Chikashi Fukaya

Nihon University, Edo, Tōkyō, Japan

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Publications (97)136.51 Total impact

  • Chikashi Fukaya, Takamitsu Yamamoto
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    ABSTRACT: We conducted a systematic review to assess the incidence of various surgical complications both during and after stereotactic and functional neurosurgery. Initially, we considered that surgical complications and the adverse effects of stimulation should be differentiated. In some reports, intracranial hemorrhage, infection, device-related problems, and epileptic seizure have been regarded as major and serious surgical complications. The established rates of hemorrhagic complications are 3.7%[95% confidence interval(CI):2.8-4.6%]for coagulation surgery and 4.6%(95% CI:3.8-5.3%)for deep brain stimulation(DBS). However, the rates of significant permanent neurological deficits originating from hemorrhage were relatively low. The average rates were 1.2%(95% CI:0.7-1.6%)for coagulation surgery and 1.0%(95% CI:0.6-1.3%)for DBS. Almost all of the patients with infectious complications had undergone DBS, and these complications were very rarely encountered after coagulation surgery. The rate of the occurrence of infection in DBS patients was 4.0%(95% CI:3.5-4.5%). Device-related problems were complications of DBS, and the main problems were migration and fracture. Epileptic seizure was noted in 0.4%(95% CI:0.1-0.7%)of the patients who underwent coagulation surgery and in 3.2%(95% CI:2.3-4.0%)of those who underwent DBS. The actual rate of occurrence of epileptic seizure was speculated to be much lower than the above rate because we did not include analytical reports that did not mention epileptic seizure. The exact rate of the occurrence of adverse effects caused by DBS was difficult to determine. Skill in the programming of the stimulation parameters, disease progression, and the balance between drugs and stimulation may affect the postoperative adverse events. However, we can advise patients and their families of the potential for psychiatric symptoms, depression, and cognitive dysfunction, which could seriously infringe on the patient's quality of life, after DBS.
    No shinkei geka. Neurological surgery 08/2014; 42(8):751-68. · 0.13 Impact Factor
  • Takamitsu Yamamoto, Chikashi Fukaya, Atsuo Yoshino
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    ABSTRACT: Development of instruments for spinal cord stimulation is remarkable. We can implant two cylinder-type stimulation electrodes in parallel into the spinal epidural space. We call this method for dual-lead SCS. Dual lead-SCS is useful to induce paresthesia over the painful area, and the success rate of pain reduction induced by dual-lead SCS is increasing. For dual-lead stimulation, the RestoreSensor, the EonMini, and the Precision Plus are suitable and useful for the treatment of intractable pain. Based on the results of a drug-challenge test with ketamine, we applied dual-SCS for the treatment of various kinds of neuropathic pain. Comparing with the results of single-lead SCS, dual-lead SCS has obvious advantages to evoke paresthesia over the painful area, and showed a remarkable effects for pain reduction. Dual-lead SCS combined with low-dose ketamine drip infusion method is useful for the treatment of various kinds of neuropathic pain. Even if the direct effect of ketamine is transient, effects that provide release from central sensitization and the wind-up phenomenon may be important to increase the effects of dual-lead SCS. Based on the development of dual-lead SCS, SCS therapy has become an important and powerful method for the treatment of intractable pain.
    Masui. The Japanese journal of anesthesiology 07/2014; 63(7):775-82.
