Successful Management of Acute Subdural Hematoma in Deep Brain Stimulation Patient: A Case Report and Literature Review.

Deep brain stimulation (DBS) has emerged as an important therapeutic option for several movement disorders; however, the management of acute complications, such as acute subdural hematoma (ASDH), remains challenging. This is the case of a 71-year-old woman with Parkinson's disease who developed ASDH 12 years after bilateral DBS placement. On admission with altered consciousness, imaging revealed significant displacement of the DBS electrodes because of the hematoma. Emergent craniotomy with endoscopic evacuation was performed with preservation of the DBS system. Postoperatively, complete evacuation of the hematoma was confirmed, and the patient experienced significant clinical improvement. ASDH causes significant electrode displacement in patients undergoing DBS. After hematoma evacuation, the electrodes were observed to return to their proper position, and the patient exhibited a favorable clinical response to stimulation. To preserve the DBS electrodes, endoscopic hematoma evacuation via a small craniotomy may be useful.

Distinguishing Cerebral Infarction With Neck Pain and Hemiparesis From Cervical Spinal Epidural Hematoma Without MRI: A Case Report.

In patients presenting neck pain and hemiparesis, differentiation between cerebral infarction and cervical spinal epidural hematoma is vital yet challenging, particularly when magnetic resonance imaging (MRI) is not feasible. A 59-year-old woman presented with a sudden onset of left-sided hemiparesis and neck pain. MRI was contraindicated because the patient underwent embolization in childhood. Head computed tomography (CT) revealed no evidence of hemorrhage or early ischemic signs. Cervical CT revealed no evidence of hematoma within the spinal canal. Myelography and CT myelography revealed no significant cervical spine abnormalities. The diagnosis was cerebral infarction. Cervical spine MRI is the gold standard examination for diagnosing cervical spinal epidural hematoma, but cervical spine CT, myelography, and CT myelography may be useful when MRI is contraindicated.

Pallidal deep brain stimulation for patients with myoclonus-dystonia without SGCE mutations.

BACKGROUND: Pallidal deep brain stimulation (GPi-DBS) is effective for treating myoclonus and dystonia caused by SGCE mutations (DYT-SGCE, DYT11). However, it is unknown whether GPi-DBS is effective for the treatment of myoclonus-dystonia which is not associated with the SGCE gene mutations. In this study, we investigated the efficacy of GPi-DBS in treating myoclonus-dystonia in SGCE mutation-negative cases. METHODS: Three patients with myoclonus-dystonia without SGCE mutations who underwent GPi-DBS were evaluated preoperatively and 6 months postoperatively using the Unified Myoclonus Rating Scale (UMRS) and Fahn-Marsden Dystonia Rating Scale (FMDRS) for myoclonus and dystonia, respectively. In two of the three patients, myoclonus was more evident during action. Myoclonus was predominant at rest in the other patient, and he was unaware of his dystonia symptoms. The results were compared with those of the four DYT-SGCE cases. RESULTS: The mean UMRS score in patients with myoclonus-dystonia without SGCE mutations improved from 61.7 to 33.7 pre- and postoperatively, respectively, and the mean FMDRS score improved from 7.2 to 4.5. However, the degree of improvement in myoclonus-dystonia in patients without SGCE mutations was inferior to that in patients with DYT-SGCE (the UMRS score improved by 45% and 69%, respectively). CONCLUSIONS: GPi-DBS is effective for treating myoclonus-dystonia in patients with and without SGCE mutations. GPi-DBS should be considered as a treatment option for myoclonus-dystonia without SGCE mutations.

Sacral myolipoma with involuntary contraction causing tethered cord syndrome: illustrative case.

BACKGROUND: Spinal lipomas sometimes involve various ectopic tissues originating from the ectoderm, mesoderm, and endoderm in the process of morphological development. OBSERVATIONS: A 29-year-old male patient with myolipoma of the conus medullaris at the S2 and S3 levels was described. The unusual finding, involuntary muscle contraction, was presented in an operative video and a literature review. In the present case, sacral myolipoma with involuntary contraction caused tethered cord syndrome in adulthood, and untethering surgery resolved continuous buttock and leg pain. LESSONS: This rare finding is considered a surgical indication for adult patients with myolipoma.

