Abstract:
:To generate large thermal lesions in ultrasound thermal therapy, cooling intermissions are usually introduced during the treatment to prevent near-field heating, which leads to a long treatment time. A possible strategy to shorten the total treatment time is to eliminate the cooling intermissions. In this study, the two methods, power optimization and acoustic window enlargement, for reducing power accumulation in the near field are combined to investigate the feasibility of continuously heating a large target region (maximally 3.2 x 3.2 x 3.2 cm3). A multiple 1D ultrasound phased array system generates the foci to scan the target region. Simulations show that the target region can be successfully heated without cooling and no near-field heating occurs. Moreover, due to the fact that there is no cooling time during the heating sessions, the total treatment time is significantly reduced to only several minutes, compared to the existing several hours.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Liu HL,Chen YY,Yen JY,Lin WLdoi
10.1088/0031-9155/48/9/307subject
Has Abstractpub_date
2003-05-07 00:00:00pages
1173-90issue
9eissn
0031-9155issn
1361-6560journal_volume
48pub_type
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