Incidental findings or diagnoses with Dual-Energy X-Ray Absorptiometry

Objectives: Nowadays a lot of emphasis is given to incidental findings discovered during imaging or other diagnostic examinations. DXA is sometimes forgotten to belong to the same family of conventional imaging techniques. Besides, new DXA technologies provide improved spatial resolution and high image quality. Our purpose was to review DXA examinations to detect collateral findings that might be reported or not and to highlight the possible impact on patient healthcare. Moreover a wide analysis of incurred pitfalls was performed. Materials/Methods: We retrospectively and randomly reviewed 350 DXA examinations (142 lumbar spine, 129 femur, 10 forearm, 47 whole-body, 22 lateral vertebral assessment—Lunar iDXA, GE-Healthcare, USA) to find out incidental features in bone or soft tissues that may have or not any importance on patient clinical history, apart from the proper aim of DXA scans. Whenever an extra finding was discovered the physician report was read and a deeper search for other imaging methods was performed to understand whether that finding was already known or not. Additionally, scoliosis and arthrosis were detected and graded and other pitfalls were collected. Results: The population was made up of 54 males and 296 females (age 61±13 years old, BMI 27±6 Kg/m2). Incidental findings were detected in 56/350 (16.0%) DXA examinations: biliary stones (3.6%), urinary stones (3.6%), vascular calcifications (16.1%), other soft tissue calcifications (28.4%, e.g., calcified enthesopathies, calcified lymph nodes, uterin fibroma, suprarenal adenoma, portal cavernoma), vertebral abnormalities (33.9%, fractures, listhesis, additional vertebrae), old bone fractures or other bone abnormalities (5.4%), cardiomegaly (9.0%). Among all these findings 39.3% could get a confirmation by “more diagnostic” imaging modalities as gold standard; 90.9% of findings could be correctly identified (true positives) with oriented diagnoses by DXA but none of the them was mentioned on DXA reports. Foreign bodies and pitfalls were found in 6.8% of all DXA exams; 17.4% of all patients had moderate-severe arthrosis, and 14.6% scoliosis. Conclusions: An interpreting physician should treat the DXA image with the same attention given to any other Xray image, in reference to both incidental findings and pitfalls. Nevertheless some false findings may affect specificity and generate further unnecessary diagnostic examinations, with potential negative effects on patient care and economy.