SPI case studies
SPI · Put your knowledge to work in context.
The Sonography Principles and Instrumentation (SPI) examination is the physics-and-instrumentation exam within the Inteleos/ARDMS certification family. It is aimed at sonographers, vascular technologists, and physicians who need to demonstrate that they understand how ultrasound equipment generates, displays, and measures information - not anatomy or pathology. Content generally centers on the behavior of sound in tissue, transducer construction and selection, beam formation and focusing, signal processing and image display, axial and lateral resolution, artifacts, Doppler principles and hemodynamics, bioeffects, and quality assurance and instrument safety. Because the official exam page could not be retrieved when this material was compiled (the address returned a 404 error page), verifiable logistics such as item count, time limit, fee, passing standard, retake rules, and published domain weights are not stated here; confirm them on the current official Inteleos/ARDMS page before you register. The SPI case studies are 5 cases and about 3,223 words.
1Resolving a 2 mm Aortic Plaque at 12 cm
An abdominal survey must reach the aorta at 12 cm in a patient whose body habitus limits useful penetration to about 14 cm. Your cart has three probes: a 2.5 MHz curved array, a 5 MHz curved array, and a 4 MHz linear array.
622 words, about 3 min2Aliasing in a High-Velocity ICA
Carotid duplex is performed on a 68-year-old with a bruit. Continuous-wave Doppler of the left ICA gives a peak systolic velocity of 1.9 m/s.
696 words, about 3 min3Annual QA: Is the System or the Phantom Wrong?
During annual quality assurance, a curved array is tested on a tissue-equivalent phantom. The phantom's material has a measured speed of sound of 1520 m/s, while the scanner assumes 1540 m/s.
593 words, about 3 min4First-Trimester Color Doppler and the Output Display
A 9-week transabdominal scan is being performed to assess adnexal pain. Color Doppler over a large box has been running intermittently for about 90 seconds at 100 percent output with a 5 MHz curved array.
650 words, about 3 min5Two Extra Echoes That Should Not Be There
A pelvic scan is performed through a full bladder with a 3.5 MHz curved array. A bright linear reflector is seen at 2.8 cm, attributed to the anterior bladder wall and rectus sheath.
662 words, about 3 min