Benefit of spinal cord stimulation for patients with central poststroke pain: a retrospective multicenter study.

OBJECTIVE: Spinal cord stimulation (SCS) has been considered an ineffective procedure for patients with central poststroke pain (CPSP). However, recent case series that included small numbers of patients reported the possible efficacy of SCS as a treatment of CPSP. This multicenter retrospective study aimed to examine the outcomes of using SCS to treat patients with CPSP and to explore factors related to outcomes. METHODS: The authors reviewed the medical records of patients with CPSP who underwent SCS to collect data regarding their background, surgical information, and outcomes of SCS at trial stimulation and last follow-up after long-term implantation in six study centers. Outcomes were evaluated with a pain score for intensity (range 0-10) and the Patient Global Impression of Changes (PGIC) scale. Factors associated with outcomes were explored with univariable and multivariable analyses. RESULTS: The authors collected data from a total of 166 patients (mean age 63.4 years; mean pain score at baseline 8.2). Of these patients, 163 underwent trial stimulation. The mean pain score decreased by 42.0%, 104 (64%) patients had ≥ 30% decrease in pain score, and 96 (59%) reported much or very much improved condition on the PGIC scale at trial stimulation. Moreover, 106 (64%) patients underwent long-term implantation of SCS devices. The mean decrease in pain score was 41.4%, 63 (59%) patients continued to show ≥ 30% decrease in pain score at last follow-up, and 60 (56%) reported much or very much improved condition on the PGIC scale at last follow-up (median [range] follow-up period 24 [24-63] months). Eleven device-related complications and 10 permanent explantations were observed. Univariable and multivariable analyses suggested that young age, less sensory disturbance, implantation of cervical leads, treatment of upper-limb pain, and extensive treated regions were associated with satisfactory outcomes at last follow-up after long-term implantation. CONCLUSIONS: These findings indicate that SCS may modestly benefit patients with CPSP. SCS has therapeutic potential for patients with intractable CPSP owing to the lower invasiveness of the SCS procedure and refractory nature of CPSP. Nevertheless, trial stimulation is necessary because of the high initial failure rate.

Vagus Nerve Stimulation with Mild Stimulation Intensity Exerts Anti-Inflammatory and Neuroprotective Effects in Parkinson's Disease Model Rats.

BACKGROUND: The major surgical treatment for Parkinson's disease (PD) is deep brain stimulation (DBS), but a less invasive treatment is desired. Vagus nerve stimulation (VNS) is a relatively safe treatment without cerebral invasiveness. In this study, we developed a wireless controllable electrical stimulator to examine the efficacy of VNS on PD model rats. METHODS: Adult female Sprague-Dawley rats underwent placement of a cuff-type electrode and stimulator on the vagus nerve. Following which, 6-hydroxydopamine (6-OHDA) was administered into the left striatum to prepare a PD model. VNS was started immediately after 6-OHDA administration and continued for 14 days. We evaluated the therapeutic effects of VNS with behavioral and immunohistochemical outcome assays under different stimulation intensity (0.1, 0.25, 0.5 and 1 mA). RESULTS: VNS with 0.25-0.5 mA intensity remarkably improved behavioral impairment, preserved dopamine neurons, reduced inflammatory glial cells, and increased noradrenergic neurons. On the other hand, VNS with 0.1 mA and 1 mA intensity did not display significant therapeutic efficacy. CONCLUSIONS: VNS with 0.25-0.5 mA intensity has anti-inflammatory and neuroprotective effects on PD model rats induced by 6-OHDA administration. In addition, we were able to confirm the practicality and effectiveness of the new experimental device.

Single arm prospective multicenter case series on the use of burst stimulation to improve pain and motor symptoms in Parkinson's disease.

