METHODS: We reviewed MRI images of 80 patients with anterior shoulder instability with Osirix software using MPR. Six observers with basic experience measured the glenoid, erosion edge length, and bone loss twice, with at least one-week interval between measurements. We calculated reliability and repeatability using the intra-class correlation coefficient (ICC) and minimal detectable change with 95% confidence (MDC95%).
RESULTS: Intra and Inter-observer ICC and MDC95% for glenoid width and height were excellent (ICC 0,89-0,96). For erosion edge length and area of the glenoid were acceptable/good (ICC 0,61-0,89). Bone loss and Pico Index were associated with acceptable/good ICC (0,63 -0,86)) but poor MDC95% (45 - 84 %). Intra-observer reliability improved with time, while inter-observer remained unchanged.
CONCLUSIONS: The MPR MRI measurement of the anterior glenoid lesion is very good tool for linear parameters. This method is not valid for Pico index measurement, as the area of bone loss is variable. The pace of learning is individual, therefore complex calculations based on MPR MRI are not resistant to low experience as opposed to true 3D CT.
方法:我们使用MPR使用Osirix软件回顾了80例肩关节前不稳定患者的MRI图像。六个有基本经验的观察者测量了关节盂,侵蚀边缘长度,和骨质流失两次,测量之间至少间隔一周。我们使用类内相关系数(ICC)和最小可检测变化以95%的置信度(MDC95%)计算可靠性和可重复性。
结果:对于关节盂宽度和高度,观察者内和观察者间的ICC和MDC95%都非常好(ICC0,89-0,96)。对于侵蚀边缘长度和关节盂面积是可接受/良好的(ICC0,61-0,89)。骨丢失和Pico指数与可接受/良好的ICC(0,63-0,86)相关,但MDC95%(45-84%)较差。观测器内可靠性随着时间的推移而提高,而观察者之间保持不变。
结论:前关节盂病变的MPRMRI测量是线性参数的非常好的工具。此方法对Pico指数测量无效,骨丢失的面积是可变的。学习的步伐是个人的,因此,与真正的3DCT相比,基于MPRMRI的复杂计算对低经验没有抵抗力。