HYPERSPECTRAL IMAGING AND DATA ANALYSIS OF SKIN ERYTHEMA POST RADIATION THERAPY TREATMENT
| Autor: | ABDLATY, RAMY |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2016 |
| Předmět: | |
| Druh dokumentu: | Diplomová práce |
| Popis: | I DEVELOPED A NEW HIGH THROUGHPUT DUAL CHANNEL HYPERSPECTRAL IMAGING CONFIGURATION BASED ON ACOUSTO-OPTIC TUNABLE FILTER. THE DEVELOPED IMAGING SYSTEM WAS CHARACTERIZED AND EVALUATED IN COMPARISON WITH OTHER CONVENTIONAL CONFIGURATIONS. THE NEW IMAGING SYSTEM PROVED HIGHER THROUGHPUT WITH RESPECT TO THE CURRENTLY USED CONFIGURATIONS.THE IMAGING SYSTEM WAS THEN USED TO QUANTITATIVELY ASSESS AND PRECISELY CLASSIFY SKIN ERYTHEMA INDUCED ARTIFICIALLY ON VOLUNTEERS AND NATURALLY ON SKIN CANCER PATIENTS DUE TO RADIOTHERAPY TREATMENT. Recent cancer statistics show that 40% of Canadians might contract cancer during their life and 25% of Canadians might die due to cancer. In skin, head and neck cancers, surgery and radiation therapies are the most prevalent treatment options, while radiation therapy is the most commonly used approach. A common problem in radiation therapy is tumors behave differently against ionizing radiation. For instance, with the same dose, some tumors are fully damaged or shrunk, while others are less affected. The difference in individual tumor response to therapy is transformed into a research question: how to quantitatively assess tumor response to radiation and how to tune radiation therapy to achieve full destruction for tumor cells? Few past studies addressed the question, although no definite answer was realized. This work is a part of a project that investigates the hypothesis that radiation response of skin is correlated to individual tumor response. In the case of high correlation, the skin’s faster response to ionizing radiation can be used to modify the irradiation dose to achieve the maximum destruction of individual’s tumor. To examine the project hypothesis, radiation-induced skin redness or erythema was selected as an acute skin reaction to being objectively quantified. Hence, the overall goal of the research thesis work is to objectively assess and precisely quantify radiation-induced erythema or radiation dermatitis. Skin erythema was assessed formerly by multiple optical and non-optical modalities. The current gold standard is the visual assessment (VA). Unfortunately, VA lacks objectiveness, precise communication, and quantification. To push the limitations of VA and past techniques, hyperspectral imaging (HSI) was proposed to be used for erythema assessment. The work detailed in this thesis aims to create more confidence in HSI to be utilized toward objectively quantify skin erythema. To reach this goal, initially, a new high-throughput dual channel acousto-optic tunable filter (AOTF)-based-HSI instrument was developed for monitoring radiation dermatitis. AOTF-HSI instrument design, implementation, and full characterization are presented. Second, the developed AOTF-HSI instrument is evaluated against a liquid crystal tunable filter (LCTF) instrument. Third, to be prepared for clinical operation, the AOTF-HSI equipment was used to classify an artificially-induced erythema on healthy volunteers in an exploratory study. A robust linear discriminant analysis (LDA)-based classification method was developed for the purpose of image classification. Finally, HSI instrument and LDA classification method were utilized in a preliminary clinical study to properly monitor and precisely quantify radiation dermatitis for skin cancer patients. In the clinical study, erythema indices were computed using Dawson’s method. Least square fitting was used to fit the acquired absorbance data, and thus quantify the hemoglobin concentration change along the study duration. Moreover, LDA was used to contrast spectral and digital imaging for erythema classification. In sum, the work documented in this thesis was willfully directed to achieve an efficient, portable, user-friendly hyperspectral imaging system which has the opportunity to be a benchtop in the clinical daily procedure in the near future. Thesis Doctor of Philosophy (PhD) |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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