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Peripheral facial paralysis aided by infrared thermography.

Peripheral facial paralysis aided by infrared thermography.
We have carried out clinical observations on 34 patients with peripheral facial paralysis treated by
acupuncture therapy prescribed according to selection of treatment regimen on the basis of facial
thermogram and temperature. A comparison was made with a control group of 97 patients who received conventional acupuncture therapy only. It was found that: (1) The cure rate in the group of selecting acupoints by thermogram (hereinafter referred to as the thermography--aided treatment group) was 67.65%, with a marked improvement rate of 26.40%; while the cure rate of the conventional acupuncture treatment group (hereinafter called the conventional treatment group) was 46.39%, the marked improvement rate being 29.90%, indicating a significant difference in therapeutic efficacy between the two groups (P less than 0.02). (2) The average duration of acupuncture therapy for the thermography aided treatment group was 6.02 weeks, whereas that for the conventional treatment group, 24 weeks. There was also a significant difference between the two groups (p less than 0.01). (3) During the entire therapeutic course, 25.2 sessions of treatment were given on the average in the thermography--aided treatment group, and 78.8 sessions in the conventional treatment group, showing a very significant difference (P less than 0.001). The present thermography--aided method exhibits advantages over the conventional one in enhancing the cure rate and shortening the duration of treatment, which is worthy to be popularized in clinical practice. It is also of certain significance in standardization and scientification of acupuncture therapy.
Zhang D; Wei Z; Wen B; Gao H; Peng Y; Wang F.

Facial skin surface temperature changes during a "concealed information" test.

Facial skin surface temperature changes during a "concealed information" test.
Department of Defense Polygraph Institute, 7540 Pickens Ave., Fort Jackson, SC, 29207, USA.

When individuals who commit a crime are questioned, they often show involuntary physiological
responses to remembered details of that crime. This phenomenon is the basis for the concealed
information test, in which rarely occurring crime-related details are embedded in a series of more
frequently occurring crime-irrelevant items while respiratory, cardiovascular, and electrodermal responses are recorded. Two experiments were completed to investigate the feasibility of using facial skin surface temperature (SST) measures recorded using high definition thermographic images as the physiological measure during a concealed information test. ... During both experiments, there were significant facial SST differences between deceptive and nondeceptive participants early in the analysis interval. In the second experiment, hemifacial (i.e., "half-face" divided along the longitudinal axis) effects were combined with the bilateral responses to correctly classify 91.7% of participants. These results suggest that thermal image analysis can be effective in discriminating deceptive and nondeceptive individuals during a concealed information test.

Infrared thermography as an access pathway for individuals with severe motor impairments.

Infrared thermography as an access pathway for individuals with severe motor impairments.
Memarian N, Venetsanopoulos AN, Chau T. Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Canada.

BACKGROUND: People with severe motor impairments often require an alternative access pathway, such as a binary switch, to communicate and to interact with their environment. A wide range of access pathways have been developed from simple mechanical switches to sophisticated physiological ones. In this manuscript we report the inaugural investigation of infrared thermography as a non-invasive and non-contact access pathway by which individuals with disabilities can interact and perhaps eventually communicate.

METHODS: Our method exploits the local temperature changes associated with mouth opening/closing to enable a highly sensitive and specific binary switch. Ten participants (two with severe disabilities) provided examples of mouth opening and closing. Thermographic videos of each participant were recorded with an infrared thermal camera and processed using a computerized algorithm. The algorithm detected a mouth open-close pattern using a combination of adaptive thermal intensity filtering, motion tracking and morphological analysis.

RESULTS: High detection sensitivity and low error rate were achieved for the majority of the participants (mean sensitivity of all participants: 88.5% +/- 11.3; mean specificity of all participants: 99.4% +/- 0.7). The algorithm performance was robust against participant motion and changes in the background scene.

CONCLUSION: Our findings suggest that further research on the infrared thermographic access pathway is warranted. Flexible camera location, convenience of use and robustness to ambient lighting levels, changes in background scene and extraneous body movements make this a potential new access modality that can be used night or day in unconstrained environments.

Peripheral facial paralysis aided by infrared thermography.

Journal of Traditional Chinese Medicine, 1991 Jun, 11(2):139-45
Peripheral facial paralysis aided by infrared thermography.