BACKGROUND: In this study we analyze new clinical data in the use of spinal cord stimulation (SCS) for the treatment of pain and motor symptoms in patients with Parkinson's Disease (PD), as both a singular bioelectric therapy and as a salvage therapy after deep brain stimulation (DBS). METHODS: Fifteen patients were recruited and had percutaneous electrodes implanted at the level of the thoracic or cervical spine. Participants were set to one of three stimulation modes: continuous tonic stimulation, continuous Burst stimulation (40 Hz, 500 Hz, 1000 µs), or cycle mode (on time of 10-15 s, off time of 15-30 s) with Burst (40 Hz, 500 Hz, 1000 µs). Patients completed the Visual Analogue Scale (VAS), Unified Parkinson's Disease Rating Scale, Self-Rating Depression Scale, Hamilton Depression Rating Scale, Profile of Mood State, 10-meter walking test, and the Timed Up and Go (TUG). RESULTS: All patients experienced significant improvement in VAS scores with a mean reduction of 59% across all patients. Patients who chose the cycling burst stimulation parameter had an average 67% reduction in VAS scores, as compared to the continuous burst parameter group, which had an average 48% reduction in VAS scores. Seventy-three percent of patients experienced improvement in the 10-meter walk, with an average improvement of 12%. Sixty-four percent of patients experienced clinically relevant improvements in the TUG, with an average improvement of 21%. CONCLUSIONS: This study points to the potential utility of SCS to address both pain and certain aspects of motor symptoms in PD patients who have and have not received DBS therapy.

Identification of Somatotopic Organization and Optimal Stimulation Site Within the Subthalamic Nucleus for Parkinson's Disease.

BACKGROUND: Details of the somatotopy within the subthalamic nucleus (STN) are still poorly understood; however, the STN is a common target of deep brain stimulation (DBS) for Parkinson disease. OBJECTIVE: To examine somatotopic organization within the STN and identify optimal stimulation sites from 77 surgical cases with microelectrode recording. METHODS: STN-DBS was performed for 77 patients with Parkinson disease between 2010 and 2014. We performed passive movements of each joint and captured single neuronal activities to identify movement-related cells (MRCs). The sites of MRCs and active contacts were determined by measuring their distances from the first contact of DBS electrode. Their positional correlations were directly and indirectly analyzed. RESULTS: The number of obtained MRCs was 264, of which 151 responded to multiple joints. The average x-, y-, and z-coordinates of the cells of the upper and lower limbs from the midcommisural point were 13.1 ± 1.1 and 12.7 ± 1.2, 0.22 ± 1.3 and -0.45 ± 1.5, and -2.5 ± 1.1 and -3.0 ± 1.4 mm, respectively. Most MRCs were distributed in the upper third of the STN, in its superior, lateral, and posterior regions, along the DBS electrode routes. Active contacts were observed to lie slightly inferior, medial, and posterior to the average MRC position. CONCLUSION: Somatotopic organization of the STN was easier to observe in the present study than in previous studies. Optimal stimulation sites were located inferior, medial, and posterior to the average MRC location. The sites may correspond to associative or motor parts through which fibers from the supplementary motor area pass.

Characteristics and prognostic factors of Parkinson's disease patients with abnormal postures subjected to subthalamic nucleus deep brain stimulation.

OBJECTIVE: In Parkinson's disease (PD), abnormal postures are often accompanied, which interfere with rehabilitation and subsequent functional recovery. This study investigated the relationship between clinical characteristics and improvement in abnormal postures of PD patients who received subthalamic nucleus deep brain stimulation (STN-DBS). METHODS: Seventy-four PD patients were included in this study. Clinical data were analyzed using the patients' functional status at pre- and post-STN-DBS, including anteflexion vs. non-anteflexion, scoliosis vs. non-scoliosis, improved anteflexion vs. non-improved anteflexion, and improved scoliosis vs. non-improved scoliosis. RESULTS: In patients with anteflexion, UPDRS III motor score at off medication was worse than that of patients with non-anteflexion. Patients with scoliosis presented with more comorbid spinal deformity and longer disease duration than those without scoliosis. Cobb angle of patients with asymmetrical psoas major and erector spinal muscles was more than that of patients without the asymmetry. Patients with improved anteflexion after STN-DBS had thicker abdominal oblique muscle and transverse abdominal muscle than those of patients without improved anteflexion. Patients with improved scoliosis were significantly younger at PD onset than those without improvement. CONCLUSIONS: There were only a few prognostic factors recognized in patients with improved postures. The thick abdominal muscle for anteflexion and younger PD onset for scoliosis were significant factors for improvement by STN-DBS. Rehabilitation designed to maintain muscle for correct postures may contribute to the amelioration of abnormal postures by STN-DBS, although multicenter trials are needed.

