Motor evoked potentials (MEPs) in lacunar syndromes.

Motor evoked potentials (MEPs) evoked in the biceps, thenar and tibialis anterior muscles by electrical stimulation of the scalp and of the spinal regions were recorded in 32 patients with focal deficits due to minor cerebral ischemia of the lacunar type and in a control group. Somatosensory evoked potentials (SEPs) to median nerve stimulation were also recorded. The central motor conduction times (CMCTs) and the threshold intensities for eliciting MEPs in the relaxed muscles were significantly increased on the affected side. Central motor conduction, for at least one muscle, was altered in 18 patients. MEP abnormalities were related to pyramidal signs (though they could be observed also in a patient without any motor impairment) and occurred independently of a specific clinical picture or a radiologically confirmed lacunar lesion. SEPs were less frequently altered than MEPs.

[1]  G. Donnan,et al.  A comparison of somatosensory evoked and motor evoked potentials in stroke , 1989, Annals of neurology.

[2]  A Berardelli,et al.  Cortical and cervical stimulation after hemispheric infarction. , 1987, Journal of neurology, neurosurgery, and psychiatry.

[3]  L. Weisberg.  Lacunar infarcts: clinical and computed tomographic correlations. , 1982, Archives of neurology.

[4]  A. Berardelli.  2 – Cortical stimulation in patients with motor disturbances , 1990 .

[5]  Christopher O'Brien,et al.  Motor Disturbances II , 1991 .

[6]  J E Desmedt,et al.  Color imaging of parietal and frontal somatosensory potential fields evoked by stimulation of median or posterior tibial nerve in man. , 1985, Electroencephalography and clinical neurophysiology.

[7]  B. Day,et al.  Electric and magnetic stimulation of human motor cortex: surface EMG and single motor unit responses. , 1989, The Journal of physiology.

[8]  M. Swash,et al.  Central motor conduction in multiple sclerosis: evaluation of abnormalities revealed by transcutaneous magnetic stimulation of the brain. , 1988, Journal of neurology, neurosurgery, and psychiatry.

[9]  P. Rossini,et al.  Mechanisms of nervous propagation along central motor pathways: noninvasive evaluation in healthy subjects and in patients with neurological disease. , 1987, Neurosurgery.

[10]  M G Marciani,et al.  Non-invasive evaluation of input-output characteristics of sensorimotor cerebral areas in healthy humans. , 1987, Electroencephalography and clinical neurophysiology.

[11]  H. Morton,et al.  Stimulation of the cerebral cortex in the intact human subject , 1980, Nature.

[12]  J. C. Rothwell,et al.  The interpretation of electromyographic responses to electrical stimulation of the motor cortex in diseases of the upper motor neurone , 1987, Journal of the Neurological Sciences.

[13]  F Mauguière,et al.  Astereognosis and dissociated loss of frontal or parietal components of somatosensory evoked potentials in hemispheric lesions. Detailed correlations with clinical signs and computerized tomographic scanning. , 1983, Brain : a journal of neurology.

[14]  E. Favale,et al.  Electrical stimulation of the motor tracts in cervical spondylosis. , 1988, Journal of neurology, neurosurgery, and psychiatry.

[15]  High-voltage stimulation over the human spinal cord: sources of latency variation. , 1989, Journal of neurology, neurosurgery, and psychiatry.

[16]  C. Fisher.  Lacunar strokes and infarcts , 1982, Neurology.

[17]  P. Thompson,et al.  Motor cortex stimulation in intact man. 1. General characteristics of EMG responses in different muscles. , 1987, Brain : a journal of neurology.

[18]  J. Desmedt,et al.  Thalamic pain syndrome of Dejérine-Roussy. Differentiation of four subtypes assisted by somatosensory evoked potentials data. , 1988, Archives of neurology.

[19]  E. Favale,et al.  Abnormalities of parietal and prerolandic somatosensory evoked potentials in Huntington's disease. , 1990, Electroencephalography and clinical neurophysiology.

[20]  P. Rossini,et al.  Electric vs magnetic trans-cranial stimulation of the brain in healthy humans: a comparative study of central motor tracts ‘conductivity’ and ‘excitability’ , 1989, Brain Research.

[21]  N. Murray,et al.  Electrical stimulation over the human vertebral column: which neural elements are excited? , 1986, Electroencephalography and clinical neurophysiology.

[22]  A. Barker,et al.  NON-INVASIVE MAGNETIC STIMULATION OF HUMAN MOTOR CORTEX , 1985, The Lancet.

[23]  N. Accornero,et al.  Stimulation of motor tracts in multiple sclerosis. , 1988, Journal of neurology, neurosurgery, and psychiatry.

[24]  M Hallett,et al.  Noninvasive mapping of human motor cortex , 1988, Neurology.

[25]  P. Thompson,et al.  Percutaneous electrical stimulation of lumbosacral roots in man. , 1988, Journal of neurology, neurosurgery, and psychiatry.