Monitoring tissue response to photodynamic therapy: the potential of minimally invasive electrical impedance spectroscopy and high-frequency ultrasound

Brian C. Wilson; Andrea Molckovsky; G. J. Czarnota; Michael D. Sherar; Mike C. Kolios; Lothar D. Lilge; R. S. Dattani; Kendra Sunshine Osterman; Keith D. Paulsen; P. Jack Hoopes D.V.M.

doi:10.1117/12.351508

6 July 1999 Monitoring tissue response to photodynamic therapy: the potential of minimally invasive electrical impedance spectroscopy and high-frequency ultrasound

Brian C. Wilson, Andrea Molckovsky, G. J. Czarnota, Michael D. Sherar, Mike C. Kolios, Lothar D. Lilge, R. S. Dattani, Kendra Sunshine Osterman, Keith D. Paulsen, P. Jack Hoopes D.V.M.

Author Affiliations +

Proceedings Volume 3592, Optical Methods for Tumor Treatment and Detection: Mechanisms and Techniques in Photodynamic Therapy VIII; (1999) https://doi.org/10.1117/12.351508
Event: BiOS '99 International Biomedical Optics Symposium, 1999, San Jose, CA, United States

Abstract

Electrical impedance spectroscopy (EIS) and high-frequency ultrasound (HFU) have been evaluated in various in vivo and in vitro models as potential methods to monitor biological changes induced by photodynamic therapy (PDT). EIS was assessed in tumor-bearing rat leg in vivo, in multicell tumor spheroids in vitro, and in normal rat liver tissue in vivo. HFU measurements, both imaging and backscatter frequency scanning, were tested in normal rat brain and skin treated in vivo. Marked changes in the EIS spectra were seen in all 3 models following PDT, depending on the photosensitizer and treatment parameters. With HFU, significant increases in echogenicity of the PDT-treated tissues were observed, with evidence of dose dependency and correlation with apoptotic cell death in vivo. While the results are encouraging for both modalities, a number of technical problems remain, particularly in the case of EIS, before these methods can be used reliably in mechanistic and clinical PDT applications.

Citation Download Citation

Brian C. Wilson, Andrea Molckovsky, G. J. Czarnota, Michael D. Sherar, Mike C. Kolios, Lothar D. Lilge, R. S. Dattani, Kendra Sunshine Osterman, Keith D. Paulsen, and P. Jack Hoopes D.V.M. "Monitoring tissue response to photodynamic therapy: the potential of minimally invasive electrical impedance spectroscopy and high-frequency ultrasound", Proc. SPIE 3592, Optical Methods for Tumor Treatment and Detection: Mechanisms and Techniques in Photodynamic Therapy VIII, (6 July 1999); https://doi.org/10.1117/12.351508

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available