Infrared thermography: Experience from a decade of pediatric imaging.
Saxena AK, Willital GH. Department of Pediatric Surgery, Medical University of Graz, Auenbruggerplatz 34, Graz, A-8036, Austria
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 re implantation, burns as well as skin and vascular
growth after bio-material 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.
Wednesday, June 8, 2016
Tuesday, June 7, 2016
Thermal signature analysis as a novel method for evaluating inflammatory arthritis activity.
Thermal signature analysis as a novel method for evaluating inflammatory arthritis activity.
Brenner M, Braun C, Oster M, Gulko PS. North Shore-LIJ Research Institute, United States.
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 mono-articular model of inflammatory arthritis of the ankle induced with an intraarticular (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.
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 mono-arthritis 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.
Brenner M, Braun C, Oster M, Gulko PS. North Shore-LIJ Research Institute, United States.
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 mono-articular model of inflammatory arthritis of the ankle induced with an intraarticular (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.
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 mono-arthritis 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.
Monday, June 6, 2016
Timing of the thermographic assessment of burns.
Timing of the thermographic assessment of burns.
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.
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.
Friday, June 3, 2016
Contemporary applications of infrared imaging in medical diagnostics.
Contemporary applications of infrared imaging in medical diagnostics.
Mikulska D. Katedra i Klinika Chorób Skórnych i Wenerycznych Pomorskiej Akademii Medycznej al. Powstanców Wlkp. 72, 70-111 Szczecin.
INTRODUCTION: Thermal imaging is a non-contact, non-invasive diagnostic method for study human body temperature. Therefore infrared thermal imaging finds increasing application in clinical medicine.
PURPOSE: The aim of this paper was to present and discuss the history and applications of thermal imaging in medicine.
MATERIAL AND METHODS: The literature dealing with the history and applications of thermal imaging in medicine has been reviewed.
RESULTS: Medical thermography was born in 1957 when a surgeon, Dr. R. Lawson discovered that his breast cancer patients had higher skin temperature over the cancer area. Since the 1970's thermography has been used in many areas of medicine. Early problems such as low detector sensitivity, but most significantly, poor training of thermography technicians was the source of error in thermography and retarded the acceptance of this technique until 1990. Since that time, thermographic equipment has evolved significantly. Modern thermal imaging systems comprise
technically advanced thermal cameras coupled to computers with sophisticated software solutions. The recorded images are now of good quality and may be further processed to obtain reliable information. Thermography can be applied as a diagnostic tool in oncology, allergic diseases, angiology, plastic surgery, rheumatology, and elsewhere. Contemporary thermal imaging must be performed according to certain principles aimed at reliability and reproducibility of results.
CONCLUSIONS: 1. Thermography is a safe, accurate and, most importantly, a noninvasive diagnostic method in clinical medicine. 2. Ignoring any of the principles worked out by the European Association of Thermology leaves thermography open to error and thus reduces acceptance of this technique in medical diagnostics.
Mikulska D. Katedra i Klinika Chorób Skórnych i Wenerycznych Pomorskiej Akademii Medycznej al. Powstanców Wlkp. 72, 70-111 Szczecin.
INTRODUCTION: Thermal imaging is a non-contact, non-invasive diagnostic method for study human body temperature. Therefore infrared thermal imaging finds increasing application in clinical medicine.
PURPOSE: The aim of this paper was to present and discuss the history and applications of thermal imaging in medicine.
MATERIAL AND METHODS: The literature dealing with the history and applications of thermal imaging in medicine has been reviewed.
RESULTS: Medical thermography was born in 1957 when a surgeon, Dr. R. Lawson discovered that his breast cancer patients had higher skin temperature over the cancer area. Since the 1970's thermography has been used in many areas of medicine. Early problems such as low detector sensitivity, but most significantly, poor training of thermography technicians was the source of error in thermography and retarded the acceptance of this technique until 1990. Since that time, thermographic equipment has evolved significantly. Modern thermal imaging systems comprise
technically advanced thermal cameras coupled to computers with sophisticated software solutions. The recorded images are now of good quality and may be further processed to obtain reliable information. Thermography can be applied as a diagnostic tool in oncology, allergic diseases, angiology, plastic surgery, rheumatology, and elsewhere. Contemporary thermal imaging must be performed according to certain principles aimed at reliability and reproducibility of results.
CONCLUSIONS: 1. Thermography is a safe, accurate and, most importantly, a noninvasive diagnostic method in clinical medicine. 2. Ignoring any of the principles worked out by the European Association of Thermology leaves thermography open to error and thus reduces acceptance of this technique in medical diagnostics.
Thursday, June 2, 2016
Thermographic assessment of temporomandibular disorders symptomology during orthodontic treatment.
Thermographic assessment of temporomandibular disorders symptomology during orthodontic treatment.
McBeth SB, Gratt BM.
Source
University of California, School of Dentistry, Los Angeles, USA.
