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P717: Ultrasonography of the sural nerve in patients with polyneuropathy
Abstracts of Poster Presentations / Clinical Neurophysiology 125, Supplement 1 (2014) S1–S339
hand muscles at rest. The RHI paradigm was applied to evoke multiple somatosensory illusory perceptions activating the PM and PPc. SAI and LAI were tested before and immediately after the induction of the illusory perception. SAI and LAI were assessed by comparing the conditioned to the unconditioned MEP amplitude. Results: At baseline, the average ratios of conditioned to unconditioned MEP were 0.71±0.19 for SAI and 0.71±0.14 for LAI, indicating sensory afferent inhibition. After RHI, the both ratios were slightly increased to 0.85±0.16 for SAI and 0.85±0.26 for LAI indicating a reduction of inhibition. Conclusions: Both short and long latency sensorimotor integration pathways appear to be involved in the processing of multisensory perceptions. The long-latency pathway may interact with cortical areas that are activated by the RHI paradigm such as the PM and PPc.
LP40 Transcranial magnetic stimulation (TMS) and mirror therapy: a promising rehabilitative approach for subacute stroke patients with severe disability D. Dalla Libera, D. Dinacci, A. Albini, G. Ruggieri, P. Rossi Hildebrand, Neurorehabilitation, Brissago, Switzerland Introduction: Mirror therapy (MT) has been proved to promote cortical reorganization and functional recovery of post-stroke patients. Also high frequency repetitive transcranial magnetic stimulation (TMS) - a noninvasive, safe tool that modulates local neuron excitability and induce short-time functional reorganization of cortical networks- has been recently studied for its contribution in stroke rehabilitation. The combination of the two techniques has not been explored. Methods: Three Patients affected by subacute first-ever stroke - documented by a brain CT- with severe disability (NIHSS 10-14) and hand paresis were recruited at 1 month from the event and received a complete neurological examination including MRC, NIHSS and Fugl-Meyer grading. They underwent 12 session (3 time/week) of 15 minutes of excitatory TMS through a circular coil applied on the primary motor cortex of the affected emisphere, followed by 15 minutes of MT for the upper limb (imitation of presented postures and motor imagery through repetitive active-passive limb movements, according to already existing protocols). Double-pulse TMS through a figure-eight focal coil was used to study intracortical inhibition (ICI) in primary motor cortex of both side at rest and during the preparation of movement. Mapping the motor cortex with TMS was also obtained in order to study acute and rapid plastic rearrangements of cortical motor output. Results: A motor evoked potentials - previously absent - was elicited after 1 month treatment for the affected upper limb. A normalization of the silent period - previously prolonged - and reduction of and intracortical inhibition in the affected emisphere was evident, together with a significant modification of ICI over the unaffected hemisphere. Such results were reproducible also one month after the end of treatment. Conclusion: TMS treatment combined with MT may be added to the conventional therapy of severely impaired stroke patients even in an early phase after the insult, with positive results on both neurophysiological and clinical parameters. We may suppose that TMS, when combined with MT enhances synaptic plasticity and induce nerugenesis, facilitating the motor recovery, even in those cases with predicted limited recovery offered by regular physical therapy.A follow-up study and an enlargement of the sample is ongoing.
LP41 Language mapping with nrTMS: an experimental study in 2 healthy speech therapists E. De Witte 1 , E. Verwilligen 2 , E. Robert 2,3 , H. Colle 3 1 Free University of Brussels, Clinical and Experimental Neurolinguistics, Brussels, Belgium; 2 AZ Maria Middelares Ghent, Department of speech pathology, Ghent, Belgium, Belgium; 3 AZ Sint-Lucas Ghent, Department of Neurolinguistics and Neurosurgery, Ghent, Belgium, Belgium Objective: The use of Navigated Transcranial Magnetic Stimulation (nTMS) in presurgical mapping is increasing. Good correlations have been found for TMS and Direct Electrical Stimulation (DES) when motor mapping is studied. Language mapping with TMS is far more complex. Repetitive TMS (rTMS) is required to disrupt language processing. The deficits typically reflect a delay in response times rather than a decline in accuracy, but
S247
rTMS may also cause “speech arrests”. The interpretation of speech arrests is often neglected, although it provides useful information regarding the specific function-location relationship. Methods: In this study we used for the first time two speech therapists as healthy subjects to study language mapping with TMS during a naming task. Firstly, we wanted to investigate if TMS elicits pure language problems or mainly motor speech problems. Secondly, anatomoclinical correlations were studied. At the first test moment (T1), the speech therapists had to name 210 low-, middle-, and highfrequent unknown coloured pictures. 3 weeks later (T2) and 3 months later (T3) naming was assessed using navigated repetitive TMS (nrTMS) of the left perisylvian regions. Afterwards, the speech therapists were asked to classify the errors into language/motor/apractogenic/other deficits. Results: There was a large interindividual difference since many more deficits were observed for speech therapist 2. Performance errors (dysartric/apractogenic distortions, restarts, prolonged reaction times) were the most frequently made errors followed by semantic paraphasias. Performance errors were triggered by stimulations in superior temporal gyrus, inferior frontal gyrus, supramarginal gyrus, precentral gyrus and angular gyrus. Semantic paraphasias were elicited when AG, PrCG and SMG were stimulated. There was a trend for prolonged reaction times at T2 versus T1. However, there was a significant difference between T1 versus T3 and T2 versus T3 with shorter RT at T3 for speech therapist 2. Conclusion: nrTMS might prolong reaction times and elicits motor speech deficits as well as language deficits. Since a clear learning effect was found at T3, the time between the three trials should be extended in future studies. The use of different language tasks in a larger study group would be interesting.
