Herman C, Pirtini Cetingul M. Department of Mechanical Engineering, The Johns Hopkins University.

J Vis Exp. 2011 May 5;(51).

In 2010 approximately 68,720 melanomas will be diagnosed in the US alone, with around 8,650 resulting in death (1). To date, the only effective treatment for melanoma remains surgical excision, therefore, the key to extended survival is early detection (2,3). Considering the large numbers of patients diagnosed every year and the limitations in accessing specialized care quickly, the development of objective in vivo diagnostic instruments to aid the diagnosis is essential. New techniques to detect skin cancer, especially non-invasive diagnostic tools, are being explored in numerous laboratories. Along with the surgical methods, techniques such as digital photography, dermoscopy, multispectral imaging systems (MelaFind), laser-based systems (confocal scanning laser microscopy, laser doppler perfusion imaging, optical coherence tomography), ultrasound, magnetic resonance imaging, are being tested. Each technique offers unique advantages and disadvantages, many of which pose a compromise between effectiveness and accuracy versus ease of use and cost considerations. Details about these techniques and comparisons are available in the literature (4). Infrared (IR) imaging was shown to be a useful method to diagnose the signs of certain diseases by measuring the local skin temperature. There is a large body of evidence showing that disease or deviation from normal functioning are accompanied by changes of the temperature of the body, which again affect the temperature of the skin (5,6). Accurate data about the temperature of the human body and skin can provide a wealth of information on the processes responsible for heat generation and thermoregulation, in particular the deviation from normal conditions, often caused by disease. However, IR imaging has not been widely recognized in medicine due to the premature use of the technology (7,8) several decades ago, when temperature measurement accuracy and the spatial resolution were inadequate and sophisticated image processing tools were unavailable. This situation changed dramatically in the late 1990s-2000s. Advances in IR instrumentation, implementation of digital image processing algorithms and dynamic IR imaging, which enables scientists to analyze not only the spatial, but also the temporal thermal behavior of the skin (9), allowed breakthroughs in the field. In our research, we explore the feasibility of IR imaging, combined with theoretical and experimental studies, as a cost effective, non-invasive, in vivo optical measurement technique for tumor detection, with emphasis on the screening and early detection of melanoma (10-13). In this study, we show data obtained in a patient study in which patients that possess a pigmented lesion with a clinical indication for biopsy are selected for imaging. We compared the difference in thermal responses between healthy and malignant tissue and compared our data with biopsy results. We concluded that the increased metabolic activity of the melanoma lesion can be detected by dynamic infrared imaging.

Chubb D, Rozen WM, Whitaker IS, Ashton MW.

The Taylor Laboratory, Jack Brockhoff Reconstructive Plastic Surgery Research Unit, Department of Anatomy and Cell Biology, The University of Melbourne, Parkville, Victoria 3050, Australia.

Ann Plast Surg. 2011 Apr;66(4):324-5. WM, Whitaker IS, Ashton MW.

The Taylor Laboratory, Jack Brockhoff Reconstructive Plastic Surgery Research Unit, Department of Anatomy and Cell Biology, The University of Melbourne, Parkville, Victoria 3050, Australia.

Ann Plast Surg. 2011 Apr;66(4):324-5.

Preoperative imaging to identify the location of individual perforators has been shown to improve operative outcomes, and while computed tomographic angiography (CTA) and magnetic resonance angiography are currently the most widely used modalities, these have substantial limitations. Such limitations include the need for intravenous access, the need for iodinated contrast media, radiation exposure with CTA, and long scanning times with magnetic resonance angiography. Complications from the use of contrast media are also noteworthy, and can include anaphylactoid reactions and renal toxicity. In a move to avoid these problems, we have recently introduced a technique that is readily available and easy to implement for preoperative imaging, and may show an accuracy that matches the more advanced imaging modalities. Thermal imaging is a readily performed technique, and can be undertaken by the reconstructive surgeon themselves at the initial consultation, enabling prompt operative planning, and avoiding the need for delays in imaging, confusion in the interpretation of a radiologist report, and the need for an intermediary radiologist altogether. In our experience thus far, the technique matches the accuracy for location of CTA, and a larger clinical trial of the technique is underway.

Gralewicz G, Wiecek B.

Department of Personal Protective Equipment, Central Institute for Labour Protection – National Research Institute, Łódź, Poland.

Int J Occup Saf Ergon. 2009;15(4):363-71.

This is a study of the possibilities of a qualitative evaluation of protective materials with active thermography. It presents a simulation of a periodic excitation of a multilayer composite material. Tests were conducted with lock-in thermography on Kevlar composite consisting of 16 layers of Kevlar fabric reinforced with formaldehyde resin with implanted delamination defects. Lock-in thermography is a versatile tool for nondestructive evaluation. It is a fast, remote and nondestructive procedure. Hence, it was used to detect delaminations in the composite structure of materials used in the production of components designed for personal protection. This method directly contributes to an improvement in safety.

Clark AT, Mangat JS, Tay SS, King Y, Monk CJ, White PA, Ewan PW.

Department of Allergy, Cambridge University Hospitals NHS Trust, Addenbrookes Hospital, Cambridge, UK.

Allergy. 2007 Jul;62(7):744-9

BACKGROUND: Oral challenge is widely used for diagnosing food allergy but variable interpretation of subjective symptoms may cause error. Facial thermography was evaluated as a novel, objective and sensitive indicator of challenge outcome. METHODS: A total of 24 children with a history of egg allergy underwent oral challenge, which were scored positive when objective symptoms occurred or negative after all doses were consumed without reaction. Facial temperatures were recorded at baseline and 10-min intervals. The difference between mean and baseline temperature (DeltaT), maximum DeltaT during challenge (DeltaT(max)) and area under curve of DeltaT against time (DeltaTAUC) were calculated for predefined nasal, oral and forehead areas, and related to objective challenge outcome. RESULTS: There were 13 positive and 11 negative challenges. Median nasal DeltaTAUC and DeltaT(max) were greater in positive compared with negative challenges (231- and 5-fold, respectively; P < 0.05). In positive challenges, nasal temperatures showed an early transient rise at 20 min, preceding objective symptoms at median 67 min. There was a sustained temperature increase from 60 min, which was reduced by antihistamines. A cut-off for nasal DeltaT(max) of 0.8 degrees C occurring within 20 min of the start of the challenge predicted outcome with 91% sensitivity (positive predictive value [PPV] 100%) and 100% specificity (negative predictive value [NPV] 93%). Subjective symptoms occurred in four of 13 positive and three of 11 negative challenges. CONCLUSIONS: Facial thermography consistently detects a significant early rise in nasal temperature during positive compared with negative food challenges, which is evident before objective symptoms occur. Thermography may therefore provide a sensitive method to determine outcome of food challenges and investigate the pathophysiology of food allergic reactions.

Al-Nakhli HH, Petrofsky JS, Laymon MS, Arai D, Holland K, Berk LS.1 Loma Linda University , Loma Linda, California.

Diabetes Technol Ther. 2011 Oct 19.

Exercise is of great value for individuals with diabetes in helping to control their hemoglobin A1c levels and in increasing their insulin sensitivity. Delayed-onset muscle soreness (DOMS) is a common problem in healthy individuals and in people who have diabetes. … Conclusion: Infrared thermal imaging may be a valuable technique of seeing which muscles are sore hours or even days after the exercise is over. Thus, thermal imaging would be an efficient and painless way of looking at DOMS in both healthy individuals and individuals who have diabetes, even if they are facing neurological problems.

Saxena AK, Willital GH.

Department of Pediatric Surgery, Medical University of Graz, Auenbruggerplatz 34, Graz, A-8036, Austria

Eur J Pediatr. 2007 Aug 30;

The aim of this study was to evaluate the feasibility of clinical application of infrared thermography (IRT) in the pediatric population and to identify pathological states that can be diagnosed as well as followed up using this non-invasive technique. In real time computer-assisted IRT, 483 examinations were performed over a period of 10 years from 1990-2000 on 285 patients in the pediatric age group (range 1 week-16 years) presenting with a wide range of pathologies. The temperature was measured in centigrade ( degrees C), and color images obtained were computer analyzed and stored on floppy discs. IRT was found to be an excellent noninvasive tool in the follow-up of hemangiomas, vascular malformations and digit amputations related to reimplantation, burns as well as skin and vascular growth after biomaterial implants in newborns with gastroschisis and giant omphaloceles. In the emergency room, it was a valuable tool for rapid diagnosis of extremity thrombosis, varicoceles, inflammation, abscesses, gangrene and wound infections. In conclusion, IRT can be performed in the pediatric age group, is non-invasive, without any biological side effects, requires no sedation or anesthesia and can be repeated as desired for follow-ups, with objective results that can demonstrated as colored images. Periodic thermographic studies to follow progression of lesions seem to be a useful and reproducible method.

Rose AD, Kanade V.

Eye Care Group, Yale University School of Medicine, Yale University School of Nursing, New Haven, Connecticut 06510-2716, USA.

