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Objectives: To evaluate whether cortical spreading depolarizations (CSD) occur in the early stage after cortical intracerebral hemorrhage (ICH).

Objective: We correlated oxygen, flow, and pressure indices of cerebrovascular reactivity (CR) with extracellular cerebral metabolite concentrations in a porcine model of intracerebral hemorrhage (ICH).

Nonviral, site-specific gene delivery to deep tissue is required for gene therapy of a spinal cord injury. However, an efficient method satisfying these requirements has not been established. This study demonstrates efficient and targeted gene transfer into the spinal cord by using photomechanical waves (PMWs), which were generated by irradiating a black laser absorbing rubber with 532-nm nanosecond Nd:YAG laser pulses. After a solution of plasmid DNA coding for enhanced green fluorescent protein (EGFP) or luciferase was intraparenchymally injected into the spinal cord, PMWs were applied to the target site. In the PMW application group, we observed significant EGFP gene expression in the white matter and remarkably high luciferase activity only in the spinal cord segment exposed to the PMWs. We also assessed hind limb movements 24 h after the application of PMWs based on the Basso-Beattie-Bresnahan (BBB) score to evaluate the noninvasiveness of this method. Locomotor evaluation showed no significant decrease in BBB score under optimum laser irradiation conditions. These findings demonstrated that exogenous genes can be efficiently and site-selectively delivered into the spinal cord by applying PMWs without significant locomotive damage.

Light scattering signal, which is sensitive to cellular/subcellular structural integrity, is a potential indicator of tissue viability in brain, because metabolic energy is used in part to maintain the structure of the cells. We performed near-infrared scattering imaging of rat brain during hypoxia followed by reoxygenation to examine spatiotemporal scattering change due to anoxic depolarization and its correlation with tissue reversibility. For imaging change in light scattering of rat brain, NIR light was transmitted from a halogen lamp with a bandpass filter (800 ± 70 nm) and it was incident onto the entire cortex through the intact skull at an oblique angle; diffusely reflected light from the brain was imaged with a charge-coupled device. About 2 min after starting hypoxia, scattering waves were generated focally in the bilateral outermost regions in the cortex and spread toward the midline at a rate of ~6 mm/min. When reoxygenation was started before the leading edges of scattering waves reached the midline of the brain, the scattering waves disappeared gradually and the tissue was saved. Reoxygenation when scattering wave reached the midline did not save the brain. These results suggest that the coverage of the scattering waves determine the brain tissue reversibility after hypoxia.

Chronic subdural hematoma is one of the most common disorders observed in routine neurosurgical care. In the vast majority of cases, this disorder is treated by surgical evacuation, which usually yields a good prognosis. However, the recurrence rates after this initial procedure range from approximately 5% to 30%. In this study, we focused on the recurrence rate of chronic subdural hematoma and its prevention. We reviewed the risk factors for recurrence, surgical procedures used, perioperative management, timing of operation, and medical treatment.

Objectives: To describe an endoscopic technique to evacuate acute intracerebral hemorrhage (ICH) using the balanced suction-irrigation method in patients with intrinsic or iatrogenic coagulopathies. Methods: We report on our early experience with four patients with atypical ICH related to intrinsic and iatrogenic coagulopathies. In all patients, an endoscopic hematoma evacuation was performed using a navigated burrhole approach. The entry site and trajectory were planned according to the long axis of the hematoma. Results: Every operation was carried out with the aid of neuronavigation. Gross total removal of the hematoma was not intended as first line, especially if eloquent areas could be avoided. Intra-hematomal evacuation leaving minimal hematoma remnants was performed in three of four patients. We report hematoma removal rates of approximately 90%. In all patients, a significant hematoma reduction was achieved, although residues were tolerated to limit neurological damage. No re-hemorrhage was observed. Conclusion: The endoscopic technique with the aid of neuronavigation may be an appropriate method to safely evacuate ICH in the acute stage in patients with intrinsic or iatrogenic coagulopathies.

Objectives: To describe early perihemorrhagic changes after lobar intracerebral hemorrhage (ICH) using multiparametric neuromonitoring [intracranial pressure (ICP), cerebral blood flow (CBF), tissue oxygenation (PbrO2), microdialysis (MD)].

