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AN ABSTRACT OF THE THESIS OF
Kamal Fouad Bichara for^ the^ degree^ of^ Doctor^ of^ Philosophy Electrical and in Computer Engineering presented^ on
Title: LIQUID CRYSTAL THERMOGRAPHY: A^ NEW^ SYSTEM^ FOR
BREAST CANCER DETECTION
Abstract approved:
Redactedforprivacy
Dr. C. C. Chang
A liquid crystal thermographic technique was devel- oped for application to several problems in clinical medicine and physiology. The^ procedure^ was^ inexpensive, rapid, simple, versatile and acceptable to patients. Investigators in the past have used cholesteric liquid crystals for thermography but their use was limited to research in the medical field because the methods involved called for the direct spraying of the skin surface with the liquid crystals over a black paint. The present research has been involved in the development and fabrication of a liquid crystal dispersion thin film with very high elastomeric properties which pro- vides perfect contact with the skin surface of a body of
any configuration. Different^ films^ were^ prepared^ using plasticized vinyl resins in which the liquid crystals are dispersed. The final film yields optimum optical, thermal and mechanical characteristics and a long shelf life. Liquid crystal dispersions in plasticized polyvinyl chloride or copolymers of vinyl chloride and vinyl acetate were fabricated. However,^ polyvinyl^ butyral^ was^ selected since it forms strong, highly resilient films and yields optimum optical characteristics. After the film was perfected, a clinical compara- tive study was conducted to evaluate the new system. In this study, seventy-five volunteer women were given a breast examination using three modalities: (1) Liquid^ crystal^ thermography^ using^ the^ thin film. (2) Liquid^ crystal^ thermography^ using^ the^ direct spraying of the liquid crystals over a pre-blackened coat (Trade name--Lix Kit). (3) Infrared^ thermography^ using^ AGA^ Thermovision model 680 infrared thermography system. All positively read thermograms were followed up by a xeroradiography examination, the most recent and widely spread method for breast cancer detection. Positive thermographic signs were defined and a new interpretation scheme was introduced intended to reduce the
Liquid Crystal Thermography: A^ New^ System for Breast Cancer Detection
by Kamal Fouad Bichara
A THESIS
submitted to Oregon State University
in partial fulfillment of the requirements for the degree of Doctor of Philosophy Completed August 16, 1975 Commencement June 1976
APPROVED:
Redactedforprivacy
Assistant Professor of Eleg_trIcal and Computer Engineering in charge of major
Redactedforprivacy
Head of Department of Electrical and Computer Engineering
Redactedforprivacy
Dean of Gr-aduat9iSchbol
Date thesis is presented //(>, /925'
Miss Joanne Bonish, R.N., for her assistance and the long hours she put in the clinical study that made the comple- tion of this work possible.
TABLE OF CONTENTS
VI. Results^ and^ Discussion:^ Part^ III-
- I. Introduction - Definition - Liquid Crystal Thermography Characteristics - How the Study Was Done - The Liquid Crystal Phenomenon - Anisotropism of Crystalline Solids - Isotropism of Liquids - Molecular Arrangement in a Liquid Crystal - Crystals Optical Properties of Cholesteric Liquid - II. Literature Review - History of Thermography - Thermography in Breast Cancer Detection - Principle Xeroradiography of Surface Temperature Mapping - in Tumor Detection
- III. Experimental Fabrication Procedure Criteria and Properties of - Film Layers - Fabrication Procedure - Analysis of Film Properties - Stability Considerations - Optical Methods, Properties Materials, and Protocol for Breast - Three Modalities Cancer Screening Using Thermography in - Comparative Study IV. Results and Discussion: Part I -- - A. Sample Description - B. Factors Affecting Thermograms - Thermographic Evaluation - Interpretation Scheme V. Results and Discussion: Part II -- - The Abnormal Thermogram - Interpretation Scheme The Clinical Evaluation of the
- VII. Conclusions and Suggestions - Bibliography
Figure Page
- Effect^ of^ adding^ CBz^ on^ characteristics of^ a 50/50 OCC-CN system 55
- Effect of concentration on viscosity of P.V.A. 57
- Polyvinyl^ butyral^ viscosity^59
- Filtering^ characteristics^ of^ packaged liquid crystal films 65
- Stability^ results^ for^ control^ and^ normally exposed sample 67
- Effect of film thickness on reflected light^68
- Breast^ temperature^ range^ histogram^80
- Breast controlled^ temperature ambient^ rangetemperature^ histogram under 80
- Liquid^ crystal^ thermograms^ showing (a) vascular^ thermogram (b) avascular thermogram (c) mottled thermogram
- Liquid^ crystal^ thermogram (a) patient^ in^ the^ supine^ position (b) patient^ in^ the^ sitting^ position