PURPOSE: To assess intraoperative thermal levels at the wound site during divide-and-conquer phacoemulsification with the Sovereign with WhiteStar (SWS) system or the Legacy with AdvanTec and NeoSoniX (LAD) system. DESIGN: Prospective, randomized, parallel-group, comparative study. METHODS: Twenty-six subjects from a private clinical practice underwent divide-and-conquer phacoemulsification with either the SWS system or the LAD system. CB/CF settings (60%/33% duty cycles) were utilized with SWS and 12 pulses per second with the LAD system. Key criteria assessed were peak wound-site temperature, mean temperature change at the wound site, effective phaco time, average phaco power, procedure time, amount of BSS used, and surgical complications. RESULTS: Mean temperature change at the wound site was greater for the LAD than the SWS group. There was a statistically significant difference (P=.0002) in mean peak wound temperatures, with the LAD group having higher mean peak temperatures (42.47+/-5.33 degrees C) than the SWS group (36.59+/-1.33 degrees C). Highest wound-site temperature was 51 degrees C for the LAD group and 39.3 degrees C for the SWS group. A statistically significant difference (P=.0031) in mean peak temperature was found between the LAD and SWS systems for subjects with a cataract density of 4: higher mean peak temperatures were observed for LAD patients with a cataract density of 4. CONCLUSIONS: Our findings show that phacoemulsification using the SWS system results in lower peak temperatures and less temperature change at the phaco wound site compared with the LAD system.

Corvi A, Innocenti B, Mencucci R. Dipartimento di Meccanica e Tecnologie Industriali-Universita degli Studi di Firenze, via di S. Marta 3, 50139 Firenze, Italy.

Physiol. Meas. 2006 Apr;27(4):371-84. Epub 2006 Mar 8.

Thermography has been employed to analyze and compare three cataract surgery procedures performed in vivo with phacoemulsification, namely, the Sovereign phacoemulsification system with a traditional technique, the Sovereign WhiteStar phacoemulsification system with a traditional technique and the Sovereign WhiteStar phacoemulsification system with a bimanual technique. During the entire surgical procedure, the temperature of the ocular surface was monitored. The temperature values in the area where the phaco probe was inserted in the eye were measured, and the quantities of heat transmitted to the eye in the different procedures were assessed through suitable indices. In this study the highest temperature measured for each procedure during the surgical operation was 44.9 degrees C for the Sovereign phacoemulsification system with a traditional technique, 41 degrees C for the Sovereign WhiteStar phacoemulsification system with a traditional technique and 39.5 degrees C for the Sovereign WhiteStar phacoemulsification system with a bimanual technique, which is also the surgical procedure having the lowest thermal impact on the eye, i.e., the one in which the temperature peaks are lowest in amplitude and the least amount of heat is transmitted to the eye. Thermography, used in this study as a temperature monitoring instrument, has allowed analysis to be effected through a useful and advantageous methodology, totally non-invasive as regards both surgeon and patient, and has been applied in vivo without requiring any change in the surgical procedure.

Galvin EM, Niehof S, Medina HJ, Zijlstra FJ, van Bommel J, Klein J, Verbrugge SJ.

Department of Anesthesiology, Erasmus University Medical Center, Rotterdam, The Netherlands.

Anesth. Analg. 2006 Feb;102(2):598-604.

We designed this study to evaluate the usefulness of thermographic temperature measurement with an infrared camera, compared with patient response to cold and pinprick, as a means of assessing the success or failure of axillary blockades. Axillary blocks were performed on 25 patients undergoing surgery on the hand or forearm using a nerve stimulator technique with mepivacaine 1.5%. Pinprick and cold sensation were assessed on the operative site at 5-min intervals for 30 min. A thermographic image of the operative limb was recorded at similar time intervals. Thermographic images of the unblocked limb were taken before block placement and at 30 min. Temperature values at the operative site and unblocked limb were calculated from the thermographic images. Results revealed that thermography had higher combined values for sensitivity, specificity, and positive and negative predictive values than both cold and pinprick at all time intervals, with statistically significant differences at 15 min (thermography versus cold, P = 0.006; thermography versus pinprick, P = 0.026) and 30 min (thermography versus cold, P = 0.038; thermography versus pinprick, P = 0.040). For thermography as a method of block assessment, an optimal time of 15 min after mepivacaine local anesthetic injection gives the highest combined values for predicting a successful block (P = 0.004). We conclude that thermography provides an early and objective assessment of the success and failure of axillary regional blockades.

Gold JE, Cherniack M, Buchholz B. Department of Work Environment, University of Massachusetts Lowell, 1 University Avenue, MA 01854, Lowell, USA, Judith_Gold@uml.edu.

Eur J Appl Physiol. 2004 Oct;93(1-2):245-51.

Reduced blood flow may contribute to the pathophysiology of upper extremity musculoskeletal disorders (UEMSD), such as tendinitis and carpal tunnel syndrome. The study objective was to characterize potential differences in cutaneous temperature, among three groups of office workers assessed by dynamic thermography following a 9-min typing challenge: those with UEMSD, with ( n=6) or without ( n=10) cold hands exacerbated by keyboard use, and control subjects ( n=12). Temperature images of the metacarpal region of the dorsal hand were obtained 1 min before typing, and during three 2-min sample periods [0-2 min (early), 3-5 min (middle), and 8-10 min (late)] after typing. Mean temperature increased from baseline levels immediately after typing by a similar magnitude, 0.7 (0.3) degrees C in controls and 0.6 (0.2) degrees C in UEMSD cases without cold hands, but only by 0.1 (0.3) degrees C in those with cold hands. Using paired t-tests for within group comparisons of mean dorsal temperature between successive imaging periods, three patterns of temperature change were apparent during 10 min following typing. Controls further increased mean temperature by 0.1 degrees C ( t-test, P=0.001) at 3-5 min post-typing before a late temperature decline of -0.3 degrees C ( t-test, P=0.04), while cases without cold hands showed no change from initial post-typing mean temperature rise during middle or late periods. In contrast, subjects with keyboard-induced cold hands had no change from initial post-typing temperature until a decrease at the late period of -0.3 degrees C ( t-test, P=0.06). Infrared thermography appears to distinguish between the three groups of subjects, with keyboard-induced cold hand symptoms presumably due, at least partially, to reduced blood flow.

Coughlin P, Chetter IC, Kent PJ, Kester RC; St James’s University Hospital, Leeds, UK.

Br J Surg 1999 May;86(5):694-5

BACKGROUND: The hand-arm vibration syndrome (HAVS) is the commonest prescribed disease in the UK. Presently the diagnosis is subjective and the need for an objective investigation to support the diagnosis has been highlighted. This study analyses the potential of cold provocation thermography (CPT) to fulfil this role. METHODS: CPT was performed in ten controls (five men, five women; median age 35 (range 24-78) years) and 21 patients with HAVS (20 men, one woman; median age 45 (range 29-81) years). With an infrared camera, a precooling (PC) image was taken and then, following hand cooling in water at a temperature of 5 degrees C for 1 min, further rewarming images were taken every minute for 10 min. RESULTS: Patient finger tip temperatures were significantly cooler than control temperatures at all time points (P < 0.01, Student’s t test). The following Table shows the sensitivity, specificity and PPV of CPT. CONCLUSION: CPT provides strong objective evidence to support the clinical diagnosis of HAVS.

Gat Y, Bachar GN, Zukerman Z, Belenky A, Gorenish M.

Andrology Unit, Department of Obstetrics and Gynecology, Rabin Medical Center, Beilinson Campus, Petah Tiqva and Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.

Urol. 2004 Oct; 172(4 Pt 1):1239-40

PURPOSE: We evaluated the sensitivity of 3 noninvasive methods for detecting left and right varicoceles. MATERIALS AND METHODS: Three noninvasive methods for the detection of varicocele in the left and right internal spermatic veins were evaluated in 214 infertile men, namely, physical examination, scrotal contact thermography and ultrasound Doppler. Venography was used as the reference diagnosis. RESULTS: Varicocele was detected in 195 patients (91.1%), on the left side in 37 (19%), on the right side in 3 (1.5%) and bilaterally in 155 (79.5%). Scrotal contact thermography using varicoscreen proved to be the most accurate method. Sensitivity, specificity, accuracy and positive predictive value were 98.9%, 66.6%, 98.5% and 100%, respectively, for left varicocele, and 95.6%, 91.6%, 94.9% and 98%, respectively, for right varicocele. Doppler sonography was associated with the highest number of false-positive results. Accuracy in evaluating retrograde flow was lowest for both sides for physical examination and highest for the combination of Doppler sonography and contact thermography, with a sensitivity, specificity, accuracy and positive predictive value of 100%, 33.3%, 99.0% and 98.9%, respectively, for the left side, and 97.4%, 58.3%, 90.3% and 91.1%, respectively, for the right side. In 165 (85%) of the 195 patients who underwent internal spermatic vein embolization sperm parameters were improved. CONCLUSIONS: The present study yielded 2 major findings. Thermography is more sensitive and accurate for the detection of varicocele than Doppler ultrasound and physical examination, and it can be used for screening as a single modality in infertile men. Doppler ultrasound and thermography are complementary and their combined use yields the highest sensitivity and accuracy.

Gat Y, Zukerman Z, Chakraborty J, Gornish M.

