PET scans can reveal changes at the cellular level, while CT scans showed changes in the overall structure of the organ or tissue.
Because of this ability PET scans can detect the disease at an early stage that can not be done by regular CT scan.
PET Scan
PET stands for "positron emission tomography". Scanning (scan) uses a small amount of radioactive material is inserted in the body by injected, snorted, or swallowed.
PET scan will show where the radioactive material accumulates to detect problems with blood flow, oxygen utilization, and metabolism.
CT Scan
CT stands for "computerized tomography" (also referred to as a CAT scan). CT scans use X-rays to obtain cross-sectional images the body.
These images can be viewed individually (two-dimensional) or combined to produce a three-dimensional view.
function
PET scans were able to detect the spread of cancer, identify heart problems, and examine brain disorders, and nervous system.
While CT scans can quickly identify injuries due to accidents and other trauma, evaluate the condition of the patient after surgery and chemotherapy, as well as the detection of cancer and vascular disease.
effect
PET and CT scan is a procedure that has been used for decades and proven to have minimal side effects.
Still, there are a few things to note. Both types of scanning involves the use of radiation.
CT scans may slightly increase the risk of cancer development. However, this risk is very small compared with the benefits of CT scan itself.