- Email: [email protected]
16. Electrical activities during abnormal muscle contractions in a patient with rippling muscle disease
e150
Society Proceedings / Clinical Neurophysiology 120 (2009) e147–e180
Go stimulus after a cue stimulus presented on the monitor and ignored the other three stimuli. The one of the three NoGo stimuli is visually most similar to the Go stimulus (similar condition), and another is most distinct from it (distinct condition). We obtained ERPs of the Go and NoGo conditions from 13-channel EEG recordings and measured peak latency, amplitude, and topographic distribution of the NoGo-N2 and NoGo-P3 components. Commission error was highest for the NoGo stimulus of the similar condition. The amplitude of NoGo-P3 was largest and the latency shortest in the distinct condition. The amplitude of NoGo-N2 was highest and distributed in relatively anterior regions in the similar condition. These results suggested that the conflict condition with visual difficulty of tasks may activate anterior cingulate cortex and prefrontal cortex. doi:10.1016/j.clinph.2009.02.018
13. Utility of functional MRI using calculation task in neurosurgery—Takahiro Ota, Kyousuke Kamada, Shigeki Aoki, Nobuhito Saito (University of Tokyo, Tokyo, Japan) Background and purpose: We used functional MRI to visualize calculation centers in the parietal lobe, and demonstrated a correlation between sequential changes of fMRI results and calculation ability after neurological surgery. Methods: Fifteen subjects were studied, including 5 normal controls and 10 patients with brain lesions. The calculation task was to simply add three numbers projected onto a screen (addition task) and to multiply two one-digit numbers (multiplication task). Results: Functional MRI showed active pixels in bilateral interparietal sulcus (especially in dominant hemisphere) in all subjects. Mean values and standard deviation of left/right ratios of active pixels in the interparietal sulcus in neurosurgical patients were almost the same in normal controls. Conclusions: Functional MRI is a useful technique for noninvasive preoperative mapping of calculation centers. In the two patients with parietal lesions, postoperative functional MRI well reflected their calculation ability. We should preserve the interparietal sulcus in the dominant hemisphere to maintain calculation ability. doi:10.1016/j.clinph.2009.02.019
14. Efficacy and limitation of the conventional neonatal EEG for extremely low birth weight infants—Tetsuo Kubota, Hiroyuki Kidokoro, Tetsuo Hattori (Anjo Kosei Hospital, Anjo, Japan) It is well known that neonatal EEG is a powerful tool for the diagnosis and the assessment of prognosis of brain injuries in the preterm infant. According to the abnormal EEG patterns, we could predict the future cerebral palsy or mental retardation in these patients. The recent increase in the survival rate of very preterm infants has resulted in an increasing incidence of neurological sequelae. The sequelae are not only motor but also various cognitive disorders. We focused on the extremely low birth weight infants (ELBWI) and compared predictive values with term equivalent MRI and sequential EEG study in the NICU. As well as previous reports, we found that the term equivalent MRI could predict the later motor and cognitive disorders. In the EEG study, though we also predicted their neurological sequlae, the predictive values of neurological sequelae were less than those of MRI. We considered that these causes were the difficulties of detection with abnormal EEG findings
in ELBWI and restriction of the very early recording for their weak skins. In the future, we will have to examine the EEG findings more carefully and find the new characteristic and predictable EEG activities for later functional disorders of ELBWI. doi:10.1016/j.clinph.2009.02.020