Abstract
The relationship between orthodontic treatment and temporomandibular disorder (TMD) symptoms has been the focus of many subjective studies. Objective studies are now needed. Electronic thermography (ET) has shown promise as an objective tool for assessing temporomandibular disorders. Clinical TMD examinations and ET were performed on 21 control subjects, 18 subjects undergoing orthodontic treatment, and 20 subjects with TMD pain. Standardized blinded clinical examinations that used algometry were conducted. Data were analyzed to determine the usefulness of ET as an objective measure of TMD symptoms. The ET alone identified the subjects with painful clicking TMD with a sensitivity of 87%. Subjects with no painful clicking (controls) were identified with a specificity of 86%. The ET findings also had a strong correlation with pain to muscle palpation. This study indicates that ET shows promise as an objective tool for selecting normal subjects from subjects with TMD symptoms. The ET could prove to be valuable in accessing the relationship between orthodontic treatment and TMD symptoms in future longitudinal studies.
McBeth SB, Gratt BM.
Source
University of California, School of Dentistry, Los Angeles, USA.
Abstract
The relationship between orthodontic treatment and temporomandibular disorder (TMD) symptoms has been the focus of many subjective studies. Objective studies are now needed. Electronic thermography (ET) has shown promise as an objective tool for assessing temporomandibular disorders. Clinical TMD examinations and ET were performed on 21 control subjects, 18 subjects undergoing orthodontic treatment, and 20 subjects with TMD pain. Standardized blinded clinical examinations that used algometry were conducted. Data were analyzed to determine the usefulness of ET as an objective measure of TMD symptoms. The ET alone identified the subjects with painful clicking TMD with a sensitivity of 87%. Subjects with no painful clicking (controls) were identified with a specificity of 86%. The ET findings also had a strong correlation with pain to muscle palpation. This study indicates that ET shows promise as an objective tool for selecting normal subjects from subjects with TMD symptoms. The ET could prove to be valuable in accessing the relationship between orthodontic treatment and TMD symptoms in future longitudinal studies.
Wednesday, June 1, 2016
Dynamic infrared imaging of cutaneous melanoma and normal skin in patients treated with BNCT.
Dynamic infrared imaging of cutaneous melanoma and normal skin in patients treated with BNCT.
Santa Cruz GA, Bertotti J, Marín J, González SJ, Gossio S, Alvarez D, Roth BM, Menéndez P, Pereira MD, Albero M, Cubau L, Orellano P, Liberman SJ.
Source
Dpto. de Instrumentación y Control, Comisión Nacional de Energía Atómica, Av. del Libertador 8250 (1429), Buenos Aires, Argentina. santacr@cnea.gov.ar
Abstract
We recently initiated a program aimed to investigate the suitability of dynamic infrared imaging for following-up nodular melanoma patients treated with BNCT. The reason that makes infrared imaging attractive is the fact that it constitutes a functional and non-invasive imaging method, providing information on the normal and abnormal physiologic response of the nervous and vascular systems, as well as the local metabolic rate and inflammatory processes that ultimately appear as differences in the skin temperature. An infrared camera, with a focal plane array of 320 x 240 uncooled ferroelectric detectors is employed, which provides a video stream of the infrared emission in the 7-14 micron wavelength band. A double black-body is used as reference for absolute temperature calibration. After following a protocol for patient preparation and acclimatization, a basal study is performed. Subsequently, the anatomic region of interest is subjected to a provocation test (a cold stimulus), which induces an autonomic vasoconstriction reflex in normal structures, thus enhancing the thermal contrast due to the differences in the vasculature of the different skin regions. Radiation erythema reactions and melanoma nodules possess typically a faster temperature recovery than healthy, non-irradiated skin. However, some other non-pathological structures are also detectable by infrared imaging, (e.g. scars, vessels, arteriovenous anastomoses and injuries), thus requiring a multi-study comparison in order to discriminate the tumor signal. Besides the superficial nodules, which are readily noticeable by infrared imaging, we have detected thermal signals that are coincident with the location of non-palpable nodules, which are observable by CT and ultrasound. Diffuse regions of fast temperature recovery after a cold stimulus were observed between the third and sixth weeks post-BNCT, concurrent with the clinical manifestation of radiation erythema. The location of the erythematous visible and infrared regions is consistent with the 3D dosimetry calculations.
Santa Cruz GA, Bertotti J, Marín J, González SJ, Gossio S, Alvarez D, Roth BM, Menéndez P, Pereira MD, Albero M, Cubau L, Orellano P, Liberman SJ.
