Clipping Surgery for Unruptured Middle Cerebral Artery Aneurysms.

Clipping surgeries for 139 consecutive unruptured middle cerebral aneurysms were performed between April 1991 and March 2014. Left hemiparesis occurred in one case (0.7 %). Transient symptoms arose in six patients due to perforator injury, arterial branch occlusion, damage to the venous system, or chronic subdural hematoma. Neither mortality nor decline in cognitive function was noted in this study. Clipping surgery for unruptured middle cerebral artery aneurysms can be done with minimal morbidity. However, meticulous management during the perioperative period as well as the use of modern technologies during the surgery, such as MEP monitoring and ICG videoangiography, are needed for safe and secure clipping surgery.

High-dose methotrexate monotherapy followed by radiation for CD30-positive, anaplastic lymphoma kinase-1-positive anaplastic large-cell lymphoma in the brain of a child.

The authors report the case of an 11-year-old immunocompetent boy with primary CNS CD30-positive anaplastic large-cell lymphoma (ALCL) that was also positive for anaplastic lymphoma kinase-1. His initial clinical manifestation was acute meningitis of unknown etiology. Findings on CT scanning were normal. Although he received empirical treatment against infection, his systemic and neurological status deteriorated. Subsequent MRI revealed newly emerged enhanced lesions and concomitant edema in the left parietal lobe. Diagnosis was confirmed following a brain biopsy and immunohistochemical staining. Three courses of systemic high-dose methotrexate (HD-MTX) treatment with 2-week intervals was started, followed by whole-brain radiation. His clinical course improved, and he has remained disease-free for more than 8 years without any additional treatment. Because ALCL originating in the brain is extremely rare and difficult to diagnose, no standard treatment has been established. This report suggests that systemic HD-MTX monotherapy can be an effective and worthwhile tailored therapeutic option for pediatric primary CNS ALCL.

[Characteristics and treatment of dural and perimedullary arteriovenous fistula at the craniocervical junction presenting with subarachnoid hemorrhage].

Dural and perimedullary arteriovenous fistula (AVF) at the craniocervical junction tend to cause subarachnoid hemorrhage (SAH). However, their natural history and clinical manifestations still remain to be elucidated. From 2003 to 2009, we encountered 5 cases of dural and perimedullary AVF presented with SAH. They were all male, ranging in age from 53 to 85 year-old (mean: 68 year-old). Rebleeding occurred in 1 patient on day 11. Outcome estimated by modified Rankin Scale did not change remarkably from 2.6 on admission to 2.4 at 3 months later on average. Cerebral angiography and 3D-CT angiography disclosed feeders originating from radicular or intracranial vertebral arteries which drained into the epidural venous plexus or spinal meningeal veins. One patient died of systemic complication during his clinical course. Thus we performed open surgery in the remaining 4 patients. Of these, we failed to occlude feeders completely in the initial surgery without intraoperative digital subtraction angiography (DSA) in 2 patients. Following this treatment we performed coil embolization and repeated open surgery with the aid of intraoperative DSA, respectively. In 1 patient out of the remaining 2 patients, we utilized intraoperative DSA to confirm complete disappearance of AVF composed of multiple feeders. These observations show that SAH caused by dural and perimedullary AVF at the craniocervical junction should be mainly treated by open surgery with the aid of intraoperative DSA in order to accomplish obliteration of the feeders because, otherwise, we might fail to confirm complete disappearance of AVF.

Significance of IDH mutations varies with tumor histology, grade, and genetics in Japanese glioma patients.

Mutations in isocitrate dehydrogenase 1 (IDH1) and IDH2 are found frequently in malignant gliomas and are likely involved in early gliomagenesis. To understand the prevalence of these mutations and their relationship to other genetic alterations and impact on prognosis for Japanese glioma patients, we analyzed 250 glioma cases. Mutations of IDH1 and IDH2 were found in 73 (29%) and 2 (1%) cases, respectively. All detected mutations were heterozygous, and most mutations were an Arg132His (G395A) substitution. IDH mutations were frequent in oligodendroglial tumors (37/52, 71%) and diffuse astrocytomas (17/29, 59%), and were less frequent in anaplastic astrocytomas (8/29, 28%) and glioblastomas (13/125, 10%). The pilocytic astrocytomas and gangliogliomas did not have either mutation. Notably, 28 of 30 oligodendroglial tumors harboring the 1p/19q co-deletion also had an IDH mutation, and these alterations were significantly correlated (P < 0.001). The association between TP53 and IDH mutation was significant in diffuse astrocytomas (P = 0.0018). MGMT promoter methylation was significantly associated with IDH mutation in grade 2 (P < 0.001) and grade 3 (P = 0.02) gliomas. IDH mutation and 1p/19q co-deletion were independent favorable prognostic factors for patients with grade 3 gliomas. For patients with grade 3 gliomas and without 1p/19q co-deletion, IDH mutation was strongly associated with increased progression-free survival (P < 0.0001) and overall survival (P < 0.0001), but no such marked correlation was observed with grade 2 gliomas or glioblastomas. Therefore, IDH mutation would be most useful when assessing prognosis of patients with grade 3 glioma with intact 1p/19q; anaplastic astrocytomas account for most of these grade 3 gliomas.

