PET scan: Definition purpose, side effect, procedure, Advantage, Disadvantage | Radiology Buzz

(PET SCAN) POSITRON EMISSION TOMOGRAPHY

Introduction 

An imaging modality which gives better functional and morphological information in combination with CT and MRI.

Used radioactive traces such FDG (Fluorodeoxyglucose)as  it is either injected into the blood stream, inhaled or swallowed.

Fig.1   PET SCAN MACHINE

It is a non invasive technique.

Past of nuclear medicine scan.

Provides metabolic information of neoplastic processes but is not specific for neoplastic processes.

It accumulation in physiologically active areas in various organs including brain, muscles, salivary glands, myocardium, GIT, brown adipose tissue, thyroid gland & gonads.

Why PET Scan are used?

The glucose in FDG is taken up by these active tissue for metabolism which in turn carries the radioactive traces tagged with the glucose.

Advantage of Positron Emission Tomography

Ability to study body function through biochemical functions. i.e., it is able to detect disease before changes in the anatomy becomes apparent making it more effective in diagnosing then other imaging test.

Fig.2   PET Scan

Can be used as an alternative to biopsy and other exploratory surgeries to determine how much a disease has spread.

Its ability to distinguish between benign (non-cancerous) and malignant tool that can reduce the number of unnecessary surgeries performed due to  diagnosis and staging data.

Effective used to diagnose early stage of neurological illness such as epilepsy, Alzheimer's disease and other dementia.

Disadvantage of Positron Emission Tomography

Does not provide anatomical details. 

Large number of false positive and false negative results.

Difficult to differentiate the lesions from areas of normal physiological uptake.

Radioactive substance used may not be suitable for patients who are pregnant, suspect they are pregnant or are breast feeding.

The radioactive exposure in PET imaging means that there is only a limited amount of times a patient can undergo this procedure.

PET scan requires cyclotrons, an expensive machine that creates the radioisotopes that are used in the radioactive traces required for PET imaging.

Allergic reaction to traces.

Share: