 |
|
|
Imaging Services
|
PET and PET/CT
 PET
Positron Emission Tomography (or P.E.T. scan as it is commonly referred) is an imaging technique that relies on changes in tissue biochemistry. Most well known conventional medical imaging techniques, such as X ray, ultrasound, CT and MRI, depend on changes in the anatomy or structure of organs. P.E.T. is able to image changes in cells and tissues often before there are changes in anatomy.
Biologically active natural compounds such as oxygen, carbon and glucose labeled with radioactive isotopes are given intravenously and react in the body identically to their non radioactive counterparts. The normal and abnormal activity (distribution) can be imaged with a P.E.T. scanner. The tracer amounts used do not have a pharmacological effect and there are no known biological or radiation hazards associated with P.E.T. imaging.
The FDA has approved FDG-P.E.T imaging for several cancer related problems. A partial list of these cancer-related problems are presented below:
Evaluation of solitary lung nodules for the presence of cancer
Preoperative staging and re-staging of some lung cancers
Staging and re-staging of lymphomas
Staging and re-staging of malignant melanomas (skin cancers) prior to surgery
Staging and re-staging of colon cancer
Staging and re-staging of breast cancer
Staging of cervical cancer
Staging and restaging of esophageal cancer
Staging and restaging of head and neck cancer
Staging and restaging thyroid cancer
Other cancers, such as liver, pancreas, and soft tissue sarcomas, can be detected and followed with FDG-P.E.T.
PET scans can be done on an outpatient basis. It is also possible that some hospital inpatients may undergo a PET examination for certain conditions. A small amount of radioactive material is injected into the vein 40 ~ 60 minutes before scanning. The patient lies on a table that slides into the middle of the PET scanner for 40 ~ 50 minutes. The scanner detects gamma rays and maps an image of the area, allowing the physician to see the location of the metabolic process. For example, glucose (or sugar, which the body uses to produce energy), combined with a radioisotope, will show where glucose is being used in the brain, the heart muscle, or in a growing tumor. The entire procedure is expected to last from 2 ~ 3 hours, depending on the type of PET examination the patient is undergoing.
In What Conditions are PET Scans Helpful?
Oncology (Tumors): The largest growth area of PET is in the area of tumor evaluation. The information PET provides on the active status of tumors has proven extremely helpful for determining methods of therapy or surgery. Scans performed after treatment will demonstrate the effectiveness of that treatment on the tumor.
Neurology: Many patients with epilepsy do not respond well to drug therapy. When surgical intervention is required, PET can be helpful in locating the exact area of the brain causing the seizures. Imaging the brain with radioactive glucose has also been found useful in diagnosing Alzheimer's Disease and other conditions that may cause memory loss or mental deterioration.
Cardiology: PET is very helpful in determining presence and extent of Coronary Artery Disease. Unnecessary invasive heart catheterizations can often be avoided with cardiac PET imaging due to its increased clarity and sensitivity over cardiac SPECT imaging, which has long been the standard cardiac imaging procedure.
Read More... |
|
|
