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P07.12 Electrophysiological investigation of botulinum toxin effect mechanism on hemifacial spasm
Posters / Clinical Neurophysiology 117 (2006) S121–S336
Results: There was no significant change in the amplitude or latency of soleus Mmax during soleus muscle stretch in comparison with controls (>0.05). During ipsilateral soleus muscle stretch, Hmax amplitude was depressed by 62.2% ± 12.5%, ranging from 46.2% to 85.7%. There was no significant change in Hmax amplitude during contra lateral soleus muscle stretch (p > 0.05). Discussion: The results suggest that muscle lengthening is an important factor of premotoneuronal events in determining the amplitude of soleus H-reflex. The steady firing in the Ia sensory fiber during muscle stretch might affect the responsiveness of Ia afferents to electrical stimulation during H-reflex testing, which might be a contributing factor in depressing soleus H-reflex. This may have practical implications in using the H-reflex as a tool to test the spinal motor neuron excitability in motor control neurophysiology. doi:10.1016/j.clinph.2006.06.279
P07.11 Blink reflex recovery curve in tetanus J. Urriza Mena, L. Gila Useros, L. Gonzalez Rojas, L. Imirizaldu Monente, O. Olaziregi Zabaleta Hospital Virgen del Camino, Servicio de Neurofisiologia Clinica, Spain Background: We present a case of local tetanus, with trismus as initial symptom, in which the electromyography (EMG) and the brain stem reflexes were indicative. The blink reflex recovery curve (BRRC) was determinant in the final diagnosis. Aim: To describe the electrophysiologic abnormalities found in a case of tetanus, and specially the disturbance on the BRRC, to our knowledge not reported until now. Patient and methods: We present a patient, women, HIV(+), addicted to drugs, with progressive trismus.The most common causes of trismus were ruled out. Surface and needle EMG, Startle, Blink Reflex, Masseteric Reflex, Masseteric stretch and electric Inhibitory Reflex and BRRC studies were performed. Results: Recruitment spasms, sustained contraction, and difficulty in relaxation on the EMG study, without startle reaction, reflex spasms nor spreading of the EMG bursts were documented. Along with this, diminished duration of the first silent period and no second silent period on electrically induced masseteric inhibitory reflex were found. Sustained contraction on blink reflex after R2 and a clear disturbance of the BRRC for R2, in the form of a lost of the normal inhibition, along with a normal behavior of the BBRC of R1 were also found. Discussion/conclusion: These abnormalities reflect alterations on inhibitory circuits at the brainstem level, and specially a disturbance of the BRRC of R2. From a practical point of view, it points at an abnormal function of the
S163
brainstem interneurons where the simptomatology and the usual reflexes studies could be doubtful. doi:10.1016/j.clinph.2006.06.280
P07.12 Electrophysiological investigation of botulinum toxin effect mechanism on hemifacial spasm T. Kurt 1, Y. Secil 1, N. Gurgor 1, Y. Yetimalar 1, M. Basoglu 1, C. Ertekin 2 1
Ataturk Education and Research Hospital, Neurology, Turkey 2 Ege University Medical School Hospital, Clinical Neurophysiology Department, Neurology, Turkey Background: The aim of this study was to investigate the effects of botulinum toxin (BTx) on fascial motor neuron excitability in hemifacial spasm (HS) patients. Materials and methods: Twenty eight idiopathic HS patients were electrophysiologically evaluated on abnormal and normal fascial sides before and 3 weeks after the BTx treatment. Needle EMG of the orbicularis oculi, orbicularis oris and frontalis muscles was performed, motor conduction of facial nerve to these muscles and bilateral blink reflexes were examined. The lateral spreading phenomenon on the pathological side in 14 patients was evaluated before and after the treatment. Results: Before BTx injection, motor conductions and blink reflex parameters between normal and pathological sides did not show significant difference. After BTx, motor conduction and blink reflex R1 latencies of abnormal side o.oculi were found to be prolonged. Blink reflex R1 and R2 latencies on the abnormal side were found to be prolonged after treatment when compared to normal side. Ipsilateral o. oris blink reflex R1 and R2 latencies on the abnormal side obtained by supraorbital stimulation did not show any significant difference before and after BTx. O.oculi response recorded by stimulation of mental branch of fascial nerve could not be recorded on the abnormal side after BTx, in 12 patients. Conclusion: The results of this study indicate that BTx shows its effect only on the muscle that it is applied and does not have any effect on the fascial motor neuron excitability in HS patients. doi:10.1016/j.clinph.2006.06.281
P07.13 A wave and pain: a model based on leprosy neuropathy follow-up J. Garbino 1, M. Virmond 1, M. Salgado 2, S. Ura 1, B. Naafs 3 1 2 3