Andrology Unit, Department of Obstetrics and Gynecology, Tel Aviv University, Israel.

BACKGROUND: Varicocele is a bilateral vascular disease, involving a network of collaterals and small, retroperitoneal bypasses. … It was considered a predominantly unilateral (left-sided) disease. Its pathophysiology has not been clearly delineated and the treatments offered do not seem to be effective. … Based on our findings (i) varicocele is a bilateral disease; (ii) the disease is expressed earlier in the left side and is more intense because the blood column is longer in the left side than the right; (iii) partial treatment to the left side only and ignoring bypasses is not adequate to correct the problem; … (vi) thermography alone or combined with ultrasonography with special attention to the bilaterality of the disease are the best non-invasive tools for its detection.

Watanabe Y. 

Department of Radiology, Kurashiki Central Hospital, Kurashiki, Japan.

Curr Opin Urol 2002 Mar;12(2):149-53

Color Doppler ultrasound has been the mainstay for the evaluation of the scrotum in a variety of clinical settings. However, ultrasonography results are not always accurate or conclusive. Despite the high cost and limited availability, magnetic resonance imaging with the dynamic contrast-enhanced subtraction technique provides accurate information on morphology as well as blood flow. Infrared scrotal thermography increases accuracy in the diagnosis of varicocele. This article attempts to summarize recent advances in scrotal imaging with regard to testicular and extratesticular disorders.

Varju G, Pieper CF, Renner JB, Kraus VB. Box 3416, Duke University Medical Center, Durham, NC 27710, USA.

Rheumatology (Oxford). 2004 Jul;43(7):915-9. Epub 2004 May 04.

OBJECTIVE: Anatomical stages of digital osteoarthritis (OA) have been characterized radiographically as progressing through sequential phases from normal to osteophyte formation, progressive loss of joint space, joint erosion and joint remodelling. Our study was designed to evaluate a physiological parameter, joint surface temperature, measured with computerized digital infrared thermal imaging, and its association with sequential stages of radiographic OA (rOA). METHODS: Thermograms, radiographs and digital photographs were taken of both hands of 91 subjects with nodal hand OA. Temperature measurements were made on digits 2-5 at distal interphalangeal (DIP) joints, proximal interphalangeal (PIP) joints and metacarpophalangeal (MCP) joints (2184 joints in total). We fitted a repeated measures ANCOVA model to analyse the effects of rOA on temperature, with handedness, joint group, digit and NSAID use as covariates. RESULTS: The reliability of the thermoscanning procedure was high (generalizability coefficient 0.899 for two scans performed 3 h apart). The mean joint temperature decreased with increasing rOA severity, defined by the Kellgren-Lawrence (KL) scale. The mean temperature of KL0 joints was significantly different from that of each of the other KL grades (P Joint surface temperature varied with the severity of rOA. Joints were warmer than normal at the onset of OA. As the severity of rOA worsened, joint surface temperature declined. These data support the supposition that digital OA progresses in phases initiated by an inflammatory process. The cooler surface temperatures in later stages of the disease may in part explain the paucity of symptoms reported by patients with hand OA.

Brenner M, Braun C, Oster M, Gulko PS.

North Shore-LIJ Research Institute, United States

Ann Rheum Dis. 2005 Sep 8;

OBJECTIVES: To determine the potential usefulness of a novel thermal imaging technology to evaluate and monitor inflammatory arthritis activity in small joints using rat models, and to determine whether thermal changes can be used to detect pre-clinical stages of synovitis. METHODS: Three different rat strains were studied in a monoarticular model of inflammatory arthritis of the ankle induced with an intra-articular (IA) injection of complete Freund’s adjuvant (CFA), and compared with the contra-lateral ankle injected with normal saline. Arthritis activity and severity scores, ankle diameters, pain related posture scores, and thermal images were obtained at ten different time-points between 0h (before induction) and day 7. The pristane-induced arthritis (PIA) model was used to study pre-clinical synovitis. Thermal images were obtained at each time-point using the TSA ImagIR System and digitally analyzed. RESULTS: Rats developed similar ankle arthritis detected 6h after the IA injection of CFA, which persisted for seven days. All ankle clinical parameters, including arthritis activity and severity scores, significantly correlated with ankle thermal imaging changes in the monoarthritis model (P<0.003). No thermal imaging changes were detected in pre-clinical stages of PIA. However, PIA onset coincided with increased ankle thermal signature. CONCLUSION:Thermal measurements significantly correlated with arthritis activity and severity parameters. This technology was highly sensitive and could directly measure two cardinal signs of inflammation (warmth and edema – based on ankle diameter) in an area (ankle) that is less than half the size of a human interphalangeal joint, suggesting a potential use to monitor drug responses of rheumatoid arthritis in drug trials or clinical practice.

Kwon YB, Kim JH, Yoon JH, Lee JD, Han HJ, Mar WC, Beitz AJ, Lee JH.

Department of Veterinary Physiology, College of Veterinary Medicine and School of Agricultural Biotechnology, Seoul National University, Suwon, Korea.

Am J Chin Med. 2001;29(2):187-99.

The aim of this investigation was to determine whether bee venom (BV) administered directly into an acupoint was a clinically effective and safe method for relieving the pain of patients with knee osteoarthritis (OA) as compared to traditional needle acupuncture. We evaluated the efficacy of BV acupuncture using both pain relief scores and computerized infrared thermography (IRT) following 4 weeks of BV acupuncture treatment. We observed that a significantly higher proportion of subjects receiving BV acupuncture reported substantial pain relief as compared with those receiving traditional needle acupuncture therapy. Furthermore, the IRT score was significantly improved and paralleled the level of pain relief.

Tunley BV, Henson FM; 

Queen’s Veterinary School Hospital, Department of Clinical Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge, Cambridgeshire CB3 0ES, UK.

Equine Vet J. 2004 May;36(4):306-12.

REASONS FOR PERFORMING STUDY: Thermographic imaging is an increasingly used diagnostic tool. When performing thermography, guidelines suggest that horses should be left for 10-20 mins to ‘acclimatise’ to the thermographic imaging environment, with no experimental data to substantiate this recommendation. In addition, little objective work has been published on the repeatability and reliability of the data obtained. Thermography has been widely used to identify areas of abnormal body surface temperature in horses with back pathology; however, no normal data is available on the thermographic ‘map’ of the thoracolumbar region with which to compare horses with suspected pathology. OBJECTIVES: To i) investigate whether equilibration of the thermographic subject was required and, if so, how long it should take, ii) investigate what factors affect time to equilibration, iii) investigate the repeatability and reliability of the technique and iv) generate a topographic thermographic ‘map’ of the thoracolumbar region. METHODS: A total of 52 horses were used. The following investigations were undertaken: thermal imaging validation, i.e. detection of movement around the baseline of an object of constant temperature; factors affecting equilibration; pattern reproducibility during equilibration and over time (n = 25); and imaging of the thoracolumbar region (n = 27). RESULTS: A 1 degrees C change was detected in an object of stable temperature using this detection system, i.e the ‘noise’ in the system. The average time taken to equilibrate, ie. reach a plateau temperature, was 39 mins (40.2 in the gluteal region, 36.2 in lateral thoracic region and 40.4 in metacarpophalangeal region). Only 19% of horses reached plateau within 10-20 mins. Of the factors analysed hair length and difference between the external environment and the internal environment where the measurements were being taken both significantly affected time to plateau (P<0.05). However, during equilibration, the thermographic patterns obtained did not change, nor when assessed over a 7 day period. A ‘normal’ map of the surface temperature of the thoracolumbar region has been produced, demonstrating that the midline is the hottest, with a fall off of 3 degrees C either side of the midline. CONCLUSIONS: This study demonstrates that horses may not need time to equilibrate prior to taking thermographic images and that thermographic patterns are reproducible over periods up to 7 days. A topographical thermographic ‘map’ of the thoracolumbar region has been obtained. POTENTIAL RELEVANCE: Clinicians can obtain relevant thermographic images without the need for prior equilibration and can compare cases with thoracolumbar pathology to a normal topographic thermographic map.

Van den Heuvel CJ, Ferguson SA, Dawson D, Gilbert SS.; 

The Centre for Sleep Research, University of South Australia, Level 5 Basil Hetzel Institute, The Queen Elizabeth Hospital, Woodville, SA 5011, Australia.

Physiol Meas. 2003 Aug;24(3):717-25.4

Body temperature regulation is associated with changes in sleep propensity; therefore, sleep research often necessitates concomitant assessment of core and skin surface temperatures. Attachment to thermistors may limit the range of movement and comfort, introducing a potential confound that may prolong sleep initiation or increase wakefulness after sleep onset. It has been suggested that contact thermometry may artificially increase temperatures due to insulation. We report here on a method of remote sensing skin temperatures using a digital infrared thermal imaging (DITI) system, which can reduce these potential confounds. Using data from four healthy young adult volunteers (age = 26.8 +/- 2.2 years; mean +/- SEM), we compared measures of skin temperature using a DITI system with contact thermometry methods already in use in our sleep laboratory. A total of 416 skin temperature measurements (T(sk)) were collected from various sites, resulting in an overall correlation coefficient of R = 0.99 (p < 0.0001) between both methods. Regression analyses for individuals resulted in correlation coefficients between 0.80 and 0.97. These pilot results suggest that DITI can assess skin surface temperatures as accurately as contact thermometry, provided the interest is in relative and not absolute temperature changes. This and some other important limitations are discussed in more detail hereafter.