Importance of the initial grade of subarachnoid hemorrhage in the patients with the age of 80 years and older from a single center analysis.

In the developed countries, especially Japan, elderly population is rapidly increasing, but outcomes of elderly patients with the age of 80 years and older suffering from subarachnoid hemorrhage (SAH) remain still unclear. We retrospectively reviewed the medical records of nontraumatic SAH patients aged 80 years and older, who were hospitalized in a single center between 1998 and 2009. There were 28 patients (80-90 years old and 75% female), representing 5.9% of all non-traumatic SAHs (n = 474). Of those, 16 patients received an intervention (ten clipping and six endovascular coiling) and the remaining 12 patients were managed conservatively. The median survival time of intervention group was 110 days and that of conservative group 49 days (p = 0.12, log rank analysis). Cox's proportional hazards model yielded two variables, the Japan Coma Scale (JCS) grade on admission ( hazard ratio: 2.93 [p = 0.009]) and conservative treatment (hazard ratio: 2.14 [p = 0.054]). In the outcome of the modified Rankin Scale between these two groups, logistic regression analysis had significant variable; the JCS grade on admission (odds ratio: 280, [p = 0.020]). In the elderly patients with good initial clinical condition, an acute intervention may have good outcome.

Surgical procedure and results of cisternal washing therapy for the prevention of cerebral vasospasm following SAH.

In 1994, we started cisternal washing therapy (CWT) using urokinase combined with head-shaking method in order to prevent cerebral vasospasm. In this paper, we showed the surgical procedure for CWT and reported the effect of this therapy in preventing vasospasm following SAH. A total of 332 consecutive cases with Fisher group 3 SAH since 1988 were analyzed. Of these patients, 118 cases (56 cases before 1994 and 62 cases after 1994) had not CWT, and, 214 cases after 1994 had this therapy. All of these patients had clipping surgery within 3 days following SAH, and had postoperative management both with normovolemia and normal to mild hypertension. In these two groups, the incidence of symptomatic vasospasm (transiently symptomatic vasospasm without infarction), cerebral infarction due to vasospasm on CT, and mortality and morbidity (M&M) due to vasospasm were analyzed. In the group without CWT, the incidences of symptomatic vasospasm, cerebral infarction on CT, and M&M due to vasospasm were 4.2%, 28.8%, and 17.8%, respectively. On the other hand, in the group with CWT, they were 3.7%, 6.5%, and 2.8%, respectively. In the patients with CWT, the incidence of cerebral infarction on CT due to vasospasm and M&M due to vasospasm were significantly (p < 0.05) decreased. CWT was effective in preventing cerebral vasospasm.

[Acute onset of visual disturbance in a patient with arachnoid cyst in the middle cranial fossa].

Intracranial arachnoid cyst occurs most frequently in the middle fossa. Most of them are asymptomatic with or without neurological involvement. However some develop neurological deficits such as increased intracranial pressure, which manifests as headache, epilepsy and focal neurological deficits. Here we present an adult case of arachnoid cyst in the middle cranial fossa: the patient demonstrated rapidly deteriorating visual field defect and decreased visual acuity. The symptoms were improved by an emergency surgery. This is the first case report describing optic nerve compression due to an arachnoid cyst. Result of the coronal and sagittal magnetic resonance imaging (MRI) scans showed effective optic nerve compression. Long-standing asymptomatic arachnoid cysts might progress rapidly to cause cranial nerve deficits thus meticulous MRI follow-up are important in these patients.

Preservation of the lesser occipital nerve during microvascular decompression for hemifacial spasm. Technical note.

The authors report on their technique for preserving the lesser occipital nerve (LON) during lateral suboccipital craniotomy. In their technique, the LON, which runs along the surface of or just beneath the sternocleidomastoid muscle, is identified and preserved. Lesser occipital nerve preservation using their technique was attempted in 25 patients who underwent microvascular decompression for hemifacial spasm. The LON was successfully preserved in 16 of these patients, was impossible to preserve in two patients, and could not be identified in seven patients. Among the patients in whom LON preservation was successful, 87.5% were free of sensory disturbance 6 months after surgery, whereas both patients in whom the LON could not be preserved complained of sensory disturbances in the occipital area and the posterior part of the auricula. Fifty-seven percent of the patients whose LON could not be identified complained of sensory disturbance. Thus, this technique for preserving the LON reduces the incidence of sensory disturbance in the occipital region after suboccipital craniotomy for microvascular decompression for hemifacial spasm.