15. Learning about advantageous decision-making influences subsequent sleep—Takashi Abe, Yoko Komada, Yuichi Inoue, Tadao Hori (Hiroshima University, Higashi-Hiroshima, Japan) This study was aimed to investigate the relationship between learning of advantageous decision-making and subsequent sleep. Eight healthy volunteers participated in this study (two men and six women, 20–24 years old, mean 21.9 years), and all of them assigned to both learning and control conditions. Polysomnograms were recorded after modified version of Iowa Gambling Task (Bechara et al., 1994) in learning condition and after control task in control condition. The control task was the task which did not need to learn the advantageous choice since the profile of all the choices was same. As a result of comparing the sleep variables of the learning condition and control condition, rapid eye movements (REM) density in learning condition was significantly greater than control condition. Moreover, increased REM density from control condition to learning condition predicted post-sleep increment of the number of choices from advantageous decision-making. This result suggests that offline memory reprocessing about the learning of advantageous decision-making occurs in relation to rapid eye movements in REM sleep. doi:10.1016/j.clinph.2009.02.021
16. Electrical activities during abnormal muscle contractions in a patient with rippling muscle disease—Takakuni Maki, Riki Matsumoto, Takayuki Kondo, Insuk Son, Takahiro Mezaki, Ichizo Nishino, Akio Ikeda, Nobuo Kohara, Ryosuke Takahashi (Kyoto University, Kyoto, Japan) Objective: To determine the electrophysiological trait of rippling muscle disease (RMD). Background: RMD is a myopathy with symptoms and signs of muscular hyperirritability characterized by percussion-induced rapid muscle contractions (PIRCs) and involuntary rolling muscle contractions (muscle rippling) provoked by mechanical stimuli and stretch. Most reports have shown that these abnormal muscle contractions were electrically silent, i.e., no action potentials in electromyogram. However, a few studies were against the notion, and the pathophysiology needs to be clarified by detail electrophysiological investigation. Methods: Subject is a 30-year-old man with RMD diagnosed by a reduced expression of caveolin-3 in the sarcolemma and missense mutation Arg27Gln in a caveolin-3 gene. Abnormal muscle contractions were investigated simultaneously with electromyogram and ultrasound. Results: During muscle rippling of the quadriceps femoris, the ultrasound study revealed rolling muscle contractions not only in superficial parts but also in deep parts. Needle electromyogram of the muscle rippling and PIRCs revealed electrical activities with short duration (<2 ms). The activities were not well recorded with surface electromyogram. This most likely represented single-fiber potentials rather than motor-unit potentials.
Society Proceedings / Clinical Neurophysiology 120 (2009) e147–e180
Conclusions: The existence of electrical activities was demonstrated during abnormal muscle contractions in a patient with genetically-confirmed RMD.
e151
of visual function using VEPs may contribute to prevent postoperative visual dysfunction. doi:10.1016/j.clinph.2009.02.024
doi:10.1016/j.clinph.2009.02.022
17. Inadequate spinal inhibitory control in a patient with Stiffperson syndrome—Hiroshi Morita, Minori Kodaira, Shu-ichi Ikeda (Shinshu University, Matsumoto, Japan) Spinal inhibitory reflexes were studied in a patient with anti-GAD positive Stiff-person syndrome. The extents of conditioning stimulus effects to soleus H-reflexes elicited with tibial nerve stimulation. Common peroneal nerve (CPN) were stimulated to evoke reciprocal Ia and D1 inhibition, and tendon of biceps femoris was mechanically tapped to evoke long lasting presynaptic inhibition (PSI). CPN stimulation elicited no reciprocal Ia inhibition, but short latency low threshold facilitation. The extent of D1 and PSI was smaller than the normal subject. With improvement of symptoms with Rituximab, the size of the maximal H-reflex decreased (before 38 2:5% of Mmax, after 26 2:7; P < 0:001Þ and H/M threshold ratio increased (before 62%, after 80%). The extent of PSI also increased with treatment (before 86 12% of control, after 69 17; P >< 0:05), but other inhibition did not increased significantly. The decrease in abnormal short latency facilitation was not significant (before 134 21% of control, after 122 19%). The impairment of spinal inhibitory system such as presynaptic inhibition is a possible mechanism for muscle stiffness in Stiff-person syndrome. doi:10.1016/j.clinph.2009.02.023