Efficacy of Dural Sealant System for Preventing Brain Shift and Improving Accuracy in Deep Brain Stimulation Surgery.

The success of deep brain stimulation (DBS) depends heavily on surgical accuracy, and brain shift is recognized as a significant factor influencing accuracy. We investigated the factors associated with surgical accuracy and showed the effectiveness of a dural sealant system for preventing brain shift in 32 consecutive cases receiving DBS. Thirty-two patients receiving DBS between March 2014 and May 2015 were included in this study. We employed conventional burr hole techniques for the first 18 cases (Group I) and a dural sealant system (DuraSeal) for the subsequent 14 cases (Group II). We measured gaps between the actual positions of electrodes and the predetermined target positions. We then retrospectively evaluated the factors involved in surgical accuracy. The average gap between an electrode's actual and target positions was 1.55 ± 0.83 mm in all cases. Postoperative subdural air volume e, the only factor associated with surgical accuracy (r = 0.536, P < 0.0001), was significantly smaller in Group II (Group I: 43.9 ± 27.7, Group II: 12.1 ± 12.5 ml, P = 0.0006). The average electrode position gap was also significantly smaller in Group II (Group I: 1.77 ± 0.91, Group II: 1.27 ± 0.59 mm, P = 0.035). Use of a dural sealant system could significantly reduce intracranial air volume, which should improve surgical accuracy.

Electrical Stimulation Enhances Migratory Ability of Transplanted Bone Marrow Stromal Cells in a Rodent Ischemic Stroke Model.

BACKGROUND/AIMS: Bone marrow stromal cells (BMSCs) transplantation is an important strategy for the treatment of ischemic stroke. Currently, there are no effective methods to guide BMSCs toward the targeted site. In this study, we investigated the effect of electrical stimulation on BMSCs migration in an ischemic model of rats. METHODS: Adult male Wistar rats weighing 200 to 250 g received right middle cerebral artery occlusion (MCAO) for 90 minutes. BMSCs (2.5×105 cells/ 4 µl PBS) were stereotaxically injected into the left corpus callosum at 1 day after MCAO. After BMSCs injection, a plate electrode with a diameter of 3 mm connected to an implantable electrical stimulator was placed on the right frontal epidural space and a counter electrode was placed in the extra-cranial space. Electrical stimulation at preset current (100 µA) and frequency (100 Hz) was performed for two weeks. Behavioral tests were performed at 1, 4, 8, and 15 days after MCAO using the modified Neurological Severity Score (mNSS) and cylinder test. Rats were euthanized at 15 days after MCAO for evaluation of infarction area and the migration distance and area of BMSCs found in the brain tissue. After evaluating cell migration, we proceeded to explore the mechanisms guiding these observations. MCAO rats without BMSCs transplantation were stimulated with same current and frequency. At 1 and 2 weeks after MCAO, rats were euthanized to evaluate stromal cell-derived factor 1 alpha (SDF-1α) level of brain tissues in the bilateral cortex and striatum. RESULTS: Behavioral tests at 4, 8, and 15 days after MCAO revealed that stimulation group displayed significant amelioration in mNSS and cylinder test compared to control group (p<0.05). Similarly, the infarction areas of stroke rats in stimulation group were significantly decreased compared to control group (p<0.05). Migration distance and area of transplanted BMSCs were significantly longer and wider respectively in stimulation group. An increased concentration gradient of SDF-1α in stimulation group accompanied this enhanced migration of transplanted cells. CONCLUSIONS: These results suggest that electrical stimulation enhances migratory ability of transplanted BMSCs in ischemic stroke model of rats. If we can direct the implanted BMSCs to the site of interest, it may lead to a greater therapeutic effect.

The Factors Affecting the Difficulty of Percutaneous Cylindrical Electrode Placement for Spinal Cord Stimulation.

