安達 一英

Epidermoid cysts constitute less than 1 % of intracranial tumors with the majority of them involving cerebellopontine angle (CPA). Although several mechanisms for cranial nerve dysfunction due to these tumors have been proposed, no direct evaluation for hyper- or hypoactive dysfunction has been done. In this case series, pathophysiology of cranial nerve dysfunction in CPA epidermoid cysts was evaluated with special attention to a new mechanism of capsule strangulation caused by stratified tumor capsule. Twenty-two cases with epidermoid cysts of CPA micro-neurosurgically treated in our departments since 2005 were reviewed. Clinical status of the patients before the surgery and post-operative functional outcome were recorded. Available data from the English literature were summarized for comparison. Mass reduction of cyst contents in most cases was usually associated with prompt and marked improvement of the symptoms suggesting neuroapraxia caused by compression of the tumor content and/or mild ischemia. Among them, two cases showed strangulation of the affected nerves by the tumor capsule whose preoperative dysfunction did not improve after surgery in spite of meticulous microsurgical removal of the lesion. Involved facial and abducent nerves in these two cases showed distortion of nerve axis and nerve atrophy distal to the strangulation site. We report the first direct evidence of etiology of cranial nerve dysfunction caused by cerebellopontine angle epidermoid tumors. Young age and rapidly progressive neurological deficit might be the characteristics for strangulation of the affected nerves by the cyst capsule. Even though the number of cases might be limited, immediate decompression and release of the strangulating band might be urged in such patients to prevent irreversible deficits.

Objective To improve bleeding management during brain tumor surgery, feeder arteries supplying the tumor are often embolized presurgically. However, access to feeder arteries can be limited, and embolization of feeders from internal carotid artery (ICA) branches often causes complications. We evaluated the PercuSurge GuardWire (Medtronic, Minneapolis, Minnesota, United States) system (PGWS) with aspiration catheter as amodification of the embolization technique used to block tumor-supplying branches of the ICA. Methods Two skull-base tumors were treated with preoperative embolization. One was a meningioma; the other was a hemangiopericytoma. In each case, the microcatheter could not be threaded into the ICA feeder arteries. Therefore, particulate embolic material was injected near the ICA branch while maintaining ICA balloon protection by the PGWS at the orifice of the ophthalmic artery. After embolization, we removed the remaining embolic material in the ICA using an aspiration catheter. In both cases, there were no postembolization complications and no high-intensity areas in the diffusion-weighted magnetic resonance image, and the tumorectomy proceeded as scheduled. Conclusion This modified technique may be a promising alternative for reducing embolic complications and improving the success rate, although case accumulation is needed to confirm this result.

When embolizing cerebral aneurysms, dense coil packing may prevent recanalization but this may be influenced by the aneurysm morphology. We have analyzed retrospectively the relationship between anatomic features and the volumetric coil packing density. We analyzed 452 aneurysms in 434 patients treated by coil embolization without stenting, expressing packing density as volume embolization ratio (VER, volume of inserted coils/aneurysm volume). Six morphological variables (neck width, height, maximum diameter, dome to neck ratio (DNR), and aspect ratio), aneurysm location, and whether the aneurysm was ruptured or unruptured were analyzed with respect to dense (VER a parts per thousand yen20 %) or loose (VER < 20 %) packing densities, using logistic regression analysis and ROC analysis. Among 452 aneurysms, VERs > 20 % were achieved for 272 aneurysms, with a mean VER of 24.7 %. The mean VER of the remaining 180 aneurysms was 15.6 %. In univariate analyses, the predictors for dense packing were having an anterior circulation, DNR, aspect ratio, and neck width. In multivariate analysis, the independent predictors were smaller neck width (odds ratio (OR) 0.8735; 95 % confidence interval (CI) 0.7635-0.9993) and larger aspect ratio (OR 1.6679; 95 % CI 1.0460-2.6594). ROC analysis showed optimal cutoff values for an aspect ratio of 1.35 (sensitivity 69.5 %, specificity 51.7 %) and a neck width of 3.13 mm (sensitivity 51.1 %, specificity 27.8 %). Although dense coil packing is still difficult to achieve in wide-necked aneurysms without the use of stents, packing with VER > 20 % is expected to be achieved when the height is 1.35 times larger than the neck width.