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    ABSTRACT: Object Holmes' tremor (HT) is generally considered to be a symptomatic tremor associated with lesions of the cerebellum, midbrain, or thalamus. Deep brain stimulation (DBS) therapy for essential tremor and parkinsonian tremor has proved quite successful. In contrast, surgical treatment outcomes for HT have often been disappointing. The use of 2 ipsilateral DBS electrodes implanted in parallel within the thalamus for severe essential tremor has been reported. Since dual-lead stimulation within a single target can cover a wider area than single-lead stimulation, it produces greater effects. On the other hand, DBS of the subthalamic area (SA) was recently reported to be effective for refractory tremor. Methods The authors implanted 2 DBS electrodes (one at the nucleus ventralis oralis/nucleus ventralis intermedius and the other at the SA) in 4 patients with HT. For more than 2 years after implantation, each patient's tremor was evaluated using a tremor rating scale under the following 4 conditions of stimulation: "on" for both thalamus and SA DBS; "off" for both thalamus and SA DBS; "on" for thalamus and "off" for SA DBS; and "on" for SA and "off" for thalamus DBS. Results The tremor in all patients was improved for more than 2 years (mean 25.8 ± 3.5 months). Stimulation with 2 electrodes exerted greater effect on the tremor than did 1-electrode stimulation. Interestingly, in all patients progressive effects were observed, and in one patient treated with DBS for 1 year, tremor did not appear even while stimulation was temporarily switched off, suggesting irreversible improvement effects. The presence of both resting and intentional/action tremor implies combined destruction of the pallidothalamic and cerebellothalamic pathways in HT. A larger stimulation area may thus be required for HT patients. Multitarget, dual-lead stimulation permits coverage of the wide area needed to suppress the tremor without adverse effects of stimulation. Some reorganization of the neural network may be involved in the development of HT because the tremor appears several months after the primary insult. The mechanism underlying the absence of tremor while stimulation was temporarily off remains unclear, but the DBS may have normalized the abnormal neural network. Conclusions The authors successfully treated patients with severe HT by using dual-electrode DBS over a long period. Such DBS may offer an effective and safe treatment modality for intractable HT.
    Journal of Neurosurgery 03/2014; DOI:10.3171/2014.1.JNS12392 · 3.15 Impact Factor
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    ABSTRACT: A 62-year-old man complained of resting tremor and posture tremor. In spite of presence of the tremor, other parkinsonian component was very mild. [(11)C]2β-carbomethoxy-3β-(4-fluorophenyl)-tropane ([(11)C]CFT) PET showed asymmetrical reduction of the uptake and [(11)C]raclopride PET showed slightly increased uptake in the striatum. Although he was diagnosed as having benign tremulous parkinsonism (BTP), anti-parkinsonian medications, including anti-cholinergic agent, dopamine agonist and l-dopa, were not effective for his tremor. His tremor gradually deteriorated enough to disturb writing, working, and eating. Because his quality of life (QOL) was disturbed by the troublesome tremor, deep brain stimulation of the subthalamic nucleus (STN-DBS) was performed. After STN-DBS, his tremor was dramatically improved. According to clinical course of our patient as well as previous reports, STN-DBS should be considered as a therapeutic option for BTP patients with severe tremor.
    Rinsho shinkeigaku = Clinical neurology 01/2014; 54(6):511-4. DOI:10.5692/clinicalneurol.54.511
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    ABSTRACT: Background: Vegetative state (VS) is a complex condition that represents a challenging frontier for medicine and neuroscience research. Nowadays there is no scientifically validated treatment for VS patients, and their chronic long-term assistance is very demanding for healthcare systems worldwide. Objectives: The present paper is a systematic review of the role of spinal cord stimulation (SCS) as a treatment of patients with VS. Methods: Published literature on this topic was analyzed systematically. Clinical and epidemiological characteristics of VS, present therapeutic options and social costs of VS were also evaluated. Results: Only 10 papers have been published since 1988, and overall 308 VS patients have been treated with SCS worldwide; 51.6% displayed a clinical improvement and an amelioration of the environmental interaction. These effects are probably mediated by the stimulation of the reticular formation-thalamus-cortex pathway and by cerebral blood flow augmentation induced by SCS. Conclusions: The experience on this topic is still very limited, and on this basis it is still hard to make any rigorous assessment. However, the most recent experiments represent significant progress in the research on this topic and display SCS as a possible therapeutic tool in the treatment of VS.
    Stereotactic and Functional Neurosurgery 06/2013; 91(5):275-287. DOI:10.1159/000348271 · 1.48 Impact Factor
  • Japanese Journal of Neurosurgery 01/2013; 22(3):200-206. DOI:10.7887/jcns.22.200
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    ABSTRACT: OBJECTIVE: High-intensity and high-frequency repetitive transcranial magnetic stimulation (rTMS) of the primary motor cortex was carried out in poststroke patients with increased spasticity, and the changes in F-wave parameters in comparison with M-wave parameters induced by rTMS were examined. METHODS: Ten-hertz rTMS pulses were delivered to the primary motor cortex of the lesion side at 110% intensity of the resting motor threshold, and F-waves were obtained from the first dorsal interosseous muscle. F-waves were recorded before (pre-stim) and immediately after the end of rTMS (post-stim) in poststroke patients. RESULTS: F-wave persistence and F/M Amp.Ratio increased significantly in patients with lesions in upper motor tract as compared with healthy subjects (Wilcoxon rank sum test, p = 0.00023 and p = 0.0073, respectively). After the rTMS application, both F-wave persistence and F/M Amp.Ratio decreased significantly (paired t-test, p = 0.0095 and p = 0.037, respectively). However, the F-wave amplitude did not show a statistically significant variance in poststroke patients. CONCLUSIONS: High-frequency suprathreshold rTMS may suppress the F-waves by enhancing the inhibitory effect on spinal excitability through the corticospinal tract, and F-wave persistence and F/M Amp.Ratio can be used to determine the effect of rTMS on patients with increased spasticity.
