clinical Nurse Coordinator, specializing in Neuroradiology
Clinical Research Coordinator
You will be contacted with information about your first appointment.
Please bring the following to your appointment. Not all of these items may be needed for your appointment. Our clinic or your referring doctor will let you know what you must bring.
Please arrive 15 minutes before your appointment.
When you arrive, you will sign in with the receptionist. You will need your health card (OHIP card) to sign-in. If you do not have an OHIP card, please bring another form of government-issued photo ID, such as a driver’s license or passport.
You may be given a Measuring Health Equity Questionnaire to fill out. This form contains questions about your background. We collect this information to find out who we serve and what unique needs you may have. The form is voluntary and you can choose ‘prefer not to answer’ to any or all questions. However, the information you choose to give us will help us improve the quality of care for you and others.
First appointments take longer than follow-up appointments. Your first appointment can take 2 hours or more. Follow-up appointments usually take 15 to 30 minutes. We do everything we can to stay on time but sometimes unforeseen circumstances may delay your appointment.
At the end of your first appointment, the nurse or doctor will give you a contact list for your health care team. If you don’t get a contact list, feel free to ask for it.
After every appointment, a member of your health care team will tell you about your next visit. Be sure you understand what is going to happen next. For example, know the time and place of your next visit or if someone will call you with this information.
If you are unsure about what your next steps are, don’t be afraid to ask a member of your team. We are here to help you.
We understand that reaching us by phone can sometimes be difficult. Often our phone lines are busy or are turned over to the message centre so our staff can prepare for clinic visits or help other patients. We make every effort to return your call within 24 hours. Our staff will try to reach you 2 times. If we are not able to reach you directly you may need to call us again.