thermogram-interpretation

Breast Thermography Evaluation ― Technical Foundation

The TAS proprietary Breast Thermography Evaluation computer program, authored by Edward B. Jay, is based on the methodology and protocol of 'Micro-Thermology's CBT Test,' developed several years ago by Jay when a principal of that company. It was used successfully by Thermal Assessment Laboratories to objectively evaluate thousands of thermograms. The following is a reprint, in part, of Jay's co-authored paper. (Deleted for brevity is the section on Examination Protocol, discussed at length elsewhere on this site.)

 

Computerized breast thermography (CBT) Test

E. B. JAY and H. L. KARPMAN
 
THE BREAST CANCER DEBACLE - A CIRCUS OF CONFUSION AND CONTROVERSY

Early detection is currently the only possible hope for improving the survival rate of breast cancer patients. Although advances in medical technology have significantly contributed to the detection and diagnosis of small, non-palpable cancerous lesions, these successes of the past 40 years have proven inadequate since the mortality rate for breast cancer patients has remained unchanged for almost half a century. The reasons for failing to effect a solution to the problem result from a circus of confusion and controversy.


Insufficient and inappropriate patient education has often been cited as a principal reason for static mortality. Educational campaigns successful in conveying the dangers of breast cancer have failed miserably to communicate the benefits associated with early detection. Early detection of breast cancer has incorrectly become synonymous with doom prediction. Shock, concern, worry and fear are common reactions when a woman discovers she may have the disease, and delays in seeking proper medical care are not uncommon, even for symptomatic women. The American female population has been frightened to inaction.


Women have incorrectly been taught that early detection of breast tumours with a significantly improved prognosis for breast cancer can be achieved by breast self-examination (BSE) alone. Properly performed BSE may result in early detection of breast cancer and is therefore an important procedure to be practised by every adult woman; however, it should not be relied upon as the primary solution to the early breast cancer problem. The most favourable prognosis in breast cancer occurs when tumours are detected while they are still in their early stages which, on the average, occurs years before they become palpable. By the time a mass is large enough to be palpated, it is usually 8 years old or older, and has grown to a diameter of 1-4 cm, it may be malignant, or worse, it may have metastasized. Although BSE has been effective in bringing more symptomatic women to seek medical attention, quite frequently it has been ineffective in detecting the cancer early enough for successful treatment. Consequently, most women have been conditioned to believe that a diagnosis of breast cancer is a sentence of death preceded by physical mutilation and psychological devastation, even when detected early.


Major technological advances in medical diagnostic techniques have had little, or no impact on the breast cancer survival rate. X-Ray mammography, in particular, has been shown to be effective in detecting subpalpable lesions, yet overall mortality has not improved. The hazards of radiation and the uncertainty of benefits from mammography are still the object of public debate, controversy and confusion; as a result, patients are reluctant to agree to the procedure. A recent example illustrates a reason for this poor attitude. In July, 1983 the American Cancer Society publicly announced modification of its 'Cancer-Related Checkup Guidelines' for breast cancer detection, recommending that asymptomatic women aged 40-49 years routinely undergo mammography at intervals of 1-2 years. Their major news campaign was predictably followed by many critical responses, from within the medical community as well as from the media.


These events have sadly produced the current situation in which less than 45% of the mammograms prescribed for symptomatic women are actually performed! X-Ray mammography is feared and rejected by many women because of the exposure to potentially dangerous radiation and because many authorities question a procedure which inherently must have both false-positive and false-negative results. Until these notions are dispelled, mammography will remain unacceptable for use in screening large numbers of asymptomatic patients.


The ultimate responsibility for providing the highest level of health care rests with the primary-care physician since the overwhelming majority of routine physical examinations are performed by this group. However, the majority of primary-care physicians and even board certified gynaecologists do not include examination of the breasts in their routine physical examinations. The medical profession cannot be held completely responsible for this apparent abandonment of fundamental medical responsibility, since physicians have not, until recently, been provided with adequate education regarding breast examinations and completely accurate diagnostic methodologies have not been available for use by the medical profession.


