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To investigate relationships between hemodynamic responses and neural activities in the somatosensory cortices, hemodynamic responses by near infrared spectroscopy (NIRS) and electroencephalograms (EEGs) were recorded simultaneously while subjects received electrical stimulation in the right median nerve. The statistical significance of the hemodynamic responses was evaluated by a general linear model (GLM) with the boxcar design matrix convoluted with Gaussian function. The resulting NIRS and EEGs data were stereotaxically superimposed on the reconstructed brain of each subject. The NIRS data indicated that changes in oxy-hemoglobin concentration increased at the contralateral primary somatosensory (SI) area; responses then spread to the more posterior and ipsilateral somatosensory areas. The EEG data indicated that positive somatosensory evoked potentials peaking at 22 ms latency (P22) were recorded from the contralateral SI area. Comparison of these two sets of data indicated that the distance between the dipoles of P22 and NIRS channels with maximum hemodynamic responses was less than 10 mm, and that the two topographical maps of hemodynamic responses and current source density of P22 were significantly correlated. Furthermore, when onset of the boxcar function was delayed 5–15 s (onset delay), hemodynamic responses in the bilateral parietal association cortices posterior to the SI were more strongly correlated to electrical stimulation. This suggests that GLM analysis with onset delay could reveal the temporal ordering of neural activation in the hierarchical somatosensory pathway, consistent with the neurophysiological data. The present results suggest that simultaneous NIRS and EEG recording is useful for correlating hemodynamic responses to neural activity.

Background Accumulating evidence indicates that cancer stem cells (CSCs) drive tumorigenesis. This suggests that CSCs should make ideal therapeutic targets. However, because CSC populations in tumors appear heterogeneous, it remains unclear how CSCs might be effectively targeted. To investigate the mechanisms by which CSC populations maintain heterogeneity during self-renewal, we established a glioma sphere (GS) forming model, to generate a population in which glioma stem cells (GSCs) become enriched. We hypothesized, based on the clonal evolution concept, that with each passage in culture, heterogeneous clonal sublines of GSs are generated that progressively show increased proliferative ability. Methodology/Principal Findings To test this hypothesis, we determined whether, with each passage, glioma neurosphere culture generated from four different glioma cell lines become progressively proliferative (i.e., enriched in large spheres). Rather than monitoring self-renewal, we measured heterogeneity based on neurosphere clone sizes (#cells/clone). Log-log plots of distributions of clone sizes yielded a good fit (r>0.90) to a straight line (log(% total clones) = k*log(#cells/clone)) indicating that the system follows a power-law (y = xk) with a specific degree exponent (k = −1.42). Repeated passaging of the total GS population showed that the same power-law was maintained over six passages (CV = −1.01 to −1.17). Surprisingly, passage of either isolated small or large subclones generated fully heterogeneous populations that retained the original power-law-dependent heterogeneity. The anti-GSC agent Temozolomide, which is well known as a standard therapy for glioblastoma multiforme (GBM), suppressed the self-renewal of clones, but it never disrupted the power-law behavior of a GS population. Conclusions/Significance Although the data above did not support the stated hypothesis, they did strongly suggest a novel mechanism that underlies CSC heterogeneity. They indicate that power-law growth governs the self-renewal of heterogeneous glioma stem cell populations. That the data always fit a power-law suggests that: (i) clone sizes follow continuous, non-random, and scale-free hierarchy; (ii) precise biologic rules that reflect self-organizing emergent behaviors govern the generation of neurospheres. That the power-law behavior and the original GS heterogeneity are maintained over multiple passages indicates that these rules are invariant. These self-organizing mechanisms very likely underlie tumor heterogeneity during tumor growth. Discovery of this power-law behavior provides a mechanism that could be targeted in the development of new, more effective, anti-cancer agents.

The clinical features and endoscopic findings were investigated in 20 patients with isolated lateral ventricle treated by neuroendoscopic septostomy to establish cerebrospinal fluid communication and open an isolated ventricular compartment. The endoscopic procedure was incomplete because of thickened septum pellucidum and insufficient working space in two adults with postmeningitic hydrocephalus. Two children underwent second septostomy. In all other cases, results were good and there were no complications related to endoscopic procedures. Endoscopic septostomy is less invasive and has few complications. Intraoperative navigation and the biportal approach may be required in difficult cases with multiple septum formation and severe postmeningitic hydrocephalus. Adequate stomal size is required in high-risk groups including children under 2 years of age.

