Intraoperative monitoring with motor evoked potentials (MEPs) is a direct motor tract monitoring technique which is now the most important monitoring tool for spinal cord surgery [8,9]. Motor potentials are evoked with tran-scranial electrical stimulation of the motor cortex in two ways: a single-stimulus technique and a multipulse technique (Fig. 29.10). With a single stimulus, a single volley of signals in fast conducting corticospinal axons is generated, which is then recorded with an electrode placed on the spinal cord, usually in the epidural space. This signal is called a D-wave, because it results from Direct activation of these fast-conducting axons. The D-wave's amplitude is a relative measure of the number of fast-conducting cor-ticospinal fibers (Fig. 29.11). The multipulse or train stimulus technique [21] evokes a muscle response in target muscles (thenar, anterior

Cure Your Yeast Infection For Good

Cure Your Yeast Infection For Good

The term vaginitis is one that is applied to any inflammation or infection of the vagina, and there are many different conditions that are categorized together under this ‘broad’ heading, including bacterial vaginosis, trichomoniasis and non-infectious vaginitis.

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