There is little hope of improving the survival rate of breast cancer patients unless all of the previous causes for failure are identified and eliminated. Effective detection and diagnostic techniques must be made available to the general population and women must be educated to trust and take advantage of each new and improved technique. A successful educational campaign must do more than dispel the fears of women; it must condition them to welcome early detection as beneficial to their personal health, develop confidence in the medical establishment, and encourage them to follow the prescribed recommendations of their personal physicians. The attitudes of women will change; but first, they must be given adequate reasons for changing them.


THE CBT TEST - SAFE, ACCURATE AND PATIENT ACCEPTED

The CBT Test is a significant improvement for early detection of breast disorders. It is a safe, non-invasive routine procedure that consists of breast thermograms recorded pursuant to a strict examination protocol and evaluated by a proven objective interpretation procedure utilizing Micro-Thermology's proprietary computerized system.


Published data clearly indicate that the CBT Test satisfies many of the requirements perceived necessary to favourably affect the overall mortality of breast cancer. The Test has repeatedly demonstrated its capability as a marker of symptomatic women at high risk for developing breast cancer and prospective tests currently underway in university centres are designed to confirm previously published reports which demonstrate the benefit of thermography in screening asymptomatic women who are at similar risk. Extensive clinical trials have shown that thermal breast assessment, as performed in the CBT Test significantly augments the long-term survival rates of its recipients by as much as 61%. As a functional test of the biological condition of breasts, its capabilities are unsurpassed. It is a safe, non-invasive technique that has quickly achieved patient acceptance as an easy-to-per-form, cost-effective and routine procedure. The equipment required to perform the Test is inexpensive, making it available to all physicians. The CBT Test is a significant improvement in breast thermography methodology and its ability to screen symptomatic patients for breast cancer has repeatedly been demonstrated. The prospective study currently in progress to verify the efficacy of the CBT Test for screening asymptomatic patients may result in the Test being as common as the PAP test within 3-5 years.


The CBT Test was designed with several purposes in mind. First, and most important, to identify patients at high risk for developing breast cancer. Second, to aid in the early detection of biological changes in the breast that, on many occasions, may precede the advanced manifestations of breast cancer; and third, to assist in the functional evaluation of both the normal and the abnormal breast. The CBT Test is a serial procedure which should routinely be performed with the annual physical or gynaecological examination. Early detection of possible pathology is aided by correlating CBT Test results with other diagnostic findings, especially with the results of previous CBT Tests.


The CBT Test does not identify specific pathology; it serves as a functional test of the breasts' biological status and should be used only as an adjunct to other methods of breast examination including physical examination, mammography and/or biopsy. The Test is an indicator of possible breast pathology, but other tests, such as mammography and/or diaphanography must also be used to further identify and locate the disorder.


To obtain maximum benefit from the CBT Test, women should undergo their first Test as soon as possible after the thermal characteristics of their (normal) breasts have become stable with respect to the patient's age (this typically occurs by age 27). If the CBT Test is positive, clinical correlation is indicated and, if appropriate, additional diagnostic studies as suggested in the CBT Test report should be considered. The second CBT Test is performed at age 30, at which time many authorities also recommend a baseline mammogram. Subsequent CBT Tests should be routinely performed at least annually.


A baseline mammogram should be considered at age 30, especially if the first CBT Test is positive. The second CBT Test should be performed 3-6 months after the first if abnormal thermobiological patterns are present in the first study, in order to be sure these are stable patterns.


The unique capabilities of the CBT Test provide the ideal foundation from which to rebuild patient confidence in early detection of breast disorders. This is needed because women are confused and confounded by past educational campaigns which have, not infrequently, conditioned women to fear early detection of breast pathology. The CBT Test is an ideal supplement to the primary-care physician or gynaecologist's practice. It provides the clinician with the necessary methodology to assure patients the best available breast health care by aiding in the early detection of breast pathology.