OBJECTIVE: Optimal placement of electrodes is important for spinal cord stimulation. Factors affecting the difficulty of percutaneous electrode placement are not well known. In this study, we retrospectively evaluated the factors affecting the difficulty of percutaneous electrode placement. METHODS: We performed a retrospective analysis of 90 consecutive procedures of percutaneous cylindrical electrode implantation at the first author's institution. Age, sex, smoking state, body mass index, the duration of time from the beginning of pain syndrome to operation, diagnosis, the number of previous electrode placements, the previous electrode implantation period, the presence of axial low back pain, the electrode tip level, the pattern of electrode placement, and the reason for reimplantation were selected as factors associated with the success of electrode placement or the operation time of electrode placement. RESULTS: The number of previous electrode placements and the electrode tip level were independently associated with the operation time of electrode placement. According to both univariable and multivariable regression analyses, 1 previous electrode placement lengthened the operation time by approximately 15 minutes. No factors were significantly associated with the success of electrode placement. The more frequently that previous electrode placement was performed, the more difficult electrode placement tended to be. However, electrode reimplantation can be successful given extra time. CONCLUSIONS: This is the first study to evaluate factors affecting the difficulty of percutaneous electrode placement. A history of percutaneous cylindrical electrode placement did not affect the success of current placement, although it lengthened the operation time.

Significance of High-frequency Electrical Brain Activity.

　Electroencephalogram (EEG) data include broadband electrical brain activity ranging from infra-slow bands (< 0.1 Hz) to traditional frequency bands (e.g., the approx. 10 Hz alpha rhythm) to high-frequency bands of up to 500 Hz. High-frequency oscillations (HFOs) including ripple and fast ripple oscillations (80-200 Hz and>200 / 250 Hz, respectively) are particularly of note due to their very close relationship to epileptogenicity, with the possibility that they could function as a surrogate biomarker of epileptogenicity. In contrast, physiological high-frequency activity plays an important role in higher brain functions, and the differentiation between pathological / epileptic and physiological HFOs is a critical issue, especially in epilepsy surgery. HFOs were initially recorded with intracranial electrodes in patients with intractable epilepsy as part of a long-term invasive seizure monitoring study. However, fast oscillations (FOs) in the ripple and gamma bands (40-80 Hz) are now noninvasively detected by scalp EEG and magnetoencephalography, and thus the scope of studies on HFOs /FOs is rapidly expanding.

Hippocampal neurogenesis of Wistar Kyoto rats is congenitally impaired and correlated with stress resistance.

The hippocampus is thought to be an important region for depression. However, the relationship between hippocampal neurogenesis and depression is still controversial. Wistar Kyoto (WKY) rats are frequently used as a depression model. WKY rats are known to show physiologically abnormal features, and these features resemble abnormalities seen in depressed patients. However, the neurogenesis of WKY rats is still unknown. In this study, we first evaluated the neurogenesis of WKY rats and compared it to that of Wistar (WIS) rats. No strain effect was observed in the number of cells positive for 5-bromo-2'-deoxyuridine (BrdU) and BrdU/Doublecortin (Dcx) in the subventricular zone (SVZ). However, the number of BrdU- and BrdU/Dcx-positive cells in the dentate gyrus (DG) of the hippocampus was significantly lower in WKY rats than in WIS rats. Next, we evaluated the correlation between neurogenesis and behavior tests. Behavior tests did not affect neurogenesis in either strain. Hippocampal neurogenesis correlated negatively with the results of a forced swim test (FST) on day 2 in each strain. That is, rats with a lower level of native neurogenesis in the DG showed a higher level of learned helplessness induced by the inescapable stress of the FST on day 1. Our findings indicate that hippocampal neurogenesis in WKY rats is congenitally impaired in contrast to that in WIS rats. Native cell proliferation and neurogenesis in the DG are correlated with stress resistance. These findings may be useful for developing new targets for depression treatment.

Efficacy of Fiber Tractography in the Stereotactic Surgery of the Thalamus for Patients with Essential Tremor.

