Background: Motor imagery is the mental representation of an action without overt movement or muscle activation. However, few previous studies have demonstrated motor imagery training effects as an objective assessment tool in patients with early stroke. Objective: To investigate the effect of motor imagery training on Somatosensory Evoked Potentials (SSEP) and upper limb function of stroke patients. Design: A quasi-experimental study. Methods: Twenty-four patients with stroke were enrolled in this study. All subjects were assigned to the experimental or control group. All participants received traditional occupational therapy for 30 minutes, 5 times a week. The experimental group performed an additional task of motor imagery training (MIT) 20 minutes per day, 5 days a week, for 4 weeks. Both groups were assessed using the SSEP amplitude, Fugl-Meyer assessment of upper extremity (FMA UE) and Wolf motor function test. Results: After the intervention, the experimental group showed significant improvement in SSEP amplitude and FMA UE than did the control group. Conclusion: These findings suggest that the MIT effectively improve the SSEP and upper limb function of stroke patients.

The objective of measurement of bio-signals in measurement uncertainty is not to determine the true value as closely as possible, but to determine a measured value and to assign the interval of the value. The measurement uncertainty is estimated by type A and B evaluations, depending on whether they are evaluated by statistics or the mathematical probability theory. Intraoperative neurophysiologic monitoring is used often for early detection of inherent risk relevant to neurosurgical procedures leading to permanent neurological injury, while it is still potentially reversible. In this study, we evaluated the uncertainties in somatosensory evoked potentials (SSEPs), which are used for monitoring sensory neural pathways. In a 45-year-old man who underwent cervical laminectomy, SSEPs were monitored using the ISIS IOM SYSTEM (Inomed, Emendingen, Germany) to evaluate the uncertainties. Expanded uncertainty were 0.88 mV and 1.22 ms, for amplitude and latency, respectively. Measured values and corresponding uncertainties of amplitude and latency were 2.78 ± 0.88 mV and 24.02 ± 1.22 ms, respectively. The expanded uncertainty (0.88 mV) of the amplitude was approximately 30% of the mean value (2.78 mV). A reasonable explanation for this would be the effects of variables such as electromagnetic waves (diathermy and warming blankets), temperature, blood pressure, sex and body mass index on SSEPs. Careful attention is required in interpreting SSEPs.