Risk assessment of lacunar infarct associated with oral conditions: A case control study focused on radiographic bone loss and Eichner classification.

PURPOSE: This study aimed to evaluate whether lacunar infarcts can be predicted from occlusal support and periodontal stage on images. METHODS: Seventy patients with lacunar infarcts and 300 participants without lacunar infarcts who underwent cerebral checkups at our university hospital were retrospectively reviewed. Lacunar infarcts were assessed using magnetic resonance images by a neuroradiologist. The number of teeth, occlusal support, and severity of radiographic bone loss (RBL) were evaluated using computed tomography. Occlusal support was classified according to the Eichner classification. Additionally, patient characteristics were investigated using medical charts and blood test reports. Records of clinical periodontal parameters, such as clinical attachment loss and bleeding on probing, were also evaluated. RESULTS: The severity of RBL and Eichner classification in patients with lacunar infarcts was significantly higher than that in individuals without lacunar infarcts (P<.01). Receiver operating characteristic analysis revealed that the cut-off values for predicting lacunar infarct were ≥ III in the severity of RBL and ≥B1 in the Eichner classification. The corresponding areas under the curve were 0.75 and 0.70, respectively. In multivariate analysis, the factors affecting the severity of RBL (≥ III) (odds ratio [OR], 8.1; 95% confidence interval [CI], 4.1-16.3; P<.001), and Eichner classification (≥B1) (OR, 1.9; 95% CI, 0.86-4.1; P<.05) were significantly associated with the occurrence of lacunar infarcts. CONCLUSION: The severity of RBL and the Eichner classification may be helpful in predicting lacunar infarcts. Therefore, proper periodontal treatment and prosthodontic rehabilitation of missing teeth may prevent lacunar infarcts.

Physiological mechanism of increase in deoxy-hemoglobin concentration during neuronal activation in patients with cerebral ischemia: a simulation study with the balloon model.

Patients with cerebral ischemia or brain tumor have been reported to exhibit an increase of deoxygenated hemoglobin (deoxy-Hb) together with an increase of oxygenated hemoglobin (oxy-Hb). However, the physiological mechanisms underlying this hemodynamic response pattern are unclear. In this study, we performed a simulation using the balloon model (Buxton et al., Magn Reson Med 39:855-864, 1998). We hypothesized that the oxygen extraction rate during the rest period (E 0) in the patients is larger than in normal subjects, because the cerebral blood flow and the speed at which the blood passes through the brain tissues are lower in the patients. The simulation result showed an increase of deoxy-Hb as well as oxy-Hb, especially when E 0 is extremely high. Thus, the results of our simulation suggest that the increase of deoxy-Hb during activation in patients with ischemia or brain tumor is caused by an increased oxygen extraction rate at rest, compared with that of healthy adults.

Monitoring of filter patency during carotid artery stenting using near-infrared spectroscopy with high time-resolution.

We aimed to evaluate the usefulness of a newly developed, near-infrared spectroscopy (NIRS) device for monitoring hemodynamic changes during carotid artery stenting (CAS), as a means to detect filter obstruction due to distal embolism. We evaluated 16 patients with internal carotid artery (ICA) stenosis during the CAS procedure, using a NIRS system that can monitor not only changes in oxygenation of hemoglobin (Hb), but also the fluctuation of oxyhemoglobin (oxy-Hb) synchronized with heartbeat. The NIRS system detected a marked decrease of oxy-Hb and an increase of deoxyhemoglobin (deoxy-Hb) during ICA occlusion in patients without anterior cross circulation (ACC). Patients with ACC showed much smaller changes. The analysis of oxy-Hb fluctuation made it possible to detect occurrence of no-flow in the absence of Hb concentration changes. The amplitude of oxy-Hb fluctuation in the no/slow-flow group was significantly smaller than that in the normal-flow group. Our results indicate that the present high time-resolution NIRS device, which can measure oxy-Hb fluctuation, is superior to conventional NIRS for detecting filter obstruction.

Monitoring of hemodynamic change in patients with carotid artery stenosis during the tilt test using wearable near-infrared spectroscopy.