    Neuromodulation 10/2012; 16(3). DOI:10.1111/j.1525-1403.2012.00520.x · 1.79 Impact Factor
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    ABSTRACT: OBJECTIVES: Intention tremor becomes evident only when patients intend to move their body and is characterized by dysmetria. We have developed an on-demand control system that triggers the switching on/off of deep brain stimulation (DBS) instantly for the control of intention tremor. MATERIAL AND METHODS: We used surface electrodes for the recording of electromyographic (EMG) activity, and the power of EMG activity was analyzed instantly employing the fast Fourier transform. The on-demand control system switched on DBS when only the power of tremor frequency exceeded the on-trigger threshold, and the system switched off DBS when the total power of EMG activity decreased below the off-trigger threshold. RESULTS: The on-demand control system triggered the switching on/off of DBS accurately, and controlled intention tremor completely. Our on-demand control system is small and portable, and suitable for clinical use. CONCLUSIONS: The on-demand control system for DBS is useful for controlling intention tremor and may decrease the incidence of tolerance to DBS and may be a powerful tool for various applications of neuromodulation therapy.
    Neuromodulation 10/2012; 16(3). DOI:10.1111/j.1525-1403.2012.00521.x · 1.79 Impact Factor
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    ABSTRACT: Objectives Intracranial hemorrhage is a crucial complication of deep brain stimulation (DBS) surgery. The bleeding caused by mechanical tissue injury due to microelectrode and/or DBS electrode lead insertion has been well studied. However, hemorrhage caused by a congenital underlying disease such as vascular malformation has not been examined carefully. Materials and Methods We encountered a case of intracerebral hemorrhage from arteriovenous malformation (AVM) after DBS surgery. Preoperative magnetic resonance (MR) imaging did not show any abnormality in the patient. Computed tomography (CT) images taken immediately after the surgery did not show any intracranial hematoma and other abnormal findings. However, the patient did not recover from the general anesthesia, and hemorrhage in the left occipital lobe was detected by CT performed a day after the surgery. The location of the hematoma was markedly distant from the trajectory of DBS leads. Evacuation of the hematoma under general anesthesia was immediately performed. ResultsAs an intraoperative finding, we noted the presence of abnormal vessels inside the hematoma in the occipital lobe. Tissue specimens including the abnormal vessels were obtained for histopathological analysis, results of which led to the diagnosis was AVM. Conclusion Despite its low incidence, we would like to advise that such a type of hemorrhage could occur and measures should be taken to prevent its occurrence as much as possible. Preoperative detection of abnormal vessels by MR angiography and/or CT angiography might be helpful. Moreover, paying close attention to the possible leakage of cerebrospinal fluid during surgery might be important.
    Neuromodulation 10/2012; 16(5). DOI:10.1111/j.1525-1403.2012.00516.x · 1.79 Impact Factor
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    ABSTRACT: Autonomic nervous system impairment is an untoward symptom that is typically observed in advanced Parkinson's disease (PD) patients. However, details of the effects of subthalamic nucleus deep brain stimulation (STN-DBS) on the autonomic nervous system remain unclear. Twenty-eight patients with advanced PD (12 males and 16 females) who underwent bilateral STN-DBS and 13 age-matched healthy controls were included in this study. We analyzed the dynamic cardiovascular autonomic function regulating the R-R interval and blood pressure by spectral and transfer function analyses of cardiovascular variability before and after STN-DBS. Vagally mediated arterial-cardiac baroreflex function improved after STN-DBS compared to that before STN-DBS (p < 0.05). However, there were no statistically significant differences in the results of the comparison of vagally mediated arterial-cardiac baroreflex function between on-stimulation and off-stimulation. The vagal component in cardiac autonomic dysfunction associated with PD is expected to improve after STN-DBS. We considered that the patients improved their lifestyle; in particular, increasing the amount of exercise by STN-DBS and the best pharmachological treatment may have positive effects on parasympathetic activities.