18. Intraoperative estimation of visual function using visual evoked potential—Tatsuya Sasaki 1, Takeshi Itakura 1, Kyouichi Suzuki 2, Yuka Matsumoto 1, Hitoshi Ando 1, Hiromichi Kasuya 1, Hiroyuki Muramatsu 1, Tsuyoshi Ichikawa 1, Taku Sato 1, Jun Sakum 1 (1 Fukushima Medical University, Fukushima, Japan, 2 Fukushima Red Cross Hospital, Fukushima, Japan) Intraoperative estimation of visual function using visual evoked potentials (VEPs) was performed. We developed a new light-stimulating device and recorded electroretinograms (ERGs) to ascertain retinal visual stimulation under total venous anesthesia. Stable ERG and VEP recordings were obtained in 207 of 220 eyes. In 12, ERG was recorded but VEP could not be recorded, probably because of visual dysfunction. The disappearance of ERG and VEP in the 13th eye after frontal scalp–flap reflection suggested technical failure. The criterion for VEP amplitude changes was defined as a 50% increase or decrease. In one of 207 eyes we observed an amplitude increase and functional improvement in vision. In 19 of 188 eyes without VEP changes, visual function improved, while in 167 no functional changes were observed, and in 2 visual function worsened (one patient developed a slight visual field defect in both eyes). In 4 eyes with VEP deterioration and subsequent recovery upon changing the operative maneuver; visual function improved in one and exhibited no change in three. The VEP amplitude decreased without subsequent recovery in 14 eyes; all of these developed various degrees of visual dysfunction. e could record intraoperative VEPs in almost all cases except for patients with severe visual dysfunction. None of patients without a decreased VEP amplitude showed apparent postoperative deterioration in visual function, suggesting that intraoperative estimation
19. Facial nerve motor evoked potential monitoring during microvascular decompression for hemifacial spasm—Masafumi Fukuda, Makoto Oishi, Yukihiko Fujii (University of Niigata, Niigata, Japan) To determine whether monitoring facial nerve motor evoked potentials (FNMEPs) elicited by transcranial electrical stimulation during microvascular decompression for hemifacial spasm (HFS) is useful for predicting postoperative outcome. We analyzed FNMEP findings in 25 patients with HFS. Corkscrew electrodes positioned at C3 or C4 and Cz were used to deliver supramaximal stimuli (152–450 V). FNMEPs were recorded from the orbicularis oculi, mentalis, and orbicularis oris muscles. The post-to-predecompression FNMEP ratios (shown as percentages) were used for analysis. Not only FNMEPs but also lateral spread responses (LSRs) were monitored to confirm complete decompression of the facial nerve. Twenty-four of 25 patients had no symptoms postoperatively. In those patients, LSRs disappeared completely or the LSR amplitude decreased markedly, and the amplitude of the FNMEPs obtained from the orbicularis oculi muscle significantly decreased after decompression ðp < 0:0005Þ. The FNMEP ratio in the orbicularis oculi muscle (44%) was significantly lower than that in the mentalis muscle (96%), or in the orbicularis oris (84%). In the only one patient, who showed no changes in both the LSR and FNMEP waveforms, mild HFS had remained 8 months after surgery. In HFS patients, a reduction in FNMEP amplitude obtained from the orbicularis oculi after microvascular decompression suggests normalization of excitability of the facial nerve. FNMEP monitoring during surgery as well as LSR monitoring can predict postoperative outcome in HFS patients. doi:10.1016/j.clinph.2009.02.025
20. Hybrid assistive neuromuscular dynamic stimulation (HANDS) therapy in patients with chronic stroke—Toshiyuki Fujiwara, Yoshihiro Muraoka, Tetsuya Tsuji, Kimitaka Hase, Yoshihisa Masakado, Akio Kimura, Meigen Liu (Keio University School of Medicine, Tokyo, Japan) We devised a therapeutic approach to facilitate the use of the paretic UE in daily life by combining integrated volitional control electrical stimulation with a wrist splint, the HANDS therapy. The aim of this study is to assess its effects on selected measures of hand function and electrophysiological measurements. Participants were 30 patients with chronic hemiparetic stroke. Before and immediately after 3 weeks of training and wearing the system for 8 h each day, clinical measures of motor impairment, amount of use of paretic hand in ADL, as well as neurophysiological measures including reciprocal inhibition and intracortical inhibition were assessed. The follow-up clinical assessment was performed 3 months later. UE motor function improved after the intervention. The amount of use of the paretic hand in ADL had been increased. The intervention induced restoration of presynaptic and long loop inhibitory connections as well as disynaptic reciprocal inhibition. Paired pulse TMS study indicated disinhibition of the short intracortical inhibition in the affected hemisphere. The follow-up assessment showed that improvements were maintained at 3 months. The HANDS therapy is suggested to