Transient ischemic attack (TIA) is a major complication in patients with carotid artery stenosis. Patients with severe stenosis sometimes complain of orthostatic dizziness, such as syncope. The purpose of this study was to examine the usefulness of near-infrared spectroscopy (NIRS) for evaluating cerebral circulation in patients with carotid artery stenosis during head-up tilt test (HUTT). Fourteen patients with carotid artery stenosis and nine normal control subjects participated. In addition to blood pressure monitoring, hemoglobin (Hb) values (oxy-Hb, deoxy-Hb, and total Hb) were recorded by a wearable NIRS instrument with a high time resolution during HUTT. Oxy-Hb, which decreased initially when the test table was elevated, subsequently increased in normal volunteers and patients with carotid artery stenosis and did not differ significantly between the two groups. However, the oxy-Hb reduction in the carotid artery stenosis group (-0.02 ± 0.03 a.u.) at 30 s after elevation of the table was significantly larger than in the normal group (0.02 ± 0.02 a.u., P < 0.01). Our results indicate that oxy-Hb reduction in patients with carotid artery stenosis may be related to orthostatic dizziness. We concluded that NIRS monitoring is useful for evaluating cerebral autoregulation in patients with severe carotid artery stenosis.

Endovascular treatment for ruptured vertebral artery dissecting aneurysms at the acute stage.

OBJECTIVE: Ruptured vertebral artery dissecting aneurysms (VADA) should be treated promptly because of the high risk of rebleeding. However, it is difficult to treat dissecting aneurysm during the acute stage using microsurgery because of high intracranial pressure or brain edema. Therefore, endovascular treatment of the ruptured VADA may be a better technique. We retrospectively studied the efficacy and outcome of endovascular treatment of ruptured VADA at the acute stage. METHODS: Ten patients with ruptured VADA received endovascular treatment at the acute stage. Eight patients who had dissecting aneurysms were treated by internal trapping of the dissected segment. We performed stent-assisted coiling (SAC) for a case of VADA in contralateral hypoplastic VA and a case of bilateral dissections, ruptured VADA of the right VA and VA dissection of the left VA. RESULTS: Four patients had good recovery, 3 patients had moderate disability, 2 patients had severe disability, and 1 patient died from initial severe SAH. There was no rebleeding or procedure-related complication. However, one patient who was treated by SAC had ischemic complications post-treatment. CONCLUSION: Endovascular treatment of ruptured VADA in the acute stage appears to be safe and effective.

Comparison between pharmacologic evaluation and repetitive transcranial magnetic stimulation-induced analgesia in poststroke pain patients.

BACKGROUND: It has been reported that poststroke pain has a complex pharmacologic background and that only about one-half of poststroke pain patients are sensitive to motor cortex stimulation induced by repetitive transcranial magnetic stimulation (rTMS). OBJECTIVES: The relationship between pharmacologic background and effects of rTMS of the primary motor cortex was investigated to clarify the pharmacologic basis of rTMS-induced analgesia in poststroke pain patients. METHODS: Changes in visual analog scale (VAS) score for pain following drug challenge tests using ketamine, morphine, and thiopental were compared with the changes in VAS score following rTMS of the primary motor cortex (frequency 5 Hz, at 100% resting motor threshold, 500 pulses per session) in 20 poststroke pain patients. RESULTS: In our drug challenge test, 10 of 20 (50%) patients in ketamine test, 7 of 20 (35%) in thiopental test, and 3 of 20 (15%) in morphine test showed more than 40% reduction of VAS score. VAS score decreased immediately after rTMS of motor cortex and persisted for 300 min (p < 0.05, Bonferroni's multiple comparisons). Comparison of the magnitude of VAS score reduction between drug challenge test and rTMS showed significant correlations with ketamine test (r = 0.503, p = 0.012), morphine test (r = 0.526, p = 0.009), and thiopental test (r = 0.609, p = 0.002) by regression analysis. CONCLUSIONS: rTMS-induced VAS score reduction correlated well with morphine, ketamine, and thiopental tests. However, ketamine sensitivity was observed in more cases compared with morphine and thiopental in poststroke pain patients. We speculate that additional pharmacologic therapy using ketamine as determined on the basis of the ketamine test may be useful for enhancing the efficacy of rTMS in poststroke pain patients.

Effects of occlusal disharmony on working memory performance and prefrontal cortex activity induced by working memory tasks measured by NIRS.

The effects of artificial occlusal disharmony (AOD) on working memory function and prefrontal cortex (PFC) activity in the elderly were examined. We evaluated working memory function using the modified Sternberg test (ST). We measured activity in the bilateral PFC during ST using near-infrared spectroscopy (NIRS) before and after AOD: the mandibular position was displaced by a splint for 10 min. AOD caused a gradual increase of oxyhemoglobin (oxy-Hb) in the bilateral PFC. The response time of ST (six digits) after AOD was longer than that before AOD. The oxy-Hb increase during ST after AOD was smaller than that before AOD. These results indicate that short-term physical stress caused by AOD decreased working memory function in elderly subjects, associated with a decrease of the evoked PFC activity during working memory function.

