부산대학교 도서관

Magnetic resonance first-pass (MRFP) imaging awaits longitudinal clinical trials for quantification of myocardial perfusion. The purpose of this study was to assess inter- and intraobserver agreement of this method. Seventeen MRFP studies (14 rest and 3 under adenosine-induced hyperemia) from 14 patients were acquired. Two observers visually graded study quality. Each study was subdivided into eight regions. Both observers analyzed all 17 studies (8 x 17 = 136 regions) for interobserver agreement. Each observer then analyzed 10 of the 17 studies a second time (2 x 8 x 10 = 160 regions) for intraobserver agreement. Signal intensity curves were obtained with Argus software (Siemens, Iselin, NJ). The maximum amplitude of the impulse response function (R[sub max]) and the change of signal intensity (ΔSI[sub max]) of the contrast bolus were determined. Intraclass correlation coefficient was used to determine intra- and interobserver agreement. The quality was good or excellent in 14 studies. Intraobserver agreement of R[sub max] and ΔSI[sub max] were good (0.85 and 0.80, n = 160). Interobserver agreement of R[sub max] was fair (0.55, n = 136) but improved after exclusion of poor-quality studies (0.88, n = 112). Interobserver agreement of ΔSI[sub max] was good (0.73) and improved less than R[sub max] with study quality (0.83). Interobserver agreement for R[sub max] in individual myocardial regions before and after exclusion of studies with poor quality changed most markedly in lateral and posterior regions (0.69 and 0.65 vs. 0.97 and 0.94), where signal-to-noise ratios were reduced compared with anteroseptal regions (p < 0.01). Analysis of MRFP images provides good intraobserver agreement. Interobserver agreement of the quantitative perfusion analysis is good under the premise of good image quality. [ABSTRACT FROM AUTHOR]