Schmermund A, Rodermann J, Erbel R. Department of Cardiology, University Clinic Essen, Germany. Axel.

Herz. 2003 Sep;28(6):505-12.

Arteriosclerosis is an inflammatory disease. Inflammatory processes play a role in the initiation of plaque development and the early stages of the disease as well as in complex plaques and complications such as intraarterial thrombosis. A method to detect inflammation in coronary arteries has the potential to characterize both local and systemic activation of arteriosclerotic plaque disease. It could help to define in more detail what constitutes a vulnerable plaque or vulnerable vessel and thus improve the prediction of acute coronary syndromes. Intracoronary thermography records a cardinal sign of inflammation. Heat is probably produced by (activated) macrophages. Experimental work has suggested that thermal heterogeneity is present in arteriosclerotic plaques and that increased temperature is found at the site of inflammatory cellular-macrophage-infiltration. Preliminary experience in patients undergoing coronary angiography has demonstrated that it is safe and feasible to perform intracoronary thermography using various systems. A graded relationship between thermal heterogeneity and clinical symptoms has been reported, with the greatest temperature elevation in acute myocardial infarction. Increases in thermal heterogeneity appeared to be associated with a comparably unfavorable long-term prognosis. Intracoronary thermography has the potential to provide insights into location and extent of inflammation as well as the prognostic consequences. Currently, this novel method and the underlying concepts are extensively evaluated.

Bhatia V, Bhatia R, Dhindsa S, Dhindsa M.; Department of Internal Medicine, State University of New York at Buffalo, Buffalo, NY, USA.

South Med J. 2003 Nov;96(11):1142-7.

Atherosclerosis is currently considered to be an inflammatory and thus a systemic disease affecting multiple arterial beds. Recent advances in intravascular imaging have shown multiple sites of atherosclerotic changes in coronary arterial wall. Traditionally, angiography has been used to detect and characterize atherosclerotic plaque in coronary arteries, but recently it has been found that plaques that are not significantly stenotic on angiography cause acute myocardial infarction. As a result, newer imaging and diagnostic modalities are required to predict which of the atherosclerotic plaque are prone to rupture and hence distinguish “stable” and “vulnerable” plaques. Intravascular ultrasound can identify multiple plaques that are not seen on coronary angiography. Thermography has shown much promise and is based on the concept that the inflammatory plaques are associated with increased temperature and can also identify “vulnerable patients.” Of all these newer modalities, magnetic resonance imaging has shown the most promise in identification and characterization of vulnerable plaques. In this article, we review the newer coronary artery imaging modalities and discuss the limitations of traditional coronary angiography.

Gordon N, Rispler S, Sideman S, Shofty R, Beyar R;

 Heart System Research Center, Department of Biomedical Engineering, Technion-IIT, Haifa, Israel.

Med Eng Phys 1998 Sep;20(6):443-51

Intraoperative thermographic imaging in open-chest conditions can provide the surgeon with important qualitative information regarding coronary flow by utilizing heat transfer analysis following injection of cold saline into the aortic root. The heat transfer model is based on the assumption that the epicardial temperature changes are mainly due to convection of heat by the blood flow, which may, therefore, be estimated by measuring the temperature variations. Hearts of eight dogs were exposed and imaged by a thermographic camera. Flow in the left arterial descending (LAD) coronary branch was measured by a transit-time flowmeter. 20 ml of cold saline were injected into the aortic root (just after the aortic valve) and the epicardial temperature images were recorded at end-diastole, for 20-30 s. Different flow rates were achieved by 1 min occlusion of the LAD, which affected a reactive hyperemic response. The dynamics of the temperature in the arterial coronary tree was obtained by averaging the temperature over an edge-detected arterial segment for each frame. The heat transfer equation was curve-fitted, and the flow-dependent heat transfer index was correlated with the experimentally determined coronary flow (r = 0.69, p < 0.001). In summary: a method for quantitative estimation of coronary blood flow by thermography and heat transfer analysis was developed and tested in animal experiments. This method can provide important information regarding coronary blood flow during open-chest surgical procedures.

Gehani AA, Rees MR; 

Cardiac Research Unit, Killingbeck Hospital, Leeds, United Kingdom.

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

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.

Okada Y, Kawamata T, Kawashima A, Hori T 

Department of Neurosurgery, Tokyo Women’s Medical University, Tokyo, Japan.

Neurosurgery. 2007 Apr;60(4 Suppl 2):362-5;

OBJECTIVE: The extracranial-intracranial bypass may have the potential to improve hemodynamic cerebral ischemia caused by occlusive diseases of the main cerebral arteries. Intraoperative confirmation of effective distribution of blood flow via the donor arteries to the involved region will assure a successful bypass surgery. METHODS: Infrared thermography was used to measure the temperature of the cortical surface at the operative field. Regional cerebral blood flow (rCBF) was measured with a laser Doppler flow meter. Changes in the cortical surface temperature before and after temporary occlusion of the bypass were compared with changes in rCBF values in the corresponding sites. RESULTS: Thermographic examination demonstrated a heterogeneous increase of cortical surface temperature caused by the blood flow via the extracranial-intracranial bypass and was closely related to rCBF changes. CONCLUSION: Thermography is useful not only to demonstrate the distribution of blood flow through the extracranial-intracranial bypass but also to quantitatively evaluate the rCBF changes in the operative field.

Gorbach AM, Heiss JD, Kopylev L, Oldfield EH.

National Institute of Neurological Disorders and Stroke, Bioengineering and Physical Science, Warren Grant Magnuson Clinical Center, National Institutes of Health, Bethesda, Maryland 20892-5766, USA.

J Neurosurg. 2004 Dec;101(6):960-9.

Although clinical imaging defines the anatomical relationship between a brain tumor and the surrounding brain and neurological deficits indicate the neurophysiological consequences of the tumor, the effect of a brain tumor on vascular physiology is less clear. … Brain tumors induce changes in cerebral blood flow (CBF) in the cortex, which can be made visible by performing infrared imaging during cranial surgery. A reduction in CBF beyond the tumor margin improves after removal of the lesion.

Ecker RD, Goerss SJ, Meyer FB, Cohen-Gadol AA, Britton JW, Levine JA. Department of Neurological Surgery, Mayo Clinic and Foundation, Rochester, Minnesota, USA.

J Neurosurg 2002 Dec;97(6):1460-71

High-resolution dynamic infrared (DIR) imaging provides intraoperative real-time physiological,

anatomical, and pathological information; however, DIR imaging has rarely been used in neurosurgical patients. The authors report on their initial experience with intraoperative DIR imaging in 30 such patients. A novel, long-wave (8-10 micron), narrow-band, focal-plane-array infrared photodetector was incorporated into a camera system with a temperature resolution of 0.006 degrees C, providing 65,000 pixels/frame at a data acquisition rate of 200 frames/second. Intraoperative imaging of patients was performed before and after surgery. Infrared data were subsequently analyzed by examining absolute differences in cortical temperatures, changes in temperature over time, and infrared intensities at varying physiological frequencies. Dynamic infrared imaging was applied in a variety of neurosurgical cases. After resection of an arteriovenous malformation, there was postoperative hyperperfusion of the surrounding brain parenchyma, which was consistent with a loss of autoregulation. Bypass patency and increased perfusion of adjacent brain were documented during two of three extracranial-intracranial bypasses. In seven of nine patients with epilepsy the results of DIR imaging corresponded to seizure foci that had been electrocorticographically mapped preoperatively. Dynamic infrared imaging demonstrated the functional cortex in four of nine patients undergoing awake resection and cortical stimulation. Finally, DIR imaging exhibited the distinct thermal footprints of 14 of 16 brain tumors. Dynamic infrared imaging may prove to be a powerful adjunctive intraoperative diagnostic tool in the neurosurgical imaging armamentarium. Real-time assessment of cerebral vessel patency and cerebral perfusion are the most direct applications of this technology. Uses of this imaging modality in the localization of epileptic foci, identification of functional cortex during awake craniotomy, and determination of tumor border and intraoperative brain shift are avenues of inquiry that require further investigation.

Gati I, Papp L, Polgar T

Department of Neurology, University of Pecs Medical School, Hungary.

APMIS, 1997 Oct; 105(10):801-805

Human brains, removed at routine autopsy, were subjected to neuropathological investigation. The usual gross morphological investigation of the brains was extended to include the detection of their infrared emissions. Fundamental structures, such as the grey and white matter, were separated on the infrared images. Furthermore, pathological processes, such as ischaemic damage, haemorrhage, and sclerotic plaques, hardly seen on the normal photographs, gave a strong signal on the infrared pictures. These pilot experiments demonstrated that infrared detection is a reproducible method in this type of biomedical application, and potentially a very useful tool in macroscopic pathology.

