Magnetic resonance imaging of the upper abdomen using a free-breathing T2-weighted turbo spin echo sequence with navigator triggered prospective acquisition correction

• Published in: Journal of magnetic resonance imaging Vol. 21; no. 5; pp. 576 - 582
• Main Authors: Klessen, Christian, Asbach, Patrick, Kroencke, Thomas J., Fischer, Thomas, Warmuth, Carsten, Stemmer, Alto, Hamm, Bernd, Taupitz, Matthias
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 01-05-2005
• Subjects: abdomen; Abdomen - pathology; Adult; Digestive System Diseases - diagnosis; Female; Humans; Image Processing, Computer-Assisted; Liver Diseases; Magnetic Resonance Imaging - methods; Male; Middle Aged; MRI; navigator echo; Respiration; respiratory trigger; Statistics, Nonparametric; T2-weighted imaging
• ISSN: 1053-1807; 1522-2586
• DOI: 10.1002/jmri.20293

Purpose
To evaluate a free‐breathing navigator triggered T2‐weighted turbo spin‐echo sequence with prospective acquisition correction (T2w‐PACE‐TSE) for MRI of the upper abdomen in comparison to a conventional T2‐weighted TSE (T2w‐CTSE), a single‐shot TSE (T2w‐HASTE), and a T1‐weighted gradient‐echo sequence (T1w‐FLASH).
Materials and Methods
A total of 40 consecutive patients were examined at 1.5 T using free‐breathing T2w‐PACE‐TSE, free‐breathing T2w‐CTSE, and breath‐hold T2w‐HASTE and T1w‐FLASH acquisition. Images were evaluated qualitatively by three radiologists regarding motion artifacts, liver‐spleen contrast, depiction of intrahepatic vessels, the pancreas and the adrenal glands, and overall image quality on a four‐point scale. Quantitative analysis of the liver‐spleen contrast was performed.
Results
Depiction and sharpness of intrahepatic vessels were rated significantly better (P < 0.01) using T2w‐PACE‐TSE compared to T2w‐CTSE and T2w‐HASTE sequences. Significantly higher contrast values were measured for T2w‐PACE‐TSE images compared to T2w‐CTSE, T2w‐HASTE, and T1w‐FLASH images (P < 0.01). Mean examination time of the T2w‐PACE‐TSE was 7.91 minutes, acquisition time of the T2w‐CTSE sequence was 4.52 minutes.
Conclusion
Prospective acquisition correction is an efficient method for reducing respiratory movement artifacts in T2w‐TSE imaging of the upper abdomen. Compared to T2w‐CTSE and T2w‐HASTE sequences recognition of anatomical details and contrast can be significantly improved. J. Magn. Reson. Imaging 2005;21:576–582. © 2005 Wiley‐Liss, Inc.