CT exam guide
About the Computed Tomography (CT) exam
The ARRT Computed Tomography examination assesses patient care, CT safety, image production, and cross-sectional procedures. Preparation should integrate contrast decisions, dose optimization, acquisition and reconstruction, artifact correction, anatomy, pathology, and protocol adaptation rather than memorizing isolated settings.
MedPorium is an independent education platform and is not affiliated with or endorsed by The American Registry of Radiologic Technologists (ARRT). Exam details can change; confirm them with the official source before applying.
CT exam format at a glance
- Questions
- 195
- 165 scored; 30 unscored
- Time
- 195 minutes of test time within a 215-minute appointment
- Delivery
- Computer-based testing at Pearson VUE test centers
Knowledge to review for the CT exam
These foundations support the practical tasks in the official examination matrix.
Patient and contrast care
- History, labs, pregnancy, renal risk, allergies, medications, IV access, consent, communication, infection control, monitoring, and emergencies
- Iodinated and enteric contrast properties, dose, timing, administration, extravasation, reactions, and treatment
Safety and image science
- Radiation biology, dose descriptors, reference levels, shielding, optimization, pediatric and pregnancy considerations
- CT system components, helical and axial acquisition, pitch, collimation, detectors, reconstruction, post-processing, artifacts, and quality control
Cross-sectional procedures
- Head, neck, spine, chest, cardiac, abdomen, pelvis, musculoskeletal, vascular, trauma, and special procedures
- Sectional anatomy, pathology, patient positioning, scan range, phases, gating, reformats, angiography, and protocol modification
CT examination matrix
The percentages below are the approximate exam-score weights published by The American Registry of Radiologic Technologists (ARRT). Use them to allocate study time, then adjust for your own weak areas.
12.7%
Patient Care
Assess and prepare patients, administer contrast safely, monitor response, and manage adverse events.
- Review indication, history, pregnancy, labs, renal function, allergies, medications, and prior imaging
- Establish access and administer iodinated or enteric contrast with correct dose, route, rate, timing, and precautions
- Recognize and respond to anxiety, extravasation, allergic-like or physiologic reaction, and medical emergency
12.7%
Safety
Apply radiation protection, dose metrics, optimization, and special-population safeguards.
- Relate deterministic and stochastic effects to CT exposure
- Interpret CTDIvol, DLP, dose reports, reference levels, and dose alerts
- Reduce dose through justification, centering, scan range, kVp, mA modulation, pitch, reconstruction, and patient-specific protocols
31.5%
Image Production
Apply system operation, acquisition, reconstruction, post-processing, quality control, and artifact correction.
- Relate detector, collimation, pitch, rotation, field of view, matrix, slice width, kernel, and iterative reconstruction to image quality
- Perform multiplanar, maximum-intensity, volume-rendered, and other post-processing
- Recognize motion, beam hardening, partial volume, metal, aliasing, ring, and equipment artifacts and correct them
43.1%
Procedures
The largest area applies anatomy, pathology, positioning, protocol design, and phase timing across body systems.
- Select scan range, position, acquisition, contrast phase, and reconstruction for neurologic, thoracic, abdominal, pelvic, musculoskeletal, and vascular studies
- Identify normal and variant cross-sectional anatomy and common pathology
- Adapt protocols for trauma, pediatrics, cardiac imaging, angiography, interventions, implants, and patient limitations
How to use this CT diagnostic
The diagnostic follows the September 2026 specification. Review each miss by decision type: patient or contrast safety, radiation dose, acquisition, reconstruction, quality control, anatomy, pathology, or protocol selection and adaptation.
High-yield CT study priorities
Priority 1
Tie parameters to consequences
For each change in kVp, mA, pitch, rotation, collimation, slice width, kernel, or reconstruction, predict dose, noise, resolution, and artifact effects.
Priority 2
Master contrast timing
Compare noncontrast, arterial, portal venous, delayed, excretory, and multiphase logic by anatomy and clinical question.
Priority 3
Study anatomy in acquisition planes
Review anatomy and pathology on axial images first, then confirm how reformats and angiographic displays change interpretation.
Priority 4
Practise protocol adaptation
Use cases involving size, age, pregnancy, renal impairment, motion, metal, trauma, cardiac rate, poor access, and prior reactions.
CT exam FAQ
How many questions are on the ARRT Computed Tomography examination?
The current examination format contains 195 questions: 165 scored questions and 30 unscored pilot questions. Pilot questions are mixed into the examination and are not identified.
How long is the Computed Tomography examination?
195 minutes of test time within a 215-minute appointment. ARRT's appointment time also includes the tutorial, nondisclosure agreement, and survey where applicable.
How is the content outline weighted?
The currently effective specification is approximately Patient Care 12.7%, Safety 12.7%, Image Production 31.5%, Procedures 43.1%. These percentages are calculated from ARRT's scored-item counts, so rounding may prevent the displayed values from totaling exactly 100%.
What should I prioritize for Computed Tomography?
Procedures is the largest scored content area at approximately 43.1%. Give it the largest share of practice, but continue sampling every area because the examination blueprint is broad.
What score is required to pass an ARRT examination?
ARRT reports examination results on a scaled score from 1 to 99, and a scaled score of 75 is required to pass. A 75 scaled score is not the same as answering 75% of questions correctly.
Does this diagnostic predict whether I will pass?
No. A 15-question diagnostic is a low-confidence baseline, not a validated pass prediction. Review every rationale and use larger mixed and content-specific sets to build a more stable readiness estimate.
Is MedPorium affiliated with ARRT?
No. MedPorium is an independent education platform and is not affiliated with or endorsed by The American Registry of Radiologic Technologists.
Review and official source
Clinical reviewer: T. U. Umbridge
Exam format and matrix information were checked against the ARRT Computed Tomography credential page and examination content specifications. Source reviewed October 15, 2026.
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