Espinosa ML, Santiago S, Guzman JJ, Prieto J, Ferrer T;

Laboratorio de SNA, Hospital General La Paz, Madrid, Espana.

Rev Neurol 1999 Mar 16-31;28(6):535-43

INTRODUCTION: Standard neurophysiological techniques evaluate thick myelinated fibers. Yet, peripheral nerves are equally composed of thin myelinated and unmyelinated fibers. The latter are responsible for autonomic function as well as temperature and pain perception. DEVELOPMENT: Microneurographic studies are restricted to investigation laboratories. Since the techniques are complex and invasive, their performance is still poor for clinical purposes and some of the components to be analyzed, such as cardiovagal, cannot be directly recorded. The clinical need to evaluate the functions regulated by the autonomic nervous system (ANS) had led to devising a series of tests which, in most cases, rely on reflex responses evoked by already known standardize stimuli. The battery chosen has to be non invasive, reproducible, specific, providing relevant data to the investigated function, with a readily available technology, which has to be managed being aware of the physiological and pathological factors that might bear an influence on the results. The recent development of heart rate blood pressure power spectral analysis, provides a new interesting insight for quantification of ANS abnormalities. The study of thermography and thermometry of body surface brings forward evidence on the activity of other thin and unmyelinated fibers components of the peripheral nerve spectrum. CONCLUSION: The adequate management of the above mentioned tests gives rise to a more extensive and appropriate knowledge of the whole peripheral nerve fiber spectrum.

Christidis I, Zotter H, Rosegger H, Engele H, Kurz R, Kerbl R.

Department of Pediatrics, University of Graz, Austria.

Gynakol Geburtshilfliche Rundsch 2003;43(1):31-5

OBJECTIVE: It was the aim of this study to investigate the surface temperature in newborns within the first hour after delivery. Furthermore, the influence of different environmental conditions with regard to surface temperature was documented. METHODS: Body surface temperature was recorded under several environmental conditions by use of infrared thermography. 42 newborns, all delivered at term and with weight appropriate for date, were investigated under controlled conditions. RESULTS: The surface temperature immediately after birth shows a uniform picture of the whole body; however, it is significantly lower than the core temperature. Soon after birth, peripheral sites become cooler whereas a constant temperature is maintained at the trunk. Bathing in warm water again leads to a more even temperature profile. Radiant heaters and skin-to-skin contact with the mother are both effective methods to prevent heat loss in neonates. CONCLUSIONS: Infrared thermography is a simple and reliable tool for the measurement of skin temperature profiles in neonates. Without the need of direct skin contact, it may be helpful for optimizing environmental conditions at delivery suites and neonatal intensive-care units.” Ref. S. Karger AG, Basel

Horns KM;

College of Nursing, NBICU, University of Utah, Salt Lake City, USA.

J Perinat Neonatal Nurs 2000 Mar;13(4):50-66

Septicemia is a growing problem among low birth weight infants. Early identification and treatment of sepsis in these infants would help to reduce the high mortality and morbidity seen with this disorder. Newer techniques may make earlier diagnosis a reality. In the following review article, early-onset sepsis in the premature infant is described, specifically focusing on the neonatal inflammatory response, neutropenia, and its somewhat inconsistent and delayed role as a marker for sepsis risk factors. Physiological signs, laboratory indicators, skin temperature, peripheral perfusion, and the interaction of macro-environmental factors are also discussed. Newer (neoteric) immunologic and cytokine markers of sepsis are reviewed. Finally, thermography, a noninvasive bioinstrument measuring vasoactive peripheral perfusion, which has potential for early recognition of neonatal septicemia, is described.

Zhang HY, Kim YS, Cho YE;

Department of Neurosurgery, Yongdong Severance Hospital, Yonsei College of Medicine, Seoul, Korea.

Yonsei Med J 1999 Oct;40(5):401-12

Subjective symptoms of a cool or warm sensation in the arm could be shown objectively by using of thermography with the detection of thermal change in the case of radiculopathy, including cervical disc herniation (CDH). However, the precise location of each thermal change at CDH has not been established in humans. This study used digital infrared thermographic imaging (DITI) for 50 controls and 115 CDH patients, analyzed the data statistically with t-test, and defined the areas of thermatomal change in CDH C3/4, C4/5, C5/6, C6/7 and C7/T1. The temperature of the upper trunk and upper extremities of the control group ranged from 29.8 degrees C to 32.8 degrees C. The minimal abnormal thermal difference in the right and left upper extremities ranged from 0.1 degree C to 0.3 degree C in 99% confidence interval. If delta T was more than 0.1 degree C, the anterior middle shoulder sector was considered abnormal (p < 0.01). If delta T was more than 0.3 degree C, the medial upper aspect of the forearm and dorsal aspect of the arm, some areas of the palm and anterior part of the fourth finger, and their opposite side sectors and all dorsal aspects of fingers were considered abnormal (p < 0.01). Other areas except those mentioned above were considered abnormal if delta T was more than 0.2 degree C (p < 0.01). In p < 0.05, thermal change in CDH C3/4 included the posterior upper back and shoulder and the anterior shoulder. Thermal change in CDH C4/5 included the middle and lateral aspect of the triceps muscle, proximal radial region, the posterior medial aspect of the forearm and distal lateral forearm. Thermal change in CDH C5/6 included the anterior aspects of the thenar, thumb and second finger and the anterior aspects of the radial region and posterior aspects of the pararadial region. Thermal change in CDH C6/7 included the posterior aspect of the ulnar and palmar region and the anterior aspects of the ulnar region and some fingers. Thermal change in CDH C7/T1 included the scapula and posterior medial aspect of the arm and the anterior medial aspect of the arm. The areas of thermal change in each CDH included wider sensory dermatome and sympathetic dermatome There was a statistically significant change of temperature in the areas of thermal change in all CDH patients. In conclusion, the areas of thermal change in CDH can be helpful in diagnosing the level of disc protrusion and in detecting the symptomatic level in multiple CDH patients.

Fushimi H, Kubo M, Inoue T, Yamada Y, Matsuyama Y, Kameyama M;

Department of Medicine, Sumitomo Hospital, Osaka, Japan.

Diabetes Res Clin Pract 1998 Oct;42(1):29-34

Analyses of direct effects of smoking on peripheral arteries were done using thermography, blood fluorometry and echography on 97 habitual smoker-diabetics without triopathy. There were found to be four types of thermographic changes following smoking, which varied according to the degree of atherosclerosis of the artery. The smoking-stimulated thermographic pattern in the control group of healthy volunteers was a small wavy pattern, fluctuating along the base line every few minutes within a temperature range of 1.0-1.5 degrees C (N type). In diabetics, four types of thermographic patterns were produced: normal (N) type as control, increasing (I) type (increasing in skin temperature), decreasing (D) type (decreasing in temperature), and F type (no changes in temperature). The most significant finding was the decreasing pattern which closely connected to clinical and echographic aspects of macroangiopathic changes. The increasing type was characterized by a paradoxical increase in temperature after smoking in order diabetics with good blood glucose control and who were less atherosclerotic. Blood flow was correlated to the skin temperature at the base state and changes after smoking. Moreover, blood flow changes measured by fluorometry suggest that vasoconstriction or vasodilatation following smoking took place. These results suggest that this smoking test might be a good tool for diagnosing for the degree of atherosclerosis and for its following up.

Bornmyr S, Svensson H.;

Department of Clinical Physiology, Allmanna Sjukhuset, Malmo, Sweden.

Clin Physiol 1991 Mar;11(2):135-41

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.

Roback K.

Center for Medical Technology Assessment (CMT), Department of Medical and Health Sciences, Linköping University, Linkoping, Sweden.

Expert Rev Med Devices. 2010 Sep;7(5):711-8.

Diabetic foot complications are associated with substantial costs and loss of quality of life. This article gives an overview of available and emerging devices for the monitoring of foot temperature as a means of early detection of foot disorders in diabetes. The aim is to describe the technologies and to summarize experiences from experimental use. Studies show that regular monitoring of foot temperature may limit the incidence of disabling conditions such as foot ulcers and lower-limb amputations. Infrared thermometry and liquid crystal thermography were identified as the leading technologies in use today. Both technologies are feasible for temperature monitoring of the feet and could be used as a complement to current practices for foot examinations in diabetes.

Harding, J. Richard; Barnes, Kathryn M.;

Department of Clinical Radiology, St Woolos Hospital, Glan Hafren NHS Trust, Newport, Gwent, U.K.

Deep Vein Thrombosis: Proceedings – 19th International Conference – IEEE/EMBS 

Oct. 30-Nov. 2, 1997 Chicago, IL

In view of the many advantages compared with venography or Doppler ultrasound, and the ability to avoid the necessity for over one third of these investigations, thermal imaging should be considered the initial investigation of choice in clinically suspected DVT, proceeding to venography or Doppler ultrasound only when thermal imaging is positive. There are risks and disadvantages to the most commonly utilised conventional tests for DVT, over one third of which examinations can be avoided by performing thermal imaging as the initial investigation, which excludes DVT when normal. This outcome study followed up patients with clinically suspected DVT who were not further investigated or treated following normal thermal imaging, and showed that no patients developed PE (pulmonary embolism) following normal thermography with no further investigation for DVT and withholding of anticoagulant therapy.

