Breath-hold signal-loss sequence for the qualitative assessment of flow disturbances in cardiovascular MR
✍ Scribed by Jennifer Keegan; Peter D. Gatehouse; Anna S. John; Raad H. Mohiaddin; David N. Firmin
- Book ID
- 102905273
- Publisher
- John Wiley and Sons
- Year
- 2003
- Tongue
- English
- Weight
- 534 KB
- Volume
- 18
- Category
- Article
- ISSN
- 1053-1807
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✦ Synopsis
Abstract
Purpose
To develop a breath‐hold segmented sequence which generates similar patterns of signal loss to a non–breath‐hold, relatively long echo time, conventional gradient echo sequence for the qualitative assessment of valvular heart disease.
Materials and Methods
Both velocity‐sensitized and acceleration‐sensitized segmented sequences were developed. The sensitivities were empirically adjusted to give similar degrees of signal loss to a conventional sequence. These sequences were compared with a conventional sequence in eight patients with flow disturbances and in four healthy subjects.
Results
There was no significant difference in the extent of signal loss observed when using the breath‐hold velocity‐ and acceleration‐sensitized sequences developed and the conventional sequence (1862 mm^2^, 1831 mm^2^, and 1782 mm^2^, respectively; P = ns). However, the image quality obtained was significantly better with the breath‐hold sequences (both P < 0.01). Furthermore, the image quality achieved with the acceleration‐sensitized sequence was significantly better than that achieved with the velocity‐sensitized sequence (P < 0.01) where artifacts from beat‐to‐beat variations in blood‐flow velocities were a frequent problem.
Conclusion
Signal loss in complex flow is best demonstrated using the breath‐hold acceleration‐sensitized sequence where the signal from both stationary and constant velocity material is rephased at the echo time.