A PET‑CT whole body with contrast is a combined imaging test that maps metabolic activity (PET) and detailed anatomy (CT) across the entire body using an injected radioactive tracer and iodinated intravenous contrast. It helps detect, stage, and monitor cancers, infections, and inflammatory disease. The scan takes about 30–90 minutes; risks include radiation exposure and rare contrast reactions, so hydration and allergy screening are performed.

A full-body CT scan with intravenous contrast provides detailed cross-sectional images highlighting organs, blood vessels and soft tissues. It detects tumors, metastases, abscesses, infections, inflammation, internal bleeding, vascular problems (aneurysm, dissection, clots) and major fractures, and evaluates lymph nodes and organ perfusion. Contrast improves distinction between structures and helps characterize masses and abnormal blood flow.

A PET scan for epilepsy is an imaging test that maps brain metabolism using a small radioactive tracer to identify areas with reduced or increased activity. It helps localize seizure foci when MRI or EEG are inconclusive, guiding treatment decisions such as surgery or targeted therapies. Scans are performed interictally or ictally depending on the clinical question and complement other diagnostic tests.

A full-body PET scan can detect many cancers by highlighting areas of abnormal metabolic activity (usually with FDG), making it useful for diagnosis, staging, and finding metastases. However, it can miss small lesions or low‑metabolism cancers (some prostate, neuroendocrine, and certain low‑grade tumours) and can give false positives from inflammation or infection. PET findings usually need correlation with other imaging, biopsy, and clinical assessment.

PET scans involve exposure to ionizing radiation, slightly increasing lifetime cancer risk. Other risks include mild allergic reactions or pain/bruising at the injection site, false positives or negatives, and anxiety or claustrophobia during imaging. They’re generally avoided in pregnancy and may require temporary breastfeeding interruption. High blood glucose can affect accuracy. If combined with CT contrast, rare kidney effects or contrast reactions may occur.

A full-body PET‑CT typically requires about 20–40 minutes of actual scanning. Because a radioactive tracer is injected and needs roughly 60 minutes to accumulate, the overall appointment usually lasts longer. Including injection, uptake, positioning and post-scan checks, expect about 1.5–3 hours from arrival to discharge. Exact times vary by facility and the clinical protocol.