Chromophore selective multi-wavelength photoacoustic remote sensing of unstained human tissues

Saad Abbasi; Martin Le; Bazil Sonier; Kevan Bell; Deepak Dinakaran; Gilbert Bigras; John R Mackey; Parsin Haji Reza

doi:10.1364/BOE.10.005461

Chromophore selective multi-wavelength photoacoustic remote sensing of unstained human tissues

Biomed Opt Express. 2019 Oct 1;10(11):5461-5469. doi: 10.1364/BOE.10.005461. eCollection 2019 Nov 1.

Authors

Saad Abbasi^{1

2}, Martin Le^{1

2}, Bazil Sonier¹, Kevan Bell^{1

3}, Deepak Dinakaran^{3

4}, Gilbert Bigras⁵, John R Mackey⁴, Parsin Haji Reza¹

Affiliations

¹ PhotoMedicine Labs, Department of Systems Design Engineering, University of Waterloo, Waterloo, Ontario, N2L 3G1, Canada.
² Equal contributions.
³ illumiSonics, Inc., Department of Systems Design Engineering, University of Waterloo, Waterloo, Ontario, N2L 3G1, Canada.
⁴ Department of Oncology, University of Alberta, Edmonton, Alberta, T6G 2V1, Canada.
⁵ Department of Laboratory Medicine and Pathology, University of Alberta, Edmonton, Alberta, T6G 2V1, Canada.

Abstract

Identifying positive surgical margins after resection of cancer often triggers re-excision and adjuvant treatments. Incomplete initial resections result in poorer patient outcomes, psychological and financial stress to the patient and increased healthcare costs. Surgical margins are typically assessed post-operatively using time consuming and expensive slide-based histopathology tissue analysis. Currently, a real-time non-contact virtual histology-like intraoperative margin assessment tool is not available. To address this need, we have developed a non-contact multi-wavelength reflection-mode, photoacoustic remote sensing (PARS) microscope demonstrating chromophore selective contrast in human tissues. We show the capabilities of multi-wavelength PARS microscopy utilizing both 266 nm and 532 nm excitation wavelengths and a 1310 nm detection wavelength. Cell nuclei and hemoglobin were visualized at the cellular scale without the addition of exogenous contrast agents. These works provide a critical step towards a virtual histology tool to provide intraoperative histology-like information in living tissue.