Development Of Small Ultrasound Hyperthermia And Chemotherapy Instrument Based On Embedded Principle

Hyperthermia is an effective cancer treatment beside of surgerychemotherapy and radiotherapy. Because hyperthermia can be used togetherwith chemotherapy and radiotherapy as a more effective treatment,hyperthermia conform the idea that use more than one therapy in cancertreatment. With the development of technology in recent years, hyperthermiahas become an important field in tumor therapy. There are two ways inhyperthermia sorted by treatment temperature. HIFU(High Intensity FocusedUltrasound) is a representatives of high temperature therapy. It uses hightemperature（above45℃） in a short time to kill the cancer cells directly. Theother therapy lasts a long time and several times in middletemperature(42-44℃) to induce apoptosis of cancer cells. It also makes use ofthe different response between normal tissue and tumor tissue.This thesis describes a tumor hyperthermia device which uses ultrasoundas the heat source and is based on embedded principle. The device used heattemperature which is got in several ways to control the heat temperature aboutthe temperature which is sat by the doctor with negative feedback regulation.The device uses embedded system as its intelligent control centre to make thedevice small and easy to carry.The hardware of ultrasound hyperthermia and chemotherapy instrumentcan be divided into five parts. They are embedded system, signal generatorand power amplifier, control unit, temperature detection, water-cooling cycle.The embedded system is the centre of the device. Those communicate the device and doctor, control the device, and calculate the temperature and getthe control parameter are all done by the embedded system. The signalgenerator and power amplifier part is in charge of signal producing and poweramplifier, which drives the transducer. The control unit contains a microcontrol chip and its support electric circuit. It communicates with theembedded system to get the control instructions and execute the instructions.Temperature detection contains thermocouple temperature probe and A/Dtransformer. It detects temperature of the monitoring points. The temperatureis delivered to embedded system as the data source of system control. Thewater-cooling cycle contains a constant flow pump, two fans, heat sink andthermoelectric cooler. The water-cooling cycle is used for cooling the waterwhich is used for coupling. This part can prevent the surface skin form scald.The software of ultrasound hyperthermia and chemotherapy instrumentis divided into five parts in accordance with the modular thinking. They arepatients’ database, temperature gathering, temperature adjusting, systemcontrol and communication. The patients’ database records basic informationof the patients and the cure states of every treatment. In future this databasewill link to the PACS. The temperature gathering part gets monitortemperature from several ways such as thermocouple and MRI. Thetemperature adjusting part calculates the output power in a suitable algorithmusing the temperature which is gathered by the temperature gathering part.The system control part transforms various results into control parameters andcontrol commands to control the whole device to work properly. Thecommunication part transports the information between embedded system andcontrol chip using the RS-232serial ports.A small improved ultrasound hyperthermia and chemotherapy instrumenthas been made on the basis of original instrument already. The software of theinstrument has been rewrote and improved. The new software providesinterface functions for linking to PACS and magnetic resonance thermometry.The new software also provides a basis for combining hyperthermia andchemotherapy.