Dissertation

Optimizing an Elastic Scattering Spectroscopy Scanning Device for Clinical Measurements of Deep Tissue Margins in Oral Cavity

Chung, Ji Young

2024

Overview

Approximately 58,000 Americans were diagnosed with oral cancer in 2022, and it has a high mortality rate of approximately 47%. 90% of these oral cancer cases have been confirmed to be squamous cell carcinoma, while oral malignant melanoma and adenocarcinomas are less-common types. Part of the reason for the lethality of this disease is late discovery at the advanced stages when diagnosed, showing the importance of identifying tumors or dysplastic cells in the early stages. Due to the high recurrence rate of oral cancer, complete surgical removal of the tumor is required. The current gold standard for the analysis of removed margins is Frozen Section analysis (FS), which is both time-consuming and is limited by significant sampling error. Due to the inability to assess the entire resection margin histologically, proper guidance for the surgical margin of specimen selection is needed. Elastic Scattering Spectroscopy (ESS) is an optical technique that measures backscattered spectra using fiber optics and can detect optical characteristics of the tissue without damaging it. ESS is a point measurement technique, and recent studies in the Bigio lab developed an ESS scanning module that combines an ESS system with a tissue scanning module, enabling a series of measurements in a target area of the tissue, with step sizes of 100 micrometers to 1 mm. However, the current scanning module has drawbacks for practical usage in the clinic: the stability of scanning functions is low; the height of an ESS probe cannot be adjusted precisely; the LED array interrupts ESS measurement; and there is inadequate optical contact between the ESS probe and the fiber optic plate (FOP) upon which the tissue sample is placed. The goal of this project is to further optimize the scanning module in order to remove malfunctions of the ESS software, provide a stable mechanical environment and increase the measurement speed, improve optical contact for quantitative ESS measurements, and build a protocol for assessing the deep margin of oral cancer tumors. The optimized module has been developed to measure quantitative spectral data that co-registers with a photograph of the scanned tissue. A device demo has successfully obtained the data from 10mm x 10mm boundary inked hotdog following the protocol developed in this thesis.

• Publisher: ProQuest Dissertations & Theses
• Subject: Biomedical engineering / Canadian history / Optics
• ISBN: 9798382747774