Pain intensity and psychosocial characteristics of patients with burning mouth syndrome and trigeminal neuralgia.

This study compared pain intensity and psychosocial characteristics between patients with burning mouth syndrome (BMS) and those with trigeminal neuralgia (TN). Data from 282 patients with BMS and 83 patients with TN were analyzed. Patients reported duration of illness: duration ≤ 6 months was defined as acute illness and > 6 months as chronic illness. Present pain intensity and worst pain intensity during the past 6 months were reported using a 0-10 numeric rating scale (NRS). In addition, depression and somatization scores were evaluated on questionnaires. Patients with chronic BMS reported significantly higher pain intensity and had worse psychosocial characteristics than did those with acute BMS. Pain intensity was higher in TN patients than in BMS patients, although neither pain intensity nor psychosocial characteristics significantly differed between patients with acute and chronic illness. Logistic regression analysis of BMS and TN patients revealed that the odds ratio for worst pain was significantly lower for BMS patients than for TN patients and that the odds ratio for somatization score was 3.8 times higher in BMS patients. These findings suggest that BMS patients may require pain control targeting the central nervous system or psychosocial characteristics.

Clivus metastasis from gastric signet ring cell carcinoma after a 10-year disease-free interval--case report.

A 64-year-old male presented with an extremely unusual case of solitary clivus metastasis from gastric cancer manifesting as mild headache and diplopia 10 years after radical excision of the primary tumor. The patient underwent surgical resection using an endoscopic transsphenoidal approach. Histological examination revealed typical signet ring cell carcinoma (SRC) which was identical to that of the previous gastric cancer. Why the late recurrence occurred such a long time after the first surgery and how it spread to the clivus remain unclear. The characteristics of SRC and the process of "tumor dormancy" may have been involved in the mechanism underlying late metastasis.

Is the circulating plasma volume sufficiently maintained? Fluid management of an aneurysmal subarachnoid hemorrhage in the acute phase.

Cerebral vasospasm is a well-known cause of mortality and morbidity following aneurysmal subarachnoid hemorrhage (SAH). Prevention of symptomatic cerebral vasospasm is the basic management after SAH. Numerous pharmaceutical therapies and endovascular treatments are available against cerebral vasospasm, but none of them have so far proven to improve the outcome. We have focused on maintaining the circulation volume in order to prevent cerebral vasospasm. But to maintain the central venous pressure, huge infusion volume was required, and hyponatremia was frequently observed due to natriuresis and osmotic diuresis. Excessive natriuresis and diuresis cannot be managed through sodium and water replacement, since sodium replacement induces further natriuresis and diuresis (desalination), and water replacement induces hyponatremia. We therefore administered fludrocortisone and hydrocortisone to inhibit excessive natriuresis and diuresis. The efficacy of sodium reabsorption therapy is extremely high to maintain the circulation volume that might have a therapeutic effect to prevent cerebral vasospasm. In this article, we review our institution's experience regarding the management of patients with aneurysmal SAH and also discuss the importance of water and sodium balance when managing such patients.

Cost-effectiveness analysis of intrathecal baclofen therapy in Japan.

Intrathecal baclofen (ITB) therapy was approved for health insurance coverage in 2005 for the treatment of patients whose spasticity could not be adequately controlled by conventional therapy, and is currently being used to treat around 300 patients nationwide in Japan. Various reports have examined the efficacy and safety of ITB therapy, but no report has evaluated the patient quality of life and medical costs in Japan. A cost-utility analysis of ITB was conducted by time period in six severely spastic patients admitted to our university hospital between 2005 and 2010 for ITB therapy. The average cost of ITB therapy per quality-adjusted life year (QALY; number of years survival in perfect health) 5 years after surgery was 1,554,428 yen, below the 6 million yen willingness-to-pay threshold for 1 QALY. This study shows that ITB therapy in Japan is an outstanding treatment in medicoeconomic terms.

Medical care for chronic-phase stroke in Japan.