Lymphoplasmacyte-rich meningioma with atypical invasive nature.

A 12-year-old boy presented with a lymphoplasmacyte-rich (LPR) meningioma in the posterior fossa. The tumor was subtotally removed. Histological examination showed the tumor had invaded the normal brain tissue despite its benign grade in the World Health Organization classification. The Ki-67 staining index using MIB-1 monoclonal antibody was relatively high. (18)F-2-fluoro-2-deoxy-D-glucose positron emission tomography revealed high uptake in the tumor. These findings indicate the atypical nature of LPR meningioma.

Intracerebroventricular delivery of dominant negative prion protein in a mouse model of iatrogenic Creutzfeldt-Jakob disease after dura graft transplantation.

We have developed a novel procedure in which a small collagen sheet (3 mm x 3 mm) absorbing prion-infected brain homogenates was transplanted onto the brain surface of highly prion-susceptible transgenic mice (Tg(MoPrP)4053/FVB), as an animal model of iatrogenic Creutzfeldt-Jakob disease (iCJD) caused by prion-contaminated cadaveric dura graft transplantation. Using the iCJD model, we further investigated the in vivo efficacy of dominant negative recombinant prion protein with lysine substitution at mouse codon 218 (rPrP-Q218K), which is known to inhibit prion replication in vitro (H. Kishida, Y. Sakasegawa, K. Watanabe, Y. Yamakawa, M. Nishijima, Y. Kuroiwa, N.S. Hachiya, K. Kaneko, Non-glycosylphosphatidylinositol (GPI)-anchored recombinant prion protein with dominant-negative mutation inhibits PrPSc replication in vitro, Amyloid, vol. 11, 2004, pp. 14-20.). Following 7-day intracerebroventricular administration of the rPrP-Q218K via an indwelling catheter connected to the implanted osmotic pump, the median incubation period of Tg(MoPrP)4053/FVB was prolonged considerably from 117 days to 131 days (p=0.016, log-rank test) in the rPrP-Q218K-treated group, even after a lengthy latency period of as long as 30 days by starting the rPrP-Q218K injection. Whether wild-type rPrP, other mutant rPrPs, or the combination of rPrP-Q218K with other anti-prion compounds might extend the survival period in that condition must be further investigated.

Differences in infarct evolution between lipopolysaccharide-induced tolerant and nontolerant conditions to focal cerebral ischemia.

OBJECT: Although brain tissue may be protected by previous preconditioning, the temporal evolution of infarcts in such preconditioned brain tissue during focal cerebral ischemia is largely unknown. Therefore, in this study the authors engaged in long-term observation with magnetic resonance (MR) imaging to clarify the difference in lesion evolution between tolerant and nontolerant conditions. METHODS: Bacterial lipopolysaccharide (LPS; 0.9 mg/kg) was administered intravenously to induce cross-ischemic tolerance. Focal cerebral ischemia was induced 72 hours later in spontaneously hypertensive rats. Serial brain MR images were obtained 6 hours, 24 hours, 4 days, 7 days, and 14 days after ischemia by using a 7.05-tesla unit. Lesion-reducing effects were evident 6 hours after ischemia in the LPS group. Preconditioning with LPS does not merely delay but prevents ischemic cell death by reducing lesion size. Lesion reduction was a sustained effect noted up to 14 days after ischemia. Reduction of local cerebral blood flow (ICBF) in the periinfarct area was significantly inhibited in the LPS group, which was correlated with endothelial nitric oxide synthase (eNOS) expression. CONCLUSIONS: Significant preservation of ICBF in the periinfarct area, which is relevant to sustained upregulation of eNOS, could be a candidate for the long-term inhibiting effect on infarct evolution in the LPS-induced tolerant state.

Proximal occlusion of the middle cerebral artery in C57Black6 mice: relationship of patency of the posterior communicating artery, infarct evolution, and animal survival.

OBJECT: The intraluminal suture model for focal cerebral ischemia is increasingly used, but not without problems. It causes hypothalamic injury, subarachnoid hemorrhage, and inadvertent premature reperfusion. The patency of the posterior communicating artery (PCoA) potentially affects the size of the infarct. In addition, survival at 1 week is unstable. The authors operated on C57Black6 mice to produce proximal middle cerebral artery occlusion (MCAO) so that drawbacks with the suture model could be circumvented. METHODS: The MCA segment just proximal to the olfactory branch was occluded either permanently or temporarily. After 1 hour of MCAO the infarct volume was significantly smaller than that found after 2 hours or in instances of permanent MCAO. The differences were assessed at 24 hours and 7 days after surgery (p < 0.05 and p < 0.001, respectively). The patency of the PCoA, as visualized using carbon black solution, did not correlate with the infarct size. Neurologically, the 1- and 2-hour MCAO groups displayed significantly less severe deficits than the permanent MCAO group on Days 1, 4, and 7 (p < 0.005 and p < 0.01, respectively). Although the infarct size, neurological deficits, and body weight loss were more severe in the permanent MCAO group, the survival rate at Day 7 was 80%. CONCLUSIONS: This model provides not only a robust infarct size (which is not affected by the patency of the PCoA), but also a better survival rate.

