Serge DumoulinNull-findings are important, but more difficult to prove and publish. Here is a null-finding #NewPaper / #NeuroNewPaper.
Line-scanning functional #MRI has both high spatial and high temporal resolutions, about 200 micrometers and 200 milliseconds. This is achieved by sacrificing spatial coverage, akin to a virtual BOLD electrode through the brain. Previously, we implemented a human line-scanning sequence using gradient-echo #BOLD #fMRI at 7T.
Spin-echo MRI sequences offer several advantages over gradient-echo MRI sequences, for example much improved spatial line-selection and microvascular specificity. However, despite many efforts, especially from the lead-author Luisa Raimondo, spin-echo line-scanning currently lacks adequate sensitivity for #neuroscience applications.
https://link.springer.com/article/10.1007/s10334-022-01059-7
Towards functional spin-echo BOLD line-scanning in humans at 7T - Magnetic Resonance Materials in Physics, Biology and Medicine
Objective Neurons cluster into sub-millimeter spatial structures and neural activity occurs at millisecond resolutions; hence, ultimately, high spatial and high temporal resolutions are required for functional MRI. In this work, we implemented a spin-echo line-scanning (SELINE) sequence to use in high spatial and temporal resolution fMRI. Materials and methods A line is formed by simply rotating the spin-echo refocusing gradient to a plane perpendicular to the excited slice and by removing the phase-encoding gradient. This technique promises a combination of high spatial and temporal resolution (250 μm, 500 ms) and microvascular specificity of functional responses. We compared SELINE data to a corresponding gradient-echo version (GELINE). Results We demonstrate that SELINE showed much-improved line selection (i.e. a sharper line profile) compared to GELINE, albeit at the cost of a significant drop in functional sensitivity. Discussion This low functional sensitivity needs to be addressed before SELINE can be applied for neuroscientific purposes.