Everything you need to plan your ARDMS registry, from who can apply and what each exam covers to free practice questions, physics flashcards and live coaching with Dr Abdullah.
Figures from Inteleos, the organisation that runs ARDMS. Fees and formats can change, so check the official exam pages before you apply.
2 hours · US$275
3 hours · US$300 · includes image hotspots
Scaled score from 300 to 700 · pass/fail
To pass SPI and a specialty, in either order
Every ARDMS credential is earned by passing SPI once and then at least one specialty exam. Passing SPI also lets you add more specialties later without retaking physics, as long as your status remains active.
Registered Diagnostic Medical Sonographer
Registered Diagnostic Cardiac Sonographer
Registered Vascular Technologist
Registered Musculoskeletal Sonographer
Most candidates start with SPI + Abdomen or SPI + OB/GYN, the two most common routes to RDMS.
You must meet one prerequisite before ARDMS approves you to sit an exam. This is a simplified summary of the current Inteleos prerequisites document.
The most relevant route for doctors in Pakistan. You need a current medical licence or registration (the prerequisite accepts one from any country, e.g. PMDC), 500 diagnostic studies in the specialty over six months, an experience letter and a signed Clinical Verification (CV) form.
A bachelor's degree in any subject plus 12 months of full-time clinical ultrasound (at least 1,680 hours). Foreign degrees need a course-by-course credential evaluation.
Graduates of a CAAHEP or equivalent accredited sonography programme. Clinical experience is covered by the programme.
Students who have passed a physics course, or earned 12 ARDMS-accepted CME credits, can sit SPI only before graduating.
Other pathways exist, for allied health graduates and holders of CCI, ARRT or Sonography Canada credentials. Volunteer, unpaid and 3D/4D-only scanning does not count as clinical experience. Prerequisites change, so always confirm on the Inteleos website before you pay.
| Area | Focus on |
|---|---|
| Ultrasound physics | Wave parameters, propagation, attenuation, impedance, reflection |
| Clinical safety | Bioeffects, thermal and mechanical index, ALARA |
| Quality assurance | Phantoms, QA testing, preventive maintenance |
| Instrumentation | Pulser, receiver functions, storage, display |
| Transducers | Piezoelectric effect, arrays, focusing, care and cleaning |
| Image optimisation | Gain, TGC, focus, artifacts |
| Doppler | Doppler equation, spectral, colour, power, aliasing, haemodynamics |
| Area | Focus on |
|---|---|
| Anatomy | Liver segments, biliary tree, pancreas, kidneys, spleen, vessels |
| Perfusion & function | Normal Doppler waveforms, lab values, physiology |
| Pathology | Focal liver lesions, gallbladder disease, renal masses, aorta |
| Vascular abnormalities | Portal hypertension, thrombosis, aneurysm, TIPS |
| Trauma & post-op | FAST, collections, transplants, post-surgical anatomy |
| Abdominal physics & care | Technique, patient care, infection control |
Original practice questions written for Radiology Boards. Pick an answer to see the explanation straight away.
Tap a card to flip it. These are the formulas and numbers that come up again and again on the SPI.
For working sonographers and doctors studying about 1–2 hours a day. Do SPI first, because physics underpins every specialty exam.
| Week | Topic | Goal |
|---|---|---|
| Week 1 | Sound waves, parameters, propagation | Derive every formula yourself; master the 13 µs rule |
| Week 2 | Transducers, beams, resolution | Explain axial vs lateral vs elevational vs temporal resolution |
| Week 3 | Instrumentation, artifacts, QA, bioeffects | Recognise every common artifact from a description |
| Week 4 | Doppler & haemodynamics + SPI mock | Timed 110-question mock, then book SPI |
| Week 5 | Liver, biliary, pancreas | Normal measurements and classic pathology appearances |
| Week 6 | Kidneys, adrenals, spleen, retroperitoneum | Renal masses, hydronephrosis, transplant Doppler |
| Week 7 | Vessels, GI tract, paediatric abdomen, trauma | Portal hypertension, aorta, pyloric stenosis, FAST |
| Week 8 | Abdomen mocks & weak areas | Two timed 165-question mocks; re-do every wrong answer |
Dr Abdullah teaches ARDMS preparation for doctors and sonographers. Classes focus on understanding physics rather than memorising it, exam-style practice and help with the application paperwork.
ARDMS (American Registry for Diagnostic Medical Sonography) awards the RDMS, RDCS, RVT and RMSKS sonography credentials. It is part of Inteleos, which now runs applications and exams through its own portal.
You need the Sonography Principles and Instrumentation (SPI) physics exam plus at least one RDMS specialty exam: Abdomen, Obstetrics & Gynecology, Breast, Pediatric Sonography or Fetal Echocardiography. SPI and the specialty must be passed within five years of each other, in either order.
The SPI exam has approximately 110 multiple-choice questions in two hours. The fee listed by Inteleos is US$275, and the passing score is 555 on a 300–700 scale.
The Abdomen (AB) exam has approximately 165 questions over three hours, including image-based hotspot questions. The fee listed by Inteleos is US$300.
Yes. ARDMS has a Physician prerequisite for MD, DO or MBBS holders. It requires a current medical licence or registration from any country, an experience letter and a signed Clinical Verification form, showing 500 diagnostic studies in the specialty over six months. Always confirm the current prerequisites with Inteleos before applying.
You can reapply three days after the attempt, but you must wait 60 days before you can sit the same exam again.
ARDMS exams are delivered by Pearson VUE at test centres in the US, Canada and selected international sites. Use the Pearson VUE test-centre locator to find the nearest centre.
ARDMS® and Inteleos® are trademarks of their respective owners. Radiology Boards is an independent education provider and is not affiliated with or endorsed by ARDMS or Inteleos. Exam facts are summarised from official Inteleos pages as of October 2026. Always confirm details at inteleos.org.