TY - JOUR
T1 - Statistical Analysis of Ultrasonic Scattered Echoes Enables the Non-invasive Measurement of Temperature Elevations inside Tumor Tissue during Oncological Hyperthermia
AU - Takeuchi, Michio
AU - Sakai, Toshihiko
AU - Andocs, Gabor
AU - Takanaka, Tsuyoshi
AU - Taka, Masashi
AU - Yamashita, Kuniko
AU - Kawahara, Masahiro
AU - Nojiri, Tomoko
AU - Tanaka, Asaka
AU - Norishima, Azusa
AU - Omoto, Yoshitaka
AU - Omura, Masaaki
AU - Nagaoka, Ryo
AU - Takao, Keizo
AU - Hasegawa, Hideyuki
N1 - Publisher Copyright:
© 2021 The Authors
PY - 2021/11
Y1 - 2021/11
N2 - Non-invasive monitoring of temperature elevations inside tumor tissue is imperative for the oncological thermotherapy known as hyperthermia. In the present study, two cancer patients, one with a developing right renal cell carcinoma and the other with pseudomyxoma peritonei, underwent hyperthermia. The two patients were irradiated with radiofrequency current for 40 min during hyperthermia. We report the results of our clinical trial study in which the temperature increases inside the tumor tissues of patients with right renal cell carcinoma and pseudomyxoma peritonei induced by radiofrequency current irradiation for 40 min could be detected by statistical analysis of ultrasonic scattered echoes. The Nakagami shape parameter m varies depending on the temperature of the medium. We calculated the Nakagami shape parameter m by statistical analysis of the ultrasonic echoes scattered from the tumor tissues. The temperature elevations inside the tumor tissues were expressed as increases in brightness on 2-D hot-scale maps of the specific parameter αmod, indicating the absolute values of the percentage changes in m values. In the αmod map for each tumor tissue, the brightness clearly increased with treatment time. In quantitative analysis, the mean values of αmod were calculated. The mean value of αmod for the right renal cell carcinoma increased to 1.35 dB with increasing treatment time, and the mean value of αmod for pseudomyxoma peritonei increased to 1.74 with treatment time. The increase in both αmod brightness and the mean value of αmod implied temperature elevations inside the tumor tissues induced by the radiofrequency current; thus, the acoustic method is promising for monitoring temperature elevations inside tumor tissues during hyperthermia.
AB - Non-invasive monitoring of temperature elevations inside tumor tissue is imperative for the oncological thermotherapy known as hyperthermia. In the present study, two cancer patients, one with a developing right renal cell carcinoma and the other with pseudomyxoma peritonei, underwent hyperthermia. The two patients were irradiated with radiofrequency current for 40 min during hyperthermia. We report the results of our clinical trial study in which the temperature increases inside the tumor tissues of patients with right renal cell carcinoma and pseudomyxoma peritonei induced by radiofrequency current irradiation for 40 min could be detected by statistical analysis of ultrasonic scattered echoes. The Nakagami shape parameter m varies depending on the temperature of the medium. We calculated the Nakagami shape parameter m by statistical analysis of the ultrasonic echoes scattered from the tumor tissues. The temperature elevations inside the tumor tissues were expressed as increases in brightness on 2-D hot-scale maps of the specific parameter αmod, indicating the absolute values of the percentage changes in m values. In the αmod map for each tumor tissue, the brightness clearly increased with treatment time. In quantitative analysis, the mean values of αmod were calculated. The mean value of αmod for the right renal cell carcinoma increased to 1.35 dB with increasing treatment time, and the mean value of αmod for pseudomyxoma peritonei increased to 1.74 with treatment time. The increase in both αmod brightness and the mean value of αmod implied temperature elevations inside the tumor tissues induced by the radiofrequency current; thus, the acoustic method is promising for monitoring temperature elevations inside tumor tissues during hyperthermia.
KW - Nakagami shape parameter
KW - Non-invasive temperature measurement
KW - Oncological hyperthermia
KW - Statistical analysis
KW - Ultrasonic scattered echoes
UR - http://www.scopus.com/inward/record.url?scp=85113358495&partnerID=8YFLogxK
U2 - 10.1016/j.ultrasmedbio.2021.07.019
DO - 10.1016/j.ultrasmedbio.2021.07.019
M3 - 学術論文
C2 - 34446333
AN - SCOPUS:85113358495
SN - 0301-5629
VL - 47
SP - 3301
EP - 3309
JO - Ultrasound in Medicine and Biology
JF - Ultrasound in Medicine and Biology
IS - 11
ER -