Stroke leaves serious neurological sequelae, which require long-term medical and social care, imposing financial and mental burdens on the patients and their families, and causing enormous losses to society. It is currently required that medical resources be used efficiently and the cost-effectiveness of treatment be analyzed carefully. We conducted a follow-up survey of stroke patients admitted to the hospital attached to our university in order to build a picture of the current status of chronic-phase stroke medical treatment. In total, 330 patients were analyzed in this study. We evaluated utility and medical cost at one year after onset. To investigate the relationship between activities of daily living (ADL) classified according to the modified Rankin scale (mRS) and quality of life (QOL), utility was calculated for each ADL level. Utility at 1 year post-onset for each mRS level was: ADL0, 0.89; ADL1, 0.79; ADL2, 0.65; ADL3, 0.58; ADL4, 0.36; and ADL5, 0.09. A significant correlation was seen between utility and mRS. Direct monthly medical costs at 1 year post-onset were 61,536 yen in the ADL0 group and 383,444 yen in the ADL5 group, indicating that a worse ADL score required higher medical costs. Direct monthly costs were significantly different between ADL levels. This present study has clarified the QOL and medical costs of chronic-phase stroke patients, and many cost-utility analyses will be based on our data in the future in Japan.

[Case of a giant cervical carotid artery aneurysm with contralateral severe stenosis treated using a covered stent].

We report a case of a cervical carotid artery pseudoaneurysm with contralateral severe stenosis, treated using a covered stent. A 79-year-old man admitted for a splenic artery aneurysm presented a pulsatile mass on the right side of his neck and lower cranial nerve palsy after misinsertion of a central venous line into the right carotid artery. MRI revealed a huge thrombosed aneurysm (30 mm×25 mm) in the right common carotid artery (CCA). We planned an aneurysmectomy and CCA interposition with a vascular graft. However the aneurysm continued to expand. We considered that it was difficult to expose the internal carotid artery (ICA) by a direct surgical technique, and therefore carried out placement of a covered stent over the orifice of the aneurysm using an endovascular surgical technique. Following placement of the covered stent, subsequent contrast-enhanced CT revealed leakage of contrast material into the aneurysm. An additional bare stent was placed into the proximal end of the covered stent at 15 days after the initial treatment. Angiography demonstrated no leakage of the contrast material. Following the second treatment, the pulsatile mass was reduced in size. Lower cranial nerve palsy remained but had slightly improved. We described the case of a huge cervical carotid pseudoaneurysm that was successfully treated using a covered stent.

Influence of periodontal afferent inputs for human cerebral blood oxygenation during jaw movements.

Using functional magnetic resonance imaging (fMRI) and near-infrared spectroscopy (NIRS), we examined the role of periodontal afferent inputs on cerebral activation pattern evoked by masticatory muscle activity in twenty-two subjects. Statistical comparisons were used to identify brain regions with significant activation after subtraction of baseline activity from sham teeth-tapping (no periodontal input) and teeth-tapping (periodontal input) activity in an fMRI (N = 14) and NIRS study (N = 8). Both sham teeth-tapping and teeth-tapping significantly activated bilateral sensorimotor cortex and supplementary motor area in the fMRI study. NIRS revealed that oxygenated hemoglobin concentrations increased in sensorimotor cortex; however, there was no significant difference in degree of oxygenated hemoglobin changes between sham teeth-tapping and teeth-tapping. A control study (N = 8) characterized the jaw muscle activity and amplitude of the two motor tasks and demonstrated significantly higher electromyogram (EMG) activity in the jaw closing muscles during teeth contact in the teeth-tapping session. Since the cerebral activation during sham teeth-tapping and teeth-tapping was similar, we suggest that the influence of periodontal afferent inputs and associated jaw muscle activity is relatively minor compared to the rhythmic jaw movements. Although the clinical significance of the present findings remains unknown, they may have implications for the understanding of awake or sleep-related bruxism characterized by subconscious and rhythmic teeth-grinding or teeth-clenching.

Report on the international Primary Neurosurgical Life Support course in the eighth Asian Congress of Neurological Surgeons in Kuala Lumpur, Malaysia.

On November 22, 2010, a simulation-based hands-on education course for medical staff in the neurosurgical fields was held in 8(th) Asian Congress of Neurological Surgeons (ACNS) in Kuala Lumpur, Malaysia. The present education course called Primary Neurosurgical Life Support (PNLS) course had been started by the Japan Society of Neurosurgical Emergency since 2008. This report summarizes the international version of PNLS course in 8(th) ACNS.

[Stent-assisted angioplasty using the proximal protection method for intracranial internal carotid artery stenosis].

