Cortically Evoked Motor Action Potential in Spinal Cord Injury Research

Patil, Arun-Angelo; Nagaraj, M. P.; Mehta, Ranbeer Kumar

doi:10.1097/00006123-198504000-00007

Cited by 10 publications

(1 citation statement)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This assumption might be corroborated by a study of artificially induced SCI in rats; it reported about disappearance of motor evoked potentials after application of 60 g pressure for 10 seconds and reappearance of waves with lower amplitudes approximately 30 minutes later. 45 TMMEP latency and amplitude are affected by changes in axonal myelination that result in altered conductivity and axonal integrity. Axonal demyelination is a prominent feature of SCI, and spontaneous remyelination of axons is considered to contribute to neurological recovery.…”

Section: Discussionmentioning

confidence: 99%

Transcranial magnetic motor evoked potentials and magnetic resonance imaging findings in paraplegic dogs with recovery of motor function

Siedenburg

Wang‐Leandro

Amendt

et al. 2018

Veterinary Internal Medicne

View full text Add to dashboard Cite

BackgroundTranscranial magnetic motor evoked potentials (TMMEP) are associated with severity of clinical signs and magnetic resonance imaging (MRI) findings in dogs with spinal cord disease.HypothesisThat in initially paraplegic dogs with thoracolumbar intervertebral disc herniation (IVDH), MRI findings before surgery and TMMEPs obtained after decompressive surgery are associated with long‐term neurological status and correlate with each other.AnimalsSeventeen client‐owned paraplegic dogs with acute thoracolumbar IVDH.MethodsProspective observational study. TMMEPs were obtained from pelvic limbs and MRI (3T) of the spinal cord was performed at initial clinical presentation. Follow‐up studies were performed ≤ 2 days after reappearance of motor function and 3 months later. Ratios of compression length, intramedullary hyperintensities' length (T2‐weighted hyperintensity length ratio [T2WLR]), and lesion extension (T2‐weighted‐lesion extension ratio) in relation to the length of the 2nd lumbar vertebral body were calculated.ResultsTMMEPs could be elicited in 10/17 (59%) dogs at 1st and in 16/17 (94%) dogs at 2nd follow‐up. Comparison of TMMEPs of 1st and 2nd follow‐up showed significantly increased amplitudes (median from 0.19 to 0.45 mV) and decreased latencies (from 69.38 to 40.26 ms; P = .01 and .001, respectively). At 2nd follow‐up latencies were significantly associated with ambulatory status (P = .024). T2WLR obtained before surgery correlated with latencies at 2nd follow‐up (P = .04).ConclusionsTMMEP reflect motor function recovery after severe spinal cord injury.

show abstract

Section: Discussionmentioning

confidence: 99%

Transcranial magnetic motor evoked potentials and magnetic resonance imaging findings in paraplegic dogs with recovery of motor function

Siedenburg

Wang‐Leandro

Amendt

et al. 2018

Veterinary Internal Medicne

View full text Add to dashboard Cite

show abstract

Estimate of motor conduction in human spinal cord: Slowed conduction in spinal cord injury

Chang

Lien

1991

Muscle and Nerve

View full text Add to dashboard Cite

By using motor evoked potential (MEP) created by transcranial electric stimulation over the motor cortex and F-wave measurement from the peripheral nerve stimulation, it is possible to estimate the spinal cord motor conduction velocity (SCMCV) in the diseased state. Twenty-four patients with spinal cord injury (SCI) between T1 and T11 neurological levels participated in this study. MEP in leg muscle was absent in all neurologically complete paraplegics. In 16 patients with neurologically incomplete SCI, MEP was obtained in 13 patients. The SCMCV estimated from C7 to T12 spinal levels was 32.1 (SD = 9.4) m/s. This was significantly slower than 63.3 (SD = 8.6) m/s in 40 normal controls. This noninvasive, indirect method is measurable, and can provide valuable electrophysiological data in the assessment of motor function in patients with SCI.

show abstract

A study of motor and sensory evoked potentials in chronic cauda equina compression of the dog

Kim

Yang

1996

Eur Spine J

View full text Add to dashboard Cite

Previous experimental studies have shown the effects of acute compression of the spinal cord and peripheral nerve roots. Recently, however, a few studies of chronic compression of the cauda equina in animal models have been reported. The purpose of this study was to determine the long-term electrophysiologic changes resulting from chronic compression of the cauda equina in dogs. An animal model of lumbar spinal stenosis was prepared according to Delamarter's method. Four experimental groups, each containing six dogs, were studied. One group underwent only laminectomy of the sixth and seventh lumbar vertebrae; these animals served as controls. In the three other groups, a laminectomy was performed and the cauda equina was constricted by 25%, 50%, and 75%, respectively, to produce chronic compression. Weekly neurologic examinations were carried out, and the neurologic deficits were graded using a modified Tarlov system. Sensory, and motor evoked potentials were recorded preoperatively, immediately after constriction, and at 2 weeks and 1, 2, and 3 months postoperatively. The animals in the control group showed no changes in sensory or motor evoked potentials. The dogs in which the cauda equina had been constricted by 25% showed no neurologic deficits and only mild changes in sensory and motor evoked potentials. The dogs in which the cauda equina had been constricted by 50% showed mild initial motor weakness, and major changes in the evoked potentials. The dogs in which the cauda equina had been constricted by 75% showed significant weakness, paralysis of the tail, and urinary incontinence; all dogs were partially recovered by the 3rd month, but all still showed neurogenic changes in the evoked potentials. Sensory and motor evoked potentials revealed neurologic abnormalities before the appearance of neurologic signs and symptoms. Constriction of more than 50% was the critical point that resulted in complete loss or reduction of the evoked potentials and in neurologic deficits. Dogs in which motor and sensory evoked potentials recovered also showed gradual disappearance of neurologic symptoms and signs. Recovery of motor evoked potentials in particular was associated with complete disappearance of neurologic symptoms and signs. For accurate prognosis in cases of chronic cauda equina compression, a combined diagnostic study of sensory and motor evoked potentials is recommended.

show abstract

Cortically Evoked Motor Action Potential in Spinal Cord Injury Research

Cited by 10 publications

References 0 publications

Transcranial magnetic motor evoked potentials and magnetic resonance imaging findings in paraplegic dogs with recovery of motor function

Transcranial magnetic motor evoked potentials and magnetic resonance imaging findings in paraplegic dogs with recovery of motor function

Estimate of motor conduction in human spinal cord: Slowed conduction in spinal cord injury

A study of motor and sensory evoked potentials in chronic cauda equina compression of the dog

Contact Info

Product

Resources

About