A 60-year-old male presented with subarachnoid hemorrhage (SAH) of unknown origin and died of peritonitis 2 months after the ictus. Computed tomography on admission revealed localized hemorrhage at the interpedunclar cistern and sedimentation in both posterior horns. Repeat angiography could not detect any aneurysm. Postmortem histological examination revealed disruption of the wall associated with intramural hemorrhage at the top of the basilar artery, and subintimal hemorrhages of the lower basilar artery and the left vertebral artery. Arterial dissection of the vertebrobasilar system may be a cause of SAH of unknown origin including perimesencephalic hemorrhage.

We attempted to determine whether the plasma concentration of basic fibroblast growth factor (bFGF) was elevated in brain tumor patients. The plasma concentration of bFGF was measured in 55brain tumor patients and 17 normal subjects by enzyme immunoassay. Upper limit of plasma bFGF in the normal subjects was 1.6 pg/ml. Elevated plasma bFGF levels were observed in 28 patients including 13 of 17 glioma patients, eight of 19 benign tumor patients, and seven of 19 malignant tumor patients. Twelve of 14 malignant glioma patients had elevated plasma bFGF levels. There was a good correlation (r = 0.42, p < 0.05) between the elevated plasma bFGF level and the tumor volume. Further studies are needed to determine whether the plasma bFGF level is a clinically useful diagnostic and prognostic marker for patients with brain tumors. 脳腫瘍患者の血漿中にbasic fibroblast growth factor (bFGF)が上昇しているかどうか検討した。対象は55例の脳腫瘍患者で、17名の健康成人をコントロールとした。健康成人の血漿bFGF値の上限は1.6pg/mlであり、脳腫瘍患者でこの値を超えたのは28例(51%)であった。これらの内訳は、グリオーマ患者17例中13例、良性腫瘍19例中8例、悪性腫瘍19例中7例で、特に悪性グリオーマでは14例中12例と高頻度であった。これら脳腫瘍患者では血数bFGF値とMRIから計測した腫瘍体積とはよく相関した。以上、血槃bFGF値は脳腫瘍患者の過半数で上昇していたが、腫瘍マーカーとしての有用性を示すためにはさらに検討が必要と考えられた。

A 10-year-old boy with progressive left visual disturbance associated with craniobasal fibrous dysplasia underwent left frontotemporal craniotomy. Dysplastic lesions of the sphenoid ridge, orbital roof, anterior clinoid, and ethmoid sinus were removed through an extradural pterional approach and the optic nerve was completely decompressed. His vision was markedly improved postoperatively. Consecutive follow-up studies for 3 years have shown no deterioration of his visual acuity. Early optic nerve decompression is highly recommended to preserve visual function in patients with craniofacial fibrous dysplasia causing visual disturbance. 症例は10歳、男児。進行する左眼視力低下を主訴に入院した。神経放射線学的所見から頭蓋底部fibrous dysplasiaと診断し、左前頭側頭開頭を行った。硬膜外アプローチにて蝶形骨翼、眼窩上壁、前床突起、篩骨洞内に増殖した病的骨組織を切除し、左視神経管を解放し視神経を徐圧した。術後、左眼視力は劇的に改善しその後3年間にわたる経過観察期間中に視力の再増悪は認めていない。視力低下を主訴とする顔面頭蓋骨のfibrous dysplasiaの症例に対しては、早期の積極的な外科治療が行われるべきである。

The levels of platelet-activating factor (PAF) and lipid metabolites related to choline glycerophospholipid were measured in the plasma and hematoma samples obtained from patients with chronic subdural hematoma. The ratio of lyso-choline glycerophospholipids (lysoPC) to choline glycerophospholipids (PC) in hematoma correlated with the interval between the onset of symptoms and surgery. PC and lysoPC fatty acyl moieties in plasma and hematoma were essentially similar. These results suggest that the lysoPC to PC ratio in hematoma can determine the age of the chronic subdural hematoma, and that the origin of hematoma may be circulating blood. The levels of PAF in the plasma of chronic subdural hematoma patients were significantly greater than in healthy volunteers. PAF may be involved in the enlargement of chronic subdural hematoma.

