Apparent diffusion coefficient (ADC) measurement in ovarian tumor: Effect of region‐of‐interest methods on ADC values and diagnostic ability

Abstract

The ROI shape influences ADC values and the optimal cutoff ADC values for differentiating benign from malignant ovarian tumors.

Diffusion‐weighted quantitative MRI of pleural abnormalities: Intra‐ and interobserver variability in the apparent diffusion coefficient measurements

“…Similar results were reported by Ohno et al, who found better performance of ADC compared to maximum standardized uptake value obtained from PET‐CT as a quantitative predictor of tumor treatment response after chemoradiotherapy in nonsmall‐cell lung cancer . However, the aim of our study was to assess the repeatability of different protocols of ADC measurement that are generally used in other organs and compartments . Thus, the best method of ADC measurement for clinical application in DW‐MRI of the pleura and its benefit in evaluating and predicting treatment response are yet to be determined by means of further studies.…”

“…Prior studies assessed the interobserver agreement of ADC quantification by using different methods in various tumors . However, none of the studies on DW‐MRI of pleural disease evaluated the measurement variability of the ADC between different readings or readers .…”

“…Several studies have shown the ability of quantitative DW‐MRI to characterize benign and malignant disease in different organs and compartments . However, several factors, which include also the manual method of region‐of‐interest (ROI) positioning for measuring the ADC, affect the measurement and can lead to unreliable values . Indeed, some investigators have found significant differences in ADC values by using different ROI methods in the same tumor, suggesting that the method of measurement significantly affects the ADC …”

“…[6][7][8][9][10][11] However, several factors, which include also the manual method of region-of-interest (ROI) positioning for measuring the ADC, affect the measurement and can lead to unreliable values. 2,3,[12][13][14][15][16][17][18][19] Indeed, some investigators have found significant differences in ADC values by using different ROI methods in the same tumor, suggesting that the method of measurement significantly affects the ADC. 20,21 Few recent studies have explored the usefulness of ADC measurements in the assessment of pleura with DW-MRI.…”

Diffusion Weighted Imaging for Differentiating Benign from Malignant Orbital Tumors: Diagnostic Performance of the Apparent Diffusion Coefficient Based on Region of Interest Selection Method

“…Whole-tumor ROI can overcome this problem, however, it is a time consuming process, which limits its clinical application (12). The influence of ROI selection methods on the ADC measurements has been evaluated in the liver (13), ovaries (14), pancreas (1115), and breast (16). However, to our knowledge, no previous study has addressed the influence of the three different ROI selection methods on the ADC measurements, and their diagnostic abilities for differentiating benign from malignant orbital tumors.…”