Decompressive craniectomy is one therapeutic option for severe traumatic brain injury (TBI), and it has long been used for the treatment of patients with malignant post-traumatic brain edema. A lack of definitive evidence, however, prevents physicians from drawing any conclusions about the effects of decompressive craniectomy for the treatment of TBI. Therefore, the aim of the present study was to investigate the influence of decompressive craniectomy on post-traumatic brain edema formation. The aquaporin-4 (AQP4) water channel is predominantly expressed in astrocytes, and it plays an important role in the regulation of brain water homeostasis. In the present study, we investigated the time course of AQP4 expression and the water content of traumatized cortex following decompressive craniectomy after TBI. Adult male Sprague-Dawley rats (300-400 g) were subjected to lateral fluid percussion injury using the Dragonfly device. The effect of decompressive craniectomy was studied in traumatized rats without craniectomy (closed skull, DC-), and in rats craniectomized immediately after trauma (DC+). AQP4 expression was investigated with a Western blot analysis and immunohistochemistry. Brain edema was measured using the wet weight/dry weight method. At 48 h after TBI, AQP4 expression of the DC- group was significantly increased compared with the DC+ group (p 0.01). In addition, the cortical water content of the DC- group was significantly increased compared to the DC+ group at the same time point (p 0.05). The present results suggest that decompressive craniectomy may affect AQP4 expression and reduce brain edema formation after TBI.

Light scattering signal is a potential indicator of tissue viability in brain because cellular and subcellular structural integrity should be associated with cell viability in brain tissue. We previously performed multiwavelength diffuse reflectance measurement for a rat global ischemic brain model and observed a unique triphasic change in light scattering at a certain time after oxygen and glucose deprivation. This triphasic scattering change (TSC) was shown to precede cerebral ATP exhaustion, suggesting that loss of brain tissue viability can be predicted by detecting scattering signal. In the present study, we examined correlation between light scattering signal and tissue reversibility in rat brain in vivo . We performed transcranial diffuse reflectance measurement for rat brain; under spontaneous respiration, hypoxia was induced for the rat by nitrogen gas inhalation and reoxygenation was started at various time points. We observed a TSC, which started at 140 ± 15 s after starting nitrogen gas inhalation (mean ± SD, n=8). When reoxygenation was started before the TSC, all rats survived (n=7), while no rats survived when reoxygenation was started after the TSC (n=8). When reoxygenation was started during the TSC, rats survived probabilistically (n=31). Disability of motor function was not observed for the survived rats. These results indicate that TSC can be used as an indicator of loss of tissue reversibility in brains, providing useful information on the critical time zone for treatment to rescue the brain.

We describe three rare cases of dissecting aneurysms in the anterior cerebral artery (ACA) treated by surgical reconstruction, and reviewed 79 previously reported cases with the ACA dissecting aneurysm. We found that 35 (77.8%) of 45 patients with ischemic event and 15 (40.5%) of 37 patients with hemorrhagic event were treated conservatively, with 11.4% (4/35 cases) and 13.3% (2/15) risk of bleeding and rebleeding, respectively. Furthermore, half of these patients died. The other 32 patients were treated surgically, and their outcome was favorable, especially after surgical reconstruction. Simultaneous treatment of both hemorrhagic and ischemic events is essential. We recommend early treatment with revascularization for patients with ACA dissection that has hemorrhaged and for patients presenting with signs of clinical deterioration with ischemic event.

L-type amino acid transporter 1 (LAT1) is proposed to be a major nutrient transporter at the blood brain barrier. LAT1 requires the heavy chain of 4F2 cell surface antigen (4F2hc) for functional expression.We investigated the expression of this heterodimeric transporter after traumatic spinal cord injury in rat by using immunohistochemical and western blot analyses.LAT1 immunoreactivities were up-regulated in the capillary endothelia in close to the injury epicenter 24 hours after injury. It reached a peak at 48 hours after injury, and thereafter decreased. 4F2hc was abundant and unchanged all through the time course after SCI. Western blot analysis under reductive and non-reductive conditions showed that LAT1 and 4F2hc were conjugated as a heterodimeric transporter and the functional regulation was dependent on the light chain, LAT1.We suggest that LAT1 may be transiently upregulated as part of the tissue-repair process after traumatic contusion injury in the spinal cord.

Measurement of intrinsic optical signals (IOSs) is attractive for noninvasive, real-time monitoring of tissue viability in brains. We previously performed measurement of IOSs for a rat global ischemic brain model that was made by rapidly removing blood by saline infusion, and observed that after an induction of ischemia, a unique triphasic change in light scattering occurred. This scattering change preceded the reduction of CuA in cytochrome c oxidase which has been shown to correlate with cerebral ATP decrease. In the present study, we examined whether such triphasic scattering change can be observed in the presence of blood in vivo. Transcranial measurement of diffuse reflectance was performed using a broadband tungsten lamp for a rat brain during hypoxia that was induced by N2 inhalation. The reflectance spectral changes in the visible (500-600 nm) and near-infrared (NIR) (650-850 nm) regions were analyzed to monitor changes in hemodynamics and light scattering, respectively. After starting N2 inhalation, reflectance signals in the visible region showed an increase in deoxy-hemoglobin concentration, and about 80 s after full deoxygenation of hemoglobins, reflectance signals in the NIR region showed a similar triphasic change, which was attributable to change in light scattering. Simultaneous measurement of cerebral EEG showed that neuronal activity ceased about 50 s before this triphasic scattering change. These results show that light scattering will become an important indicator of loss of tissue viability in brain; brain tissue can probably be saved if reoxygenation is achieved before starting this scattering change.