Neundorfer B, Handwerker HO;

Neurologische Klinik, Lang E, Claus D, Friedrich-Alexander-Universitat Erlangen-Nurnberg, Germany.

Pain 1995 Mar;60(3):295-302

Pain intensity in carpal tunnel syndrome (CTS) was correlated with neuro- and psychophysiological parameters related to the function of different nerve fiber classes within the median nerve in 23 patients. Control data were obtained from 16 normal subjects. Mean intensity of all pain attacks which occurred 14 days before surgical treatment was assessed on visual analogue scales (average CTS pain). Functions of thick myelinated nerve fibers were determined by motor and sensory nerve conduction studies. Functions of thin myelinated and unmyelinated nerve fibers were evaluated by measuring thresholds of warmth, cold and heat pain on the index and little finger. Pain intensity and neurogenic vasodilatation following noxious mechano-stimulation on the interdigital web between index and middle finger provided additional information on the functioning of nociceptive nerve fibers. Sympathetic reflexes induced by these painful stimuli were assessed by means of infrared thermography and photoplethysmography. Mean intensity of pain attacks (40 +/- 19% VAS) correlated significantly with latency (r = 0.58, P < 0.01) and amplitude (r = -0.50, P < 0.01) of the compound action potential from abductor pollicis brevis muscle following distal median nerve stimulation. Thresholds of warmth, cold and heat pain on index finger were significantly increased during CTS when compared to the control subjects. The magnitude of neurogenic vasodilatation and sympathetic vasoconstrictor reflexes were not significantly different. Average CTS pain correlated inversely to the threshold of heat pain on index (r = -0.46, P < 0.05), but also on the little finger (r = -0.41, P < 0.05), which is not innervated by the median nerve.

Oerlemans HM, Graff MJ, Dijkstra-Hekkink JB, de Boo T, Goris RJ, Oostendorp RA;

Allied Health Services, University Hospital Nijmegen, The Netherlands.

J Hand Ther 1999 Oct-Dec;12(4):284-90

Recording asymmetry in skin temperature between symmetric body areas is useful in monitoring diseases that alter skin temperature. This pilot study checked the reported high reliability of recording skin temperature of the hands with an infrared tympanic thermometer, provided insight into the relationship between dorsal and palmar temperature differences, and assessed the agreement between these data and normative data obtained from thermograms. Using an infrared tympanic thermometer, two independent assessors measured the temperature of 13 asymptomatic, right-handed subjects (mean age, 30 years; range, 21 to 44 years). Both test-retest and interobserver reliabilities were high. Skin temperature of the hand differed with the site where it was measured; differences between sites changed over time. The mean absolute differences in skin temperature between dorsal and palmar aspects of the hands were 0.30 degrees C and 0.25 degrees C, respectively. These data match normative values reported in the literature for infrared thermograms.

Arora N, Martins D, Ruggerio D, Tousimis E, Swistel AJ, Osborne MP, Simmons RM

Department of Surgery, New York Presbyterian Hospital-Cornell, New York, NY Am J Surg. 2008 Oct;196(4):523-6.

BACKGROUND: Digital infrared thermal imaging (DITI) has resurfaced in this era of modernized computer technology. Its role in the detection of breast cancer is evaluated. METHODS: In this prospective clinical trial, 92 patients for whom a breast biopsy was recommended based on prior mammogram or ultrasound underwent DITI. Three scores were generated: an overall risk score in the screening mode, a clinical score based on patient information, and a third assessment by artificial neural network. RESULTS: Sixty of 94 biopsies were malignant and 34 were benign. DITI identified 58 of 60 malignancies, with 97% sensitivity, 44% specificity, and 82% negative predictive value depending on the mode used. Compared to an overall risk score of 0, a score of 3 or greater was significantly more likely to be associated with malignancy (30% vs 90%, P < .03). CONCLUSION: DITI is a valuable adjunct to mammography and ultrasound, especially in women with dense breast parenchyma.

Agnese DM.

The Ohio State University, Columbus, Ohio.

Surg Technol Int. 2005;14:51-6.

Although mammography remains the most widely used tool for the early detection of breast cancers and evaluation of palpable abnormalities, a number of other imaging tools are being developed and used. Ultrasonography (US) is an excellent adjunct to conventional mammography. In addition to identifying solid and cystic abnormalities, US can often distinguish benign and malignant solid nodules. Magnetic resonance imaging (MRI) also is useful in assessing the extent of disease within the breast, particularly in women with dense breasts. MRI may be a more sensitive screening tool in women at elevated breast cancer risk. Newer techniques based on the metabolic activity of breast tumors also have been developed. One such technique is scintimammography, which uses radiolabeled tracers to detect breast malignancies. Positron emission tomography (PET), which relies on the high metabolic rate of tumors, also has been described as a method to evaluate breast disease. Other techniques, such as optical tomography and thermography, rely on angiogenesis and generated heat to identify cancers. These and other tools may help to improve both the sensitivity and specificity of cancer detection. Ideally, this improved detection results in improved outcomes in those who have breast cancer and avoidance of unnecessary procedures in those who do not.

Hu L, Gupta A, Gore JP, Xu LX.;

School of Mechanical Engineering, Purdue University, West Lafayette, IN 47907, USA.

J Biomech Eng. 2004 Apr;126(2):204-11.

A bioheat-transfer-based numerical model was utilized to study the energy balance in healthy and malignant breasts subjected to forced convection in a wind tunnel. Steady-state temperature distributions on the skin surface of the breasts were obtained by numerically solving the conjugate heat transfer problem. Parametric studies on the influences of the airflow on the skin thermal expression of tumors were performed. It was found that the presence of tumor may not be clearly shown due to the irregularities of the skin temperature distribution induced by the airflow field. Nevertheless, image subtraction techniques could be employed to eliminate the effects of the flow field and thermal noise and significantly improve the thermal signature of the tumor on the skin surface. Inclusion of the possible skin vascular response to cold stress caused by the airflow further enhances the signal, especially for deeply embedded tumors that otherwise may not be detectable. Int J Fertil Womens Med 2001

Keith LG, Oleszczuk JJ, Laguens M.;

Department of Obstetrics and Gynecology, Northwestern University Medical School, Chicago, Illinois, USA.

Int J Fertil Womens Med 2001 Sep-Oct;46(5):238-47

The most disappointing aspect of breast cancer treatment as a public health issue has been the failure of screening to improve mortality figures. Since treatment of late-stage cancer has indeed advanced, mortality can only be decreased by improving the rate of early diagnosis. From the mid-1950s to the mid-1970s, it was expected that thermography would hold the key to breast cancer detection, as surface temperature increases overlying malignant tumors had been demonstrated by thermographic imaging. Unfortunately, detection of the 1-3 degrees C thermal differences failed to bear out its promise in early identification of cancer. In the intervening two-and-a-half decades, three new factors have emerged: it is now apparent that breast cancer has a lengthy genesis; a long-established tumor-even one of a certain minimum size-induces increased arterial/capillary vascularity in its vicinity; and thermal variations that characterize tissue metabolism are circadian (“about 24 hours”) in periodicity. This paper reviews the evidence for a connection between disturbances of circadian rhythms and breast cancer. Furthermore, a scheme is proposed in which circadian rhythm “chaos” is taken as a signal of high risk for breast cancer even in the absence of mammographic evidence of neoplasm or a palpable tumor. Recent studies along this line suggest that an abnormal thermal sign, in the light of our present knowledge of breast cancer, is ten times as important an indication as is family history data.

Sekine H, Kobayashi M, Honda C, Aoki M, Nakagawa M, Kanehira C;

Department of Radiology, Division of Radiotherapy, The Jikei University School of Medicine, 3-25-8 Nishi-Shinbashi, Minato-ku, Tokyo 105-8461, Japan.

Breast Cancer 2000 Apr 25;7(2):142-148

BACKGROUND: The temperature of the skin remains elevated long after breast-conserving treatment with irradiation, perhaps because evaporative cooling is impaired. We investigated physiological changes of the irradiated skin and reevaluated the radiosensitivity of sweat glands on a functional basis to determine whether severe complications can be predicted. METHODS: Breast and axillary skin temperatures were measured with thermography and sweat production in response to local thermal stimuli was measured on the basis of changes in electrical skin resistance with a bridge circuit in 45 women before, during, and after breast irradiation for breast cancer. RESULTS: Breast and axillary temperatures were significantly increased after irradiation. In response to cutaneous thermal stimuli, the electric skin resistance of nonirradiated areas decreased significantly because of sweating, but that of irradiated areas was unchanged. CONCLUSION: Impairment of sweating may play an important role in skin damage after irradiation. Although glandular tissue is not usually radiosensitive, the results of our functional assessment suggest that sweat glands are more radiosensitive than expected.

Department of Oncology, St. Mary’s Hospital, Montreal, Quebec; Department of Radiotherapy, London Cancer Center, London, Ontario; and Ville Marie Breast and Oncology Center, Montreal, Quebec, Canada.

