- Oral presentation
- Open Access
3D flow-insensitive vessel wall imaging using T2-prepared SSFP with PSIR
© Xie et al; licensee BioMed Central Ltd. 2010
Published: 21 January 2010
Double Inversion Recovery (DIR)  and Flow Sensitive Diffusion (FSD) have been used to in vessel wall imaging. However, the "black blood" effect of DIR and FSD depends on the inflow, which is sensitive to slow or in-plane flow. In this work, T1, T2 difference between blood/vessel wall was exploited using a T2-prepared non-selective inversion preparation for flow-insensitive vessel wall imaging. To alleviate the dependence of blood/vessel wall contrast on the choice of TI and heart rate in ECG-triggered data acquisition, a Phase Sensitive Inversion Recovery (PSIR)  approach was used.
A T2-preparation module was added before the inversion recovery of PSIR to improve contrast. In the T2PSIR module, a 90°x tip-down-pulse was used instead of the -90°x tip-up-pulse to include the inversion effect into the T2-prep. After a nominal TI of the T2IR module, a 3D SSFP acquisition with high flip angle (80°) was used to acquire data. With the same TI, another SSFP acquisition of low flip angle (8°) was played after the 2nd ECG trigger pulse, same in DE PSIR (Fig. 1). Because the T2 preparation and inversion pulses are all non-selective, this technique provides a flow-insensitive feature.
The peripheral arteries were imaged in seven healthy subjects on 3.0 T (Trio, Siemens). An ECG-triggered, 3D SSFP segmented T2PSIR sequence was used for acquisition. Parameters used were: TE 1.8 ms, TR 3.6 ms, TI 350 msec, T2preparation time 40 ms. resolution 0.7 × 0.7 × 2.0 mm, 32 slices, 30 k-space lines per segments, bandwidth 610 Hz/pixel with GRAPPA acceleration factor of 2.
Discussion and Conclusion
We have demonstrated a new technique that can achieve 3D flow-insensitive vessel wall imaging. This technique can acquire 64-mm-coverage in 4 minutes and has substantially improved imaging efficiency than single slice DIR method. More importantly, this technique is flow and TI-insensitive because of PSIR preparation. Further optimization of the technique is required to optimize CNR.
This article is published under license to BioMed Central Ltd.