Department of Diagnostic and Interventional Radiology, University Hospital Würzburg, Oberdürrbacher Straße 6, 97080 Würzburg, Germany.
Department of Diagnostic and Interventional Radiology, University Hospital Würzburg, Oberdürrbacher Straße 6, 97080 Würzburg, Germany.
Acad Radiol. 2021 Oct;28(10):e314-e322. doi: 10.1016/j.acra.2020.06.018. Epub 2020 Jul 10.
Cone-beam CT (CBCT) applications possess potential for dose reduction in musculoskeletal imaging. This study evaluates the ultra-high-resolution CBCT prototype of a twin robotic X-ray system in wrist examinations compared to high-resolution multidetector CT (MDCT).
Sixteen wrists of body donors were examined with the CBCT scan mode and a 384 slice MDCT system. Radiation-equivalent low-dose (CTDI = 3.3 mGy) and full-dose protocols (CTDI = 13.8 mGy) were used for both systems. Two observers assessed image quality on a seven-point Likert scale. In addition, software-assisted quantification of signal intensity fractions in cancellous bone was performed. Fewer pixels with intermediate signal intensity were considered to indicate superior depiction of bone microarchitecture.
Subjective image quality in CBCT was superior to dose equivalent MDCT with p ≤ 0.03 for full-dose and p < 0.001 for low-dose scans, respectively. Median Likert values were 7/7 (reader 1 / reader 2) in full-dose CBCT, 6/6 in full-dose MDCT, 5/6 in low-dose CBCT and 3/3 in low-dose MDCT. Intraclass correlation coefficient was 0.936 (95% confidence interval, 0.897-0.961; p < 0.001), indicating excellent reliability. Objective analysis displayed smaller fractions of "indecisive" pixels with intermediate signal intensity for full-dose CBCT (0.57 [interquartile range 0.13]) compared to full-dose MDCT (0.68 [0.21]), low-dose CBCT (0.72 [0.19]), and low-dose MDCT (0.80 [0.15]) studies. No significant difference was observed between low-dose CBCT and full-dose MDCT.
The new CBCT prototype provides superior image quality for trabecula and bone marrow in cadaveric wrist studies and enables dose reduction up to 75% compared to high-resolution MDCT.
锥形束 CT（CBCT）在肌肉骨骼成像中具有降低剂量的潜力。本研究评估了双机器人 X 射线系统的超高清 CBCT 原型在腕关节检查中的应用，与高分辨率多排 CT（MDCT）相比。
使用 CBCT 扫描模式和 384 层 MDCT 系统对 16 个尸体腕关节进行检查。两种系统均使用辐射等效低剂量（CTDI=3.3 mGy）和全剂量方案（CTDI=13.8 mGy）。两位观察者使用七点李克特量表评估图像质量。此外，还使用软件辅助评估松质骨中信号强度分数的定量分析。具有中等信号强度的像素越少，表明骨微观结构的显示越好。
全剂量 CBCT 的主观图像质量优于剂量等效 MDCT（全剂量扫描时 p≤0.03，低剂量扫描时 p<0.001）。全剂量 CBCT 的中位数李克特值为 7/7（观察者 1/观察者 2），全剂量 MDCT 为 6/6，低剂量 CBCT 为 5/6，低剂量 MDCT 为 3/3。组内相关系数为 0.936（95%置信区间，0.897-0.961；p<0.001），表明具有极好的可靠性。客观分析显示，全剂量 CBCT 中具有中等信号强度的“不确定”像素比例较小（0.57[四分位间距 0.13]），与全剂量 MDCT（0.68[0.21]）、低剂量 CBCT（0.72[0.19]）和低剂量 MDCT（0.80[0.15]）相比。低剂量 CBCT 与全剂量 MDCT 之间无显著差异。
新型 CBCT 原型在尸体腕关节研究中提供了优于高分辨率 MDCT 的小梁和骨髓的图像质量，并可将剂量降低高达 75%。