    Stereotactic and Functional Neurosurgery 06/2012; 90(4):248-54. DOI:10.1159/000338090 · 1.48 Impact Factor
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    ABSTRACT: Background and Objective:  Deep brain stimulation (DBS) candidates with neurologic diseases such as unruptured aneurysm present additional challenges to neurosurgeons when craniotomy must precede DBS surgery. Such craniotomy may potentially overlap with intended burr hole sites for the later insertion of DBS electrodes, and the skin incision for craniotomy may lie very close to or intersect with that for the burr holes. We report here a case of forehead craniotomy prior to DBS surgery in which we employed a neuronavigation system to simulate locations for the craniotomy and burr holes. Method:  A 62-year-old male patient with Parkinson's disease was a candidate for DBS. He also had an aneurysm and was planned first to undergo frontal craniotomy for clipping before the DBS surgery. The locations of the craniotomy, burr holes, and skin incisions were therefore simulated using a neuronavigation system during craniotomy. Results:  Two weeks after the craniotomy, the patient underwent DBS surgery. Planning software confirmed the absence of cortical veins beneath the entry points of tentative burr holes and aided trajectory planning. The DBS surgery was performed without the interference of the burr holes and head pins and the craniotomy. Conclusion:  Simulation of the locations of craniotomy and burr holes using a neuronavigation system proved valuable in the present case of frontal craniotomy before DBS surgery.
    Neuromodulation 06/2012; 16(1). DOI:10.1111/j.1525-1403.2012.00466.x · 1.79 Impact Factor
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    ABSTRACT: OBJECTIVE: On the basis of the findings of the electrophysiological evaluation of vegetative state (VS) and minimally conscious state (MCS), the effect of deep brain stimulation (DBS) was examined according to long-term follow-up results. The results of spinal cord stimulation (SCS) on MCS was also examined and compared with that of DBS. METHODS: One hundred seven patients in VS and 21 patients in MCS were evaluated neurologically and electrophysiologically over 3 months after the onset of brain injury. Among the 107 VS patients, 21 were treated by DBS. Among the 21 MCS patients, 5 were treated by DBS and 10 by SCS. RESULTS: Eight of the 21 patients recovered from VS and were able to follow verbal instructions. These eight patients showed desynchronization on continuous electroencephalographic frequency analysis. The Vth wave of the auditory brainstem response and N20 of somatosensory evoked potential were recorded even with a prolonged latency, and pain-related P250 was recorded with an amplitude of more than 7 μV. In addition, DBS and SCS induced a marked functional recovery in MCS patients who satisfied the electrophysiological inclusion criteria. CONCLUSION: DBS for VS and MCS patients and SCS for MCS patients may be useful, when the candidates are selected on the basis of the electrophysiological inclusion criteria. Only 16 (14.9%) of the 107 VS patients and 15 (71.4%) of the 21 MCS patients satisfied the electrophysiological inclusion criteria.
    World Neurosurgery 04/2012; 80(3-4). DOI:10.1016/j.wneu.2012.04.010 · 2.42 Impact Factor
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    ABSTRACT: It is obvious that deep brain stimulation (DBS) is one of the useful treatment choices for progressive Parkinson disease (PD). The main targets for DBS for PD are the thalamic Vim nucleus, globus pallidus interna (GPi), and subthalamic nucleus (STN). Vim-DBS is useful for tremor but not very effective for other Parkinson symptoms. Therefore, presently, STN and GPi are the common targets for DBS for PD. Diminishing the dose of anti-PD drugs is possible usually only after STN-DBS. However, no evident differences in the effect between STN-DBS and GPi-DBS are noted in the majority of studies. Appropriate indication should be decided on the basis of individual target's feature. Dopa responsiveness is a very important factor when considering the operative indications for both STN-DBS and GPi-DBS. CAPSIT protocol is usually used to evaluate the dopa responsiveness. DBS is considered to be characterized by the bottom-up and substitution effects. The disappearance of wearing-off is expected owing to the bottom-up effect and the disappearance of the side effects of anti-PD drugs is expected owing to the substitution effect. Age at surgery, duration of PD, and degree of dopa responsiveness are important factors for outcome prediction. On the other hand, the rate of complications such as cognitive decline, psychosis, and intracranial hemorrhage is relatively high in elderly patients.
