Department of Radiology, German Armed Forces Hospital Ulm, Oberer Eselsberg 40, 89081, Ulm, Germany.
Department of Diagnostic and Interventional Radiology, University Hospital Würzburg, Oberdürrbacher Straße 6, 97080, Würzburg, Germany.
BMC Musculoskelet Disord. 2022 Jul 29;23(1):724. doi: 10.1186/s12891-022-05690-2.
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.
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.
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.
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.
人口结构变化导致脆性骨折的发病率不断上升。双能 CT（DECT）结合虚拟非钙（VNCa）重建技术已被引入，作为一种有前途的诊断方法，可同时评估骨微结构和骨髓。本研究旨在确定最佳的 CT 值截断值，以区分骶骨脆性骨折中骨髓水肿（BME）的存在和不存在。
46 例（40 名女性，6 名男性；79.7±9.2 岁）疑似骶骨脆性骨折的患者接受了 DECT（90 kVp/150 kVp 加锡预过滤）和 MRI 检查。在 DECT-VNCa 图像上对每个骶骨进行了 9 个感兴趣区（ROI）的定位。根据 T2 加权 MRI 序列中 BME 的参考检测，将 414 个 HU 测量值分为“水肿”（n=80）和“无水肿”（n=334）组。计算受试者工作特征曲线下的面积，以确定所需的截断值和水肿检测的显著范围。
测量值中“水肿”组的平均密度（+3.1±8.3 HU）明显高于“无水肿”组（-51.7±21.8 HU；p<0.010）。DECT-VNCa 图像分析提示，与 MRI 相比，-12.9 HU 的截断值可使 BME 检测的敏感性和特异性达到 100%。HU 值在-14.0 到+20.0 之间被认为提示骶骨存在 BME。
使用-12.9 HU 的 DECT-VNCa 定量分析可在评估伴有 BME 的骶骨脆性骨折时提供出色的诊断准确性。无需额外 MRI 的诊断“一站式”方法是可行的。
