TY - JOUR
T1 - Prototype dual frequency bilaminar array transducer capable of therapeutic exposure at 500 kHz and doppler monitoring at 2MHz
AU - Azuma, Takashi
AU - Umemura, Shin Ichiro
AU - Ogiliara, Makoto
AU - Kubota, Jun
AU - Kobayashi, Takashi
AU - Izumi, Mikio
AU - Sasaki, Akira
AU - Furuhata, Hiroshi
PY - 2004
Y1 - 2004
N2 - It is known that ultrasound can enhance thrombolysis with tissue plasminogen activator (tPA). A blood flow monitoring is required for an optimum control of the tPA injection and the therapeutic sonication. In order to transmit ultrasonic waves at two frequencies, one for imaging and the other for therapy, from the same aperture, we proposed a probe consisting of a therapeutic array with an imaging array overlaid on it. Between these two arrays, a frequency selective isolation layer was inserted to ensure independent oscillatory motions of the two arrays. The function of this layer is expected to reflect the waves from the imaging array and allow the waves from the therapeutic array to pass through. A prototype sector array transducer was designed and constructed based on numerical simulation. B-mode and color flow images of human brains obtained with the prototype were comparable to those of conventional structure transducers with respect to sensitivity and resolution. Schlieren images showed that the sidelobe levels of the therapeutic beam were less than -20 dB when steering angle was limited to 45 degrees in each direction.
AB - It is known that ultrasound can enhance thrombolysis with tissue plasminogen activator (tPA). A blood flow monitoring is required for an optimum control of the tPA injection and the therapeutic sonication. In order to transmit ultrasonic waves at two frequencies, one for imaging and the other for therapy, from the same aperture, we proposed a probe consisting of a therapeutic array with an imaging array overlaid on it. Between these two arrays, a frequency selective isolation layer was inserted to ensure independent oscillatory motions of the two arrays. The function of this layer is expected to reflect the waves from the imaging array and allow the waves from the therapeutic array to pass through. A prototype sector array transducer was designed and constructed based on numerical simulation. B-mode and color flow images of human brains obtained with the prototype were comparable to those of conventional structure transducers with respect to sensitivity and resolution. Schlieren images showed that the sidelobe levels of the therapeutic beam were less than -20 dB when steering angle was limited to 45 degrees in each direction.
UR - http://www.scopus.com/inward/record.url?scp=21644469245&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=21644469245&partnerID=8YFLogxK
M3 - Conference article
AN - SCOPUS:21644469245
VL - 1
SP - 141
EP - 144
JO - Proceedings - IEEE Ultrasonics Symposium
JF - Proceedings - IEEE Ultrasonics Symposium
SN - 1051-0117
T2 - 2004 IEEE Ultrasonics Symposium
Y2 - 23 August 2004 through 27 August 2004
ER -