Long-T2- and Fat-Suppressed Cortical Bones Imaging by Using Quiet MRI PETRA Sequence

Motivation: Visualizing cortical bone with short T2 value is challenging since long-T2 tissues and fat usually obscure it. Goal(s): This study develops a new long-T2- and lipidic tissue-suppressed sequence with silent acoustic noise to improve patient scanning comfort. Approach: We use an AFP inversion RF with controlled timing to maintain the long-T2 components at a low level and optimize the sequence parameters to null the fat signal. Results: We apply the PETRA to reduce the SPL to only 1.9 dBA higher than the background. The head cortical bone structure can be successfully visualized with positive contrast. Impact: The designed silent long-T2 tissue-suppressed PETRA sequence can be potentially useful for investigating the newborns bone development, which can decrease neonatal hearing injury risks and might be helpful for early-age skeletal maturation assessment.