STANDARDISATION OF SHOCK WAVE LITHOTRIPTERS

摘要

There is an urgent requirement to develop global standards for the calibration of biomedical equipment, for better healthcare, as per WTO (World Trade Organisation) norms. National Physical Laboratory of India is actively involved in the development, maintenance and establishment of primary standards for the country, for both electrical and non-electrical parameters. It is planned to extend the facility for maintaining and developing the standards for the calibration of biomedical equipment, devices and systems. The ultrasonic lithotripters are in common use, these days, in the hospitals, for the removal of the stones present in the kidney or gall bladder, without surgery. It is, however, lacking to standardise the dosage level and duration, for a particular treatment. Due to the high intense shock-waves generated by the lithotripters, namely ESWL (Extracorporeal Shock Wave Lithotripters), there are side effects on the soft biological tissues in the human body. Even the delicate nerves and fibres in the surrounding of the kidney or the gall bladder, are damaged. It is, therefore, important to standardise the output parameters of the lithotripters, from time to time, preferably on site. In order to have the facility for calibration of such high power lithotripters, a new smart portable acoustic power dosimeter is developed for the measurement of power output of the lithotripters. The design and development of this smart sensor is given in the present paper. Other techniques for the optimisation of the performance of the lithotripters are also discussed, in brief. The establishment of the new facility for the standardisation and calibration of shock wave lithotripters will assist in the better treatment of the patients suffering with the presence of stones in the kidney or gall-bladder. Additionally, it will help in maintaining proper safety for the patient as well as the doctors or operators of the machine.