The Breast Journal, Volume 4, Number 4, 1998, 245-251

Our initial experience would suggest that, when done concomitantly with clinical exam and mammography, high-resolution digital infrared imaging can provide additional safe, practical, and objective information. Our initial reappraisal would also suggest that infrared imaging, based more on process than structural changes and requiring neither contact, compression, radiation nor venous access, can provide pertinent and practical complementary information to both clinical exam and mammography, our current primary basic detection modalities.

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.

Dent Mater J. 2003 Dec;22(4):436-43.

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.

Cummings M, Biagioni P, Lamey PJ, Burden DJ;

Division of Orthodontics, School of Clinical Dentistry, Queen’s University of Belfast, UK.

Eur J Orthod 1999 Apr;21(2):111-8

This study used modern thermal imaging techniques to investigate the temperature rise induced at the pulpal well during thermal debonding of ceramic brackets. Ceramic brackets were debonded from vertically sectioned premolar teeth using an electrothermal debonding unit. Ten teeth were debonded at the end of a single 3-second heating cycle. For a further group of 10 teeth, the bracket and heating element were left in contact with the tooth during the 3-second heating cycle and the 6-second cooling cycle. The average pulpal wall temperature increase for the teeth debonded at the end of the 3-second heating cycle was 16.8 degrees C. When the heating element and bracket remained in contact with the tooth during the 6-second cooling cycle an average temperature increase of 45.6 degrees C was recorded.

Gratt BM, Anbar M

Section of Oral Radiology, UCLA School of Dentistry 90095-1668, USA.

Dentomaxillofac Radiol 1998 Mar;27(2):68-74

Selected clinical applications using thermal imaging as an aid in dentistry are reviewed. Facial skin temperature can easily be measured in a clinical setting, without direct skin contact, by monitoring the emitted infrared radiation. This is the basis of static area telethermography (SAT) and dynamic area telethermography (DAT). SAT has recently been shown to be of help to the dentist in (1) the diagnosis of chronic orofacial pain, (2) as a unique tool in assessment of TMJ disorders, (3) as an aid in assessment of inferior alveolar nerve deficit, and (4) as a promising research tool. DAT, recently made possible by advances in computing technology combined with advanced infrared sensor technology, extracts quantitative information about hemodynamic processes from hundreds to thousands of digital thermal images of the affected facial areas, measured and collected within less than 3 min. DAT has promise of offering a better insight into aberrations of the neuronal control of facial skin perfusion and aiding our understanding of the correlation between orofacial pain and facial thermal abnormalities. This promising new insight may help in the management of orofacial pain.

Agarwal-Kozlowski K, Lange AC, Beck H.

Center for Palliative Care and Pain Management, Doerenberg Medical Center, Bad Iburg, Germany.

Anesthesiology. 2009 Sep;111(3):632-9.

BACKGROUND:

Although evidence of its effects is tentative, acupuncture has long been used in the treatment of multiple maladies. So far, it has not been possible to discriminate the effects of the venue from specific results of needling itself, thus physicians merely depend on patients’ statements. The authors investigated the efficacy of infrared thermography in distinguishing response to true acupuncture as compared to nonacupoint cutaneous and muscular needling (sham or minimal acupuncture), as well as without manipulation.

METHODS:

Thermographic imaging was performed in 50 healthy volunteers randomly assigned to four groups: Acupuncture of Hegu (LI 4), needling of a cutaneous and a muscular point where no acupuncture point has been described yet, and without manipulation. In a crossover protocol, each proband completed all four arms of the protocol in a random order. Infrared thermograms were gathered at defined points in each group.

RESULTS:

A significant increase in surface temperature occurred within 2 min after needling the acupuncture point Hegu (from 30.1 +/- 2.7 degrees C [SD] to 31.2 +/- 3.0 degrees C and to 31.9 +/- 2.5 degrees C after 10 min, P < 0.001), whereas needling of the cutaneous and muscular point, as well as without any manipulation resulted in a decrease of temperature in the monitored area.

CONCLUSION:

Contact-free infrared thermographic imaging is a reliable and easy-to-handle tool to distinguish between needling at Hegu and needling of a nonacupoint (“sham” acupuncture).

Yang HQ, Xie SS, Hu XL, Chen L, Li H.

Key Laboratory of OptoElectronic Science and Technology for Medicine of Ministry of Education, Institute of Laser and OptoElectronics Technology, Fujian Normal University, Fuzhou 350007, China.

Am J Chin Med. 2007;35(2):231-40

“The meridians and acupoints of human bodies at natural condition are investigated among 30 healthy volunteers by infrared thermal imaging technique. The results give clear evidence of the existence of infrared radiant tracks along human meridian courses. The time dependent evolution of the infrared radiant track is observed for the first time. The time rhythm of acupoints is also studied. Our findings not only support the view that infrared radiant tracks along human meridian courses is a normal vital and physiological phenomenon appearing in human beings, but also offer a potential method for noninvasive diagnostic by studying the physiological function and pathological change of meridians or acupoints by means of thermography.”

Zhang D; Wei Z; Wen B; Gao H; Peng Y; Wang F.

Journal of Traditional Chinese Medicine, 1991 Jun, 11(2):139-45

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.

Schnell HM, Zaspel JG.

Department of Surgery, Klinikum Grosshadern, Ludwig-Maximilians-University, Munich, Germany.

Burns. 2007 Oct 4;

This pilot study was designed to verify whether the spraying of coolant improves initial cooling in extensive burns. The cooling effects of 1l of sprayed water and 5l of poured water (at 22 degrees C) were tested; 53 healthy participants were cooled for 15min over 18% of their total body surface, twice. Thermographic imaging measured the loss of skin temperature and assessed the homogeneity of cooling. With sprayed coolant the mean decrease of skin temperature was significantly higher (p<0.003) throughout the entire cooling period and more homogeneous for the first 9min (p<0.003), compared with poured coolant. Infrared tympanic thermometry estimated core body temperature; neither poured nor sprayed water caused hypothermia. Even with a fifth of the volume of poured water, sprayed water cooled more efficiently. Thus, we conclude that spraying of coolant improves initial management.

Burns, 1996 Feb;22(1):26-28

The thermographic assessment of burns using infrared imaging has previously been shown to be a useful aid in the estimation of burn depth. In this study, thermographic images of burns, obtained from 65 patients over a 4-year period, were reviewed. … The results of this study suggest that thermography of burns, to assess depth, should be performed within 3 days following the injury.

Annals of Plastic Surgery, 1995 May;34(5):507-11.

Conclusion: clinically, preoperative recovery-enhanced thermography is useful for the design of perforator-based flaps.

Burns, 1991 Apr;17(2):117-22.

Thermographic assessment of damage to skin blood vessels caused by thermal injury correlates with healing time of burn wounds. NOTE: clever technique of using PVC film (Saran Wrap or Glad Wrap) shown to abolish the artifacts of evaporative water loss from the wound without interfering with surface imaging.

Burns, 1993 Jun;19(3):187-91.

The non-ionic surfactant Pluronic F-127 shows a positive therapeutic effect on wound closure rates and healing. Between 90 min. and 48 hours postinjury, thermography showed the alterations in the F-127 treated injuries.

Memarian N, Venetsanopoulos AN, Chau T.

Institute of Biomaterials and Biomedical Engineering, University of Toronto, Toronto, Canada.

J Neuroeng Rehabil. 2009 Apr 16;6:11.

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

Kastl KG, Wiesmiller KM, Lindemann J.

Department of Otorhinolaryngology, University of Ulm, Ulm, Germany.

Rhinology. 2009 Mar;47(1):89-92.

OBJECTIVE:

The surface temperature distribution within the nasal vestibule and the nasal cavity strongly depends on the exact intranasal detection site and point of time during the respiratory cycle. Therefore, conventional temperature measurements e.g. with thermocouples only provide selective measurements. The use of infrared thermography cameras could present a new contactless method with a high spatiotemporal resolution. The aim of the present study was to evaluate the use of infrared thermography camera systems for measurements of the nasal surface temperature during respiration.

METHODS:

The surface temperature profiles within the nasal vestibules of healthy volunteers were recorded with infrared thermography cameras during several breathing cycles. Two different types of infrared thermography standard systems were used.

RESULTS:

The recordings allowed a display of temperature alterations within the nasal vestibules in a high spatiotemporal resolution synchronous to the breathing cycle. During inspiration, the vestibular surface cooled down presenting a non-homogenous distribution (range, 24.7 to 30.2 degrees C). During expiration, the vestibular surface was warmed again with a non-homogenous distribution (range, 33.1 to 36.2 degrees C). The results of both camera systems were comparable.

CONCLUSION:

Infrared thermography cameras allow the exact mapping of nasal surface temperature within the nasal vestibules with a high spatiotemporal resolution without surface contact.

Song C, Appleyard V, Murray K, Frank T, Sibbett W, Cuschieri A, Thompson A.

Department of Surgery and Molecular Oncology, University of Dundee, Scotland.

