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The Heat Transfer Rate (HTR) of tissue is a major problem in controlling the brain tissue temperature under laser therapy to remove a tumor. For the planning, Planning, according to research (7), to set HTR of the brain tissue provides the result of the cerebral blood flow (CBF) by applying the tissue residue curves of dynamic susceptibility in contrast to magnetic resonance imaging (DSC-MRI) with gadolinium (Gd). The research created a map of heat transfer for every temperature level for brain tissue CBF by studying the samples of Glioblastoma and Meningioma tissues in the two HTR diagrams. This research, studied five sample patients by using perfusion of multiple lesions diffuse enhancement (n = 1), irregular enhancement (n = 1), and ring enhancement( n = 3). The perfusion rate from CBF of the samples was compared with the database. The result, of the HTR value HTR, at a brain tissue temperature of 34°C to 43 °C had the same result as from the analysis of the tumor; HTR increases around the rim of the tumor while the value inside is low. Another result was the HTR inside the tumor was high, while the HTR at the rim was low. The HTR data could be used to simulate tissue under the equation of bio-heat transfer.

This paper introduces a non-invasive, contrast-enhanced ultrasound (CEUS) infusion method to quantify the health of viable donor livers. The method uses the infusion of microbubbles and their destruction and subsequent replenishment to measure the perfusion rate in the liver microvasculature. The proposed method improves on the previous parameter extraction approaches applied to the flash-replenishment technique by addressing the effects of the microbubble mixing within the perfusate bath and destruction rate. By doing so, the tissue perfusion rate can be extracted from the data even though the microbubble concentration is not constant throughout image acquisition. The measured changes in the tissue perfusion rate showed that CEUS infusion is a viable biomarker for assessing liver health.

This paper presents simulations of controlled hypothermia for the human head in view of improving the hypothermia process. We study the effect of head parameters, such as thickness of each region of the head (scalp, bone, gray matter, and white matter) heat generation rate, and blood perfusion rate, and the Peltier element cooling temperature on the behavior of the overall head cooling through induced controlled hypothermia. Two models are presented: one without heat generation rate and blood perfusion rate and the other—a more advanced model—with both heat generation rate and blood perfusion rate included. The results are described and discussed.

This paper presents development of a microwave system for noninvasive blood perfusion measurement. The proposed system is based on a thermal perfusion measuring method using microwave techniques. In this method, the tissue temperature is raised by microwave heating (900 MHz) to no more than one degree Celsius, and after the discontinuation of the microwave heating signal, the temperature decay measured using microwave radiometric sensing (1-2 GHz) is indicative of the blood perfusion rate. The preliminary results of the system's test are provided.

This paper presents an analysis of heat sink effect in hepatic cancer treatment near arterial vessel for microwave ablation by using finite element method. We analyze the temperature distribution, Specific Absorbtion Rate (SAR) and coagulation area in two models. The first is hepatic tissue without artery and the second is hepatic tissue with artery. In the second model, we specify distance between antenna and artery at 10 mm. The initial condition is set as power at 50 watts, temperature at 37 °C and blood perfusion rate is varied at 6.4 × 10-10, 6.4 × 10-3 and 6.4 × 104 l/s. The simulation results by using three-dimensional finite element analysis show that the temperature distribution in case of hepatic tissue with no artery is larger than the case with artery. We also found that blood perfusion rate affects to the temperature distribution in hepatic tissue. Higher blood perfusion rate, higher heat sink effect occur.

Temperature is a very important factor in laser moxibustion. This paper foucus on temperature field in simulated living-porcine liver tissue radiated by laser. Firstly, we place simulated blood vessels in isolated porcine liver to simulate living liver and obtain simulation temperature field by the finite element analysis; then we use K type thermocouples and thermocouple amplifier respectively measured the temperature field of isolated porcine liver and simulated living liver. The experiment results of the two are basically consistent, in the same position of organization, blood perfusion rate will be significantly lower the temperature. These researches provide the basis for the establishment of laser moxibustion in TCM.

For metabolic diseases, functional changes are often earlier than structural lesions, for example, diabetes. The paper aims to provide a survey using Support Vector Machine (SVM) to predict and assess metabolic functions of diabetes based on bio-heat transfer theory and infrared thermal imaging technology. Two metabolic characteristic values, metabolic function parameter and blood perfusion rate, are extracted from thermography data of cold water stimulation experiment as inputs of SVM to set up models by different kernel functions. For more than 2000 clinical data used in the paper, the prediction accuracy averaged 90%. The research provides a new attempt to evaluate diabetes metabolic function, hoping for contribution to early detection of diabetes.

For sequential perfusion measurements in several image planes with replenishment method, we propose a fast technique by consecutively scanning respective image planes twice: Firstly using only a short period of imaging pulses after micro- bubble destruction to assess slope and secondly using few imaging pulses to assess final value. Both scans are combined to extract perfusion rate and blood volume.

A simple procedure based on the introduction of characteristic times of involving heat transfer processes and geometrical dimensions of the problem is proposed to analytically study light and heat propagation through multicomponent biological tissues irradiated by an external light pulse. The procedure enables one to explicitly analyze the effects of all optical and thermal parameters of the problem. The proposed model of the parameters is discussed and critically compared with published data. The simulations can be easily generalized to include multilayered tissue structure and blood perfusion rate into consideration. Sample examples are given to illustrate spatial and temporal temperature distributions over tissue depth.

Thirty dogs were heated with interstitial RF hyperthermia through four pairs of electrodes placed in the rear leg muscle, 6 cm distal to the femoral head. During one hour of 43 degrees C treatment, perfusion rates increased from the control value of 10 ml/min/100 gm to 39 ml/min/100 gm after 8 minutes of treatment. This initial increase in perfusion, most likely a reactive hyeremia due to the interstitial treatment, decreased back to the control level within minutes. This first peak was followed by a second peak at 40 min of treatment. This second peak reached 46 ml/min/100 gm. Following treatment, perfusion rates were measured in tissue at various times over the next week. At 4 hours following treatment, blood flow dropped to 17 ml/min/100 gm. The blood flow continued to drop over the next 48 hours, reaching 12 ml/min/100 gm. By the end of the week, the blood flow had returned to an average of 19 ml/min/100 gm. >