Society Proceedings / Clinical Neurophysiology 120 (2009) e147–e180
Go stimulus after a cue stimulus presented on the monitor and ignored the other three stimuli. The one of the three NoGo stimuli is visually most similar to the Go stimulus (similar condition), and another is most distinct from it (distinct condition). We obtained ERPs of the Go and NoGo conditions from 13-channel EEG recordings and measured peak latency, amplitude, and topographic distribution of the NoGo-N2 and NoGo-P3 components. Commission error was highest for the NoGo stimulus of the similar condition. The amplitude of NoGo-P3 was largest and the latency shortest in the distinct condition. The amplitude of NoGo-N2 was highest and distributed in relatively anterior regions in the similar condition. These results suggested that the conflict condition with visual difficulty of tasks may activate anterior cingulate cortex and prefrontal cortex. doi:10.1016/j.clinph.2009.02.018
13. Utility of functional MRI using calculation task in neurosurgery—Takahiro Ota, Kyousuke Kamada, Shigeki Aoki, Nobuhito Saito (University of Tokyo, Tokyo, Japan) Background and purpose: We used functional MRI to visualize calculation centers in the parietal lobe, and demonstrated a correlation between sequential changes of fMRI results and calculation ability after neurological surgery. Methods: Fifteen subjects were studied, including 5 normal controls and 10 patients with brain lesions. The calculation task was to simply add three numbers projected onto a screen (addition task) and to multiply two one-digit numbers (multiplication task). Results: Functional MRI showed active pixels in bilateral interparietal sulcus (especially in dominant hemisphere) in all subjects. Mean values and standard deviation of left/right ratios of active pixels in the interparietal sulcus in neurosurgical patients were almost the same in normal controls. Conclusions: Functional MRI is a useful technique for noninvasive preoperative mapping of calculation centers. In the two patients with parietal lesions, postoperative functional MRI well reflected their calculation ability. We should preserve the interparietal sulcus in the dominant hemisphere to maintain calculation ability. doi:10.1016/j.clinph.2009.02.019
14. Efficacy and limitation of the conventional neonatal EEG for extremely low birth weight infants—Tetsuo Kubota, Hiroyuki Kidokoro, Tetsuo Hattori (Anjo Kosei Hospital, Anjo, Japan) It is well known that neonatal EEG is a powerful tool for the diagnosis and the assessment of prognosis of brain injuries in the preterm infant. According to the abnormal EEG patterns, we could predict the future cerebral palsy or mental retardation in these patients. The recent increase in the survival rate of very preterm infants has resulted in an increasing incidence of neurological sequelae. The sequelae are not only motor but also various cognitive disorders. We focused on the extremely low birth weight infants (ELBWI) and compared predictive values with term equivalent MRI and sequential EEG study in the NICU. As well as previous reports, we found that the term equivalent MRI could predict the later motor and cognitive disorders. In the EEG study, though we also predicted their neurological sequlae, the predictive values of neurological sequelae were less than those of MRI. We considered that these causes were the difficulties of detection with abnormal EEG findings
in ELBWI and restriction of the very early recording for their weak skins. In the future, we will have to examine the EEG findings more carefully and find the new characteristic and predictable EEG activities for later functional disorders of ELBWI. doi:10.1016/j.clinph.2009.02.020
15. Learning about advantageous decision-making influences subsequent sleep—Takashi Abe, Yoko Komada, Yuichi Inoue, Tadao Hori (Hiroshima University, Higashi-Hiroshima, Japan) This study was aimed to investigate the relationship between learning of advantageous decision-making and subsequent sleep. Eight healthy volunteers participated in this study (two men and six women, 20–24 years old, mean 21.9 years), and all of them assigned to both learning and control conditions. Polysomnograms were recorded after modified version of Iowa Gambling Task (Bechara et al., 1994) in learning condition and after control task in control condition. The control task was the task which did not need to learn the advantageous choice since the profile of all the choices was same. As a result of comparing the sleep variables of the learning condition and control condition, rapid eye movements (REM) density in learning condition was significantly greater than control condition. Moreover, increased REM density from control condition to learning condition predicted post-sleep increment of the number of choices from advantageous decision-making. This result suggests that offline memory reprocessing about the learning of advantageous decision-making occurs in relation to rapid eye movements in REM sleep. doi:10.1016/j.clinph.2009.02.021
