In:
Circulation, Ovid Technologies (Wolters Kluwer Health), Vol. 108, No. 11 ( 2003-09-16), p. 1355-1361
Abstract:
Background— Parallel imaging by sensitivity encoding (SENSE) may considerably reduce scan time in MRI. For rapid flow quantification in children with congenital heart disease, we evaluated phase-contrast MRI (PC-MRI) techniques combined with SENSE. Methods and Results— In 22 pediatric patients (mean age, 7.2±6.2 years) with cardiac left-to-right shunt, blood flow rate in the pulmonary artery (Q p ) and ascending aorta (Q s ) and flow ratio Q p /Q s were determined by PC-MRI with SENSE reduction-factor 2 and 3 (SF-2 and SF-3). Additionally, we used PC-MRI with higher spatial in-plane resolution (1.6×2.1 versus 2.3×3.1 mm) with and without SF-3. Results were compared with a recently validated standard PC-MRI protocol and tested in vitro using a pulsatile flow phantom. Reduction of signal averages from 2 to 1 and application of SENSE accelerated flow measurements by a factor of 3.5 (5.2) using PC-MRI with SF-2 (SF-3) compared with standard PC-MRI. For blood flow rate through the pulmonary artery and aorta, as well as for the Q p /Q s ratio we found negligible differences of ±3%, lower limits of agreement (mean±2 SD) of −7% to −18%, and upper limits of agreement (mean±2 SD) of +3 to +24%, demonstrating good agreement with standard PC-MRI. Mean Q p /Q s ratio by standard PC-MRI was 1.69±0.45 (range, 1.27 to 2.79). Interobserver variability was low, and high accuracy was confirmed in vitro for all protocols. Conclusions— PC-MRI for flow quantitation may be combined with SENSE to achieve a substantive reduction of scanning time. In children with left-to-right shunt, Q p /Q s quantification is possible by PC-MRI+SF-3 in 〈 60 seconds. Use of higher in-plane resolution did not improve measurement results.
Type of Medium:
Online Resource
ISSN:
0009-7322
,
1524-4539
DOI:
10.1161/01.CIR.0000087603.97036.C2
Language:
English
Publisher:
Ovid Technologies (Wolters Kluwer Health)
Publication Date:
2003
detail.hit.zdb_id:
1466401-X
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