Apparent Diffusion Coefficient (ADC) Measurement in Endometrial Carcinoma: Effect of Region of Interest Methods on ADC Values

作者：Inoue Chie^*; Fujii Shinya; Kaneda Sachi; Fukunaga Takeru; Kaminou Toshio; Kigawa Junzo; Harada Tasuku; Ogawa Toshihide

来源：Journal of Magnetic Resonance Imaging, 2014, 40(1): 157-161.

DOI：10.1002/jmri.24372

• MR
• diffusion
• apparent diffusion coefficient
• ADC
• endometrial carcinoma
• ROI

Purpose: To investigate the influence of different-shaped regions of interest (ROIs) on tumor apparent diffusion coefficient (ADC) measurements and interobserver variability in endometrial carcinoma. %26lt;br%26gt;Materials and Methods: Sixty-nine patients (age range, 32-92 years; mean, 61 years) were evaluated in this retrospective study. Patients had undergone magnetic resonance (MR) examinations including diffusion-weighted imaging (DWI) using a 3.0-T MR system. Two readers measured tumor ADCs using four ROI methods: freehand ROI; square ROI; round ROI; and five small, round ROIs. Minimum and mean ADCs were obtained. The interclass correlation coefficient (ICC) was statistically analyzed to assess measurement reliability. Repeated-measures analysis of variance was used for comparisons of ADCs measured with each ROI method. %26lt;br%26gt;Results: ICCs were 0.93 (minimum ADC) / 0.93 (mean ADC) for freehand ROIs, 0.94/0.95 for square ROIs, 0.94/0.95 for round ROIs, and 0.95/0.96 for five small, round ROIs. All ROI methods indicated excellent correlations. Each minimum ADC was significantly different except between square ROI and round ROI (P %26lt; 0.001). Mean ADCs showed significant differences only between freehand ROI and the other ROI methods (P %26lt; 0.001). %26lt;br%26gt;Conclusion: ROI shape has no marked influence on ICC in endometrial carcinoma. Compared with minimum ADCs, mean ADCs are suggested to provide more stable results regardless of the ROI method.

• 出版日期2014-7