Genetic subgrouping of gliomas has been emphasized recently, particularly after the finding of isocitrate dehydrogenase 1 (IDH1) mutations. In a previous study, we investigated whole-chromosome copy number aberrations (CNAs) of gliomas and have described genetic subgrouping based on CNAs and IDH1 mutations. Subsequently, we classified gliomas using simple polymerase chain reaction (PCR)-based methods to improve the availability of genetic subgrouping. We selected IDH1/2 and TP53 as markers and analyzed 237 adult supratentorial gliomas using Sanger sequencing. Using these markers, we classified gliomas into three subgroups that were strongly associated with patient prognoses. These included IDH mutant gliomas without TP53 mutations, IDH mutant gliomas with TP53 mutations, and IDH wild-type gliomas. IDH mutant gliomas without TP53 mutations, which mostly corresponded to gliomas carrying 1p19q co-deletions, showed lower recurrence rates than the other 2 groups. In the other high-recurrence groups, the median progression- free survival (PFS) and overall survival (OS) of patients with IDH mutant gliomas with TP53 mutations were significantly longer than those of patients with IDH wild-type gliomas. Notably, most IDH mutant gliomas with TP53 mutations had at least one of the CNAs +7q, +8q, -9p, and -11p. Moreover, IDH mutant gliomas with at least one of these CNAs had a significantly worse prognosis than did other IDH mutant gliomas. PCR-based mutation analyses of IDH and TP53 were sufficient for simple genetic diagnosis of glioma that were strongly associated with prognosis of patients and enabled us to detect negative CNAs in IDH mutant gliomas.

Background: In embolizing a cerebral aneurysm, achievement of a high-volume embolization ratio (VER: volume of inserted coils / aneurysm volume) is important because it may prevent coil compaction and recanalization. The goal of the study is to examine whether use of softer and longer coils gives an adequate VER with fewer coils, particularly for small aneurysms. Methods: Aneurysm volumes, VERs, and numbers of inserted coils were investigated in 23 cases of small aneurysms embolized using Infini coils, a long soft coil with a primary diameter of 0.010 inches (Infini group). An aneurysm volume-and VER-matched control (non-Infini) group of 59 cases was selected from patients treated at our facility. Data were also compared between subgroups of patients (n = 18 and n = 34 in the Infini and non-Infini groups, respectively) who were not treated with thicker coils with primary diameters of 0.0135-0.015 inches (18-type coils), since these coils affect the number of coils by increasing VER rapidly. Results: Average aneurysm volumes and VERs did not differ significantly between the Infini and non-Infini groups. Significantly fewer coils were used per 0.1 ml aneurysm volume in the Infini group (4.08 coils in average) compared with the non-Infini group (5.67) (p < 0.001). In the non-18-type subgroups, the number of coils used remained significantly smaller in the Infini group (4.49) compared with the non-Infini group (6.72), (p < 0.001). Conclusion: To achieve VER >= 20%, use of Infini coils significantly decreased the number of coils required per unit volume of a small aneurysm.

Neuroepithelial cyst is considered an unusual differential diagnosis for cysts in the posterior fossa. Here, we present a paediatric case with such a pathology and review the pertinent literature. A 12-year old girl with headache, vertigo and disturbed gait was diagnosed with a cystic lesion in the fourth ventricle after brain MRI study. She was operated with the pre-operative diagnosis of arachnoid cyst. A transparent, colourless cyst was observed intra-operatively. As frozen sections were consistent with endodermal cyst, total removal of the cyst was attempted. Definite histopathological studies and immunohistochemistry stains were in favour of neuroepithelial cyst. No regrowth of the cyst or recurrence of the symptoms was observed in her 2-year follow-up. As neuroepithelial cyst is rarely encountered in the posterior fossa, the clinical, radiological and pathological characteristics of our case along with similar cases in the literature were reviewed and discussed.

Exogenous fibrin glue (FG) is highly suitable for neurosurgical procedures, because of its viscosity and adhesive properties. Several FGs are commercially available, but only few reports detail their differences. In the present study, we investigated the viscosity and adhesive performance of two types of FG: one is derived from blood donated in Europe and the United States (CSL Behring's Beriplast (R), BP) and the other is derived from blood donated in Japan (the Chemo-Sero-Therapeutic Research Institute's Bolheal (R), BIT). The viscosity test that measured fibrinogen viscosity revealed that BP had significantly higher viscosity than BH. Similarly, the dripping test showed that BP traveled a significantly shorter drip distance in the vertical direction than BIT, although the transverse diameter of the coagulated FG did not differ statistically significantly. In the tensile strength test, BP showed superior adhesion performance over BH. The histological study of the hematoxylin-eosin-stained specimens in both groups showed favorable adhesion. Although further studies are required on its manufacturing and usage methods, FG shows differences in viscosity and adhesive performance according to the blood from which it is derived. We conclude that it is desirable to select the type and usage method of FG according to the characteristics of the surgical operation in question. Our findings suggest that FG produced from the blood donated in Europe and the United States might be more suitable for use in surgical procedures that demand an especially high degree of viscosity and rapid adhesive performance.

