Quantitative visualization and detection of skin cancer using dynamic thermal imaging.

Quantitative visualization and detection of skin cancer using dynamic thermal imaging.
Herman C1, Cetingul MP.

Abstract
In 2010 approximately 68,720 melanomas will be diagnosed in the US alone, with around 8,650 resulting in death. To date, the only effective treatment for melanoma remains surgical excision, therefore, the key to extended survival is early detection. 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, multi-spectral 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. 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. 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 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, 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. 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.

Application of thermography for non-invasive diagnosis of thyroid gland disease.

Application of thermography for non-invasive diagnosis of thyroid gland disease.
Helmy A1, Holdmann M, Rizkalla M.

Abstract
In this paper, a computer-based prototype device was designed based on an economical noninvasive system that could detect and display the relative skin temperature variations present in human patients suffering from thyroid disorders. Such a system could be used to augment the normal procedures followed by the physician in diagnosing the thyroid to detect areas of hyperactivity within the gland. Because a hyperactive nodule is a center of increased blood flow and chemical activity, it might be also a center of heat production that is detectable by thermal sensing. This paper also presents a finite-element analysis (FEA) of a hot thyroid nodule that is used for investigating the temperature distribution in conjunction with the prototype. The instrumentation model built was based on actual dimensional human model for thyroid nodules obtained from various patients. A software program was written in Visual Basic to detect the temperature distribution around the hot spot. The software also incorporates means to minimize the thermal noise associated with the body temperature. The FEA utilizes the same boundary values used in the practical settings. This includes initial values of temperatures for the hot spot and its surroundings. The results of the finite-element simulation assisted in the selection of the solid state sensors that were used in the instrumentation of the thermographic system. The selected sensors were calibrated for their functionality and dynamic performance according to the specifications. The new noninvasive diagnostic technique was applied to patients having Graves' diseases at the Indiana University (IU) Hospital, and compared with the existing scheme that utilizes I Scan. The results of the new diagnostic method were in good agreement with the current existing method.

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.

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.

Infrared thermography in newborns: the first hour after birth.

Infrared thermography in newborns: the first hour after birth.
Christidis I, Zotter H, Rosegger H, Engele H, Kurz R, Kerbl R. Department of Pediatrics, University of Graz, Austria.
"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