Research Institute ‘‘Lauro de Souza Lima’’, Brazil Universidade Estadual de Sa˜o Paulo, Brazil Leiden University, Netherlands
Results: There was no significant change in the amplitude or latency of soleus Mmax during soleus muscle stretch in comparison with controls (>0.05). During ipsilateral soleus muscle stretch, Hmax amplitude was depressed by 62.2% ± 12.5%, ranging from 46.2% to 85.7%. There was no significant change in Hmax amplitude during contra lateral soleus muscle stretch (p > 0.05). Discussion: The results suggest that muscle lengthening is an important factor of premotoneuronal events in determining the amplitude of soleus H-reflex. The steady firing in the Ia sensory fiber during muscle stretch might affect the responsiveness of Ia afferents to electrical stimulation during H-reflex testing, which might be a contributing factor in depressing soleus H-reflex. This may have practical implications in using the H-reflex as a tool to test the spinal motor neuron excitability in motor control neurophysiology. doi:10.1016/j.clinph.2006.06.279
P07.11 Blink reflex recovery curve in tetanus J. Urriza Mena, L. Gila Useros, L. Gonzalez Rojas, L. Imirizaldu Monente, O. Olaziregi Zabaleta Hospital Virgen del Camino, Servicio de Neurofisiologia Clinica, Spain Background: We present a case of local tetanus, with trismus as initial symptom, in which the electromyography (EMG) and the brain stem reflexes were indicative. The blink reflex recovery curve (BRRC) was determinant in the final diagnosis. Aim: To describe the electrophysiologic abnormalities found in a case of tetanus, and specially the disturbance on the BRRC, to our knowledge not reported until now. Patient and methods: We present a patient, women, HIV(+), addicted to drugs, with progressive trismus.The most common causes of trismus were ruled out. Surface and needle EMG, Startle, Blink Reflex, Masseteric Reflex, Masseteric stretch and electric Inhibitory Reflex and BRRC studies were performed. Results: Recruitment spasms, sustained contraction, and difficulty in relaxation on the EMG study, without startle reaction, reflex spasms nor spreading of the EMG bursts were documented. Along with this, diminished duration of the first silent period and no second silent period on electrically induced masseteric inhibitory reflex were found. Sustained contraction on blink reflex after R2 and a clear disturbance of the BRRC for R2, in the form of a lost of the normal inhibition, along with a normal behavior of the BBRC of R1 were also found. Discussion/conclusion: These abnormalities reflect alterations on inhibitory circuits at the brainstem level, and specially a disturbance of the BRRC of R2. From a practical point of view, it points at an abnormal function of the
S163
brainstem interneurons where the simptomatology and the usual reflexes studies could be doubtful. doi:10.1016/j.clinph.2006.06.280
P07.12 Electrophysiological investigation of botulinum toxin effect mechanism on hemifacial spasm T. Kurt 1, Y. Secil 1, N. Gurgor 1, Y. Yetimalar 1, M. Basoglu 1, C. Ertekin 2 1
Ataturk Education and Research Hospital, Neurology, Turkey 2 Ege University Medical School Hospital, Clinical Neurophysiology Department, Neurology, Turkey Background: The aim of this study was to investigate the effects of botulinum toxin (BTx) on fascial motor neuron excitability in hemifacial spasm (HS) patients. Materials and methods: Twenty eight idiopathic HS patients were electrophysiologically evaluated on abnormal and normal fascial sides before and 3 weeks after the BTx treatment. Needle EMG of the orbicularis oculi, orbicularis oris and frontalis muscles was performed, motor conduction of facial nerve to these muscles and bilateral blink reflexes were examined. The lateral spreading phenomenon on the pathological side in 14 patients was evaluated before and after the treatment. Results: Before BTx injection, motor conductions and blink reflex parameters between normal and pathological sides did not show significant difference. After BTx, motor conduction and blink reflex R1 latencies of abnormal side o.oculi were found to be prolonged. Blink reflex R1 and R2 latencies on the abnormal side were found to be prolonged after treatment when compared to normal side. Ipsilateral o. oris blink reflex R1 and R2 latencies on the abnormal side obtained by supraorbital stimulation did not show any significant difference before and after BTx. O.oculi response recorded by stimulation of mental branch of fascial nerve could not be recorded on the abnormal side after BTx, in 12 patients. Conclusion: The results of this study indicate that BTx shows its effect only on the muscle that it is applied and does not have any effect on the fascial motor neuron excitability in HS patients. doi:10.1016/j.clinph.2006.06.281
P07.13 A wave and pain: a model based on leprosy neuropathy follow-up J. Garbino 1, M. Virmond 1, M. Salgado 2, S. Ura 1, B. Naafs 3 1 2 3
Research Institute ‘‘Lauro de Souza Lima’’, Brazil Universidade Estadual de Sa˜o Paulo, Brazil Leiden University, Netherlands