Abstract:
:The origin of the differences in the refractive index observed between normal and tumor tissues using terahertz spectroscopy has been described quantitatively. To estimate water content differences in tissues, we prepared fresh and paraffin-embedded samples from rats. An approximately 5% increase of water content in tumor tissues was calculated from terahertz time domain spectroscopy measurements compared to normal tissues. A greater than 15% increase in percentage of cell nuclei per unit area in tumor tissues was observed by hematoxylin and eosin stained samples, which generates a higher refractive index of biological components other than water. Both high water content and high cell density resulted in higher refractive index by approximately 0.05 in tumor tissues. It is predicted that terahertz spectroscopy can also be used to detect brain tumors in human tissue due to the same underlying mechanism as in rats.
journal_name
Phys Med Bioljournal_title
Physics in medicine and biologyauthors
Yamaguchi S,Fukushi Y,Kubota O,Itsuji T,Ouchi T,Yamamoto Sdoi
10.1088/0031-9155/61/18/6808subject
Has Abstractpub_date
2016-09-21 00:00:00pages
6808-6820issue
18eissn
0031-9155issn
1361-6560journal_volume
61pub_type
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