We have carried out clinical observations on 34 patients with peripheral facial paralysis treated by
acupuncture therapy prescribed according to selection of treatment regimen on the basis of facial
thermogram and temperature. A comparison was made with a control group of 97 patients who received conventional acupuncture therapy only. It was found that: (1) The cure rate in the group of selecting acupoints by thermogram (hereinafter referred to as the thermography--aided treatment group) was 67.65%, with a marked improvement rate of 26.40%; while the cure rate of the conventional acupuncture treatment group (hereinafter called the conventional treatment group) was 46.39%, the marked improvement rate being 29.90%, indicating a significant difference in therapeutic efficacy between the two groups (P less than 0.02). (2) The average duration of acupuncture therapy for the thermography aided treatment group was 6.02 weeks, whereas that for the conventional treatment group, 24 weeks. There was also a significant difference between the two groups (p less than 0.01). (3) During the entire therapeutic course, 25.2 sessions of treatment were given on the average in the thermography--aided treatment group, and 78.8 sessions in the conventional treatment group, showing a very significant difference (P less than 0.001). The present thermography--aided method exhibits advantages over the conventional one in enhancing the cure rate and shortening the duration of treatment, which is worthy to be popularized in clinical practice. It is also of certain significance in standardization and scientification of acupuncture therapy.
Zhang D; Wei Z; Wen B; Gao H; Peng Y; Wang F.

Thermography and colour duplex ultrasound assessments of arterio-venous fistula function in renal patients.

Thermography and colour duplex ultrasound assessments of arterio-venous fistula function in renal patients. 

Allen J, Oates CP, Chishti AD, Ahmed IA, Talbot D, Murray A. Source Regional Medical Physics Department, Freeman Hospital, Newcastle upon Tyne NE7 7DN, UK. john.allen@nuth.nhs.uk

Abstract 

Vascular and clinical assessments of arterio-venous fistula (AVF) function and access are important in patients undergoing or preparing to undergo renal dialysis. Objective assessment techniques include colour duplex ultrasound and more recently medical infrared thermography. Ideally, these should help assess problems relating to fistula failure or to vascular steal from the hand which can result from excessive fistula blood flow. The clinical value of thermography, as yet, has not been assessed for this patient group. The aims of this study were therefore to investigate the relationships between thermography skin temperature measurement and (a) quantitative ultrasound measurement of AVF blood flow, and (b) qualitative clinical assessment of vascular steal from the hands. Fifteen adult patients underwent thermal imaging of the upper limbs, colour duplex ultrasound to derive AVF blood flow from brachial artery blood flow measurements, and a clinical evaluation for vascular steal. Temperature measurements were extracted from the thermograms, including bilateral arm and hand (Fistula -- Non-Fistula) differences, for comparison with derived AVF blood flow and steal grading. Derived AVF blood flow ranged from 30 to 1,950 ml min(-1), with a mean rate close to one litre per minute. Thermography detected the warmer superficial veins in proximity to the patent fistulas, with bilateral differences in fistula region skin temperature correlated with derived AVF blood flow (using maximum temperature measurements the correlation was +0.71 [p < 0.01]; and using mean temperature measurements the correlation was +0.56 [p < 0.05]). When thermography measurements were compared with the clinical assessment of steal the mean hand temperature differences separated steal from non-steal patients with an accuracy of greater than 90%. In summary, we have now demonstrated the potential clinical value of medical infrared thermography for assessing AVF function in renal patients.

Thermography and laser-Doppler flowmetry for monitoring changes in finger skin blood flow upon cigarette smoking.

Clin Physiol 1991 Mar;11(2):135-41
Thermography and laser-Doppler flowmetry for monitoring changes in finger skin blood flow upon cigarette smoking.
Bornmyr S, Svensson H.; Department of Clinical Physiology, Allmanna Sjukhuset, Malmo, Sweden.

Haemodynamic changes after smoking two 1.1 mg nicotine cigarettes were monitored in 24 smokers on two different occasions. Smoking caused an increase in heart rate and arterial blood pressure, whereas finger temperature as measured by thermography and finger skin blood flow as measured by laser-Doppler flowmetry (LDF) decreased. Lowest values were seen within 15 min by LDF, and after 30 min by thermography. Changes in the two methods correlated closely, however, when maximum responses during a 45-min period after smoking were compared. The wider distribution of LDF values would seem to be due to the small measuring volume which is susceptible to differences in vascular anatomy and reactivity. In both methods, responses showed a high degree of reproducibility.

