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1

Image processing techniques for roi identification in rheumatoid arthritis patients from thermal images

Wasilewska A., Pauk J., Ihnatouski M.

Acta Mechanica et Automatica

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2018

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Vol. 12, no. 1

49--53

EN

Rheumatoid arthritis (RA) is a systemic autoimmune disease that manifests itself by joint inflammation, swelling, pain, tenderness and may involve extra-articular organs in severe cases. Joint inflammatory lesions are associated with higher temperature due to increased vascularity in the area of inflamed tissues. This papers aimed to identify heat patterns from ROIs to interpret the presence of inflammation in rheumatoid arthritis patients. The thermovisual image sequences were collected from 65 patients with Rheumatoid Arthritis (RA). Infrared images were generated by a thermal scanning camera (FLIR E60bx Systems Inc., USA). Separate recordings of left and right foot temperature changes were performed for 3 minute periods. The temperature measurement was performed at the moment right after cold water immersion (post-cooling temperature) and at the moment after thermal recovery (post-recovery temperature). The recording of 3-minute foot thermal recovery was used for analysis. Automatically identified ROI corresponds to the area of the soft tissues covering cuboid and navicular bone.

2

An application of a dynamic thermography for studying a relation between thermal and mechanical activities of a skeletal muscle during a static load

Radomski D., Kruszewski K.

Measurement Automation Monitoring

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2017

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Vol. 63, No. 4

139--142

EN

A thermal distribution provides useful information of physiological and pathological processes. However, only a static thermography was applied in the most of medical studies. This paper shows an example of application of a dynamic thermography to study a physiological activity of a skeletal muscle. The goal of the presented work was to study a putative relationship between mechanical and thermal activity of the quadriceps during a static submaximal load. During a strain a dynamic temperature distribution on a thigh surface and a force moment of a knee erector were registered. The performed analysis used a time-dependent mean temperature, a time-dependent standard deviation and an impulse of a force moment. Moreover, we analyzed of autocorrelation functions to compare the dynamics of these parameters. Finally, we showed the nonlinear, statistically significant relationship between spatial-temporal variability of temperature and the force developing by a concentrative contracted quadriceps. A possible biological interpretation of the identified relation is also proposed taking the described mathematical model of muscle heat transfer into account.

3

A new diagnostic IR-thermal imaging method for evaluation of cardiosurgery procedures

Kaczmarek M.

Biocybernetics and Biomedical Engineering

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2016

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Vol. 36, no. 2

344--354

EN

Two methods for monitoring the state of the myocardium during cardiosurgical interventions based on thermal IR imaging are presented below. These methods, called static thermography and active dynamic thermography (ADT), use information about the distribution of temperature on the surface, and an external excitation source to induce thermal transient processes in a tested object. Recording the time series of thermograms allows calculating parametric images – the distribution of the thermal time constant on the visible surface of the myocardium – correlated with the physiological state of the tested tissues. The temperature allows monitoring of vascularization in each phase of cardiosurgical interventions. This is a perfect method for the evaluation of the quality of the inserted graft, as well as the efficiency of cardioplegia, and the quality of many surgical procedures in clinical practice. Such monitoring is prompt, easy and objective, especially if dynamic processes are investigated. During LAD occlusion, the ADT procedure was applied using a cooling external excitation source. In summary, the calculated time constant images provide data of the tested structure and functional information of myocardium infarct. This allows tracking changes in the blood flow in the myocardium and enables the inspection of the quality of the intervention during cardiosurgical procedures.

4

Evaluation of allergic response using dynamic thermography

Rokita E., Rok T., Tatoń G.

Opto-Electronics Review

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2015

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Vol. 23, No. 1

53-59

EN

Skin dynamic termography supplemented by a mathematical model is presented as an objective and sensitive indicator of the skin prick test result. Termographic measurements were performed simultaneously with routine skin prick tests. The IR images were acquired every 70 s up to 910 s after skin prick. In the model histamine is treated as the principal mediator of the allergic reaction. Histamine produces vasolidation and the engorged vessels are responsible for an increase in skin temperature. The model parameters were determined by fitting the analytical solutions to the spatio-temporal distributions of the differences between measured and baseline temperatures. The model reproduces experimental data very well (coefficient of determination = 0.805÷0.995). The method offers a set of parameters to describe separately skin allergic reaction and skin reactivity. The release of histamine after allergen injection is the best indicator of allergic response. The diagnostic parameter better correlates with the standard evaluation of a skin prick test (correlation coefficient = 0.98) than the result of the thermographic planimetric method based on temperature and heated area determination (0.81). The high sensitivity of the method allows for determination of the allergic response in patients with the reduced skin reactivity.

5

Wykorzystanie metod dynamicznej termografii w podczerwieni w badaniach nieniszczących

Różański L., Chajda J., Trafarski A., Ziopaja K.

Zeszyty Naukowe. Elektryka / Politechnika Opolska

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2008

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Vol. 323, z. 60

199-200

EN

The possibility of detection the hidden defects or damage applying the methods of dynamic infrared thermography and the 2D discrete wavelet transform of data measured in thermal processes has been described. Besides of theoretical information about application of these transforms results of MES digital simulations as well as qualitative experimental has been presents.

6

Data visualization in dynamic thermography

Rumiński J., Kaczmarek M., Nowakowski A., Hryciuk M.

Journal of Medical Informatics & Technologies

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2000

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Vol. 1

IT 29--36

EN

Dynamic thermography is proposed as a measurement technique for medical applications. Based on the pulsed thermography different data processing and visualisation algorithms are presented. A new model-based method of data analysis for quantitative evaluation is introduced. Results of a phantom studies are presented.

7

Pomiar przewodności cieplnej i ciepła właściwego materiałów biologicznych

Hryciuk M.

Acta Bio-Optica et Informatica Medica. Inżynieria Biomedyczna

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2000

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Vol. 6, nr 3-4

81-86

PL

W pracy przedstawiono metodę pomiaru przewodności i efuzyjności cieplnej materiałów w zastosowaniu do badań tkanek biologicznych in vitro. Dzięki prostym operacjom matematycznym metoda ta umożliwia także określenie ciepła właściwego badanego materiału i jego dyfuzyjności cieplnej. Zaprezentowano projekt miernika działającego na podstawie tej metody oraz wyniki pomiarów i ich interpretację fizyczną.

EN

The article presents a method of materials thermal conductivity and effusivity measurement applied to research on thermal properties of biological tissues in vitro. Indirectly, the specific heat and thermal diffusivity of the examined material may be evaluated, as well as the project of measurement unit based on the described method is presented, supplemented by the results of biomaterials measurements and their interpretation.