Cusimanoらは、pseudo-cerebrospinal fluid(CSF) rhinorrheaという病態を初めて報告したが、我々も同様の一例を経験したので報告した。症例は41歳女性。右三叉神経第1枝領域の知覚鈍麻を主訴とし、petrous先端部に腫瘍性瘤変(tentorial meningioma)を認めた。transpetrosal approachによるpetrosectomyの際、greater superficial petrosal nerve (GSPN)は切断したが、術後2週間後より患側のrhinorrheaを認める様になった。Pseudo-CSF rhinorrheaは, GSPNの切断により自律神経系がアンバランスとなり何らかのhypersensitivityが生じ粘液分泌亢進が起こると考えられた。頭蓋底手術に際し、注意すべき一瘤態と思われた。 A 41-year-old female underwent complete resection of a left petroclival meningioma via an anterior transpetrosal approach, during which the greater superficial petrosal nerve was divided. On the 14th day after the operation, she first noticed leakage of clear fluid from her right nostril whenever the ambient room temperature rose.This pseudo-cerebrospinal fluid rhinorrhea may have developed because of parasympathetic hypersensitivity due to division of the greater superficial petrosal nerve.

Intradiploic arachnoid cystはX線単純写真上境界明瞭な骨融解像として描出され、傍矢状部に多発性に発生し、高齢者に多いことが特徴である.しかし、これまでに報告例は少なく、真の病態はなお不明であり、多くの例では外科的手術なしではその診断が困難である.我々は、63才男性で、前側頭部に非外傷性で単発性のIntradiploic arachnoid cystを認めた稀な一症例を経験したので報告する. A 63-year-old male presented with an unusual case of nontraumatic intradiploic arachnoid cyst in the frontotemporal convexity area.Skull radiography showed a circular osteolytic lesion of the right parietal bone.Computed tomography revealed a defect of the inner table, widened diploic space, and thinned outer table.Magnetic resonance imaging showed a cyst containing cerebrospinal fluid.Bone scintigraphy showed no abnormal uptakes.Intraoperative observation confirmed the neuroimaging findings.Histological examination found no abnormal findings in specimens of skull bone or arachnoid membrane.Intradiploic arachnoid cyst is characterized by parasagittal, multiple, welldemarcated osteolytic lesions on radiographs in the elderly.However, the clinical features of this disease remain unclear and diagnosis without an exploratory surgical procedure may not be possible.

Brain temperature was measured at various depths beneath the pial surface in patients with hydrocephalus of varying aetiology. Temperature increased gradually with depth in all patients, with the highest temperature found in the ventricle. The difference between intraventricular and rectal temperatures (delta v-r) was greater in patients who underwent continuous ventricular drainage than in patients who underwent ventriculoperitoneal shunt (continuous ventricular drainage; 1.2 (SD 0.40) degrees C, mean (SD), n=5 v ventriculoperitoneal shunt; 0.4 (SD 0.45) degrees C, n=16; p< 0.05). The difference between intracerebral and rectal temperatures (delta b2-r) was also greater in patients with continuous ventricular drainage than in patients with ventriculoperitoneal shunt (continuous ventricular drainage; 0.1 (SD 0.86) degrees C, n=5 v ventriculoperitoneal shunt; -0.7 (0.86) degrees C, n=16; p< 0.05). Among patients with normal pressure hydrocephalus, these differences were greater in the patients with better outcomes after shunt surgery than in the less improved group (delta v-r; 0.7 (SD 0.27) degrees C, n=7 v 0.1 (SD 0.40) degrees C, n=5, p< 0.01, delta b2-r; -0.2 (SD 0.61) degrees C, n=7 v -1.4 (0.90) degrees C, n=5, p< 0.01).

A 69-year-old female with frequent episodes of vertigo was found to have persistent trigeminal artery and ulcerative stenosis of the ipsilateral carotid bifurcation. The clinical symptoms, pathogenesis, and treatment of this anomaly are discussed.

A 72-year-old male hospitalized for disturbance of consciousness and vomiting was found to have a left vertebral artery fenestration and a left posterior inferior cerebellar artery aneurysm. The aneurysm was successfully clipped through the lateral suboccipital approach and he recovered with minimal deficits. The association of vertebral artery fenestration and posterior inferior cerebellar artery aneurysm is rare, and their etiologies and relationship are discussed.