27-02-2015, 01:04 PM
I would like to get ppt on Treating Cardiac Disease With Catheter-Based Tissue Heating
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catheter based tissue heating system ppt
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I would like to get ppt on Treating Cardiac Disease With Catheter-Based Tissue Heating
28-03-2017, 02:34 PM
In microwave ablation, electromagnetic energy would be delivered through a catheter to a precise location in a coronary artery for the selective heating of a directed atherosclerotic lesion. Advantageous temperature profiles would be obtained by controlling the power supplied, pulse duration and frequency. The main components of a microwave ablation apparatus would include a microwave source, a catheter / transmission line and an antenna at the distal end of the catheter. The antenna would focus the radiated beam so that most of the microwave energy would be deposited within the directed atherosclerotic lesion. Due to the rapid decay of the electromagnetic wave, little energy would pass towards, or beyond, the adventitia. By appropriate choice of power supplied, pulse duration, frequency and antenna design (which affects the width of the irradiated beam), the temperature profile could be adapted to the size, shape and type of lesion being trying.
For decades, scientists have been using electromagnetic and sonic energy to serve medicine. But apart from electro surgery, his efforts have focused on the diagnostic imaging of internal structures of the body, particularly in the case of X-rays, MRI and ultrasound systems. Lately, however, researchers have begun to see acoustic and electromagnetic waves in a completely new light, turning their attention to therapeutic applications rather than diagnostic applications. Current research is exploiting the ability of radiofrequency (RF) and microwaves to generate heat, essentially by exciting molecules. This heat is used predominantly to release the cells. Of the two technologies, RF was the first to be used in a marketable device. And now microwave devices are entering the marketing stage. These technologies have different strengths weaknesses that will define their use and determine their market niches. The depth at which microwaves can penetrate tissues is primarily a function of the dielectric properties of tissues and the frequency of microwaves.
The tissue of the human body is enormously varied and complex, with innumerable types of structures, components and cells. These tissues vary not only in an individual, but also among people of different sex, age, physical condition, health and even depending on external factors, such as food eaten, air breathed, room temperature, or even the state of spirit . From the point of view of RF and microwave in the frequency range 10 MHz ~ 10GHz, however, biological tissue can be seen macroscopically in terms of its mass and electromagnetic characteristics: dielectric constant and electrical conductivity. These are frequency dependent and highly dependent on the particular tissue type.
All biological tissue is electrically conductive, absorbing microwave energy and converting it to heat as it penetrates the tissue. Delivering heat in depth is not only valuable for cooking dinner, but can also be very useful for many therapeutic medical applications. These include: diathermy for mild orthopedic heating, death of hyperthermia cells for cancer therapy, microwave ablation, and microwave assisted balloon angioplasty. These last two are the subject of this article. It should also be mentioned that based on the long history of exposure to high microwave power in humans, it is reasonable that, except for the effects of overheating, microwave radiation is medically safe. No credible, carcinogenic, muragenic, or poisonous effects have been reported from microwave exposure.
For decades, scientists have been using electromagnetic and sonic energy to serve medicine. But apart from electro surgery, his efforts have focused on the diagnostic imaging of internal structures of the body, particularly in the case of X-rays, MRI and ultrasound systems. Lately, however, researchers have begun to see acoustic and electromagnetic waves in a completely new light, turning their attention to therapeutic applications rather than diagnostic applications. Current research is exploiting the ability of radiofrequency (RF) and microwaves to generate heat, essentially by exciting molecules. This heat is used predominantly to release the cells. Of the two technologies, RF was the first to be used in a marketable device. And now microwave devices are entering the marketing stage. These technologies have different strengths weaknesses that will define their use and determine their market niches. The depth at which microwaves can penetrate tissues is primarily a function of the dielectric properties of tissues and the frequency of microwaves.
The tissue of the human body is enormously varied and complex, with innumerable types of structures, components and cells. These tissues vary not only in an individual, but also among people of different sex, age, physical condition, health and even depending on external factors, such as food eaten, air breathed, room temperature, or even the state of spirit . From the point of view of RF and microwave in the frequency range 10 MHz ~ 10GHz, however, biological tissue can be seen macroscopically in terms of its mass and electromagnetic characteristics: dielectric constant and electrical conductivity. These are frequency dependent and highly dependent on the particular tissue type.
All biological tissue is electrically conductive, absorbing microwave energy and converting it to heat as it penetrates the tissue. Delivering heat in depth is not only valuable for cooking dinner, but can also be very useful for many therapeutic medical applications. These include: diathermy for mild orthopedic heating, death of hyperthermia cells for cancer therapy, microwave ablation, and microwave assisted balloon angioplasty. These last two are the subject of this article. It should also be mentioned that based on the long history of exposure to high microwave power in humans, it is reasonable that, except for the effects of overheating, microwave radiation is medically safe. No credible, carcinogenic, muragenic, or poisonous effects have been reported from microwave exposure.
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