Int J Cancer. 2007 May 8;

“…Here we tested the hypothesis that thermal imaging might represent a useful adjunctive technique in monitoring the growth dynamics of human tumor xenografts….In one case, a smaller secondary tumor, otherwise undetectable, was clearly evident by thermal imaging. The tumors were cooler than the surrounding tissue with a maximum temperature reduction of 1.5 degrees C for MDA-MB-231 tumor and 3 degrees C for MCF7 tumors observed on day 14….It was demonstrated that thermographic imaging could detect temperature changes as small as 0.1 degrees C on the skin surface at an early stage of tumor development. The findings of the study indicate that thermographic imaging might have considerable potential in monitoring human tumor xenografts and their response to anticancer drugs.”

Brooks JP, Perry WB, Putnam AT, Karulf RE

Department of Colorectal Surgery, Wilford Hall Medical Center, San Antonio, Texas, USA.

Dis Colon Rectum 2000 Sep;43(9):1319-21

PURPOSE: The aim of this study was to introduce thermal imaging in the intraoperative detection of bowel ischemia by comparing thermal imaging with conventional techniques in detecting acutely ischemic bowel, using histologic evidence for intestinal necrosis as the standard. METHODS: A prospective study was performed using a porcine model. Laparotomy was performed on four pigs under general anesthesia. A 25-cm segment of mid jejunum was tagged with proximal and distal sutures, and its mesentery was ligated and divided. Thermal imaging, visual inspection, Doppler ultrasound, and fluorescence with Wood’s lamp after fluorescein were used to estimate the extent of bowel ischemia five minutes after ligation of the mesentery. Measurements were taken in reference to both the proximal and distal tags to obtain two data points per animal for each method. After two hours of warm ischemia, the jejunum was harvested and sectioned longitudinally. Comparisons were made between the estimated region of necrosis for each method and microscopic evidence of necrosis. RESULTS: Visual inspection was the only method unable to detect a difference between vascularized and devascularized bowel for each of the eight data points. Fluorescein dye missed 3 cm of ischemic bowel. Doppler ultrasound and thermal imaging were 100 percent sensitive for necrotic bowel, with thermal imaging overestimating necrosis to a greater extent than Doppler ultrasound. The positive predictive value of fluorescein dye, Doppler ultrasound, and thermal imaging for determining nonviable bowel was 91.8, 80.8, and 69.5 percent, respectively. CONCLUSIONS: Thermal imaging has the potential to be a useful adjunct in the intraoperative determination of bowel ischemia. Further studies are indicated to study this technique.

Shastri D, Tsiamyrtzis P, Pavlidis I.

Computational Physiology Lab, University of Houston, Houston, TX

We propose a novel method that localizes the thermal footprint of the facial and ophthalmic arterial-venous complexes in the periorbital area. This footprint is used to extract the mean thermal signal over time (periorbital signal), which is a correlate of the blood supply to the ocular muscle. Previous work demonstrated that the periorbital signal is associated to autonomic responses and it changes significantly upon the onset of instantaneous stress. The present method enables accurate and consistent extraction of this signal. It aims to replace the heuristic segmentation approach that has been used in stress quantification thus far. Applications in computational psychology and particularly in deception detection are the first to benefit from this new technology. We tested the method on thermal videos of 39 subjects who faced stressful interrogation for a mock crime. The results show that the proposed approach has improved the deception classification success rate to 82%, which is 20% higher compared to the previous approach.

Department of Defense Polygraph Institute, 7540 Pickens Ave., Fort Jackson, SC, 29207, USA.

Ann Biomed Eng. 2006 Jul;34(7):1182-9. Epub 2006 Jun 20.

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.

Pavlidis I, et. al.

Honeywell Laboratories, 3660 Technology Drive, Minneapolis, MN 55418

Nature. 2002 Jan 3;415(6867):35.

We have developed a high-definition thermal-imaging technique that can detect attempted deceit by recording the thermal patterns from people’s faces. This technique has an accuracy comparable to that of polygraph examination by experts and has potential for application in remote and rapid security screening, without the need for skilled staff or physical contact

Ferrarin M, Ludwig N;

Centro di Bioingegneria, Fondazione Don Carlo Gnocchi, IRCCS-Politecnico di Milano, Italy.

Med Biol Eng Comput 2000 Jan;38(1):31-4

Thermal properties of wheelchair cushions have been traditionally studied with thermistor probes, which provide temperature values of limited areas (spot analysis). In this paper, we describe a novel procedure based on thermography for assessing the distribution of temperature over the entire surface of wheelchair cushions. The thermal transient during contact with the body (heating phase) and after use (cooling phase) is considered. The procedure was tested in four different seat cushions (with a gel pad, air-filled cells, gel-filled bubbles and foam-filled bubbles) used by a normal subject. Observed results were compatible with the predicted outcomes based on an analysis of the materials and structures. Specifically: (i) air-filled cushions exhibited the fastest thermal transients, gel cushions the slowest transients, while cushions with a mixed structure exhibited intermediate behaviour; (ii) cushions made from flat surfaces of foam exhibited the highest peak temperatures (30.8 degrees C) as compared to those with air-filled cells (30.35 degrees C) or bubble-shaped surfaces (29.7 degrees C); (iii) the average temperature under the thighs was significantly higher than that under the ischiatic area in all cushions (29.6 degrees C compared with 28.7 degrees C, p < 0.05). It is shown that the present method can be used to differentiate between different cushions. Although the ‘macro-analysis’ inherent in thermography appears to be suited for improving cushion design, this approach should be further investigated to determine its reliability.

Chaerle L, Van Caeneghem W, Messens E, Lambers H, Van Montagu M, Van Der Straeten D;

Laboratorium voor Genetica, Departement Plantengenetica, Vlaams Interuniversitair Instituut voor Biotechnologie, Universiteit Gent, K.L. Ledeganckstraat 35, B-9000 Gent, Belgium.

Nat Biotechnol 1999 Aug;17(8):813-6

Salicylic acid (SA), produced by plants as a signal in defense against induces metabolic heating mediated by alternative respiration in flowers of thermogenic plants, and, when exogenously applied, increases leaf temperature in nonthermogenic plants. We have postulated that the latter phenomenon would be detectable when SA is synthesized locally in plant leaves. Here, resistance to tobacco mosaic virus (TMV) was monitored thermographically before any disease symptoms became visible on tobacco leaves. Spots of elevated temperature that were confined to the place of infection increased in intensity from 8 h before the onset of visible cell death, and remained detectable as a halo around the ongoing necrosis. Salicylic acid accumulates during the prenecrotic phase in TMV-infected tobacco and is known to induce stomatal closure in certain species. We show that the time course of SA accumulation correlates with the evolution of both localized thermal effect and stomatal closure. Since the contribution of leaf respiration is marginal, we concluded that the thermal effect results predominantly from localized, SA-induced stomatal closure. The presymptomatic temperature increase could be of general significance in incompatible plant-pathogen interactions.

Pau HW, Fichelmann J, Wild W;

HNO-Universitatsklinik und Poliklinik Rostock.

Laryngorhinootologie 1998 Dec;77(12):677-81

BACKGROUND: During middle ear surgery manipulations like burring, cooling with water, suction or even screwing cause changes of temperature which should be known to the surgeon. METHOD: An infrared thermovision device was introduced for registration. RESULTS: Thermography is an easy way for continuously recording thermic effects during surgery. If sufficient cooling is guaranteed, no temperatures high enough to cause tissue damage or functional defects could be observed. CONCLUSIONS: Adequate cooling provided, thermal injuries during ear surgery can be neglected. Thermography is an easy method for answering such questions, not only in ear surgery but also in other medical fields.

Sikorski R, Smaga A, Paszkowski T, Walczak R;

 Kliniki Ginekologii II Katedry Poloznictwa i Chorob Kobiecych Wydzialu Lekarskiego AM w Lublinie.

Ginekol Pol 1998 Dec;69(12):1268-72

OBJECTIVES: To evaluate in the standardized conditions the thermal emission by normal uterine cervix and vulva. MATERIALS AND METHODS: Infrared telethermography (ITT) was used to examine vulva and uterine cervix in 32 women aged 24-54 years without colposcopic and cytologic abnormalities. RESULTS: The measured temperatures differed between different topographic points of vulva and uterine vaginal portio. The inter-individual variability of temperatures determined at the same vulvar structures was relatively low. CONCLUSION: The obtained results constitute a basis for further studies on thermovisual definition of therapeutic targets in cases of vulvar and cervical lesions.

Chan LS et al.; 

Department of Earth Sciences, The University of Hong Kong, Hong Kong.

J Travel Med. 2004 Sep-Oct;11(5):273-9.

Following the severe acute respiratory syndrome (SARS) outbreak, remote-sensing infrared thermography (IRT) has been advocated as a possible means of screening for fever in travelers at airports and border crossings, but its applicability has not been established. We therefore set out to evaluate (1) the feasibility of IRT imaging to identify subjects with fever, and (2) the optimal instrumental configuration and validity for such testing. CONCLUSIONS: IRT readings from the side of the face, especially from the ear at 0.5 m, yielded the most reliable, precise and consistent estimates of conventionally determined body temperatures. Our results have important implications for walk-through IRT scanning/screening systems at airports and border crossings, particularly as the point prevalence of fever in such subjects would be very low.