Aims and objectives
Motion-induced artifacts are a well-known challenge for dynamic contrast- enhanced abdominal MR imaging.
Especially elderly patients and severely ill patients are often unable to adequately perform breath-hold maneuvers with a risk of critically reduced image quality due to motion artifacts and consequently impaired interpretability of the imaging material.
Recently fast multiphase contrast-enhanced sequences with artifact reduction by motion-insensitive radial acquisitions were introduced (1-3).
Long reconstruction times and necessity of an external reconstruction server limited clinical applicability of these approaches for older MR systems.
The purpose...
Methods and materials
So far,
20 datasets (10 fbVIBE/10 bhVIBE) were independently assessed by two experienced readers in this IRB-approved study.
All fbVIBE/bhVIBE sequences (temporal resolution: approximately 11/18 seconds) were performed on state-of-the-art 1.5T clinical MRI scanners (MAGNETOM Avanto Fit/Aera,
Siemens Healthcare,
Erlangen,
Germany).
Initial cs reconstruction using hard-gating to reduce respiratory motion artifacts was carried out on the scanner during the examination (duration: approximately 8 minutes).
Mann-Whitney U-tests were performed to compare image quality (IQ),
delineation of structures (DoS),
artifacts (A) and diagnostic confidence (DC),
which were...
Results
Ratings for IQ/DoS/DC of fbVIBE (3.8±0.6/3.7±0.8/4±0.8; κ:>0.5) and bhVIBE (3.3±0.8/3.4±0.8/3.6±1; κ:>0.8) were moderate to high,
while A was rated moderate to low (fb/bhVIBE: 2.5±1/2.8±1.1; κ:>0.4).
Mann Whitney U-test showed no significant difference between IQ/DoS/DC of fb/bhVIBE (p=0.19/p=0.46/p=0.34),
despite a trend towards superiority of fbVIBE was observed.
Conclusion
Fast fbVIBE using cs-reconstruction is technically feasible at a similar image quality compared to bhVIBE.
Secondary cs-reconstruction will presumably further improve image quality.
fbVIBE may be useful,
particularly in elderly and/or severely ill patients with impaired breath-hold capabilities.
Personal information
PD Dr.
med.
Daniel Hausmann
Leitender Arzt
Leiter des Fachbereiches „Abdominale und Onkologische Diagnostik“
Kantonsspital Baden AG
Institut für Radiologie
CH-5404 Baden
Telefon Zentrale +41 (0)56 486 21 11
Telefon direkt +41 (0)56 486 38 22
Telefax +41 (0)56 486 38 09
E-Mail:
[email protected]
www.ksb.ch
References
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"One-Stop Shop": Free-Breathing Dynamic Contrast-Enhanced Magnetic Resonance Imaging of the Kidney Using Iterative Reconstruction and Continuous Golden-Angle Radial Sampling.
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Invest Radiol.
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Xu J,
Axel L,
Sodickson DK,
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Magn Reson Med.
2014 Sep;72(3):707-17.
3....