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Journal Article 2012; 33(4): 431-441 PubMed PMID: 22936262 Citation  Keywords:  Adolescent, Adult, Analysis of Variance, Case-Control Studies, Efferent Pathways:physiology, Evoked Potentials, Motor:physiology, Female, Humans, Male, Middle Aged, Motor Cortex:physiology, Muscle, Skeletal:innervation, Neural Inhibition:physiology, Neuro.   

OBJECTIVES AND METHODS: Excitability changes in the primary motor cortex in 17 spinal-cord injured (SCI) patients and 10 controls were studied with paired-pulse transcranial magnetic stimulation. The paired pulses were applied at inter-stimulus intervals (ISI) of 2 ms and 15 ms while motor evoked potentials (MEP) were recorded in the biceps brachii (Bic), the abductor pollicis brevis (APB) and the tibialis anterior (TA) muscles.

RESULTS: The study revealed a significant decrease in cortical motor excitability in the first weeks after SCI concerning the representation of both the affected muscles innervated from spinal segments below the lesion, and the spared muscles rostral to the lesion. In the patients with motor-incomplete injury, but not in those with motor-complete injury, the initial cortical inhibition of affected muscles was temporarily reduced 2-3 months following injury. The degree of inhibition in cortical areas representing the spared muscles was observed to be smaller in patients with no voluntary TA activity compared to patients with some activity remaining in the TA. Surprisingly, motor-cortical inhibition was observed not only at ISI 2 ms but also at ISI 15 ms. The inhibition persisted in patients who returned for a follow-up measurement 2-3 years later.

CONCLUSION: The present data showed different evaluation of cortical excitability between patients with complete and incomplete spinal cord lesion. Our results provide more insight into the pathophysiology of SCI and contribute to the ongoing discussion about the recovery process and therapy of SCI patients....

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Clinical Trial 2005; 26(2): 143-147 PubMed PMID: 15855886 Citation  Keywords:  Adult, Cerebral Cortex:physiology, Diabetes Complications:physiopathology, Diabetes Mellitus, Type 2:complications, Diabetic Neuropathies:diagnosis, Evoked Potentials, Motor:physiology, Evoked Potentials, Somatosensory:physiology, Humans, Middle Aged, Neu.   

OBJECTIVES: Diabetic neuropathy and autonomic nervous system neuropathy are recognized as the most common clinical pictures of nervous system disorders caused by diabetes mellitus (DM). Damage to the brain and the spinal cord is rare. The aim of this work is to show the importance of somatosensory and motor evoked potentials (SEP and MEP) for the early diagnosis of nervous system damage related to diabetes mellitus.

MATERIAL AND METHODS: We examined spinal and cortical somatosensory evoked potentials (SEP) after median and fibular nerve stimulation in diabetics and control subjects. We measured the latencies of individual wave deflections and peripheral and central conduction time (PCT and CCT) of spinal and cortical SEP. Similarly, transcranial magnetic stimulation was used for measuring the central and peripheral conduction time (CCT and PCT) in a group of type 1 diabetics and a control group of volunteers.

RESULTS: The examination SEP and MEP proved and confirmed the prolongation not only of peripheral conduction time, but also of the central conduction time - especially in spinal cord structures. An assumption that spinal cord changes are connected with the decreased number of myelinated fibers able to conduct the impulses from periphery and brain cortex, respectively, has to be accepted.

CONCLUSIONS: The results suggest that the use of somatosensory and motor evoked potentials (SEP and MEP) examination and conduction times measurement has significance in the confirmation of unapparent lesions of the spinal cord in diabetics of both types....

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