Beating Breast Cancer
William Hobbins, MD, FABS, DABCT, FIACT William Amalu, DC, DABCT, DIACT,
FIACT

This year, over 192,000 women will be diagnosed with breast cancer in the US and 1.2 million worldwide (Source: American Cancer Society and WHO). As shocking as these numbers are, even worse is the number of cancers that won’t be detected until it’s too late. The consensus among
experts is that early detection holds the key to survival. Although this is true, detection is not occurring early enough. Even though women are advised to begin having mammograms at 40, what they don’t know is that by the time most cancers are detected they have been growing for 10 years, and that 20% of all cancers can’t be seen by a mammogram. It is because of these factors, and others, that the number of women who die from this disease has gone relatively unchanged in the past 40 years.

A change from sole dependence upon procedures that only provide detection of existing cancers to technologies that reflect the early cancerous process itself would provide women with true screening.




If a significant change in breast cancer mortality is to be realized, we have to rethink what screening tests truly are. Are we currently providing “screening” or “detection”? A critical look at what we are
providing women must be made.  If there were a method of very early detection, a procedure that would act as an early warning system, women would have the fighting chance they need to win this battle. What is needed is a biological risk marker. A biological risk marker would be able to turn these grave statistics around, as aggressive tissues would be detected before they were able to
invade the rest of the body. Women now have access to a unique technology that can give them this early warning; a procedure called Breast Thermography.

Breast thermography is an imaging technology that uses advanced computerized infrared camera systems to detect heat patterns in the breast. When a cancer is forming it develops its own blood supply in order to feed its accelerated growth (a process known as malignant angiogenesis). Even
more important, precancerous tissues can start this process well in advance of the cells becoming malignant. This increased Research has determined that the single greatest risk factor for the future development of breast cancer is lifetime exposure of the breasts to estrogen. In which case,  controlling the influence of estrogen on the breasts would be the single greatest method of primary breast cancer prevention. Studies show that breast thermography has the ability to warn a woman that a cancer may be forming up to 10 years before any other test can detect it. blood supply causes an abnormal heat pattern in the breast. Thermography can detect this abnormal heat pattern by scanning the breasts with a specialized infrared camera and analyzing the information using sophisticated computer programs under the guidance of a doctor who is board certified in the procedure. These abnormal heat patterns are among the earliest known signs of a forming cancer.

Studies show that this technology has the ability to warn a woman that a cancer may be forming up to 10 years before any other test can detect it.

An unprecedented level of early detection can be realized when thermography is added to a
woman’s regular breast health care. It has been found that an abnormal thermographic image is the single most important sign of high risk for developing breast cancer, 10 times more significant than a first order family history of the disease.  This gives breast thermography not only the ability to detect cancer at its earliest and most treatable stage, but to also act as a biological marker warning a woman about her own unique level of future risk for breast cancer.

Women who undergo the test find it to be fairly uneventful, since the procedure uses no radiation or contact with the breasts. Women with dense breasts, implants, and women who are pregnant or nursing can be imaged without any harm or reduction in the accuracy of the test. Normal images, show evenly cool inactive breasts (dark colors represent cold areas). Abnormal images, as seen on the right, show highly active blood vessels giving off heat in one breast. Since the procedure does not pose any harm to the patient, women who are at higher risk can be monitored closely without adverse effects on their health.

Research has determined that the single greatest risk factor for the future development of breast cancer is lifetime exposure of the breasts to estrogen. In which case, controlling the influence of estrogen on the breasts would be the single greatest method of primary breast cancer prevention.

Another benefit of this technology is its role in primary breast cancer prevention. Breast  thermography has the added ability to observe the influence of hormones on the breasts.  When hormone activity in the breast is dominated by estrogen, a specific type of infrared image is produced; thus, warning the patient of this condition. Once this is identified, a woman can take a significant pro-active role in prevention. With this information in hand, many doctors start their patients on a regimen of progesterone cream applied directly to the breasts. The progesterone enters
the breast tissue and counteracts the effects of estrogen. Using follow up infrared imaging, the treatment can be monitored and changed if necessary to meet the needs of each woman’s own unique physiology. Once the hormone balance has been restored to the breasts, a woman’s overall breast cancer risk is greatly reduced. The lifesaving implication of having this knowledge is incredible.

