Title :
Attenuation mapping for monitoring thermal therapy using ultrasound transmission imaging
Author :
Parmar, N. ; Kolios, M.C.
Author_Institution :
Dept. of Electr. & Comput. Eng., Ryerson Univ., Toronto, Ont., Canada
Abstract :
The use of an ultrasound (US) transmission imaging system to monitor attenuation changes during tissue heating was investigated. This work presents preliminary results of images obtained from an acoustic camera before, during and after heating tissue phantoms using a heated needle. Two types of tissue-mimicking phantoms were used, agar and polyacrylamide-based. Regions of interests were chosen in images obtained from the real-time imaging system, and the pixel intensity values before, during and after heating were compared. In both phantoms, a decrease in image intensities was observed during heating, indicating an increase in tissue attenuation. Additionally, an irreversible change in image intensity was observed in regions close to the heat source. The reversibility of the intensity change was shown to be a function of the distance from the heating needle to the selected region. Initial results indicate that US transmission imaging can be used to monitor thermal therapy.
Keywords :
biological tissues; biomedical ultrasonics; patient monitoring; patient treatment; phantoms; ultrasonic absorption; acoustic camera; agar phantom; heat source; heated needle; image intensity; polyacrylamide-based phantom; real-time imaging system; thermal therapy monitoring; tissue attenuation mapping; tissue phantom heating; tissue-mimicking phantoms; ultrasound transmission imaging; Acoustic imaging; Attenuation; Cameras; Heating; Imaging phantoms; Medical treatment; Monitoring; Needles; Real time systems; Ultrasonic imaging; Attenuation; Thermal therapy; Ultrasound; Ultrasound transmission imaging;
Conference_Titel :
Engineering in Medicine and Biology Society, 2004. IEMBS '04. 26th Annual International Conference of the IEEE
Conference_Location :
San Francisco, CA
Print_ISBN :
0-7803-8439-3
DOI :
10.1109/IEMBS.2004.1403417