Women fear early discovery of breast cancer and they feel justified in their fear of mammography. Because of its safety, proven efficacy and patient acceptability, the CBT Test provides an excellent method whereby these fears may be dispelled.


THERMOGRAPHY - AN OLD TECHNIQUE WHICH FINALLY HAS COME OF AGE!

Thermography is a passive, non-invasive technique by which the temperature variations of adjacent skin surfaces are measured and recorded. The surface temperature of the skin is dependent upon heat transferred from underlying tissues or organs and the thermogram, or photograph of the 'thermal patterns' of the breasts, can provide a graphic method of recording possible breast abnormalities or diseases. Recorded and analysed properly, thermography may make a significant contribution to the overall evaluation of patients suspected of having breast cancer, and equally important, to the early diagnosis of breast cancer, since the abnormal thermogram in asymptomatic patients is associated with an extraordinarily high risk-factor for development of cancer.


Breast thermography is not new to medicine; its use has been advocated, and its medical efficacy challenged and debated, for years. The history of thermography has been characterized by both enthusiasm and pessimism regarding its efficacy. In the early 1970s, the US Department of Health, Education and Welfare concluded that thermography was beyond the experimental stage and was an accepted method for the evaluation of breast pathology. Excited by the availability of this new technology, and with little or no understanding of how to interpret the complicated photographs which were frequently of poor quality, the medical community began to rely on thermography as a 'stand-alone' diagnostic technique. Interpretive errors were frequent and often of a severe nature. Thermography again 'failed' to demonstrate effectiveness as a diagnostic modality in the BCDDP Project (1977) because of poor data acquisition and subjective interpretation in many of the BCDDP centres. The general use of this promising technique was again postponed because an objective method was not available to properly evaluate the thermograms. Subjective analytical methods had proven to be almost totally inadequate and resulted in interpretive inaccuracies and errors.


The previously recognized deficiencies of thermography for breast cancer detection and/or screening have been fully addressed and answered by the CBT Test. This highly disciplined and structured thermographic methodology differs significantly from past thermo-graphic procedures since, in the CBT Test protocol, thermograms are recorded in accordance with a strict examination protocol, and interpreted by an objective proprietary computerized method.


Recent advances in thermogram recording systems and related technologies have greatly improved the thermal pattern resolution and photographic quality of thermographic images; however, the most important recent development in breast thermography is the identification of the various thermobiological signs and the correlation of these signs to the pathology present in the breast. The task of successfully translating these thermal patterns into useful clinical information was performed by Dr Michel Gautherie at the University of Louis Pasteur School for Medicine, in Strasbourg, France. For over 18 years he examined and followed more than 150,000 symptomatic women, employing thermography, mammography, ultrasound, diaphanoscopy, physical examination and biopsy in his examinations. As a physicist and physiologist, Gautherie was in a superb position to successfully correlate the observed thermal characteristics with specific biophysical mechanisms and known pathological conditions. As a result, he successfully developed an objective interpretation method for breast thermography characterized by outstanding accuracy. The Gautherie interpretation method carefully evaluates thermograms to determine the presence of 20 different thermal characteristics and then compares those results with an extensive research data base. Each thermal characteristic is assigned a weighted score in conformance with the statistics of the data base. When the analysis is complete, the scores are evaluated, and the thermal classification is calculated.


COMPUTERIZED THERMOGRAPHY - OBJECTIVITY AND ACCURACY

Fundamental to the success of the CBT Test is the computer software used in its interpretation phase. The CBT software conforms exactly to the Gautherie Model and has been shown to be objective and reproducible, thereby providing a reliable and standard interpretation method. The only program of its type and capability, it has for the first time brought the consistency of computers to the interpretation of breast thermograms. The objectivity achieved in the computerized analysis of thermograms by the CBT Test is unsurpassed; uniform, repeatable and credible risk-factor assessments are produced time and time again, when the computer interpretation technique is used by trained operators.


