Avenue Radiologists, PC has installed the latest generation
multidetector PET/CT Sytem with the highest resolution of PET configuration,
to allow for imaging virtually all organ systems, including
Positron Emission Tomography
(PET) and Computerized Tomography (CT) are both standard imaging
tools that allow physicians to pinpoint the location of cancer
within the body before making treatment recommendations.
The highly sensitive PET scan detects the metabolic signal of
actively growing cancer cells in the body and the CT scan provides
a detailed picture of the internal anatomy that reveals the location,
size and shape of abnormal cancerous growths.
Alone, each imaging test has particular benefits and limitations
but when the results of PET and CT scans are "fused" together,
the combined image provides complete information on cancer
location and metabolism.
The bottom line is that you can have both scans - PET and CT
- done at the same time.
What is PET/CT?
In one continuous full-body scan (usually about 30 minutes),
PET captures images of miniscule changes in the body's metabolism
caused by the growth of abnormal cells, while CT images simultaneously
allow physicians to pinpoint the exact location, size and shape
of the diseased tissue or tumor.
Essentially, small lesions or tumors are detected with PET
and then precisely located with CT.
How PET/CT Works
a CT scan provides anatomical detail (size and location of
the tumor, mass, etc.), a PET scan provides metabolic detail
(cellular activity of the tumor, mass, etc.). Combining these
two scanner technologies makes a PET/CT superior to either
technology alone. 1
Anatomical: CT scanners send x-rays through
the body, which are then measured by detectors in the CT scanner.
A computer algorithm then processes those measurements to produce
pictures of the body's internal structures.
Metabolic: PET images begin with an injection
of a solution of glucose (sugar) that has been "tagged" with a radioactive
chemical isotope (generally fluorine 18, or FDG). Metabolically
active organs or tumors consume sugar at high rates, and as the
tagged sugar starts to decay, it emits positrons. These positrons
then collide with electrons, giving off gamma rays, and a computer
converts the gamma rays into images. These images indicate metabolic "hot
spots," often indicating rapidly growing tumors (because
cancerous cells generally consume more sugar/energy than other
The entire examination usually takes less than 30 minutes,
providing comprehensive diagnostic information to your health
care team very quickly. The PET/CT system provides exceptional
image quality and accuracy of diagnostic information.
1 Zerhouni, E., M.D., Johns Hopkins Hospital (2001,
Benefits of PET/CT
There are tremendous benefits of having a combined PET/CT scan:
With the high-tech images that
the PET/CT scanner provides, patients are given a better chance
at a good outcome and avoid
unnecessary procedures. A PET/CT image also provides early detection
of the recurrence of cancer, revealing tumors that might otherwise
be obscured by scar tissue that results from surgery and radiation
therapy, particularly in the head and neck.1
In the past, difficulties arose from trying to interpret the
results of a CT scan done at a different time and location than
a PET scan, due to the fact that the patient's body position
had changed. The combination PET/CT provides physicians a more
complete picture of what is occurring in the body - both anatomically
and metabolically - at the same time.2
Shreve, P., M.D., University of Michigan Health System, (2002,
Hricak, H., M.D., Memorial Sloan Kettering Cancer Center, (2002,