Poster session 40. Ultrasound P717 Ultrasonography of the sural nerve in patients with polyneuropathy C. Holbe, B. von Sarnowski, C. Kessler, U. Schminke Universitaet Greifswald, Greifswald, Germany Question: Although signs and symptoms of polyneuropathies (PNP) predominantly affect the lower limbs, our knowledge regarding changes in nerve caliber in patients with PNP is mainly based on ultrasonography studies, which investigated peripheral nerves of the upper limbs. We, therefore, aimed to explore structural changes of the sural nerve in patients suffering from PNP of various etiologies in comparison with healthy subjects. Methods: We measured the nerve’s cross-sectional area (NCSA) of the sural nerve at 3 pre-defined sites of each limb with high-resolution B-mode ultrasonography in 36 patients with PNP and 18 healthy controls and calculated the mean (mNCSA) of these 6 measurements. Results: In an overall analysis, the mNCSA did not differ significantly between patients and controls. However, we found a significantly higher mNCSA of the sural nerve in patients with an inflammatory type of PNP than in those with chronic idiopathic axonal PNP (M0.5 2.2mm2 , interquartile range (IQR) 1.2mm2 versus M0.5 1.7mm2 , IQR 0.5mm2 ; p=0.03). Conclusions: Our study demonstrates that inflammatory PNP are associated with an enlargement of the caliber of peripheral nerves, which occurs not only in large nerves of the upper limbs, but also in small nerves like the sural nerve.
Poster session 41. Depression and anxiety P721 Pre-treatment frontal quantitative EEG asymmetry as a predictor of antidepressant effects of low frequency rTMS in patients with major depression J. Krstic 1,2 , N. Rajsic 1 , S.D. Milanovic 3 , T.V. Ilic 1 1 Military Medical Academy, Clin Neurophysiology, Belgrade, Serbia; 2 Psychiatric Hospital, Clinical Hospital Center “Dr Dragisa Misovic”, Belgrade, Serbia; 3 Institute for Medical Research, University of Belgrade, Belgrade, Serbia Question: Low frequency repetitive transcranial magnetic stimulation (LF
hand muscles at rest. The RHI paradigm was applied to evoke multiple somatosensory illusory perceptions activating the PM and PPc. SAI and LAI were tested before and immediately after the induction of the illusory perception. SAI and LAI were assessed by comparing the conditioned to the unconditioned MEP amplitude. Results: At baseline, the average ratios of conditioned to unconditioned MEP were 0.71±0.19 for SAI and 0.71±0.14 for LAI, indicating sensory afferent inhibition. After RHI, the both ratios were slightly increased to 0.85±0.16 for SAI and 0.85±0.26 for LAI indicating a reduction of inhibition. Conclusions: Both short and long latency sensorimotor integration pathways appear to be involved in the processing of multisensory perceptions. The long-latency pathway may interact with cortical areas that are activated by the RHI paradigm such as the PM and PPc.
LP40 Transcranial magnetic stimulation (TMS) and mirror therapy: a promising rehabilitative approach for subacute stroke patients with severe disability D. Dalla Libera, D. Dinacci, A. Albini, G. Ruggieri, P. Rossi Hildebrand, Neurorehabilitation, Brissago, Switzerland Introduction: Mirror therapy (MT) has been proved to promote cortical reorganization and functional recovery of post-stroke patients. Also high frequency repetitive transcranial magnetic stimulation (TMS) - a noninvasive, safe tool that modulates local neuron excitability and induce short-time functional reorganization of cortical networks- has been recently studied for its contribution in stroke rehabilitation. The combination of the two techniques has not been explored. Methods: Three Patients affected by subacute first-ever stroke - documented by a brain CT- with severe disability (NIHSS 10-14) and hand paresis were recruited at 1 month from the event and received a complete neurological examination including MRC, NIHSS and Fugl-Meyer grading. They underwent 12 session (3 time/week) of 15 minutes of excitatory TMS through a circular coil applied on the primary motor cortex of the affected emisphere, followed by 15 minutes of MT for the upper limb (imitation of presented postures and motor imagery through repetitive active-passive limb movements, according to already existing protocols). Double-pulse TMS through a figure-eight focal coil was used to study intracortical inhibition (ICI) in primary motor cortex of both side at rest and during the preparation of movement. Mapping the motor cortex with TMS was also obtained in order to study acute and rapid plastic rearrangements of cortical motor output. Results: A motor evoked potentials - previously absent - was elicited after 1 month treatment for the affected upper limb. A normalization of the silent period - previously prolonged - and reduction of and intracortical inhibition in the affected emisphere was evident, together with a significant modification of ICI over the unaffected hemisphere. Such results were reproducible also one month after the end of treatment. Conclusion: TMS treatment combined with MT may be added to the conventional therapy of severely impaired stroke patients even in an early phase after the insult, with positive results on both neurophysiological and clinical parameters. We may suppose that TMS, when combined with MT enhances synaptic plasticity and induce nerugenesis, facilitating the motor recovery, even in those cases with predicted limited recovery offered by regular physical therapy.A follow-up study and an enlargement of the sample is ongoing.
