Dual echo gradient echo imaging for simultaneous thermal mapping in cortical bone and soft tissue
نویسندگان
چکیده
Background/introduction MRI-guided high-intensity focused ultrasound (MRHIFU) therapy can relieve pain associated with metastatic and benign bone tumours in patients who fail to respond to conventional radiation therapy. However, since existing MR-thermometry techniques do not provide temperature information within the bone, HIFU exposures in bone are currently monitored using temperature changes in adjacent soft tissues. In this study, a standard dual echo spoiled gradient echo (SPGR) sequence is proposed to monitor thermal effects in both bone and soft tissue simultaneously. Magnitude signal changes at the shorter TE (~1ms) reflect thermal changes in cortical bone, while phase changes at the longer TE (~10ms) allow conventional PRF thermometry in surrounding tissues.
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عنوان ژورنال:
دوره 3 شماره
صفحات -
تاریخ انتشار 2015