Quantitative analysis of vascular changes during photoimmunotherapy using speckle variance optical coherence tomography (SV-OCT)

Shulian Wu; Ryuhei Okada; Yi Liu; Yuhong Fang; Feng Yan; Chen Wang; Hui Li; Hisataka Kobayashi; Yu Chen; Qinggong Tang

doi:10.1364/BOE.419163

Quantitative analysis of vascular changes during photoimmunotherapy using speckle variance optical coherence tomography (SV-OCT)

Biomed Opt Express. 2021 Mar 2;12(4):1804-1820. doi: 10.1364/BOE.419163. eCollection 2021 Apr 1.

Authors

Shulian Wu^{1

2

3}, Ryuhei Okada^{4

3}, Yi Liu², Yuhong Fang¹, Feng Yan⁵, Chen Wang⁵, Hui Li¹, Hisataka Kobayashi^{4

6}, Yu Chen^{1

2

7

8}, Qinggong Tang^{2

5

9}

Affiliations

¹ College of Photonic and Electronic Engineering, Fujian Provincial Engineering Technology Research Center of Photoelectric Sensing Application, Fujian Provincial Key Laboratory of Photonic Technology, Key Laboratory of Optoelectronic Science and Technology for Medicine, Ministry of Education, Fujian Normal University, Fuzhou, 350007, China.
² Fischell Department of Bioengineering, University of Maryland, College Park, MD 20742, USA.
³ These authors contributed equally to this work.
⁴ National Institute of Health, National Cancer Institute, Molecular Imaging Program, Bldg 10, Room B3B47, Bethesda, Maryland 20892-1088, USA.
⁵ Stephenson School of Biomedical Engineering, University of Oklahoma, Norman, OK 73019, USA.
⁶ kobayash@mail.nih.gov.
⁷ Department of Biomedical Engineering, University of Massachusetts, Amherst, MA 01003, USA.
⁸ ychen8@umass.edu.
⁹ qtang@ou.edu.

Abstract

Near-infrared (NIR) photoimmunotherapy (NIR-PIT) is an emerging cancer therapy based on a monoclonal antibody and phthalocyanine dye conjugate. Direct tumor necrosis and immunogenic cell death occur during NIR irradiation. However, the alteration of tumor blood vessels and blood volume inside the blood vessels induced by the NIR-PIT process is still unknown. In our study, a speckle variance (SV) algorithm combined with optical coherence tomography (OCT) technology was applied to monitor the change of blood vessels and the alterations of the blood volume inside the blood vessels during and after NIR-PIT treatment. Vascular density and the measurable diameter of the lumen in the blood vessel (the diameter of the region filled with blood) were extracted for quantitively uncovering the alterations of blood vessels and blood volume induced by NIR-PIT treatment. The results indicate that both the density and the diameter of the lumen in the blood vessels decrease during the NIR-PIT process, while histological results indicated the blood vessels were dilated. The increase of permeability of blood vessels could lead to the increase of the blood pool volume within the tumor (shown in histology) and results in the decrease of free-moving red blood cells inside the blood vessels (shown in SV-OCT).