Department of Radiology, New York University Langone Medical Center, 550 First Ave, New York, NY 10016, USA.
AJR Am J Roentgenol. 2012 Aug;199(2):387-93. doi: 10.2214/AJR.11.8043.
Total renal volume and changes in kidney volume are markers of disease progression in autosomal-dominant polycystic kidney disease (ADPKD) but are not used in clinical practice in part because of the complexity of manual measurements. This study aims to assess the intra- and interobserver reproducibility of a semiautomated renal volumetric algorithm using fluid-sensitive MRI pulse sequences.
Renal volumes of 17 patients with ADPKD were segmented from high-resolution coronal HASTE and true fast imaging with steady-state precession (FISP) MR acquisitions. Measurements performed independently by four readers were repeated, typically after 7 days. Intraobserver agreement indexes were calculated for total kidney volume for each patient. Interobserver agreement indexes were obtained for the six paired combinations of readers as well as for two readers after rigorous formalized training. Pearson and concordance correlation coefficients, coefficients of variation (CVs), and 95% limits of agreement were determined.
The HASTE and true FISP sequences performed similarly with a median intraobserver agreement of greater than 98.1% and a CV of less than 2.4% across all readers. The median interobserver agreement was greater than 95.2% and the CV was less than 7.1%, across all reader pairs. Reader training further lowered interobserver CV. The mean total kidney volume was 1420 mL (range, 331-3782 mL) for HASTE imaging and 1445 mL (range, 301-3714 mL) for true FISP imaging, with mean image processing times per patient of 43 and 28 minutes, respectively.
This semiautomated MR volumetric algorithm provided excellent intraobserver and very good interobserver reproducibility using fluid-sensitive pulse sequences that emphasize cyst conspicuity.
总肾体积和肾脏体积变化是常染色体显性多囊肾病（ADPKD）疾病进展的标志物，但并未在临床实践中使用，部分原因是手动测量较为复杂。本研究旨在评估使用液体敏感 MRI 脉冲序列的半自动肾脏容积算法的观察者内和观察者间可重复性。
从高分辨率冠状 HASTE 和真实快速成像稳态进动（FISP）MR 采集对 17 名 ADPKD 患者的肾脏体积进行分割。由四名独立读者进行的测量重复进行，通常在 7 天后进行。为每个患者计算了总肾体积的观察者内一致性指数。还获得了六个读者配对组合以及经过严格规范化培训的两个读者的观察者间一致性指数。确定了 Pearson 和一致性相关系数、变异系数（CV）和 95%一致性界限。
HASTE 和真实 FISP 序列的表现相似，所有读者的中位数观察者内一致性均大于 98.1%，CV 小于 2.4%。所有读者对中位数观察者间一致性大于 95.2%，CV 小于 7.1%。读者培训进一步降低了观察者间 CV。HASTE 成像的平均总肾体积为 1420ml（范围 331-3782ml），真实 FISP 成像的平均总肾体积为 1445ml（范围 301-3714ml），每位患者的平均图像处理时间分别为 43 分钟和 28 分钟。
该半自动 MR 容积算法使用强调囊肿显影的液体敏感脉冲序列提供了出色的观察者内和非常好的观察者间可重复性。