Focal hyperperfusion after superficial temporal artery-middle cerebral artery anastomosis in a patient with moyamoya disease. Case report.

Superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis is a standard surgical therapeutic option in patients with moyamoya disease. Most patients experience improvement in their clinical symptoms immediately after surgery. The authors report on the case of a 39-year-old man with moyamoya disease who suffered from temporary and frequent neurological deterioration after undergoing a left STA-MCA anastomosis. Hemodilution and hypervolemia therapies did not improve his course. Technetium-99m hexamethylpropyleneamine oxime single-photon emission tomography scans demonstrated focal intense accumulation of the tracer in the frontal operculum on the side of the surgery. Although diffusion-weighted magnetic resonance (MR) imaging demonstrated no abnormalities except for the postoperative change, perfusion-weighted MR images and MR digital subtraction angiography revealed focal hyperperfusion in the left frontal operculum where the cerebral perfusion reserve was severely disturbed preoperatively. This evidence strongly supports the notion that focal hyperperfusion observed after STA-MCA anastomosis could occur in the poor perfusion reserve area preoperatively and could cause temporary neurological deterioration.

A model of global cerebral ischemia in C57 BL/6 mice.

A reproducible model of global cerebral ischemia in mice is essential for elucidating the molecular mechanism of ischemic neuronal injury. Such a model is particularly important in the mouse because many genetically engineered mutant animals are available. In C57BL/6 and SV129/EMS mice, we evaluated a three-vessel occlusion model. Occlusion of the basilar artery with a miniature clip was followed by bilateral carotid occlusion. The mean cortical cerebral blood flow was reduced to less than 10% of the preischemic value, and the mean anoxic depolarization was attained within 1 minute. In C57BL/6 mice, there was CA1 hippocampal neuronal degeneration 4 days after ischemia. Neuronal damage depended upon ischemic duration: the surviving neuronal count was 78.5 +/- 8.5% after 8-minute ischemia and 8.4 +/- 12.7% after 14-minute ischemia. In SV129/EMS mice, similar neuronal degeneration was not observed after 14-minute ischemia. The global ischemia model in C57BL/6 mice showed high reproducibility and consistent neuronal injury in the CA1 sector, indicating that comparison of ischemic outcome between wild-type and mutant mice could provide meaningful data using the C57BL/6 genetic background. Strain differences in this study highlight the need for consideration of genetic background when evaluating ischemia experiments in mice.

Genome-wide gene expression analysis for induced ischemic tolerance and delayed neuronal death following transient global ischemia in rats.

Genome-wide gene expression analysis of the hippocampal CA1 region was conducted in a rat global ischemia model for delayed neuronal death and induced ischemic tolerance using an oligonucleotide-based DNA microarray containing 8,799 probes. The results showed that expression levels of 246 transcripts were increased and 213 were decreased following ischemia, corresponding to 5.1% of the represented probe sets. These changes were divided into seven expression clusters using hierarchical cluster analysis, each with distinct conditions and time-specific patterns. Ischemic tolerance was associated with transient up-regulation of transcription factors (c-Fos, JunB Egr-1, -2, -4, NGFI-B), Hsp70 and MAP kinase cascade-related genes (MKP-1), which are implicated cell survival. Delayed neuronal death exhibited complex long-lasting changes of expression, such as up-regulation of proapoptotic genes (GADD153, Smad2, Dral, Caspase-2 and -3) and down-regulation of genes implicated in survival signaling (MKK2, and PI4 kinase, DAG/PKC signaling pathways), suggesting an imbalance between death and survival signals. Our study provides a differential gene expression profile between delayed neuronal death and induced ischemic tolerance in a genome-wide analysis, and contributes to further understanding of the complex molecular pathophysiology in cerebral ischemia.

Cardiac arrest cerebral ischemia model in mice failed to cause delayed neuronal death in the hippocampus.

Global cerebral ischemia models for genetically engineered mice are of particular importance for the study of delayed neuronal death, but have been complicated by variability of vascular anatomy. Here we developed a 5-min cardiac arrest model that was not affected by vascular anatomy, and evaluated the hippocampal neuronal injury in BL/6 and SV129 mice. Despite prolonged anoxic depolarization for approximately 7 min, however, no consistent ischemic neuronal injury was noted in the CA1 sector of the hippocampus in both strains. Thus, our observations suggested that murine hippocampal neurons are relatively resistant to ischemia compared with those in other rodents.