Dual-energy CT in sacral fragility fractures: defining a cut-off Hounsfield unit value for the presence of traumatic bone marrow edema in patients with osteoporosis

Abstract

Background Demographic change entails an increasing incidence of fragility fractures. Dual-energy CT (DECT) with virtual non-calcium (VNCa) reconstructions has been introduced as a promising diagnostic method for evaluating bone microarchitecture and marrow simultaneously. This study aims to define the most accurate cut-off value in Hounsfield units (HU) for discriminating the presence and absence of bone marrow edema (BME) in sacral fragility fractures. Methods Forty-six patients (40 women, 6 men; 79.7 ± 9.2 years) with suspected fragility fractures of the sacrum underwent both DECT (90 kVp / 150 kVp with tin prefiltration) and MRI. Nine regions-of-interest were placed in each sacrum on DECT-VNCa images. The resulting 414 HU measurements were stratified into “edema” (n = 80) and “no edema” groups (n = 334) based on reference BME detection in T2-weighted MRI sequences. Area under the receiver operating characteristic curve was calculated to determine the desired cut-off value and an associated conspicuity range for edema detection. Results The mean density within the “edema” group of measurements (+ 3.1 ± 8.3 HU) was substantially higher compared to the “no edema” group (-51.7 ± 21.8 HU; p < 0.010). Analysis in DECT-VNCa images suggested a cut-off value of -12.9 HU that enabled sensitivity and specificity of 100% for BME detection compared to MRI. A range of HU values between -14.0 and + 20.0 is considered indicative of BME in the sacrum. Conclusions Quantitative analysis of DECT-VNCa with a cut-off of -12.9 HU allows for excellent diagnostic accuracy in the assessment of sacral fragility fractures with associated BME. A diagnostic “one-stop-shop” approach without additional MRI is feasible.

Assessment of bone marrow edema on dual-energy CT scans in people with diabetes mellitus and suspected Charcot neuro-osteoarthropathy

“…Since there is a need for an early and accurate diagnosis, virtual non-calcium (VNCa) images calculated from dual-energy Computed Tomography (DECT) could be of value for rapid detection of bone marrow edema in the midfoot related to CN. DECT has shown to have a high sensitivity and specificity for detecting BME in multiple pathologies, including occult fractures, osteomyelitis and forms of arthritis [16][17][18][19][20][21].…”

Obesity-Related Pitfalls of Virtual versus True Non-Contrast Imaging—An Intraindividual Comparison in 253 Oncologic Patients

“…Dual-energy computed tomography (DECT) has been established in an increasing number of applications for multiple body regions in recent years [1][2][3][4][5][6][7]. However, DECT can result in longer reading times for radiologists due to increased information content [8].…”