UHN is world leader in 320-slice CT
TORONTO – University Health Network
(UHN) became the first institution in the world to have three 320-slice
CT scanners, as Toronto Western Hospital’s (TWH) scanner began clinical
Considered to be the world’s most advanced Computer Tomography
technology, the 320-slice CT can cut time-to-treatment by two-thirds for
stroke patients, help cancer specialists map tumours for treatment in
greater detail than ever before, and allow cardiac disease to be
diagnosed with unparalleled confidence.
“We have always been pioneers and early adopters of cutting edge CT
technology,” says Dr. Patrice Bret, Radiologist-in-Chief at UHN.
“Embracing this technology represents the next step in a continuum of
Compared to traditional 64-slice CT technology, with an imaging area of
3.2 cm, the 320-slice CT covers 16 cm of anatomy, an area large enough
to capture a full image of an organ and can show blood flow through
specific areas of the body. Images are captured in 0.35 seconds with
just one rotation of the scanner.
Stroke identification at Toronto Western Hospital
At Toronto Western Hospital, the 320-slice CT is located in the
emergency department, the only installation of its kind in the world. In
an environment where every second counts, the speed of the scanner
greatly benefits patients with serious trauma and those exhibiting signs
“Installing this machine in the emergency department will allow us to
more accurately triage patients,” says Dr. Karel Terbrugge, Medical
Imaging Site Director at TWH. “We felt very strongly that emergency
patients should have access to this technology.”
For stroke patients, the new CT will lower time-to-diagnosis from
approximately one hour to about 20 minutes. “We can now very quickly get
a complete image of the brain and assess if a patient will benefit from
revascularization treatment for stroke,” says Dr. Terbrugge. The length
of time between the occurrence of a stroke and receiving treatment is
directly related to the amount of damage to the brain.
Dr. Terbrugge is leading an international research study involving 10
teaching hospitals that will evaluate the medical outcomes of stroke
patients triaged with the 320-slice CT, compared to historical data on
outcomes of patients triaged using traditional MRI technology.
Cancer treatment mapping at Princess Margaret Hospital
At Princess Margaret Hospital (PMH), the 320-slice CT will be used to
target tumours for radiation therapy treatment with greater accuracy.
“The 320-slice CT will allow us to measure breathing-induced motion of
both tumours and normal tissues within the patient,” says Dr. David
Jaffray, Head of Radiation Physics at PMH. “With this information, we
can accommodate for movement and develop highly precise radiation
treatments that induce minimal side-effects.”
The 320-slice scanner also offers new knowledge about the nature of
blood flow through cancerous tissue. Combined with the high-quality
images produced by the scanner, radiation oncologists will be better
able to determine the appropriate level of radiation for treatment and
assess a patient’s response to therapy. “If you think of a tumor as a
city and blood flow as traffic, the complexity of the roads entering the
city results in a slowing of traffic. This technology allows us to see
subtle delays in blood flow and thereby get a representation of the size
of the tumour,” says Dr. Jaffray.
Cardiac diagnostics at Toronto General Hospital
In 2007, UHN’s first 320-slice CT went into operation at the Peter Munk
Cardiac Centre located at the Toronto General Hospital (TGH) and at the
time, was one of only five in the world.
Since then, radiologists at TGH have seen significant radiation dose
reduction for cardiac patients and are better able to diagnose cardiac
disease, because a complete image of the heart can be captured in less
than one second. “Breathing artifact, which causes image blurring, has
been reduced with the 320-slice CT. This means that we have better
diagnostic confidence,” says Dr. Narinder Paul, Medical Imaging Site
Director at TGH. “We’re at the point where we can start to look past
anatomy and start to look at organ perfusion.”
Through the use of the 320-slice CT, radiologists at UHN hope to open
the field for new applications of the technology, such as examining
brain perfusion, the prevention of cardiac disease, and surgical
About University Health Network
University Health Network consists of Toronto General, Toronto Western
and Princess Margaret Hospitals. The scope of research and complexity of
cases at University Health Network has made it a national and
international source for discovery, education and patient care. It has
the largest hospital-based research program in Canada, with major
research in cardiology, transplantation, neurosciences, oncology,
surgical innovation, infectious diseases, and genomic medicine.
University Health Network is a research hospital affiliated with the
University of Toronto.