Percutaneous transluminal angioplasty (PTA) with stenting (PTA/stenting) for intracranial atherosclerotic stenoses is usually performed without any embolic protection devise (EPD). However, we have encountered ischemic complications when performing PTA/stenting without EPD for symptomatic intracranial internal carotid artery stenosis. We report here a case of symptomatic intracranial artery stenosis, which was treated by stenting under proximal protection without ischemic complications. The 54-year-old male was admitted to our hospital complaining of motor weakness. Diffusion-weighted image (DWI) in MRI revealed multiple high intensity lesions in the left frontal and parietal lobe. An angiogram demonstrated 80% stenosis in the C5 portion of the left internal carotid artery. PTA/stenting was performed using an occlusion catheter under proximal protection. The occlusion catheter with balloon was placed in the left internal carotid artery of the cervical segment. The balloon was inflated to intercept blood flow, and a driver stent was placed following PTA. Postoperative angiography demonstrated that the degree of stenosis had decreased to almost 5% after PTA/stenting. The patient did not present other neurological deficits. MRI-DWI did not reveal any ischemic lesions following the treatment. PTA/stenting under proximal protection using an occlusion catheter is a simple technique, and is considered to be effective for intracranial internal carotid stenosis.

The Modules for ISLS/PNLS Combined Course as International Version: Report of Workshop in 9 International Conference of Cerebrovascular Surgery.

In Japan, there are two simulation based training systems for neurosurgical diseases, that are ISLS (Immediate Stroke Life Support) and PNLS (Primary Neurosurgical Life Support). Workshop on "First ISLS International Version Trial Task Force" came to a successful conclusion on November 12, 2009, in Nagoya, Japan. More than 30 international participants attended this workshop, organized by the Department of Neurosurgery, Fujita Health University. This report summarizes the modules for ISLS/PSLS combined course as international version from the workshop.

Abnormal single-unit activity recorded in the somatosensory thalamus of a quadriplegic patient with central pain.

We have performed single unit analysis of the activity of cells located in the ventral nuclear group of thalamus in a patient with dysesthetic pain below the level of a clinically complete traumatic spinal cord transection at C5. Cells located in the parasagittal plane 14 mm lateral to the midline responded to tactile stimulation in small facial and intraoral receptive fields, which were characteristic of patients without somatosensory abnormality [30]. In this patient the 16 mm lateral parasagittal plane contained cells with receptive fields located on the occiput and neck instead of the upper extremity as would normally be expected. Cells with receptive fields on the neck and occiput had not previously been observed in recordings from single units (n = 531) responding to somatosensory stimulation [30]. Thus, on the basis of their location in a region of thalamus which normally represents parts of the body below the level of the spinal cord transection and their unusual receptive fields adjacent to these same parts of the body, we propose that the cells in the 16 mm lateral plane have lost their normal afferent input. Analysis of the autopower spectra of spike trains indicates that cells in the 16 mm lateral plane exhibited a higher mean firing rate and greater tendency to fire in bursts than cells in the 14 mm lateral plane (P less than 0.005). Finally, electrical stimulation at the recording sites in the 16 mm lateral plane evoked a burning sensation in the occiput, neck and upper extremity. These results suggest that regions of thalamus which have lost their normal somatosensory input contain neurons which exhibit abnormal spontaneous and evoked activity and that electrical stimulation of these regions can produce the sensation of burning dysesthesia.

Thalamic relay nucleus stimulation for relief of intractable pain. Clinical results and beta-endorphin immunoreactivity in the cerebrospinal fluid.

Deep brain stimulation (thalamic relay nucleus, periaqueductal gray and internal capsule) was applied to various cases of intractable pain, and the resulting degree of pain reduction and alteration in beta-endorphin immunoreactivity in the cerebrospinal fluid (CSF) were compared. The following results were obtained. (1) The studies on intractable pain revealed that the levels of beta-endorphin immunoreactivity in the CSF were lower than those in the control group. (2) Thalamic relay nucleus stimulation proved effective not only for deafferentiation pain, but also for somatogenic pain. No relationship was, however, noted between pain reduction and the rate of increase of beta-endorphin immunoreactivity in the CSF. (3) The incidence of stimulation tolerance following prolonged stimulation of the thalamic relay nucleus can be reduced to a minimum by administration of L-DOPA. It is concluded that the increase in beta-endorphin in the CSF is not the direct and major cause of pain reduction during treatment by thalamic relay nucleus stimulation. It may be assumed that neuronal facilitation on the monoaminergic descending pain inhibitory system plays a role in reducing pain.