Tsang-Wei Tu1,2, Matthew D. Budde3, James D. Quirk2, Sheng-Kwei Song2
1Mechanical, Aerospace and Structural Engineering, Washington University in St. Louis, Saint Louis, MO, United States; 2Radiology, Washington University in St. Louis, Saint Louis, MO, United States; 3Radiology and Imaging Science, National Institutes of Health Clinical Center, Bethesda, MD, United States
Diffusion-weighted multiple spin echo (DW-MSE) sequences have been introduced to improve DTI quality without increasing scan time by combining the images of multiple echoes. Since complex image combination can cause artifacts due to phase variations between echoes, magnitude images are often employed. But this results in a noise distribution change from Gaussian to Rician leading to a SNR decline and biased tensor estimation. Our results demonstrate that absorption-mode addition of multiple echoes obtained using the DW-MSE sequence improves SNR by nearly 50% compared to a conventional DW-SE sequence and also overcomes the problem of phase variations without Rician noise complications.