Cavernous malformation with trigeminal neuralgia is relatively rare; only 10 cases have been reported. In deciding treatment strategies, it is helpful to classify cavernous malformation according to its origin, as follows: in the Gasserian ganglion (Type G); between the cisternal and intra-axial portions of the trigeminal nerve root (Type C); in the intra-axial trigeminal nerve root in the pons (Type P); or in the spinal tract of the trigeminal nerve root (Type S). A 62-year-old male presented with left trigeminal neuralgia (V2 area) and left facial hypoesthesia. Imaging studies revealed a cerebellopontine angle mass lesion with characteristics of a cavernous malformation and evidence of hemorrhage. The lesion was completely removed via a left anterior transpetrosal approach. The mass was attached to the trigeminal nerve root; it was located between the cisternal and intra-axial portions of the nerve root, and feeding off microvessels from the trigeminal nerve vascular plexus. Histological examination confirmed a cavernous malformation. In this case, the cavernous malformation was Type C. We review cases of cavernous malformation with trigeminal neuralgia and discuss therapeutic strategies according to the area of origin. (C) 2014 Elsevier B.V. All rights reserved.

脳梗塞とクモ膜下出血を併発した前大脳動脈解離の1例を文献的考察と共に報告する。症例は既往に高血圧がある43歳女性。突然の失語・右片麻痺・意識障害を主訴に当院救急搬送された。来院時の頭部単純CTでクモ膜下出血を認め、造影CTでは左前大脳動脈領域のcerebral blood flow/cerebral blood volume低下と左A2描出不良を認めた。第1病日に施行されたDSAでは左recurrent artery of Heubner分岐直後から末梢にかけてpearl & string signを認め、以上の所見から梗塞・出血同時発症の左前大脳動脈解離と診断した。recurrent artery of Heubner領域の梗塞は生じていなかった。既に左前大脳動脈領域の梗塞巣が完成していた為、血行再建術は併用せずrecurrent artery of Heubnerを温存する形で血管内手術による母血管閉塞を施行した。術後は降圧による保存的治療を施行した。術後2週間のfollow up DSAで塞栓部近位側へ解離が進行している可能性が考えられたものの、recurrent artery of Heubner温存目的で追加塞栓は行わずにそのまま保存的治療を継続した。その後は解離の進行や再出血所見を認めず良好な経過を辿っている。前大脳動脈解離で脳梗塞とクモ膜下出血を併発する症例は稀であり、我々が調査し得た限りでは報告されているのは自験例を含めて16症例のみである。半数以上は保存的治療で良好な経過を辿っているが、同様の発症形式で外科的治療を必要とする再出血ハイリスク症例が存在する可能性がある。報告症例数の少ない現時点では困難だが、効果的な治療選択をする上で今後は症例の蓄積と共に再出血ハイリスク因子の同定が必要だと考えられた。(著者抄録)

Many epidemiological studies on unruptured cerebral aneurysms have reported that the larger the aneurysm, the higher the risk of rupture. However, many ruptured aneurysms are not large. Electrocardiography (ECG)-gated 3D-computed tomography angiography (4D-CTA) was used to detect pulsation in unruptured cerebral aneurysms. The differences in the clinical course of patients in whom pulsation was or was not detected were then evaluated. Forty-two patients with 62 unruptured cystiform cerebral aneurysms who underwent 4D-CTA and follow-up 3D-CTA more than 120 days later were studied. The tube voltage, tube current, and rotation speed were 120 kV, 270 mA, and 0.35 s/rot., respectively. ECG-gated reconstruction was performed, with the cardiac cycle divided into 20 phases. Patients with heart rates higher than 80 bpm were excluded, so 37 patients with 56 aneurysms were analyzed. Pulsation was detected in 20 of the 56 unruptured aneurysms. Of these 20 aneurysms, 6 showed a change in shape at the time of follow-up. Of the 36 aneurysms in which pulsation was not detected, 2 showed a change in shape at follow-up. There was no significant difference in the follow-up interval between the two groups. The aneurysms in which pulsation was detected were significantly more likely to show a change in shape (P = 0.04), with a higher odds ratio of 7.286. Unruptured aneurysms in which pulsation was detected by 4D-CTA were more likely to show a change in shape at follow-up, suggesting that 4D-CTA may be useful for identifying aneurysms with a higher risk of rupture.

