TY - JOUR
T1 - Interobserver variability of selective region-of-interest measurement protocols for quantitative diffusion weighted imaging in soft tissue masses
T2 - Comparison with whole tumor volume measurements
AU - Ahlawat, Shivani
AU - Khandheria, Paras
AU - Del Grande, Filippo
AU - Morelli, John
AU - Subhawong, Ty
AU - Demehri, Shadpour
AU - Fayad, Laura M.
PY - 2016/2/1
Y1 - 2016/2/1
N2 - Background To assess the interobserver reliability of three selective region-of-interest (ROI) measurement protocols for apparent diffusion coefficient (ADC) quantifications in soft tissue masses (STMs) compared with whole tumor volume (WTV) ADC measurements. Methods Institutional review board approval was obtained and informed consent was waived. Three observers independently measured minimum and mean ADCs of 73 benign and malignant musculoskeletal STMs using three selective methods (single-slice [SS], predefined three slices [PD], observer-based [OB]) and WTV measurements at 3.0 Tesla. Minimum and mean ADC values derived from each method were compared with WTV measurements, and inter-reader variation was assessed using the intraclass correlation coefficient (ICC). The time required for each method of ADC measurement was recorded. Results For the SS, PD, OB, and WTV methods, minimum ADC values ((×10-3 mm2/s)) were 0.97, 0.78, 0.73, and 0.67, respectively, and mean ADC values ((×10-3 mm2/s)) were 1.49, 1.49, 1.51, and 1.49, respectively. Interobserver agreement was good to excellent for the minimum and mean ADC values for the three readers using the SS, PD, OB, and WTV (ICC range 0.78-0.90). The SS, PD and OB methods required the least amount of measurement time (14 ± 5, 40 ± 17, and 38 ± 15 s, respectively) while the reference WTV method required the longest measurement time (111 ± 54 s) (P <0.01). Conclusion While all selective and WTV measurements offer good to excellent interobserver agreement, the selective OB method of ADC measurement results in the closest values to WTV measurements and requires significantly less measurement time than that required for the WTV method. J. Magn. Reson. Imaging 2016;43:446-454.
AB - Background To assess the interobserver reliability of three selective region-of-interest (ROI) measurement protocols for apparent diffusion coefficient (ADC) quantifications in soft tissue masses (STMs) compared with whole tumor volume (WTV) ADC measurements. Methods Institutional review board approval was obtained and informed consent was waived. Three observers independently measured minimum and mean ADCs of 73 benign and malignant musculoskeletal STMs using three selective methods (single-slice [SS], predefined three slices [PD], observer-based [OB]) and WTV measurements at 3.0 Tesla. Minimum and mean ADC values derived from each method were compared with WTV measurements, and inter-reader variation was assessed using the intraclass correlation coefficient (ICC). The time required for each method of ADC measurement was recorded. Results For the SS, PD, OB, and WTV methods, minimum ADC values ((×10-3 mm2/s)) were 0.97, 0.78, 0.73, and 0.67, respectively, and mean ADC values ((×10-3 mm2/s)) were 1.49, 1.49, 1.51, and 1.49, respectively. Interobserver agreement was good to excellent for the minimum and mean ADC values for the three readers using the SS, PD, OB, and WTV (ICC range 0.78-0.90). The SS, PD and OB methods required the least amount of measurement time (14 ± 5, 40 ± 17, and 38 ± 15 s, respectively) while the reference WTV method required the longest measurement time (111 ± 54 s) (P <0.01). Conclusion While all selective and WTV measurements offer good to excellent interobserver agreement, the selective OB method of ADC measurement results in the closest values to WTV measurements and requires significantly less measurement time than that required for the WTV method. J. Magn. Reson. Imaging 2016;43:446-454.
KW - ADC measurement
KW - DWI
KW - interobserver reliability
KW - soft tissue masses
UR - http://www.scopus.com/inward/record.url?scp=84961226293&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84961226293&partnerID=8YFLogxK
U2 - 10.1002/jmri.24994
DO - 10.1002/jmri.24994
M3 - Article
C2 - 26174705
AN - SCOPUS:84961226293
VL - 43
SP - 446
EP - 454
JO - Journal of Magnetic Resonance Imaging
JF - Journal of Magnetic Resonance Imaging
SN - 1053-1807
IS - 2
ER -