Multispectral photoacoustic tomography for detection of small tumors inside biological tissues

Takeshi Hirasawa; Shinpei Okawa; Kazuhiro Tsujita; Toshihiro Kushibiki; Masanori Fujita; Yasuteru Urano; Miya Ishihara

doi:10.1117/12.2293438

Translator Disclaimer

19 February 2018 Multispectral photoacoustic tomography for detection of small tumors inside biological tissues

Takeshi Hirasawa, Shinpei Okawa, Kazuhiro Tsujita, Toshihiro Kushibiki, Masanori Fujita, Yasuteru Urano, Miya Ishihara

Author Affiliations +

Proceedings Volume 10494, Photons Plus Ultrasound: Imaging and Sensing 2018; 104943M (2018) https://doi.org/10.1117/12.2293438
Event: SPIE BiOS, 2018, San Francisco, California, United States

Abstract

Visualization of small tumors inside biological tissue is important in cancer treatment because that promotes accurate surgical resection and enables therapeutic effect monitoring. For sensitive detection of tumor, we have been developing photoacoustic (PA) imaging technique to visualize tumor-specific contrast agents, and have already succeeded to image a subcutaneous tumor of a mouse using the contrast agents. To image tumors inside biological tissues, extension of imaging depth and improvement of sensitivity were required. In this study, to extend imaging depth, we developed a PA tomography (PAT) system that can image entire cross section of mice. To improve sensitivity, we discussed the use of the P(VDF-TrFE) linear array acoustic sensor that can detect PA signals with wide ranges of frequencies. Because PA signals produced from low absorbance optical absorbers shifts to low frequency, we hypothesized that the detection of low frequency PA signals improves sensitivity to low absorbance optical absorbers. We developed a PAT system with both a PZT linear array acoustic sensor and the P(VDF-TrFE) sensor, and performed experiment using tissue-mimicking phantoms to evaluate lower detection limits of absorbance. As a result, PAT images calculated from low frequency components of PA signals detected by the P(VDF-TrFE) sensor could visualize optical absorbers with lower absorbance.

Citation Download Citation

Takeshi Hirasawa, Shinpei Okawa, Kazuhiro Tsujita, Toshihiro Kushibiki, Masanori Fujita, Yasuteru Urano, and Miya Ishihara "Multispectral photoacoustic tomography for detection of small tumors inside biological tissues ", Proc. SPIE 10494, Photons Plus Ultrasound: Imaging and Sensing 2018, 104943M (19 February 2018); https://doi.org/10.1117/12.2293438

ACCESS THE FULL ARTICLE