The vascular type of Ehlers-Danlos syndrome (vEDS) is an autosomal dominant hereditary disease characterized by connective tissue fragility throughout the body, including the arteries, viscera, and gastrointestinal tract. We report a case in which we performed transvenous embolization (TVE) via direct superior ophthalmic vein (SOV) approach to treat a direct carotid-cavernous fistula (CCF) in a patient with Ehlers-Danlos syndrome (EDS). The patient was a 37-year-old woman who developed tinnitus in her left ear and a headache during examination in the outpatient clinic of another hospital in order to make a definitive diagnosis of vEDS, and she was referred to our hospital and examined. Based on the results of all of the studies she was diagnosed with a CCF. Conservative treatment was attempted, but was not very effective. Because of progressing aphasia, TVE was performed via the SOV direct cut. There were no intraoperative or postoperative complications. It has been reported that cerebral angiography is generally contraindicated in vEDS and that the morbimortality associated with endovascular treatment is very high. When performing treatment it is necessary to be sufficiently aware of the risks it entails.

【目的】妊婦に対する脳血管内治療には,放射線被曝や造影剤,抗血栓療法など,さまざまな問題が存在する.今回,人体ファントム(ランドファントム)を用いて下腹部被曝線量を測定し,胎児に与えうる放射線被曝の影響につき検討したので,自験例2例とともに報告する.【方法】ランドファントムと熱蛍光線量計素子を用いて,頭部血管造影(右上腕穿刺)・脳血管内治療に準じた透視・撮影を行い,生殖腺に相当する部位における被曝線量を計測した.【結果】頭部(外後頭隆起周辺)で最大約800mGy程度の被曝線量に対し,生殖腺相当部位の下腹部における被曝線量は平均0.05mGy程度であり,妊娠中であっても胎児に与える影響は極めて低いことが予想される結果であった.【結論】妊婦に対する脳血管内治療に対して胎児に生じる被曝の影響は極めて低いと考えられた.妊娠中の脳血管内治療には,被曝以外にもさまざまな問題はあるものの,諸注意点に留意すれば安全かつ有効に治療を行うことが可能と考えられる.(著者抄録)

悪性神経膠腫に対して、2013年よりカルムスチン脳内留置用剤を腫瘍摘出腔に留置することが可能となった。脳内留置用剤の有効かつ安全な留置を目的とした、べリプラストPコンビセットエアーレスデバイスを用いた当施設での使用経験に関して報告する。(著者抄録)

OBJECT: Surgery for skull base meningiomas (SBMs) can lead to complications because these lesions are difficult to approach and can involve cranial nerves and arteries. The authors propose a scoring system to evaluate the relative risks and benefits of surgical treatment of SBMs. METHODS: The authors used a 2-step process to construct their scale. First, they derived significant predictive variables from retrospective data on 132 SBM cases treated surgically (primary surgeries only) between May 2000 and December 2005. Next, they validated the predictive accuracy of their scoring system in 60 consecutive cases treated surgically between January 1995 and April 2000, including both primary and repeated surgeries. Finally, they investigated the effect of the surgery on the patients' preoperative symptoms for consecutive cases treated surgically between January 1995 and December 2005, including both primary surgeries and retreatments. RESULTS: Five items that predicted surgical risk were identified: 1) tumor attachment size; 2) arterial involvement; 3) brainstem contact; 4) central cavity location; and 5) cranial nerve group involvement. The authors named their scoring system the ABC Surgical Risk Scale, after the initial letters of these items. Each factor was assigned a score of 0-2 points, and an additional point was added for previous surgical treatment or for radiation, giving a possible total score of 12 points. On average, the scoring system allocated 2 points for gross-total resections, 6.1 points for near-total resections, and 9 points for subtotal resections, with significant differences between groups. For cases scoring >or= 8 points, the percentage of cases showing neurological deterioration postoperatively exceeded the percentage showing improvement. CONCLUSIONS: The authors conclude that this scoring system can be used to predict the extent of tumor removal and that the scores reflect the surgical risk.

