Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 53 for “"blood perfusion"”.
-
A blood-perfusion flowmeter
A variety of methods have been used for measuring blood flow in large vessels. However, almost all of these methods are unsuitable for measuring perfusion flow in tissue. Basically all attempts at perfusion flow measurement have used either a tracer method (radio-active dyes, microspheres) or a …
-
Method for Evaluating Changing Blood Perfusion
… provides insight into methods for estimating blood perfusion, emphasizing the need for accurate modeling in dynamic physiological environments. The thesis critically examines conventional error function solutions used in steady state or gradually changing blood flow scenarios, revealing their …
-
Development of a Phantom Tissue for Blood Perfusion Measurements and Noninvasive Blood Perfusion Estimation in Living Tissue
… method for testing and calibrating surface perfusion sensors has been developed. A phantom tissue model is used to mimic the non-directional blood flow of tissue perfusion. A computational fluid dynamics (CFD) model was constructed in Fluent to design the phantom tissue and validate the …
-
Validation of a Noninvasive Blood Perfusion Measurement Sensor
… of a system to noninvasively estimate blood perfusion using thermal methods. A combination thermocouple/thermopile sensor records heat flux and temperature measurements on the tissue of interest (in this case skin) for a given period of time. These data, in combination with other …
-
A laser based, non-invasive measurement of blood perfusion
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1991.
-
Development of Methodologies for the Noninvasive Estimation of Blood Perfusion
… of a system to noninvasively estimate blood perfusion using thermal methods. This is accomplished by the combination of a bioprobe, biothermal model, and parameter estimation techniques. The probe consists of a heat flux sensor and surface thermocouple placed in contact with tissue …
-
Development of the Passive Perfusion Probe for Non-Invasive Blood Perfusion Measurement
A non-invasive blood perfusion system has been developed and tested in a phantom tissue and an animal model. The system uses a small sensor with a laminated flat thermocouple to measure the heat transfer response to an arbitrary thermal event (convective or conductive) imposed on the tissue …
-
Measurements of thermal properties and blood perfusion using the heat flux microsensor
… was used to demonstrate the effect of tissue blood perfusion on the surface heat flux. Experimental tests were performed on live dogs. Both the numerical model and the experiments showed that increases in blood perfusion could be detected from the transient heat flux measurements. In both …
-
Thermal methods for blood perfusion measurement: application for differential diagnosis of breast cancer.
Massachusetts Institute of Technology. Dept. of Mechanical Engineering. Thesis. 1974. Sc.D.
-
Assessment of the Measurement Repeatability and Sensitivity of a Noninvasive Blood Perfusion Measuring Probe
Blood perfusion is the local, non-directional blood flow through tissue. It is measured as the volumetric flow rate of blood through a given volume of tissue. One method that has been developed for measuring blood perfusion is a probe that measures the temperature response of the tissue when a …
-
Non-invasive objective assessment of diabetic foot ulcer healing with blood perfusion and tissue oxygenation
… researches have examined the correlation between blood flow and tissue oxygenation in diabetic wounds. This thesis is a pioneering work that aims to develop a reliable diagnostic tool to address the tremendous need for coordinated and efficient DFU management via prediction of relative blood …
-
Computational and Experimental Modeling of the Bioheat Transfer Process of Perfusion in Tissue Applied to Burn Wounds
… and heat flux measurements to estimate blood perfusion and thermal resistance in living tissue. Dynamic thermal measurements collected at the surface of the sensor before and after imposing a dynamic thermal cooling event are used with the model to estimate the blood perfusion, thermal …
-
Reflectance photoplethysmography for non-invasive monitoring of tissue perfusion
Monitoring blood perfusion and oxygenation changes is of vital importance and for this reason many different techniques have been developed over the decades. Photoplethysmography (PPG) is an optical technique that measures blood volume variations in vascular tissue and it is well known for its …
-
Parameter estimation in reconstructing temperature fields during hyperthermia.
… is implemented and modified to predict the blood perfusions and thus the complete steady-state temperature fields based on input from a limited number of temperature measurements taken during simulated hyperthermia treatments. Several fundamental phenomena related to this inverse problem are …
-
Laparoskopische Lebendspender-Nephrektomie und Autotransplantation nach perivaskulär injiziertem Papaverin - Experimentelle Studie am Schwein
… study is to evaluate whether renal function and blood perfusion can be enhanced by periarterial application of papaverine during laparoscopic donor nephrectomy in pigs. The study is subdivided in two parts. In part one, intraoperative urine output and creatinine-clearance are measured to …
-
Nanoparticle preconditioning for enhanced thermal therapies in cancer.
… resulting in a dramatic reduction in tumor blood perfusion. In this work, we used an in vivo model system of cryosurgery of human prostate cancer (LNCaP Pro 5) grown in nude male mice. We show that 4 hour pre-treatment with our nanoparticle system leads to a dramatic reduction in tumor blood …
-
Thermal-based probe for testing endothelial dysfunction and possible implications for diagnosing atherosclerosis
… A thermal-based approach using temperature and blood perfusion measurements in conjunction with an arterial challenge has the potential to quantitatively assess endothelial dysfunction. This report includes a detailed review of previous attempts to characterize endothelial dysfunction and a …
-
Physiological responses of human retina and choroid to retinal image defocus: Implications for myopia
… defocus, and to investigate alterations in blood perfusion as a potential mechanism underlying changes in choroidal thickness in response to retinal image defocus. Methods: Experiment (1): Nineteen healthy young adults (age: 23 ± 3.5 years, spherical equivalent refraction (SER): +0.25 to …
-
Development and Validation of a Brain Phantom for Therapeutic Cooling Devices
… is circulated 37 degree water, representing blood perfusion. The phantom was tested in a series of cooling trials using a fluid-cooled cooling block during which the perfusion rate was varied. Results were compared against a validated finite difference (FD) model. The model was used to …
Page 1 of 3