ARRT Bone Densitometry study guide
ARRT Bone Densitometry · Work through your exam, one topic at a time.
Bone Densitometry is one of ARRT's postprimary credentials. ARRT states its purpose as recognizing individuals who are qualified to perform the role of a Bone Densitometrist-technologists who create images with specialized X-ray equipment so that clinicians can verify low bone density, osteoporosis, or subtle bone loss before recommending treatment such as medication or lifestyle change. Because it is a postprimary discipline, candidates must already hold ARRT certification and registration in an approved supporting discipline; ARRT notes that a supporting credential may in some cases come from another organization, and that holders of a Nuclear Medicine Technology credential from the NMTCB can submit an online account access form to get started. The examination samples four content areas: equipment and instrumentation, patient care and education, image acquisition and analysis, and quality control and data management. The ARRT Bone Densitometry study guide has 4 sections and about 1,079 words.
01Equipment and Instrumentation
DXA measures areal bone mineral density (BMD, g/cm²) by passing two photon spectra through tissue and solving the attenuation equations for soft tissue and bone. Systems either switch kVp or filter the beam with a K-edge filter (cerium or samarium) to create low- and high-energy components; the low-energy beam is preferentially absorbed by calcium hydroxyapatite.
279 words, about 1 min02Patient Care and Education
Ask about pregnancy, recent contrast or nuclear medicine studies, and metal in the region of interest. DXA is very low dose (roughly 1–10 µSv, comparable to a few days of background radiation); pregnancy is not an absolute contraindication, but scan only when justified.
285 words, about 1 min03Image Acquisition and Analysis
Spine: supine, centered on the table, knees flexed over a foam block to flatten lumbar lordosis; scan approximately T12–L5. Hip: supine with the foot secured in the positioning device and the leg in 15–25° internal rotation so the femoral neck lies parallel to the table; include the ischium.
250 words, about 1 min04Quality Control and Data Management
Scan the manufacturer's phantom daily , before patients, and plot results on a control chart. Investigate values beyond ±2 SD or a sustained trend.
265 words, about 1 min