American Journal of Neuroradiology, Vol 13, Issue 5 1429-1434, Copyright © 1992 by American Society of Neuroradiology
ARTICLES |
Fat suppression in combination with multiple overlapping thin-slab 3-D acquisition MR angiography: proposed technique for improved vessel visualization
RO Robison, DD Blatter, DL Parker, P Hou, JS Collins and WW Barney
Department of Radiology, LDS Hospital, Salt Lake City, Utah 84143.
PURPOSE: To study the parameters of the 1331 fat saturation pulse (saturation pulse flip angle (SPFA) and interpulse delay (tau)) in order to identify values that provide optimal vessel visibility. METHODS: Carotid bifurcations of three healthy subjects were studied. RESULTS: The optimal values for the SPFA and tau were 60 degrees (7.5 degrees, -22.5 degrees, 22.5 degrees, -7.5 degrees) and 2.0-3.0 msec, respectively. At these values there was a 1.56-fold increase (SD = +/- .12, P less than .01) in the contrast-to-noise ratio between the left internal carotid artery and fat compared to the study without fat saturation. A 3.0-fold increase was noted for the smaller left occipital artery. Additionally, there was no statistically significant reduction in the vessel-muscle contrast-to-noise ratio nor in the absolute vessel signal-to-noise ratio at these values. CONCLUSION: Implementation of fat saturation into carotid MR angiography markedly improves visualization of vascular anatomy without increasing imaging time.