Arm resistance

Electrical impedance myography (EIM) is a new method for assessing nerve and muscle problems that Seward Rutkove has been developing for the past 8 years at BIDMC. In this technique, a weak electrical current is passed through the skin and the muscle evaluated completely painlessly. Working with a team of engineers at MIT headed by Joel Dawson, PhD, Seward has created a first-ever handheld EIM device for rapid, clinical use (see photo). It is still very much in a “beta-version”state, but he is testing healthy subjects and people with various nerve injuries to help further refine it.

Here are the data that Seward and his research assistant, Michelle Fogerson, obtained on me a couple of weeks ago. I had an inflammatory nerve problem about 2 years ago that occurred after I had a flu shot that ended up causing problems mostly with my radial nerve (they call it brachial neuritis). Seward and Michelle studied a couple of muscles on both my arms, including one that was affected (my left finger extensor muscles). You can see how different the electrical impedance pattern is in my affected muscle as compared to the opposite side, but how similar the two other muscles were that weren’t affected (the wrist flexor muscles).

Seward is continuing to work on this exciting technique that he hopes will one day make it less necessary to perform needle electromyography, or EMG. (Those who have gone through that procedure will know what I mean when I say that it is one test that is worth avoiding.) If you have questions, you should email him at srutkove (at) bidmc (dot) harvard (dot) edu. (By the way, he is an MD in our Neurology Department.)