A CT scan acquires multiple thin cross-sectional X-ray images of the body, showing internal anatomy slice by slice. A 3D CT is created by reconstructing these slices into a volumetric, three-dimensional model for clearer spatial visualization. 3D reconstructions aid surgical planning, fracture assessment, and implant sizing. Radiation dose and scan acquisition are generally similar; 3D rendering is post-processing.

A shoulder CT provides detailed images of bone structures: the humeral head, glenoid, clavicle, scapula and acromion. It detects fractures, dislocations, bone fragments, joint alignment, bone spurs, degenerative changes and tumors or cysts. CT arthrography can better outline cartilage and labral tears, but CT is less sensitive than MRI for rotator cuff and other soft-tissue injuries.

A 3D CT scan appointment typically takes 10–30 minutes. The actual image acquisition often lasts seconds to a few minutes, but positioning and setup add time. If intravenous contrast is used, expect extra time for injection and brief monitoring (often 30–60 minutes total). Computer reconstruction for 3D images usually adds only a few minutes before study review.

3D CT scans expose you to ionizing radiation, slightly increasing lifetime cancer risk; the dose is low but cumulative scans raise concern. If iodinated contrast is used, possible reactions include nausea, rash, itching, breathing difficulty and, rarely, kidney injury. Other issues: discomfort, claustrophobia, and rare injection-site bruising. Pregnant people are usually advised to avoid CT unless essential.

A 3D CT scan is done with the patient lying on a motorized table that moves through a rotating X‑ray gantry while multiple thin cross‑sectional images are rapidly acquired. IV or oral contrast may be given to highlight structures and brief breath‑holds are sometimes required. A computer reconstructs the slices into detailed 3D images for physician review. The procedure is noninvasive, quick, and uses ionizing radiation.

Three CT scans are usually safe when medically justified: the added radiation gives a small increase in lifetime cancer risk that depends on scan type, dose, age and timing. For adults the risk is generally low and benefits often outweigh harms; for children or pregnant people sensitivity is higher. Always discuss necessity, alternatives and dose‑reduction options with your clinician.