Background L-type amino acid transporter 1 (LAT1) is proposed to be a major nutrient transporter at the blood brain barrier. LAT1 requires the heavy chain of 4F2 cell surface antigen (4F2hc) for functional expression. Methods We investigated the expression of this heterodimeric transporter after traumatic spinal cord injury in rat by using immunohistochemical and western blot analyses. Findings LAT1 immunoreactivities were up-regulated in the capillary endothelia in close to the injury epicenter 24 hours after injury. It reached a peak at 48 hours after injury, and thereafter decreased. 4F2hc was abundant and unchanged all through the time course after SCI. Western blot analysis under reductive and non-reductive conditions showed that LAT1 and 4F2hc were conjugated as a heterodimeric transporter and the functional regulation was dependent on the light chain, LAT1. Conclusions We suggest that LAT1 may be transiently upregulated as part of the tissue-repair process after traumatic contusion injury in the spinal cord.

We report a case in which hemorrhage occurred in an asymptomatic falx meningioma known beforehand, after the internal use of low-dose aspirin for 16 months. Our case is the second one in which hemorrhage from a meningioma may have been induced by aspirin prophylaxis. On the other hand, aspirin may have promoted the enlargement of spontaneous hemorrhage from meningioma. Furthermore, inadequate control of hypertension may have been another cause of hemorrhage. Although it is difficult to solely attribute intratumoral hemorrhage to aspirin, we have to be careful when prescribing aspirin for patients who have asymptomatic meningioma.

We report here a rare case of supratentorial ectopic cortical ependymoma. This tumor was localized in the left angular gyrus, occurred with intratumoral hemorrhage, was attached to the dura mater, exhibited no continuity with the ventricular system, showed distinctive pathological features (perivascular pseudo-rosette formations and firework-like giant rosette formations), and finally transformed to a glioblastoma-like high-grade lesion. A cortical ependymoma should be considered in the differential diagnosis of supratentorial cortical tumors with intraparenchymal hemorrhage and high vascularity, even if not in contact with the ventricular system. Although malignant transformation is unusual in cortical ependymoma, close observation and adjunctive radiotherapy are strongly recommended after the excision.

The arrangement within the midbrain oculomotor nerve complex and crossed innervation of the superior rectus muscle are not elucidated in humans. A 65-year-old woman visited our hospital complaining of difficulty opening her eyes. Neurological examination revealed bilateral ptosis and impaired supraduction. The pupils prompty constricted to light. Results of CT and MRI demonstrated that there was a hematoma located in the dorsal midbrain tegmentum that spared the rostral mid-brain. It was presumed that the nerves of the superior rectus and levator palpebrae lie in the midbrain tegmentum more dorsally and medially than the others. Furthermore, crossed innervation of the superior rectus muscle can explain that lesions located in the dorsal midbrain tegmentum cause more often impaired supraduction.

Anterior wall aneurysms of the internal carotid artery (AWAICA) are relatively uncommon. We investigated the distribution of the subarachnoid clot on computerized tomography (CT) scans in patients with ruptured AWAICA and compared the findings with those in patients with internal carotid artery aneurysms (ICAA) at other sites. Twenty-six ruptured ICAA patients were included in this study. Four (15.4%) of these had an AWAICA and 22 had an ICAA at other sites. Three of the 4 patients with AWAICA had an ordinary 'saccular type' aneurysm and the other had a 'blood blister-like' aneurysm. In all three patients with a 'saccular type' AWAICA, accumulation of the subarachnoid clot in the olfactory sulcus was noted on CT scan. In the patient with a 'blood blister-like' aneurysm and in 22 patients with ICAA at other sites, there were no specific correlations between focal accumulations of the subarachnoid clot and aneurysm location. The accumulation of subarachnoid clot in the olfactory sulcus on CT scan may suggest a ruptured 'saccular type' AWAICA.

Intracranial meningeal melanocytoma is an uncommon tumor that is considered benign. We formerly reported an intracranial meningeal melanocytoma. Here we report a extremely rare case of malignant transformation of this tumor. A 49-year-old man complained of a headache. Magnetic resonance scanning revealed a mass in the left frontal region. The patient underwent gross total removal of the tomor in 1994. The histological findings showed a meningeal melanocytoma. In 1998, he underwent gamma-knife surgery for local recurrence. An additional operation was performed in 1999 became tumor growth was not stopped. The tumor was partially excised by left frontal craniotomy. Histopathological examination revealed a malignant melanoma originating from a melanocytoma. The tumor was composed of a proliferation of severely atypical melanocytoid cells with slightly irregular nuclei and prominent nucleoli, associated with necrosis and hemorrhage. Mitotic figures were encountered occasionally. After six months, he died from cerebrospinal fluid dissemination of this tumor. To our knowledge, this is the first report of malignant transformation of an intracranial meningeal melanocytoma.