Source
Dpto. de Instrumentación y Control, Comisión Nacional de Energía Atómica, Av. del Libertador 8250 (1429), Buenos Aires, Argentina. santacr@cnea.gov.ar
Abstract
We recently initiated a program aimed to investigate the suitability of dynamic infrared imaging for following-up nodular melanoma patients treated with BNCT. The reason that makes infrared imaging attractive is the fact that it constitutes a functional and non-invasive imaging method, providing information on the normal and abnormal physiologic response of the nervous and vascular systems, as well as the local metabolic rate and inflammatory processes that ultimately appear as differences in the skin temperature. An infrared camera, with a focal plane array of 320 x 240 uncooled ferroelectric detectors is employed, which provides a video stream of the infrared emission in the 7-14 micron wavelength band. A double black-body is used as reference for absolute temperature calibration. After following a protocol for patient preparation and acclimatization, a basal study is performed. Subsequently, the anatomic region of interest is subjected to a provocation test (a cold stimulus), which induces an autonomic vasoconstriction reflex in normal structures, thus enhancing the thermal contrast due to the differences in the vasculature of the different skin regions. Radiation erythema reactions and melanoma nodules possess typically a faster temperature recovery than healthy, non-irradiated skin. However, some other non-pathological structures are also detectable by infrared imaging, (e.g. scars, vessels, arteriovenous anastomoses and injuries), thus requiring a multi-study comparison in order to discriminate the tumor signal. Besides the superficial nodules, which are readily noticeable by infrared imaging, we have detected thermal signals that are coincident with the location of non-palpable nodules, which are observable by CT and ultrasound. Diffuse regions of fast temperature recovery after a cold stimulus were observed between the third and sixth weeks post-BNCT, concurrent with the clinical manifestation of radiation erythema. The location of the erythematous visible and infrared regions is consistent with the 3D dosimetry calculations.
Tuesday, May 31, 2016
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Interexaminer reliability of infrared thermography for the diagnosis of complex regional pain syndrome.
Inter-examiner reliability of infrared thermography for the diagnosis of complex regional pain syndrome.
Eunjoo Choi Pyung-Bok Lee Francis Sahngun Nahm Department of Anesthesiology and Pain Medicine, Seoul National University Bundang Hospital, Seongnam, Korea.
Skin Research and Technology (Impact Factor: 1.41). 01/2013; DOI: 10.1111/srt.12032
Source: PubMed
ABSTRACT BACKGROUND/PURPOSE: Infrared thermography (IRT) is a useful tool for assessing skin temperature abnormalities in patients with complex regional pain syndrome (CRPS). Although determining regions of interest (ROIs) is an essential process for interpreting thermographic images, there are no validated and standardized guidelines to determine ROIs. Therefore, ROIs may be determined differently by each observer even for the same IRT images, which can result in an important issue for IRT reliability. The purpose of this study was to investigate the inter-examiner reliability of IRT in patients with CRPS.
METHODS: Infrared thermographic images of 28 patients diagnosed with CRPS were reviewed by three independent examiners. The shapes, sizes, and the detailed locations of the ROIs were determined by the investigator's own opinion based on patient history and symptoms. After maximal skin temperature of the ROI was obtained for each patient, the degree of agreement among the three examiners limbs was assessed.
RESULTS: The intraclass correlation coefficient among the three independent raters was 0.865 (95% confidence interval, 0.748-0.933), indicating a high degree of reliability (P < 0.001).
CONCLUSIONS: The reliability of IRT for assessing skin temperature abnormalities in CRPS was high when the ROIs were determined based on patient history and symptoms.
Eunjoo Choi Pyung-Bok Lee Francis Sahngun Nahm Department of Anesthesiology and Pain Medicine, Seoul National University Bundang Hospital, Seongnam, Korea.
Skin Research and Technology (Impact Factor: 1.41). 01/2013; DOI: 10.1111/srt.12032
Source: PubMed
ABSTRACT BACKGROUND/PURPOSE: Infrared thermography (IRT) is a useful tool for assessing skin temperature abnormalities in patients with complex regional pain syndrome (CRPS). Although determining regions of interest (ROIs) is an essential process for interpreting thermographic images, there are no validated and standardized guidelines to determine ROIs. Therefore, ROIs may be determined differently by each observer even for the same IRT images, which can result in an important issue for IRT reliability. The purpose of this study was to investigate the inter-examiner reliability of IRT in patients with CRPS.
METHODS: Infrared thermographic images of 28 patients diagnosed with CRPS were reviewed by three independent examiners. The shapes, sizes, and the detailed locations of the ROIs were determined by the investigator's own opinion based on patient history and symptoms. After maximal skin temperature of the ROI was obtained for each patient, the degree of agreement among the three examiners limbs was assessed.
RESULTS: The intraclass correlation coefficient among the three independent raters was 0.865 (95% confidence interval, 0.748-0.933), indicating a high degree of reliability (P < 0.001).
CONCLUSIONS: The reliability of IRT for assessing skin temperature abnormalities in CRPS was high when the ROIs were determined based on patient history and symptoms.
Labels:
ABNORMALITIES,
CRPS,
infrared,
IRT,
physiology,
skin,
temperature,
THERMOGRAPHY
Friday, May 20, 2016
Can rotational atherectomy cause thermal tissue damage? A study of the potential heating and thermal tissue effects of a rotational atherectomy device.
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.
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.
Thursday, May 19, 2016
Effectiveness of a noninvasive digital infrared thermal imaging system in the detection of breast cancer.
Effectiveness of a noninvasive digital infrared thermal imaging system in the detection of breast cancer.
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, USA.
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.
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, USA.
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.
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