With the incidence of breast cancer steadily rising in women under 40, an effort to provide some form of accurate screening test is needed in this age group. Very early detection is especially important since breast cancers in younger women are commonly more aggressive resulting in lower survival rates. Current screening procedures have proven to be inaccurate in women in this age group due to breast tissue density and other factors. These issues, however, do not affect thermography. With this technology, women under 40 now have a safe and objective screening method that they can add to their regular breast health checkups.

Breast thermography is a high-tech non-invasive screening procedure designed to be used by women of all ages. The technology has been thoroughly researched for over 30 years and is FDA approved for use in breast cancer screening. Its unique ability to play a significant role in prevention is an impressive added benefit. Unfortunately, at this time there are too few qualified clinical thermography centers worldwide. However, with the increasing demand for breast thermography, recognized educational organizations, such as the International Academy of Clinical Thermology, are actively seeking personnel for training as certified technicians. It is their goal to provide women with greater access to this lifesaving technology.

Currently, no single screening procedure can detect 100% of all breast cancers. Thermography is designed to be used with mammography and not as a replacement. Studies show that when thermography is added to a woman’s regular breast health checkups (physical examination + mammography + thermography), 95% of all early stage cancers will be detected. This would give the vast majority of women who are diagnosed with this disease the reality of returning to a normal healthy life.

Should we continue to concentrate our efforts on procedures that can only detect an existing cancer, or should we be focusing on true screening methods that can warn of a pending problem far in advance? The number of women who die from this disease will continue relatively unchanged if nothing is done to provide them with a true early warning system. Breast thermography has the unique ability to warn most women far enough in advance to give them a fighting chance. Combined
with its ability to play a role in primary prevention, the lifesaving implications are incredible. The addition of this technology to every woman’s breast health care will make the greatest impact
on breast cancer mortality. With breast thermography, women of all ages are given hope and a true early detection edge in the battle against breast cancer.

About the authors-

William Hobbins, MD, a Fellow of the American Board of Surgeons and a board certified clinical thermologist, has been performing thermographic breast imaging for over 35 years. As an internationally recognized authority in this field, he has sat on multiple medical and thermographic boards, authored numerous articles, and has contributed a significant amount of research to the medical database using this technology. He currently practices in Madison Wisconsin and can be contacted at 608-273-4274.

William Amalu, DC, a Fellow of the International Academy of Clinical Thermology and a board certified clinical thermologist, has utilized thermography in practice for over 14 years. He is currently the President of the International Academy of Clinical Thermology and practices in Redwood City California. He can be contacted at 650-361-8908
www.breastthermography.com
http://www.stocktonfp.com/Articles/Beating%20Breast%20Cancer.pdf

Quantitative assessment of tumor vasculature and response to therapy in kaposi's sarcoma using functional noninvasive imaging.

Quantitative assessment of tumor vasculature and response to therapy in kaposi's sarcoma using functional noninvasive imaging.

Hassan M, Little RF, Vogel A, Aleman K, Wyvill K, Yarchoan R, Gandjbakhche AH. Source Laboratory of Integrative and Medical Biophysics, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA. hassanm@mail.nih.gov

Abstract
Two noninvasive methods, thermography and laser Doppler imaging (LDI), were assessed for their ability to quantitatively assess parameters of vascularity in lesions of HIV-associated Kaposi's sarcoma (KS). Thermography and LDI images of a representative KS lesion were recorded in 16 patients and compared to normal skin either adjacent to the lesion or on the contralateral side. Eleven of the 16 patients had greater than 0.5 degrees C increased temperature and 12 of the 16 patients had increased flux (measured by LDI) as compared to normal skin. There was a strong correlation between these two parameters (R = 0.81, p < 0.001). In ten patients, measurements were obtained prior to therapy and after receiving a regimen of liposomal doxorubicin and interleukin-12. After 18 weeks of therapy, temperature and blood flow of the lesions were significantly reduced from the baseline (p = 0.004 and 0.002 respectively). These techniques hold promise to assess physiologic parameters in KS lesions and their changes with therapy.

PMID: 15453810 [PubMed - indexed for MEDLINE

Application of thermography in dentistry--visualization of temperature distribution on oral tissues.

Application of thermography in dentistry--visualization of temperature distribution on oral tissues.

Komoriyama M, Nomoto R, Tanaka R, Hosoya N, Gomi K, Iino F, Yashima A, Takayama Y, Tsuruta M,

Tokiwa H, Kawasaki K, Arai T, Hosoi T, Hirashita A, Hirano S.; Department of Dental Engineering,

Tsurumi University School of Dental Medicine, 2-1-3 Tsurumi, Tsurumi-ku, Yokohama 230-8501, Japan.

