If you use either IEC 60601-2-37 or IEC 62359, the new IEC/TR 62799 2013 Edition was written for you! This Technical Report provides additional information regarding the serious issue of tissue heating produced by diagnostic ultrasound. In order to protect patients, this type of equipment must calculate what’s called the thermal index (TI) and display it on the console for the operator of the device to monitor.
Over time, industry experts have discovered that there are some limitations in how this calculation is made. In fact, the research upon which the calculations of both IEC 62359 and IEC 60601-2-37 are made was actually done by NEMA (the National Electrical Manufacturers Association) and AIUM (the American Institute of Ultrasound in Medicine) back in 1992. That work is defined in the Output Display Standard.
So the 140-page IEC/TR 62799 was developed to examine the various means of quantifying the potential for tissue heating and consequent damage and to suggest approaches for improving diagnostic ultrasound safety.
The committee expects this report to be used for further development of the IEC 62359 document of course. But they also suggest that it will be of value to manufacturers of medical device equipment to improve risk assessment. And they also suggest that health care regulatory authorities, test labs, and so on review it as well.
The report first reviews the current TI situation. Then it covers four ways to improve the current calculations and display in depth. Each solution is reviewed for theory, illustrative results of the display, advantages and disadvantages. And there is great information comparing the 4 approaches which will be of practical assistance to the user.
In the end, the committee does recommend the use of a new index — they call it the TETI, Thermally Equivalent Time Index. It is an easily understood number and one that they feel is more accurate as well. And they recommend that the other additional types of indices continue to be researched: TT (Time to Threshold), SUT (Safe Use Time), and TETD (Thermally Equivalent Time Display.)
Since this is a new publication, you may not be aware of it yet. But here at Document Center we feel that our customers need more information on standards than just notifications when documents they currently own are updated. This blog is to help spread the word and provide insight into the direction of technical considerations that impact the products that our customers design, manufacture, and sell.
You can purchase the IEC/TR 62799 and all IEC standards from Document Center at our web store, www.document-center.com. They are available for delivery in paper format or as pdf downloads. And if you prefer, you are always welcome to contact us by phone (650-591-7600), fax (650-591-7617) or email (info@document-center.com). Remember, Document Center is an authorized resource for the standards you need. We’re your Standards Experts and we’re here to help you!
