Journal Article

Vessel architecture imaging using multiband gradient-echo/spin-echo EPI

Zhang, Ke, Bendszus, Martin, Yun, Seong Dae, Schlemmer, Heinz-Peter, Sturm, Volker J., Hahn, Artur, Shah, N. Jon, Ziener, Christian H., Kurz, Felix T., Triphan, Simon M. F., Buschle, Lukas R., Heiland, Sabine

2019

Overview

To apply the MB (multiband) excitation and blipped-CAIPI (blipped-controlled aliasing in parallel imaging) techniques in a spin and gradient-echo (SAGE) EPI sequence to improve the slice coverage for vessel architecture imaging (VAI). Both MB excitation and blipped-CAIPI with in-plane parallel imaging were incorporated into a gradient-echo (GE)/spin-echo (SE) EPI sequence for simultaneous tracking of the dynamic MR signal changes in both GE and SE contrasts after the injection of contrast agent. MB and singleband (SB) excitation were compared using a 20-channel head coil at 3 Tesla, and high-resolution MB VAI could be performed in 32 glioma patients. Whole-brain covered high resolution VAI can be achieved after applying multiband excitation with a factor of 2 and in-plane parallel imaging with a factor of 3. The quality of the images resulting from MB acceleration was comparable to those from the SB method: images were reconstructed without any loss of spatial resolution or severe distortions. In addition, MB and SB signal-to-noise ratios (SNR) were similar. A relative low g-factor induced from the MB acceleration method was achieved after using a blipped-CAIPI technique (1.35 for GE and 1.33 for SE imaging). Performing quantitative VAI, we found that, among all VAI parametric maps, microvessel type indicator (MTI), distance map (I) and vascular-induced bolus peak-time shift (VIPS) were highly correlated. Likewise, VAI parametric maps of slope, slope length and short axis were highly correlated. Multiband accelerated SAGE successfully doubles the number of readout slices in the same measurement time when compared to conventional readout sequences. The corresponding VAI parametric maps provide insights into the complexity and heterogeneity of vascular changes in glioma.

• Publisher: Public Library of Science,Public Library of Science (PLoS)
• Subject: Acceleration / Adult / Aged / Aged, 80 and over / Aircraft / Aliasing / Architecture / Biology and Life Sciences / Blood vessels / Blood Vessels - diagnostic imaging / Brain / Brain - blood supply / Brain - diagnostic imaging / Brain cancer / Brain Neoplasms - diagnostic imaging / Brain research / Brain tumors / Contrast agents / Contrast media / Contrast Media - chemistry / Echo-Planar Imaging / Edema / Excitation / Female / Gadoterate meglumine / Glioma / Gliomas / Heterogeneity / High resolution / Humans / Image quality / Image reconstruction / Imaging, Three-Dimensional / Magnetic resonance imaging / Male / Medical imaging / Medical research / Medicine and Health Sciences / Middle Aged / Neuroimaging / Neurosciences / Permeability / Physics / Research and Analysis Methods / Signal to noise ratio / Slopes / Spatial discrimination / Spatial resolution / Spin Labels / Tumors / Vortices