A full‑body CT scan images the chest, abdomen, pelvis and skeleton to detect acute injuries and structural abnormalities: internal bleeding, organ lacerations, bone fractures, vascular injuries, aneurysms, lung problems (including pulmonary embolism), tumors or metastases, abscesses, and kidney or gallstones. It’s excellent for trauma assessment and staging of disease but may miss very small or early lesions and involves radiation exposure.

A whole‑body CT scan’s imaging time is brief—typically 5–30 minutes of actual scanning. If IV contrast is used, add 15–60 minutes for injection, circulation and monitoring. Allow extra time for registration, positioning and verbal instructions, so the entire appointment commonly takes about 30–90 minutes from arrival to discharge. Emergency trauma protocols may be faster; outpatient studies can require more prep.

Whole-body CT typically includes non-contrast and contrast-enhanced scans covering the head, neck, chest, abdomen and pelvis, often extended to the spine, major blood vessels and extremity joints as needed. Protocols use arterial and venous phase imaging, thin-slice reconstructions and 3D reformats. It assesses trauma, bleeding, fractures, organ injuries, vascular lesions and tumor spread; contrast is commonly used.

A CT scan itself rarely causes a migraine. Some people may get headaches afterward from contrast agents, anxiety, positioning, or scanner noise/brightness. Iodinated contrast can rarely provoke headache as part of a contrast reaction or neurotoxicity. If you have migraine history the procedure may trigger an attack. New, severe, or worsening headaches after a scan should be reported promptly to your clinician.

Whole-body CT involves substantial ionizing radiation and is not recommended for routine screening in healthy people because cumulative exposure raises a small but real cancer risk and can produce false positives. It’s valuable for trauma, staging or specific clinical problems. Contrast can cause allergic reactions or kidney injury. Discuss benefits, risks and alternatives (MRI, ultrasound) with your clinician.

CT is faster, widely available and best for bone fractures, acute bleeding, chest and trauma imaging; it uses ionizing radiation. MRI gives superior soft‑tissue contrast for brain, spinal cord, joints and tumors without radiation, but is slower, costlier and may be unsafe with some metal implants or for claustrophobic patients. Choice depends on the clinical question, urgency, patient factors and contraindications.