Towards clinical application of 7T TOF angiography
نویسندگان
چکیده
Background As shown at 7T Time-of-Flight (TOF) angiography significantly benefits from ultra high field (UHF) [1,2], because of shorter T1 relaxation constant and increased SNR. However, significant challenges have to be overcome before using 7T TOF in clinical applications: I) RF induced specific absorption rate (SAR) substantially increases at UHF, preventing the use of standard RF pulses (venous Saturation (SAT), Magnetization Transfer (MT)) to improve TOF contrast. II) Severe transmit B1 (B1+) heterogeneity at 7T impairs contrast homogeneity.
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