Digital image processing is used in the CBT Test to extract otherwise occult thermal characteristics from the 'noise' of the photograph, enhancing the ability to gather as much meaningful information from the thermograms as is possible. The strength of the computer program, however, lies in its ability to force objective responses to questions designed to evaluate the thermal signs of the breast. Colour-graphic techniques are used throughout the program to provide operator aid and to clearly illustrate and delineate the thermographic signs essential to the objective analysis of the breast.


Dr. Gautherie is an expert in accurately evaluating breast thermograms; the CBT computer program was written to impart his capabilities to other, less experienced individuals who would eventually be responsible for objectively interpreting thermograms. To aid in satisfying this program criterion, especially strict design parameters were imparted to the computer software; it essentially mandated that the computer be a virtual duplication of Gautherie's technique. Paramedic personnel have become competent at replicating Gautherie's method after only minimal training using the Micro-Thermology Co. computer and software. Commenting on the efficacy of the computerized system, Gautherie stated in a recent paper[10]:


... Blind studies have shown that accuracy, objectivity and repro-ducibility of the interpretation are greatly improved using such a computer-assisted protocol. The possibility of misinterpretation by subjective feeling or impression on the part of the reader has proven to be markedly reduced.

The objectivity of the CBT interpretation system was also clearly evidenced in the same paper:


In order to assess the reliability of the results produced by the computer-assisted scoring system, a series of blind studies were carried out in our laboratory and in other breast centers ... A total of eleven analysts with different levels of experience ... participated in these studies ... Each analyst read two series of 500 thermograms, one ... recorded with a liquid crystal system, and the other with an infrared scanner, on symptomatic patients ... analysts who initially had no experience in thermographic interpretation ... were able to produce results similar to those obtained by the analysts who ... had practiced it for more than three years.

The introduction of the Micro-Thermology Co. computerized interpretation system now makes it possible to correctly interpret properly recorded thermographic information. The CBT Test provides the medical community with a previously unavailable technique for the reproducible interpretation of breast thermograms because the Test reduces the possibility of subjective interpretations which could result in significant interpretive errors.


EXAMINATION PROTOCOL - RIGID CRITERIA YIELD HIGH ACCURACY

The CBT Test software itself cannot obscure the errors inherent in improper testing procedures. A comprehensive and strict CBT examination protocol is necessary to maximize the efficacy of the Test by assuring reproducibility and by eliminating various factors which could alter the thermal characteristics of the breasts. The reliability and integrity of the Tests depends on conformance with the protocol; however, proper patient scheduling, simple preparation requirements, and careful attention to examination room conditions are all that is required to meet the criteria for an accurate CBT Test.


For brevity, the original protocol described in this paper has been omitted. The updated protocol is accessible via the menu, below.


CBT TEST RECORDING EQUIPMENT

To maximize the integrity of the Test, thermograms submitted for computer-assisted interpretation must be of high quality and should display clearly all of the information required in order to perform an objective analysis. Deficiencies in the recording process can render the Test useless.


The CBT Test can be performed using high-quality infra-red scanners which are available for CBT studies; however, these units are expensive, and generally not required in the primary-care environment. CBT Tests are typically recorded with cholesteric liquid crystal heat measurement devices that are placed in contact with the skin. The crystals change colour in response to variations in surface temperature, producing a multicoloured image representative of the temperature patterns on the surface of the breasts. A colour photograph of the thermal patterns provides a permanent recording for interpretation and future comparison studies. Modern liquid crystal thermogram recording systems are cost-effective, making them ideal for recording high-quality photographic images of CBT Test breast thermograms. Micro-Thermology's thermogram recording system uses cholesteric liquid crystals which are embedded in flexible sheets; when lightly pressed against the patient, these sheets easily contour to the shape of the breasts. The elastomeric sheets are wide enough to provide complete bilateral breast studies with excellent visualization of the axilla and sternum.


Illnesses, with or without temperature elevation, may alter the normal thermal characteristics of the breasts; thus, patients suffering from colds, influenza, etc. should not be scheduled for a BTE.


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