16. Electrical activities during abnormal muscle contractions in a patient with rippling muscle disease—Takakuni Maki, Riki Matsumoto, Takayuki Kondo, Insuk Son, Takahiro Mezaki, Ichizo Nishino, Akio Ikeda, Nobuo Kohara, Ryosuke Takahashi (Kyoto University, Kyoto, Japan) Objective: To determine the electrophysiological trait of rippling muscle disease (RMD). Background: RMD is a myopathy with symptoms and signs of muscular hyperirritability characterized by percussion-induced rapid muscle contractions (PIRCs) and involuntary rolling muscle contractions (muscle rippling) provoked by mechanical stimuli and stretch. Most reports have shown that these abnormal muscle contractions were electrically silent, i.e., no action potentials in electromyogram. However, a few studies were against the notion, and the pathophysiology needs to be clarified by detail electrophysiological investigation. Methods: Subject is a 30-year-old man with RMD diagnosed by a reduced expression of caveolin-3 in the sarcolemma and missense mutation Arg27Gln in a caveolin-3 gene. Abnormal muscle contractions were investigated simultaneously with electromyogram and ultrasound. Results: During muscle rippling of the quadriceps femoris, the ultrasound study revealed rolling muscle contractions not only in superficial parts but also in deep parts. Needle electromyogram of the muscle rippling and PIRCs revealed electrical activities with short duration (<2 ms). The activities were not well recorded with surface electromyogram. This most likely represented single-fiber potentials rather than motor-unit potentials.
Society Proceedings / Clinical Neurophysiology 120 (2009) e147–e180
Conclusions: The existence of electrical activities was demonstrated during abnormal muscle contractions in a patient with genetically-confirmed RMD.
e151
of visual function using VEPs may contribute to prevent postoperative visual dysfunction. doi:10.1016/j.clinph.2009.02.024
doi:10.1016/j.clinph.2009.02.022
17. Inadequate spinal inhibitory control in a patient with Stiffperson syndrome—Hiroshi Morita, Minori Kodaira, Shu-ichi Ikeda (Shinshu University, Matsumoto, Japan) Spinal inhibitory reflexes were studied in a patient with anti-GAD positive Stiff-person syndrome. The extents of conditioning stimulus effects to soleus H-reflexes elicited with tibial nerve stimulation. Common peroneal nerve (CPN) were stimulated to evoke reciprocal Ia and D1 inhibition, and tendon of biceps femoris was mechanically tapped to evoke long lasting presynaptic inhibition (PSI). CPN stimulation elicited no reciprocal Ia inhibition, but short latency low threshold facilitation. The extent of D1 and PSI was smaller than the normal subject. With improvement of symptoms with Rituximab, the size of the maximal H-reflex decreased (before 38 2:5% of Mmax, after 26 2:7; P < 0:001Þ and H/M threshold ratio increased (before 62%, after 80%). The extent of PSI also increased with treatment (before 86 12% of control, after 69 17; P >< 0:05), but other inhibition did not increased significantly. The decrease in abnormal short latency facilitation was not significant (before 134 21% of control, after 122 19%). The impairment of spinal inhibitory system such as presynaptic inhibition is a possible mechanism for muscle stiffness in Stiff-person syndrome. doi:10.1016/j.clinph.2009.02.023