    01/2012; 52(11):1095-7. DOI:10.5692/clinicalneurol.52.1095
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    ABSTRACT: Minimally conscious state (MCS) is characterized by inconsistent but clearly discernible behavioral evidence of consciousness, and can be distinguished from coma and the vegetative state (VS). Ten MCS patients were evaluated neurologically and electrophysiologically over 3 months after the onset of brain injury, and were treated by spinal cord stimulation (SCS). A flexible four-contact, cylinder electrode was inserted into the epidural space of the cervical vertebrae, and placed at the C2-C4 levels. Stimulation was applied for 5 minutes every 30 minutes during the daytime at an intensity that produced motor twitches of the upper extremities. We used 5 Hz for SCS, considering that the induced muscle twitches can be a useful functional neurorehabilitation for MCS patients. Eight of the 10 MCS patients satisfied the electrophysiological inclusion criteria, which we proposed on the basis of the results of deep brain stimulation for the treatment of patients in the VS. Seven patients recovered from MCS following SCS therapy, and were able to carry out functional interactive communication and/or demonstrate the functional use of two different objects. Cervical SCS increased cerebral blood flow (CBF) diffusely in the brain, and CBF increased by 22.2% during the stimulation period compared with CBF before stimulation in MCS patients (p < 0.0001, paired t-test). Five-Hz cervical SCS could increase CBF and induce muscle twitches of the upper extremities. This SCS therapy method may be suitable for treating MCS.
    Neurologia medico-chirurgica 01/2012; 52(7):475-81. DOI:10.2176/nmc.52.475 · 0.65 Impact Factor
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    ABSTRACT: In well-designed multicenter studies, the protocol of continuing motor cortex stimulation (MCS) temporarily for 3-6 weeks was employed with rehabilitation therapy, and these studies showed some recovery of motor weakness in post-stroke patients. We aimed to clarify the effects of long-term MCS and the optimal stimulation conditions to improve motor weakness in post-stroke patients. We applied chronic MCS in 6 post-stroke pain patients with motor weakness. We then examined the correlation between the duration of daily MCS applied over 6 months and motor function assessed on the basis of the Fugl-Meyer Assessment (FMA) score of the patients. In the 6 patients with motor weakness, the FMA score of the upper extremity increased in 4 patients who underwent daily MCS for less than 4 h. On the other hand, 2 patients who continued excessive MCS to control their complicating post-stroke pain showed decreased FMA scores and worsened motor function owing to their increased rigidity and/or spasticity. These 2 patients recovered their motor function after their daily MCS was restricted to less than 4 h. These findings indicate that MCS could be a new therapeutic approach to improving motor performance after stroke by attenuating rigidity and/or spasticity. However, it may be important to define the appropriate number of hours and conditions of daily MCS.
    Stereotactic and Functional Neurosurgery 11/2011; 89(6):381-9. DOI:10.1159/000332060 · 1.48 Impact Factor
  • No shinkei geka. Neurological surgery 11/2011; 39(11):1033-44. · 0.13 Impact Factor
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    ABSTRACT: The objective of this study was to evaluate the efficacy of chronic subthalamic nucleus (STN) stimulation for alleviating pain related to Parkinson disease (PD). Among 163 consecutive patients undergoing STN stimulation, 69 were identified as experiencing pain preoperatively that was related to their PD. All 69 patients suffering from pain were followed up prospectively for 12 months after surgery. All patients described the severity of their pain according to a visual analog scale (VAS) preoperatively and at 2 weeks, 6 months, and 12 months postoperatively. Pain unrelated to PD was not studied. Several types of pain related to PD, the categories of which were based on a modification of 2 previous classifications (Ford and Honey), can occur in such patients: 1) musculoskeletal pain, 2) dystonic pain, 3) somatic pain exacerbated by PD, 4) radicular/peripheral neuropathic pain, and 5) central pain. The overall mean VAS score was significantly decreased postoperatively by 75% and 69% at 2 weeks and 6 months, respectively (p < 0.001). The mean VAS score at 12 months was also decreased by 80%, but 6 instances of pain (3 reports of somatic back pain and 3 reports of radicular/peripheral neuropathic pain) required additional spinal surgery to alleviate the pain severity. The results were analyzed using the Wilcoxon signed-rank test and demonstrated a significant reduction in VAS scores at all follow-up assessments (p < 0.001). Musculoskeletal pain and dystonic pain were well alleviated by STN stimulation. In contrast, somatic pain exacerbated by PD and peripheral neuropathic pain originating from lumbar spinal diseases, such as spondylosis deformans and/or canal stenosis, often deteriorated postoperatively despite attenuation of the patients' motor disability. Patients with central pain were poor responders. This study found that STN stimulation produced significant improvement of overall pain related to PD in patients with advanced PD, and the efficacy continued for at least 1 year. The present results indicate that musculoskeletal pain and dystonic pain responded well to STN stimulation, but patients with back pain (somatic pain) and radicular/peripheral neuropathic pain originating from spinal disease have a potential risk for postoperative deterioration of their pain.