- Comparative^ thermograms (a) liquid^ crystal^ elastic^ film (b) liquid^ crystal^ direct^ spraying (c) Infrared
- Comparative (a) liquid^ thermogramcrystal elastic^ of^ a^ normalfilm^ pattern (b) liquid^ crystal^ direct^ spraying (c) infrared
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88
89
92
- Diagram^ of^ the^ breast^ section^97
- Liquid heat associated^ crystal^ thermogram with an avascular^ illustratingpatternfocal 99
Figure Page
- Liquid crystal thermogram illustrating a case of fibrocystic disease showing an increase in heat confined to a single vein 100
- (^) Liquid crystal thermogram illustrating a case of diffuse heat
- Comparative thermogram showing a case with unilateral vascularity radiating from the left areola (a) liquid crystal elastic film (b) liquid crystal direct spraying (c) infrared
- Comparative thermogram showing a case with unilateral medial vascularity of the left breast (a) liquid crystal elastic film (b) liquid^ crystal^ direct^ spraying (c) infrared
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107
- Age distribution of 1000 cases 111
- Xerogram and corresponding infrared thermogram of a case with a large carcinoma in the subareolar region of the left breast 116
- Xerogram and corresponding infrared thermogram of a case of carcinoma within the upper and lateral quadrant of left breast
- Xerogram and corresponding infrared thermogram of a case of carcinoma in the subareolar area of the left breast
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- Xerogram^ and^ corresponding^ infrared^ thermogram of a case of carcinoma of the right breast 120
LIQUID CRYSTAL THERMOGRAPHY: A NEW SYSTEM
FOR BREAST CANCER DETECTION
I. INTRODUCTION
Definition
Thermography is the technique of photographically portraying the surface temperature of a body. The^ optimum thermographic technique provides a quantitative, instanta- neous thermogram equivalent to the maximum possible number of individual temperature measurements per unit area. Therefore, the criteria of an optimum thermogram is both a high temperature sensitivity and spatial resolution in real time. In the clinical comparative study, Xeroradiography is used as a follow-up method on all volunteers with posi- tively read thermograms. Xeroradiography^ is^ the^ use^ of^ a modified X-ray irradiation technique for the distinction between normal and abnormal tissues. Liquid Crystal Thermography Characteristics Liquid crystal (L.C.) thermography is a relatively new technique that provides many of the optimal character- istics desired in thermography. L.C.^ thermography^ was
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developed by utilizing the color temperature properties of cholesteric liquid crystals. When^ applied^ over^ a^ blackened surface, cholesteric liquid crystals give rise to irides- cent colors, the dominant wavelength being influenced by a very small temperature change. L.C. thermography is cap- able of producing a color thermogram with a temperature sensitivity of 0.1°C and a spatial resolution of 1000 lines per inch. A major advantage of L.C. thermography over other techniques is that it may be viewed in real time since no scan is required. The time constant observed in L.C. thermograms is 0.1 second (Fergason, 1968); a significant factor for dynamic thermographic applications. The L.C. thermographic technique utilizes mixtures of cholesteric liquid crystal materials that display color- temperature properties when applied in a thin layer over a blackened skin surface. A typical material used for medical and physiological applications responds with a 4°C color-temperature range; however, the range can be varied depending on the cholesteric esters used and their relative proportions. All colors of the visible spectrum are seen on the L.C. thermogram with shades of blue, green and red being most dominant on simple observation. The^ highest temperatures on the thermogram are shades of blue, the low- est temperatures are shades of red and the intermediate are
is protected against degradation right up to the moment of application. The solution, once cast, is very vulnerable to degradation from oxygen and UV light as it is totally exposed. Fergason (1968) quotes a lifetime of 3-4 hours before the performance is impaired. (b) Re-use of cholesteric liquid crystal formu- lation is only possible by scraping off the solution and reconstitution in a solvent. (c) The surface to which the cholesteric liquid crystal solution is applied must be free from grease, oil and fat traces which can depress the color-temperature play for a temperature sensitive system. (d) Unless formulation containing built-in blackening material is used, the surface must first be coated with a water-soluble black paint, a process which is not well accepted in medical practice. In addition, time has to be allowed for evaporation of solvents.