The purpose of this study was to devise and propose appropriate conditions for the photographing of

thermal images in the oral cavity and to evaluate which thermography techniques can be applied to

dentistry by evaluating the differences in temperature among oral tissues. Thermal images of oral cavities

of 20 volunteers in normal oral condition were taken according to the guidelines of the Japanese Society

of Thermography, with five added items for oral observation. The use of a mirror made it possible to take

thermal images of the posterior portion or palate. Teeth, free gingiva, attached gingiva and alveolar

mucosa were identified on thermal images. There were differences in temperature between teeth, free

gingiva, attached gingiva and alveolar mucosa. These were nearly in agreement with the anatomical

view. Thermography need no longer be restricted to the anterior portion using a mirror, and can

now be applied to the dental region.

New breast cancer screening guidelines released

New breast cancer screening guidelines released

Canadian Task Force on Preventive Health Care issues updated guidelines

New breast cancer screening guidelines for women at average risk of breast cancer, published in CMAJ(Canadian Medical Association Journal), recommend no routine mammography screening for women aged 40–49 and extend the screening interval from every 2 years, which is current
clinical practice, to every 2 to 3 years for women aged 50–74. The guidelines also recommend against routine clinical breast exam and breast self-examination in asymptomatic women.

The guidelines, aimed at physicians and policy-makers, provide recommendations for mammography, magnetic resonance imaging (MRI), breast self-exams and clinical breast exams by clinicians. They target average-risk women in three age groups (40–49, 50–69 and 70–74 years) who have not had breast cancer and do not have a family history of breast cancer in a mother, sister or daughter.

“As the Guideline on Breast Cancer Screening was last updated in 2001 and breast cancer screening has since become a subject for discussion amongst doctors and patients, the revitalized Canadian Task Force selected breast cancer screening as the topic for its first guideline,” said Dr. Marcello Tonelli, Chair of the Task Force on Preventive Health Care and Associate Professor at the University of Alberta, Department of Medicine, in Edmonton, Alberta. "We intend that this Guideline, which
reflects the latest scientific evidence in breast cancer screening, be used to guide physicians and their patients regarding the optimum use of mammograms and breast examination.”

According to the guideline, outcomes of breast cancer screening such as tumor detection and mortality must be put into context of the harms and costs of false–positive tests, over-diagnosis and over-treatment. False–positive results can have a significant impact on the emotional well-being of patients and families. They can cause lifestyle disruptions and result in costs to both patients and the health care system.

“Providing Canadians with guidelines that reflect the most current scientific evidence is our priority," said Dr. Tonelli. “We encourage every woman to discuss the risks and benefits of screening with their doctor before deciding on the best approach for them.”

Key recommendations:

No routine mammography for women aged 40-49 because the risk of cancer is low in this group   while the risk of false–positive results and over-diagnosis and over-treatment is higher
Routine screening with mammography every two to three years for women aged 50-69
Routine screening with mammography every two to three years for women aged 70-74
No screening of average-risk women using MRI
No routine clinical breast exams or breast self-exam to screen for breast cancer.

“There was no evidence that screening with mammography reduces the risk of all-cause mortality,” state the authors. “Although screening might permit surgery for breast cancer at an earlier stage than diagnosis of clinically evident cancer (thus permitting the use of less invasive procedures for some women), available trial data suggest that the overall risk of mastectomy is significantly increased among recipients of screening compared with women who have not undergone screening.”

In addition to the full guidelines, one-page information pieces are available for both physicians and patients on the task force website: www.canadiantaskforce.ca

The Canadian Task Force on Preventive Health Care is an independent body of 14 primary care and prevention experts. The task force has been established by the Public Health Agency of Canada to develop clinical practice guidelines that support primary care providers in delivering preventive health care.

In a related commentary, Dr. Peter Gøtzsche, Nordic Cochrane Centre, Copenhagen, Denmark, writes, “these guidelines are more balanced and more in accordance with the evidence than any previous recommendations.”

He states that evidence does not support mammography screening and argues that screening is ineffective and even harmful because diagnosis of cancers that would otherwise be undetected lead to life-shortening treatments and mastectomies.

“The main effect of screening is to produce patients with breast cancer from among healthy women who would have remained free of breast disease for the rest of their lives had they not undergone screening,” writes Dr. Gøtzsche.