    Journal of Neurosurgery 09/2011; 116(1):99-106. DOI:10.3171/2011.7.JNS11158 · 3.15 Impact Factor
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    ABSTRACT: Recent studies have indicated the importance of subcortical mapping of the corticospinal tract (CT) during tumor resection close to the primary motor area. It is substantial evidence that the corticospinal descending direct wave (D-wave) can be used as a guide for mapping of the primary motor cortex (M1) and for monitoring of the CT functional integrity. In the present study, the authors investigated the feasibility of D-wave recordings after subcortical stimulation. The authors examined 14 patients with brain tumors close to the M1 and/or CT, who exhibited no obvious motor deficit before surgery. Subcortical white matter was electrically stimulated in monopolar or bipolar fashion by recording the descending wave (D-wave) from the spinal epidural space using a catheter-type electrode. Subcortical D-wave was more clearly recorded after monopolar stimulation than after bipolar stimulation. The features of the subcortical D-wave, including its waveform, conduction velocity, and latency, were nearly identical to those of the corticospinal D-wave recorded after M1 stimulation. Subcortical D-wave amplitude was prone to change depending on the distance from the stimulation points to the CT. Changes in parameters of subcortical D-wave may provide valuable information to prevent postoperative motor deficit. Further studies are required to clarify the relationship between the distance from the stimulating point to the CT and the amplitude of the subcortically elicited D-wave.
    Journal of clinical neurophysiology: official publication of the American Electroencephalographic Society 06/2011; 28(3):297-301. DOI:10.1097/WNP.0b013e31821c2fc3 · 1.60 Impact Factor
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    ABSTRACT: Movement disorders associated with cerebral cavernous malformations (CM) are seldom reported, and chorea, in particular, is rarely associated with a CM located in the caudate nucleus. Here we report a 78-year-old female patient with chorea, who presented with choreiform movements due to a CM in the contralateral caudate nucleus. A brain MRI was obtained and compared with that obtained before the onset of chorea. The new images did not reveal further extralesional hemorrhage from the CM when compared with the previous images. The choreiform movements showed spontaneous improvement and then disappeared completely. We reviewed previous reports of patients with chorea associated with a CM, and conclude that CM located in the caudate nucleus can cause chorea.
    Journal of Clinical Neuroscience 03/2011; 18(5):719-21. DOI:10.1016/j.jocn.2010.08.034 · 1.32 Impact Factor
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    ABSTRACT: Motor cortex stimulation (MCS) is a treatment option for various disorders such as medically refractory pain, poststroke hemiplegia, and movement disorders. However, the exact mechanisms underlying its effects remain unknown. In this study, the effects of long-term chronic MCS were investigated by observing changes in astrocytes. A quadripolar stimulation electrode was implanted on the dura over the sensorimotor cortex of adult rats, and the cortex was continuously stimulated for 3 hours, 1 week, 4 weeks, and 8 weeks. Immunohistochemical staining of microglia (ionized calcium-binding adaptor molecule 1 [Iba1] staining) and astrocytes (glial fibrillary acidic protein [GFAP] staining), and neuronal degeneration histochemistry (Fluoro-Jade B staining) were carried out to investigate the morphological changes following long-term chronic MCS. Iba1 staining and Fluoro-Jade B staining showed no evidence of Iba1-positive microglial changes or neurodegeneration. Following continuous MCS, GFAP-positive astrocytes were enlarged and their number increased in the cortex and the thalamus of the stimulated hemisphere. These findings indicate that chronic electrical stimulation can continuously activate astrocytes and result in morphological and quantitative changes. These changes may be involved in the mechanisms underlying the neuroplasticity effect induced by MCS.
    Neurologia medico-chirurgica 01/2011; 51(7):496-502. DOI:10.2176/nmc.51.496 · 0.65 Impact Factor