6904 Conventional 2 D - EPI or Segmented 3 D - EPI ? A Temporal SNR Study at 3 and 7 Tesla
نویسندگان
چکیده
Purpose: Recently, segmented 3D-EPI has been proposed for application of BOLD functional MRI at ultra-high fields such as 7 Tesla. Unfortunately, the statistical power, especially of 3D-EPI time series data, is limited by physiological noise (signal fluctuations due to breathing, etc.): with increasing base SNR the temporal SNR (tSNR=AVG/STD with respect to time) tends towards a constant value, which is smaller the more shots per EPI-volume are required. This work compares the tSNR and signal sensitivity (tSNR/√acquisi on me) characteristics of 2D-EPI vs. 3D-EPI under “real-life” conditions, i.e. for different lowand high resolution protocols for fast fMRI data acquisition at 7 and 3 Tesla.
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