LP41 Language mapping with nrTMS: an experimental study in 2 healthy speech therapists E. De Witte 1 , E. Verwilligen 2 , E. Robert 2,3 , H. Colle 3 1 Free University of Brussels, Clinical and Experimental Neurolinguistics, Brussels, Belgium; 2 AZ Maria Middelares Ghent, Department of speech pathology, Ghent, Belgium, Belgium; 3 AZ Sint-Lucas Ghent, Department of Neurolinguistics and Neurosurgery, Ghent, Belgium, Belgium Objective: The use of Navigated Transcranial Magnetic Stimulation (nTMS) in presurgical mapping is increasing. Good correlations have been found for TMS and Direct Electrical Stimulation (DES) when motor mapping is studied. Language mapping with TMS is far more complex. Repetitive TMS (rTMS) is required to disrupt language processing. The deficits typically reflect a delay in response times rather than a decline in accuracy, but
S247
rTMS may also cause “speech arrests”. The interpretation of speech arrests is often neglected, although it provides useful information regarding the specific function-location relationship. Methods: In this study we used for the first time two speech therapists as healthy subjects to study language mapping with TMS during a naming task. Firstly, we wanted to investigate if TMS elicits pure language problems or mainly motor speech problems. Secondly, anatomoclinical correlations were studied. At the first test moment (T1), the speech therapists had to name 210 low-, middle-, and highfrequent unknown coloured pictures. 3 weeks later (T2) and 3 months later (T3) naming was assessed using navigated repetitive TMS (nrTMS) of the left perisylvian regions. Afterwards, the speech therapists were asked to classify the errors into language/motor/apractogenic/other deficits. Results: There was a large interindividual difference since many more deficits were observed for speech therapist 2. Performance errors (dysartric/apractogenic distortions, restarts, prolonged reaction times) were the most frequently made errors followed by semantic paraphasias. Performance errors were triggered by stimulations in superior temporal gyrus, inferior frontal gyrus, supramarginal gyrus, precentral gyrus and angular gyrus. Semantic paraphasias were elicited when AG, PrCG and SMG were stimulated. There was a trend for prolonged reaction times at T2 versus T1. However, there was a significant difference between T1 versus T3 and T2 versus T3 with shorter RT at T3 for speech therapist 2. Conclusion: nrTMS might prolong reaction times and elicits motor speech deficits as well as language deficits. Since a clear learning effect was found at T3, the time between the three trials should be extended in future studies. The use of different language tasks in a larger study group would be interesting.
Poster session 40. Ultrasound P717 Ultrasonography of the sural nerve in patients with polyneuropathy C. Holbe, B. von Sarnowski, C. Kessler, U. Schminke Universitaet Greifswald, Greifswald, Germany Question: Although signs and symptoms of polyneuropathies (PNP) predominantly affect the lower limbs, our knowledge regarding changes in nerve caliber in patients with PNP is mainly based on ultrasonography studies, which investigated peripheral nerves of the upper limbs. We, therefore, aimed to explore structural changes of the sural nerve in patients suffering from PNP of various etiologies in comparison with healthy subjects. Methods: We measured the nerve’s cross-sectional area (NCSA) of the sural nerve at 3 pre-defined sites of each limb with high-resolution B-mode ultrasonography in 36 patients with PNP and 18 healthy controls and calculated the mean (mNCSA) of these 6 measurements. Results: In an overall analysis, the mNCSA did not differ significantly between patients and controls. However, we found a significantly higher mNCSA of the sural nerve in patients with an inflammatory type of PNP than in those with chronic idiopathic axonal PNP (M0.5 2.2mm2 , interquartile range (IQR) 1.2mm2 versus M0.5 1.7mm2 , IQR 0.5mm2 ; p=0.03). Conclusions: Our study demonstrates that inflammatory PNP are associated with an enlargement of the caliber of peripheral nerves, which occurs not only in large nerves of the upper limbs, but also in small nerves like the sural nerve.
Poster session 41. Depression and anxiety P721 Pre-treatment frontal quantitative EEG asymmetry as a predictor of antidepressant effects of low frequency rTMS in patients with major depression J. Krstic 1,2 , N. Rajsic 1 , S.D. Milanovic 3 , T.V. Ilic 1 1 Military Medical Academy, Clin Neurophysiology, Belgrade, Serbia; 2 Psychiatric Hospital, Clinical Hospital Center “Dr Dragisa Misovic”, Belgrade, Serbia; 3 Institute for Medical Research, University of Belgrade, Belgrade, Serbia Question: Low frequency repetitive transcranial magnetic stimulation (LF