(e) In^ order^ to^ maximize^ the^ intensity^ of^ the colors observed, the cholesteric liquid crystal solution should be orientated in the plane texture by mechanical disturbance to convert the focal-conic texture to the plane texture as reported by Gray (1962) and Adams (1969). (f) It is not possible to obtain a perfectly uniform film.
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(2) Importance of early breast cancer detection It has been reported that successful treatment of breast cancer by mastectomy and radiotherapy depends sig- nificantly upon its stage of development at detection. If metastasis has not occurred beyond the axillary lymph nodes, the cancer may be completely ablated (Aartz, 1967). Self-examination has been recommended. However, Gershon-Cohen, et al. (1970) stated that self-examination should not be decried, but that in advocating this approach, we are, in effect, making the woman responsible for dis- covering her own cancer. Women do discover their own cancer in 95% of the cases. (^) Cancers are then found large and late. (^) They average 3.5 cm in diameter and have metastasized in about 65% of the cases by the time surgery is performed. (^) The five-year survival rate in these circum- stances is about 45-50%. In contrast, when the physicians assume responsibility for finding evidence of breast cancer by periodic examination aided by such procedures as ther- mography, mammography or xeroradiography, lesions are found to average 1.0 cm in diameter and to be associated with metastases in only 30% of the cases. About 80% of women with the early, Stage 1 lesions will attain a survival rate of five years or longer. It was shown that breast cancer grows on a linear scale from the time of clinical recogni- tion until terminal acceleration in the phases of
5 ni tz 0
4-1 0 a) 5 0
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Metastasis beyond axilla begins
adenopathy begins localized
Occult disease
(^6 ) Duration of Disease
10 (Years)
Dissemination
Incurable
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Figure 1. Natural history of untreated mammary carcinoma (After Delarue 1969)
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have screened large numbers of women with and without sus- picious breast characteristics using infrared (IR) ther- mography. The IR scanner picks up the emission of infrared radiation from the skin. The^ infrared^ emission^ is^ propor- tional to the fourth exponent of the absolute temperature. A thermal pattern is recorded as a permanent black and white or color scan. Thermography^ is^ given^ priority^ when other techniques show no evidence for carcinoma (Gershon- Cohen et al., 1970; 1971). Though^ IR^ thermography^ proved its effectiveness in breast cancer screening, its applica- tion for diagnosis and screening is limited due to unavailability as a result of high instrumentation costs. (5) Some^ investigators^ in^ the^ field^ using^ IR thermography Isard (1974) showed their concern about the inconstancy of the IR thermographic diagnosis when read by different radiologists, a major factor in the accuracy of interpretation. This^ necessitated^ the^ development^ of^ a systematic interpretation scheme which applies for L.C. and IR thermography. The inexpensive, simple and rapid liquid crystal thermographic technique developed in this study offers an answer to the unavailability of thermography in^ most hospitals and clinics. The^ development^ of^ the^ thin^ elastic film technology was undertaken to correct the lack of a reliable and easily available method for early detection of
