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.

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.

Thyroid diagnosis by thermogram sequence analysis.

Thyroid diagnosis by thermogram sequence analysis.
Chan FH, So AT, Kung AW, Lam FK, Yip HC. Source Department of Electrical and Electronic Engineering, University of Hong Kong, Hong Kong.

Abstract
A computerized thermal imaging system for thyroid diagnosis was developed by the authors and it was discovered that the rate of changes of temperature, rather than the absolute values, associated with a sequence of thermograms could help the medical doctors to identify clinical disorders. In order to further enhance the diagnostic capabilities and speed, a new method for medical thermogram analysis has been developed that compresses a sequence of thermograms into one thermogram while retaining the important information such as the geometrical patterns of the objects and the rate of temperature changes of each pixel within the images. As motion artifacts are unavoidable when a patient undergoes minutes of thermogram recording, direct comparison between images is deemed impossible. A high speed image matching algorithm has been developed to provide an absolute geometrical foundation for pixel-to-pixel comparison. The rate of change of temperature of a particular pixel along the sequence is represented by one single parameter after a process of temperature integration which can then be converted into a corresponding gray level for display. The resultant compressed thermogram can give a clear distinction between problem areas and normal ones. Although our emphasis is on thyroid diagnosis, it is anticipated that this new technique can be applicable to other areas of a human body.

Analysis of thermal properties of wheelchair cushions with thermography.

Analysis of thermal properties of wheelchair cushions with thermography.

Ferrarin M, Ludwig N; Centro di Bioingegneria, Fondazione Don Carlo Gnocchi, IRCCS-Politecnico diMilano, Italy. ferramau@mail.cbi.polimi.it

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 behavior; (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.

Evaluation of provocation test monitoring palmoplantar temperature with the use of thermography for diagnosis of focal tonsillar infection in palmoplantar pustulosis.

Evaluation of provocation test monitoring palmoplantar temperature with the use of thermography for diagnosis of focal tonsillar infection in palmoplantar pustulosis.

Asada H, Miyagawa S, Tamura M, Azukizawa H, Tanemura A, Yamaguchi Y, Sumikawa Y, Itami S, Kubo T,Yoshikawa K.

Source

Department of Dermatology, Nara Medical University, 840 Shijo-cho Kashihara, 634-8522, Nara, Japan. asadah@naramed-u.ac.jp

Abstract

BACKGROUND:

Since focal tonsillar infections are often associated with palmoplantar pustulosis (PPP), provocation tests have been performed for preoperative evaluation of tonsillectomy. However, these tests have not been fully established.

OBJECTIVES:

To introduce a more sensitive operative indication for tonsillectomy to the patients with PPP, we have monitored the temperature after provocation tests at palmoplantar sites, as measured by thermography, and we hypothesized that this methodology may lead to a more sensitive marker for tonsillectomy.

METHODS:

Twenty-two PPP patients with/without clinical tonsillitis were included in this study. After mechanical tonsillar massage, using infrared thermography, we have monitored the surface temperature at palmoplantar sites of 22 patients with PPP, five chronic tonsillitis patients without PPP, and four healthy controls, to compare the findings with the skin lesional outcome after tonsillectomy.

RESULTS:

There was a significant relationship between the effects of tonsillectomy and the results of provocation tests assessed by thermography. The sensitivity, specificity, and efficiency of the provocation tests with thermography of detecting a favorable outcome of tonsillectomy were 75.0, 83.3, and 77.3%, respectively, while those of the provocation tests as estimated with the conventional criteria were 37.5, 83.3, and 50.0%, respectively.

CONCLUSION:

Our results suggest that a new indicator using non-invasive thermography for the provocation tests is useful in predicting the effects of tonsillectomy for PPP.