Preparing for the ARRT CT post-primary certification examination takes focused, targeted study. Our free computed tomography practice test PDF gives you realistic multiple-choice questions covering all major content areas tested on the actual exam — so you can practice anywhere, on paper, at your own pace.
Download the printable PDF below, work through every question, and use the answer key to identify gaps in your knowledge before exam day. Whether you're a radiologic technologist pursuing CT specialty certification for the first time or refreshing after years in the field, this resource is built around the official ARRT CT examination specifications.
The ARRT CT examination is a post-primary credential, meaning candidates must already hold primary ARRT certification — typically in radiography, nuclear medicine, or radiation therapy — and must document clinical experience in computed tomography. You need to log a minimum number of CT procedures across required categories before sitting for the exam. The written exam consists of 165 questions (150 scored, 15 pretest), and passing requires a scaled score of 75 or higher.
A significant portion of the exam addresses patient care responsibilities unique to CT. This includes informed consent procedures, patient positioning and immobilization, screening for contrast contraindications (renal function, metformin use, allergy history), and managing adverse reactions ranging from mild urticaria to anaphylaxis. You must know pre-medication protocols for patients with prior contrast reactions and the proper timing for steroid regimens.
Radiation dose management is tested heavily. Understand CT Dose Index (CTDI), dose-length product (DLP), and effective dose. Know how scan parameters — kVp, mAs, pitch, slice thickness, rotation time — affect dose and image quality. Automatic exposure control (AEC/tube current modulation) and iterative reconstruction reduce dose without sacrificing diagnostic quality. ALARA principles apply to all patient populations, with special attention to pediatric protocols and pregnant patients.
Expect questions on helical (spiral) acquisition geometry, including how pitch is calculated and how it affects dose and image quality. Single-detector CT vs. multi-detector CT (MDCT) configurations are fair game, as are slip-ring technology, detector efficiency, and the relationship between collimation, reconstruction interval, and image overlap. Understand the difference between axial, helical, and dynamic (perfusion) scanning modes.
Filtered back-projection (FBP) has been the standard reconstruction method for decades. It is fast but amplifies image noise at low-dose settings. Iterative reconstruction algorithms — including adaptive statistical iterative reconstruction (ASIR), model-based iterative reconstruction (MBIR), and vendor-specific variants — apply repeated mathematical modeling to reduce noise and artifact while preserving resolution. Know the trade-offs: iterative methods allow lower-dose protocols but require more processing time.
Iodinated contrast agents are central to most CT protocols. Understand ionic vs. non-ionic agents, osmolality differences, and why low-osmolar non-ionic agents are preferred. Contraindications include severe renal impairment (eGFR thresholds), prior severe contrast reaction, and certain thyroid conditions. For patients on metformin, know the hold protocol. Injection rates, volumes, and scan timing (arterial phase, portal venous phase, delayed phase) are tested within specific body-region protocols.
The X-ray tube in CT operates continuously during helical acquisition, placing high thermal demands on the anode. Heat units (HU) and heat capacity ratings determine how many consecutive scans can be performed. Detector arrays in modern MDCT systems may have 64, 128, 256, or 320 rows, enabling rapid volumetric coverage. The gantry houses the rotating tube and detector assembly; gantry tilt is used in specific protocols such as inner ear and facial bone CT. Reconstruction algorithms run on dedicated image processing hardware to generate axial, coronal, sagittal, and 3D volume renderings.
You must recognize normal anatomy and common pathology on axial, coronal, and sagittal CT images across all body regions. Brain CT: identify ventricles, basal ganglia, internal capsule, cerebellum. Chest CT: lobar anatomy, mediastinal structures, great vessels. Abdominal CT: liver segments, biliary system, pancreatic head/body/tail, spleen, adrenal glands, kidneys. Pelvic CT: bladder, uterus/ovaries or prostate, iliac vessels. Spine CT: vertebral body morphology, disc spaces, neural foramina, facet joints.
Window width (WW) and window level (WL) settings determine how Hounsfield units are displayed. Know the standard settings: brain (WW 80, WL 40), lung (WW 1500, WL -600), bone (WW 2000, WL 300), soft tissue (WW 400, WL 40). Maximum intensity projection (MIP), minimum intensity projection (MinIP), and volume rendering (VR) are post-processing techniques tested in the context of vascular, airway, and musculoskeletal applications.
After working through the PDF, reinforce your knowledge with interactive online questions. Our computed tomography practice test covers the same ARRT CT content areas with immediate feedback, detailed explanations, and score tracking so you can monitor your progress and focus your remaining study time where it counts most.