Hatice Tankisi, David Burke, Liying Cui, Mamedede Carvalhod, Satoshi Kuwabara, Sanjeev D. Nandedkar,
Seward Rutkove, Erik Stålberg, Michel J.A.M.van Putten, Anders Fuglsang-Frederiksen
The signal is loud and clear. Standardization is becoming more important in the health care system, with rapidly improving new technology enabling greater standardization of instrumentation. Most EMG equipment is now digital, and computer-based EMG machines are now highly sophisticated, serving not only the performance of tests but also report generation and data storage. To obtain optimal return on the investment in a new machine, the clinical neurophysiologist must understand its workings, be fully aware of the effects of different electrodes and different stimulus and recording parameters and be able to personalize the computer programs. The most important aspects of EMG features and technology includes:
Instrumentation: EMG machines have a dedicated hardware unit with amplifiers, stimulators, control panel and a separate computer. This configuration allows the computer to be upgraded or replaced, while keeping the EMG hardware unit. In the EMG hardware, the amplifiers and stimulators are the most important parts.
EMG hardware and software: Digital signal processing and amplifiers with optimal signal to noise ratio. The software is responsible for signal processing and for generating reports. Databases can be created and remote review used for second opinions or to help with interpretation. Constant changes in operating systems and in regulations governing patient information protection can make this a challenging task.
Storage and delay: All current commercially available EMG machines have the functions of temporary storage and trigger and delay lines. The latter allows the isolation of a single action potential from other action potentials and so enables analysis and confirmation of the consistency of the shape. By delaying each action potential after it has triggered the sweep, it appears in the same position on the screen every time there is a discharge of that unit.
This article presents an in depth discussion of EMG instrumentation including amplifiers and filters, digital signal analysis and settings utilization for the optimization of EMG recordings.
Access the complete article
Download to read the complete article on Standards of Instrumentation of EMG today.