Several targets and targeting methods are utilized in stereotactic surgery to achieve tremor suppression for patients with intractable tremor. Recent developments in magnetic resonance imaging, including diffusion tensor imaging, have enabled the setting of appropriate targets in stereotactic surgery. In this retrospective study, the optimal target to suppress tremors in stereotactic surgery was explored using diffusion tensor image-based fiber tractography. Four tracts were focused on in this study, namely: the cerebello-thalamo-premotor cortical fiber tract, cerebello-thalamo-primary motor cortical fiber tract, spino-thalamo-somatosensory cortical fiber tract, and pyramidal tract. In 10 patients with essential tremor, we evaluated the thalamotomy lesions and active contacts of the lead in thalamic stimulation by diffusion tensor image-based fiber tractography to reveal which part of the cerebral cortex is most affected by stereotactic surgery. Tremor suppression and adverse events were also evaluated in the patients involved in this study. Consequently, the good tremor suppression was achieved in all patients. There had been no permanent adverse events 3 months after surgery. Twelve lesions in thalamotomy patients or active contacts of the lead in thalamic stimulation patients were on the cerebello-thalamo-premotor cortical fiber tract (12/14 lesions or active contacts: 86%). In conclusion, the cerebello-thalamo-premotor cortical fiber tract may be an optimal target for tremor suppression. Diffusion tensor image-based fiber tractography may enable us to both determine the optimal target to achieve strong tremor suppression and to reduce the number of adverse events by keeping lesions or electrodes away from important fiber tracts, such as the pyramidal tract and spinothalamic fibers.

Complex observation of scalp fast (40-150 Hz) oscillations in West syndrome and related disorders with structural brain pathology.

We investigated the relationship between the scalp distribution of fast (40-150 Hz) oscillations (FOs) and epileptogenic lesions in West syndrome (WS) and related disorders. Subjects were 9 pediatric patients with surgically confirmed structural epileptogenic pathology (age at initial electroencephalogram [EEG] recording: mean 7.1 months, range 1-22 months). The diagnosis was WS in 7 patients, Ohtahara syndrome in 1, and a transitional state from Ohtahara syndrome to WS in the other. In the scalp EEG data of these patients, we conservatively detected FOs, and then examined the distribution of FOs. In five patients, the scalp distribution of FOs was consistent and concordant with the lateralization of cerebral pathology. In another patient, FOs were consistently dominant over the healthy cerebral hemisphere, and the EEG was relatively low in amplitude over the pathological atrophic hemisphere. In the remaining 3 patients, the dominance of FOs was inconsistent and, in 2 of these patients, the epileptogenic hemisphere was reduced in volume, which may result from atrophy or hypoplasia. The correspondence between the scalp distribution of FOs and the epileptogenic lesion should be studied, taking the type of lesion into account. The factors affecting scalp FOs remain to be elucidated.

Perioperative Management Center (PERIO) for Neurosurgical Patients.

Perioperative management is critical for positive neurosurgical outcomes. In order to maintain safe and authentic perioperative management, a perioperative management center (PERIO) was introduced to patients of our Neurosurgery Department beginning in June 2014. PERIO involves a multidisciplinary team consisting of anesthesiologists, dentists/dental hygienists/technicians, nurses, physical therapists, pharmacists, and nutritionists. After neurosurgeons decide on the course of surgery, a preoperative evaluation consisting of blood sampling, electrocardiogram, chest X-ray, and lung function test was performed. The patients then visited the PERIO clinic 7-14 days before surgery. One or two days before surgery, the patients without particular issues enter the hospital and receive a mouth cleaning one day before surgery. After surgery, postoperative support involving eating/swallowing evaluation, rehabilitation, and pain control is provided. The differences in duration from admission to surgery, cancellation of surgery, and postoperative complications between PERIO and non-PERIO groups were examined. Eighty-five patients were enrolled in the PERIO group and 131 patients in the non-PERIO group. The duration from admission to surgery was significantly decreased in the PERIO group (3.6 ± 0.3 days), compared to that in the non-PERIO group (4.7 ± 0.2 days). There was one cancelled surgery in the PERIO group and six in the non-PERIO group. Postoperative complications and the overall hospital stay did not differ between the two groups. The PERIO system decreased the duration from admission to surgery, and it is useful in providing high-quality medical service, although the system should be improved so as not to increase the burden on medical staff.