TY - JOUR
T1 - Variability of consecutive in vivo MR flow measurements in the main portal vein
AU - Hara, Amy K.
AU - Burkart, David J.
AU - Johnson, C. Daniel
AU - Felmlee, Joel P.
AU - Ehman, Richard L.
AU - Ilstrup, Duane M.
AU - Harmsen, W. Scott
N1 - Copyright:
Copyright 2017 Elsevier B.V., All rights reserved.
PY - 1996/6
Y1 - 1996/6
N2 - OBJECTIVE. The variability of consecutive cine phase-contrast MR flow measurements could significantly affect their use for clinical decisions, especially during provocative testing. The purposes of this study were to determine the normal variability of flow and consecutive flow measurements in the main portal vein on MR images and to determine how intraobserver variability, interobserver variability, and MR imager variability affect these measurements. SUBJECTS AND METHODS. MR flow measurements were acquired four consecutive times at the same location in the main portal vein of 12 subjects and three consecutive times at the same location in a nonpulsatile vessel model. All acquisitions were completed within 10 min. All main portal vein MR data sets were evaluated manually in a blinded review by two independent observers during three separate sessions spaced a mean of 4.5 weeks apart. Flow model data sets were evaluated during a single session by one observer. Variabilities were subsequently calculated by a components-of- variance analysis and by the coefficient of variation (SD/mean x 100). RESULTS. Of the total variance, 90% was due to flow variability among subjects (intersubject), 6% to flow variability within one subject (intrasubject), 2% to intraobserver variability, and 2% to interobserver variability. The coefficient of variation of consecutive MR portal vein flow measurements within a single subject was 11% ± 5% (range, 3-23%). Intra- and interobserver variabilities were 5% ± 2% (range, 1-11%) and 4% ± 4% (range, 017%), respectively. MR imager variability was 1% ± 1% (range, 0-2%). CONCLUSION. The mean variability of consecutive cine phase-contrast MR flow measurements in the main portal vein is 11% ± 5% and could affect research and clinical protocols that employ this technique.
AB - OBJECTIVE. The variability of consecutive cine phase-contrast MR flow measurements could significantly affect their use for clinical decisions, especially during provocative testing. The purposes of this study were to determine the normal variability of flow and consecutive flow measurements in the main portal vein on MR images and to determine how intraobserver variability, interobserver variability, and MR imager variability affect these measurements. SUBJECTS AND METHODS. MR flow measurements were acquired four consecutive times at the same location in the main portal vein of 12 subjects and three consecutive times at the same location in a nonpulsatile vessel model. All acquisitions were completed within 10 min. All main portal vein MR data sets were evaluated manually in a blinded review by two independent observers during three separate sessions spaced a mean of 4.5 weeks apart. Flow model data sets were evaluated during a single session by one observer. Variabilities were subsequently calculated by a components-of- variance analysis and by the coefficient of variation (SD/mean x 100). RESULTS. Of the total variance, 90% was due to flow variability among subjects (intersubject), 6% to flow variability within one subject (intrasubject), 2% to intraobserver variability, and 2% to interobserver variability. The coefficient of variation of consecutive MR portal vein flow measurements within a single subject was 11% ± 5% (range, 3-23%). Intra- and interobserver variabilities were 5% ± 2% (range, 1-11%) and 4% ± 4% (range, 017%), respectively. MR imager variability was 1% ± 1% (range, 0-2%). CONCLUSION. The mean variability of consecutive cine phase-contrast MR flow measurements in the main portal vein is 11% ± 5% and could affect research and clinical protocols that employ this technique.
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U2 - 10.2214/ajr.166.6.8633438
DO - 10.2214/ajr.166.6.8633438
M3 - Article
C2 - 8633438
AN - SCOPUS:0029975671
SN - 0361-803X
VL - 166
SP - 1311
EP - 1315
JO - American Journal of Roentgenology
JF - American Journal of Roentgenology
IS - 6
ER -