“The best method we have to reduce the risk of breast cancer is to stop the screening program,” he concludes. “This could reduce the risk by one-third in the screened age group, as the level of overdiagnosis in countries with organized screening programs is about 50%.”

MEDIA NOTE: Please use the following public links after the embargo lift:
Research http://www.cmaj.ca/lookup/doi/10.1503/cmaj.110334
Commentary http://www.cmaj.ca/lookup/doi/10.1503/cmaj.111721
Media contact for guidelines:
David Rodier
Hill & Knowlton
(613) 786 9945
david.rodier@hillandknowlton.ca

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Can rotational atherectomy cause thermal tissue damage? A study of the potential heating and thermal tissue effects of a rotational atherectomy device

Cardiovasc Intervent Radiol 1998 Nov-Dec;21(6):481-6

Can rotational atherectomy cause thermal tissue damage? A study of the potential heating and thermal tissue effects of a rotational atherectomy device.

Gehani AA, Rees MR; Cardiac Research Unit, Killingbeck Hospital, Leeds, United Kingdom.

PURPOSE: Thermal tissue damage (TTD) is customarily associated with some lasers. The thermal potential of rotational atherectomy (RA) devices is unknown. We investigated the temperature profile and potential TTD as well as the value of fluid flushing of an RA device.

METHODS: We used a high-resolution infrared imaging system that can detect changes as small as 0.1 degree C to measure the temperature changes at the tip of a fast RA device with and without fluid flushing. To assess TTD, segments of porcine aorta were subjected to the rotating tip under controlled conditions, stained by a special histochemical stain (picrisirius red) and examined under normal and polarized light microscopy.

RESULTS: There was significant heating of the rotating cam. The mean "peak" temperature rise was 52.8 +/- 16.9 degrees C. This was related to rotational speed; thus the "peak" temperature rise was 88.3 +/- 12.6 degrees C at 80,000 rpm and 17.3 +/- 3.8 degrees C at 20,000 rpm (p < 0.001, t-test). Fluid flushing at 18 ml/min reduced, but did not abolish, heating of the device (11.8 +/- 2.9 degrees C). A crater was observed in all segments exposed to the rotating tip. The following features were most notable: (i) A zone of "thermal" tissue damage extended radially from the crater reaching adventitia in some sections, especially at high speeds. This zone showed markedly reduced or absent birefringence. (ii) Fluid flushing of the catheter reduced the above changes but increased the incidence and extent of dissections in the media, especially when combined with high atherectomy speeds. (iii) These changes were observed in five of six specimens exposed to RA without flushing, but in only one of six with flushing (p < 0.05). (iv) None of the above changes was seen in control segments.

CONCLUSION: RA is capable of generating significant heat and potential TTD. Fluid flushing reduced heating and TTD. These findings warrant further studies in vivo, and may influence the design of atherectomy devices.

Possibility of the thermographic method for detection of ischemic myocardium

Possibility of the thermographic method for detection of ischemic myocardium.

Liakas R¹, Krishchiukaĭtis A, Iakushka P, Tsivinskene G, Veĭkutis V, Antushevas A, Vaĭchiulite R.

Author information

Abstract

Thermography (TG) is used as a contact free method for investigation of the myocardium ischemic injury. In coronary bypass surgery without artificial blood circulation it is important to know how cessation of blood supply affects the myocardium. In experiments on working heart, TG allows monitoring temperature at the desired point of the epicardium. The aim was to investigate relations between myocardial ischemia and temperature and to prove that the ischemic tissue and border zones can be determined by TG. Experiments were performed on mongrel dogs. In the areas of induced ischemia, ventricular surface thermograms (T) and electrograms (EG) were recorded. The obtained data showed that temperatures in ischemic area and border zone of myocardium were different from those in healthy myocardium. A detailed analysis of T of ischemic area showed that between ischemic and healthy myocardium a border zone is formed which is very important for arrhythmia genesis. The border zone is several millimeters wide, and its temperature is 1C higher than in healthy myocardium. The curve of the dynamics of temperature measured at all points of the ischemic zone has been created. Correlation between myocardium temperatures and characteristics of EG of ischemic zones is shown. 

Conclusion- The data show that TG is an appropriate method for determination of ischemic area and border zone in ventricular myocardium. TG gives a possibility to evaluate functional status of myocardium in a contact free way and may be applied for determination of ischemic damage of myocardium during cardiosurgery.