Myocardial first pass perfusion: Steady‐state free precession versus spoiled gradient echo and segmented echo planar imaging

Abstract

The imaging sequences used in first pass (FP) perfusion to date have important limitations in contrast-to-noise ratio (CNR), temporal and spatial resolution, and myocardial coverage. As a result, controversy exists about optimal imaging strategies for FP myocardial perfusion. Since imaging performance varies from subject to subject, it is difficult to form conclusions without direct comparison of different sequences in the same subject. The purpose of this study was to directly compare the saturation recovery SSFP technique to other more commonly used myocardial first pass perfusion techniques, namely spoiled GRE and segmented EPI. Differences in signal-to-noise ratio (SNR), CNR, relative maximal upslope (RMU) of signal amplitude, and artifacts at comparable temporal and spatial resolution among the three sequences were investigated in computer simulation, contrast agent doped phantoms, and 16 volunteers. The results demonstrate that SSFP perfusion images exhibit an improvement of approximately 77% in SNR and 23% in CNR over spoiled GRE and 85% SNR and 50% CNR over segmented EPI. Mean RMU was similar between SSFP and spoiled GRE, but there was a 58% increase in RMU with SSFP versus segmented EPI. Magn Reson Med 54:1123-1129, 2005.

Effects of respiratory cycle and body position on quantitative pulmonary perfusion by MRI

“…The SSFP sequence has a superior signal to noise ratio when compared with gradient echo sequences (21). Hence, we were able to use a small amount of contrast (average 1-2 mL) at a concentration much below the threshold for contrast saturation effects to analyze lung perfusion quantitatively (21,22). Our absolute perfusion results in normal volunteers were comparable to published data using a 3D gradient echo sequence (15).…”

Diagnostic accuracy of stress myocardial perfusion MRI and late gadolinium-enhanced MRI for detecting flow-limiting coronary artery disease: a multicenter study

“…In the current study, perfusion MRI yields sensitivities and specificities of 89% and 79% (AUC 0.92) by an observer with CMR training level of 3, and 83% and 71% (AUC 0.84) by an observer with CMR training level of 2 for the detection of patients with obstructive CAD. We employed saturation-recovery SSFP sequence for MR perfusion imaging in this study since this technique has been shown to have better signal-to-noise and contrast-to-noise ratio compared with spoiled gradient-echo and segmented echo-planar techniques [25]. Although SSFP perfusion is considered more susceptible to dark-rim artifacts, use of SSFP sequence resulted in at least no appreciable deterioration in diagnostic performance in our study cohort in comparison with previous reports.…”

Direct comparison of myocardial perfusion cardiovascular magnetic resonance sequences with parallel acquisition

“…Previous work has shown that car- diac motion during image acquisition (31) and spatial resolution (32) may have a significant effect on the appearance of artifacts. Previous authors suggest that the prevalence of banding artifacts with SSFP is related to its greater inherent CNR in comparison to the other sequences (33). In this study SSFP had the greatest CNR, but also the most artifacts.…”

“…Comparison of hEPI and GRE, showed comparable artifact and ischemia scores for hEPI (29). However, many studies have not necessarily had a suitable clinical dimension being limited by using doped phantoms, not comparing sequences in the same patients, performing only rest perfusion studies, or not systematically assessing the presence and severity of artifacts (33,34). In our study, hEPI scoring the least artifacts and the highest diagnostic confidence is consistent with the findings of Muhling et al (35), who demonstrated that interobserver agreement as well as sensitivity to perfusion defects is related to both image quality and SNR.…”