In one continuous scan, PET captures images of miniscule changes in the body's metabolism cased by the changes in cells, while CT images simultaneously allow physicians to pinpoint the exact location, size, and shape of the diseased tissue. Essentially, small cellular changes are detected with PET and then precisely located with CT. Combining these two scanner technologies makes PET/CT superior to either technology alone.
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 organs or tumors).
Procedure
The actual scan usually takes less than 30minutes, providing comprehensivediagnostic information to your health care team very quickly. However,the complete exam process can take up to 3 hours (do to contrastadministration). ThePET/CT system provides exceptional image quality and accuracy ofdiagnostic information.
Preparation for the Exam
The preparation for your PET/CT exam will be given to you at the time your appointment is scheduled.
Please allow up to three hours for your entire visit, including preparation for the exam and time in the scanner. Upon your arrival, a technologist will escort you to the imaging area and administer a very small amount of radioactive glucose. Following the injection, you will rest in a private room for 60 to 90 minutes while the glucose distributes through your body. The scanning procedure is performed while you lie comfortably on the scanner bed.
After the Procedure
The PET exam itself causes no side effects and you will be permitted to drive yourself home. However, if you request a mild sedative be given to you to relieve anxiety, you must have someone available to drive you home.
Post Exam
Before you leave, your results are reviewed inorder to ensure that adequate images were captured. The radiologistwill then interpret the images and send a dictated report to yourdoctor. Your doctor will discuss the results with you.
PET/CT Location
Sacred Heart Center