18. Intraoperative estimation of visual function using visual evoked potential—Tatsuya Sasaki 1, Takeshi Itakura 1, Kyouichi Suzuki 2, Yuka Matsumoto 1, Hitoshi Ando 1, Hiromichi Kasuya 1, Hiroyuki Muramatsu 1, Tsuyoshi Ichikawa 1, Taku Sato 1, Jun Sakum 1 (1 Fukushima Medical University, Fukushima, Japan, 2 Fukushima Red Cross Hospital, Fukushima, Japan) Intraoperative estimation of visual function using visual evoked potentials (VEPs) was performed. We developed a new light-stimulating device and recorded electroretinograms (ERGs) to ascertain retinal visual stimulation under total venous anesthesia. Stable ERG and VEP recordings were obtained in 207 of 220 eyes. In 12, ERG was recorded but VEP could not be recorded, probably because of visual dysfunction. The disappearance of ERG and VEP in the 13th eye after frontal scalp–flap reflection suggested technical failure. The criterion for VEP amplitude changes was defined as a 50% increase or decrease. In one of 207 eyes we observed an amplitude increase and functional improvement in vision. In 19 of 188 eyes without VEP changes, visual function improved, while in 167 no functional changes were observed, and in 2 visual function worsened (one patient developed a slight visual field defect in both eyes). In 4 eyes with VEP deterioration and subsequent recovery upon changing the operative maneuver; visual function improved in one and exhibited no change in three. The VEP amplitude decreased without subsequent recovery in 14 eyes; all of these developed various degrees of visual dysfunction. e could record intraoperative VEPs in almost all cases except for patients with severe visual dysfunction. None of patients without a decreased VEP amplitude showed apparent postoperative deterioration in visual function, suggesting that intraoperative estimation
19. Facial nerve motor evoked potential monitoring during microvascular decompression for hemifacial spasm—Masafumi Fukuda, Makoto Oishi, Yukihiko Fujii (University of Niigata, Niigata, Japan) To determine whether monitoring facial nerve motor evoked potentials (FNMEPs) elicited by transcranial electrical stimulation during microvascular decompression for hemifacial spasm (HFS) is useful for predicting postoperative outcome. We analyzed FNMEP findings in 25 patients with HFS. Corkscrew electrodes positioned at C3 or C4 and Cz were used to deliver supramaximal stimuli (152–450 V). FNMEPs were recorded from the orbicularis oculi, mentalis, and orbicularis oris muscles. The post-to-predecompression FNMEP ratios (shown as percentages) were used for analysis. Not only FNMEPs but also lateral spread responses (LSRs) were monitored to confirm complete decompression of the facial nerve. Twenty-four of 25 patients had no symptoms postoperatively. In those patients, LSRs disappeared completely or the LSR amplitude decreased markedly, and the amplitude of the FNMEPs obtained from the orbicularis oculi muscle significantly decreased after decompression ðp < 0:0005Þ. The FNMEP ratio in the orbicularis oculi muscle (44%) was significantly lower than that in the mentalis muscle (96%), or in the orbicularis oris (84%). In the only one patient, who showed no changes in both the LSR and FNMEP waveforms, mild HFS had remained 8 months after surgery. In HFS patients, a reduction in FNMEP amplitude obtained from the orbicularis oculi after microvascular decompression suggests normalization of excitability of the facial nerve. FNMEP monitoring during surgery as well as LSR monitoring can predict postoperative outcome in HFS patients. doi:10.1016/j.clinph.2009.02.025
20. Hybrid assistive neuromuscular dynamic stimulation (HANDS) therapy in patients with chronic stroke—Toshiyuki Fujiwara, Yoshihiro Muraoka, Tetsuya Tsuji, Kimitaka Hase, Yoshihisa Masakado, Akio Kimura, Meigen Liu (Keio University School of Medicine, Tokyo, Japan) We devised a therapeutic approach to facilitate the use of the paretic UE in daily life by combining integrated volitional control electrical stimulation with a wrist splint, the HANDS therapy. The aim of this study is to assess its effects on selected measures of hand function and electrophysiological measurements. Participants were 30 patients with chronic hemiparetic stroke. Before and immediately after 3 weeks of training and wearing the system for 8 h each day, clinical measures of motor impairment, amount of use of paretic hand in ADL, as well as neurophysiological measures including reciprocal inhibition and intracortical inhibition were assessed. The follow-up clinical assessment was performed 3 months later. UE motor function improved after the intervention. The amount of use of the paretic hand in ADL had been increased. The intervention induced restoration of presynaptic and long loop inhibitory connections as well as disynaptic reciprocal inhibition. Paired pulse TMS study indicated disinhibition of the short intracortical inhibition in the affected hemisphere. The follow-up assessment showed that improvements were maintained at 3 months. The HANDS therapy is suggested to