Background: To date, 50 cases of cavernous angioma in the CPA have been reported, and previous reports did not describe the tumor's site of origin. We describe a case of a small, extraaxial cavernous angioma of the vestibular nerve. We also propose a reclassification system for cavernous angioma of the CPA based on the tumor's site of origin. Case Description: A 39-year-old female patient had recurrent deteriorating vertigo and a right hearing disturbance. Magnetic resonance imaging revealed a cavernous angioma of the right CPA. Surgery was per-formed through a right lateral suboccipital approach. In the present case, the mass was attached to and covered the cisternal portion of the vestibular nerve, and it contained microvessels that were fed from the vascular plexus of the vestibular nerve. The tumor was resected en bloc, and the microvessels feeding it were cauterized. Conclusions: On the basis of our review of 50 cases of cavernous angioma of the CPA, we propose that these tumors can be classified according to whether they develop from the venous plexus of the dura matter or of a cranial nerve. We also suggest that the site of origin affects the postoperative symptoms. (C) 2008 Elsevier Inc. All rights reserved.

The subventricular zone (SVZ) is the largest germinal zone in the mature rodent brain, and it continuously produces young neurons that migrate to the olfactory bulb. Neural stem cells in this region generate migratory neuroblasts via highly proliferative transit-amplifying cells. The Wnt/beta-catenin signaling pathway partially regulates the proliferation and neuronal differentiation of neural progenitor cells in the embryonic brain. Here, we studied the role of beta-catenin signaling in the adult mouse SVZ. P-Catenin-dependent expression of a destabilized form of green fluorescent protein was detected in progenitor cells in the adult SVZ of Axin2-d2EGFP reporter mice. Retrovirus-mediated expression of a stabilized beta-catenin promoted the proliferation of Mashl+ cells and inhibited their differentiation into neuroblasts. Conversely, the expression of Dkkl, an inhibitor of Wnt signaling, reduced the proliferation of Mashl+ cells. In addition, an inhibitor of GSK3)3 promoted the proliferation of Mashl+ cells and increased the number of new neurons in the olfactory bulb 14 days later. These results suggest that beta-catenin signaling plays a role in the proliferation of progenitor cells in the SVZ of the adult mouse brain.

A 62-year-old Japanese male patient presented with right oculomotor, abducens, and trigeminal nerve disturbances. Neuroimaging revealed a right middle cranial fossa mass lesion with the characteristics of trigeminal schwannoma. The patient underwent a right temporal craniotomy for gross total resection. Histological examination confirmed a metastasis of adenoid cystic carcinoma (ACC). After the operation, no evidence of the primary lesion could be found. The patient was treated with radiation therapy. ACC can be difficult to identify before histological confirmation. The incidence of intracranial invasion of ACC is 4-22%, but in this case no evidence of the primary lesion was found.

Recent studies have revealed that the adult mammalian brain has the capacity to regenerate some neurons after various insults. However, the precise mechanism of insult-induced neurogenesis has not been demonstrated. In the normal brain, GFAP-expressing cells in the subventricular zone (SVZ) of the lateral ventricles include a neurogenic cell population that gives rise to olfactory bulb neurons only. Herein, we report evidence that, after a stroke, these cells are capable of producing new neurons outside the olfactory bulbs. SVZ GFAP-expressing cells labeled by a cell-type-specific viral infection method were found to generate neuroblasts that migrated toward the injured striatum after middle cerebral artery occlusion. These neuroblasts in the striatum formed elongated chain-like cell aggregates similar to those in the normal SVZ, and these chains were observed to be closely associated with thin astrocytic processes and blood vessels. Finally, long-term tracing of the green fluorescent-labeled cells with a Cre-loxP system revealed that the SVZ-derived neuroblasts differentiated into mature neurons in the striatum, in which they expressed neuronal-specific nuclear protein and formed synapses with neighboring striatal cells. These results highlight the role of the SVZ in neuronal regeneration after a stroke and its potential as an important therapeutic target for various neurological disorders.

Interleukin (IL)-6 expression transiently increases in the acute phase of cerebral ischemia. To investigate the physiological significance of endogenous IL-6 expression and to identify the main signal pathway for the action of IL-6, we administered anti-mouse IL-6 receptor monoclonal antibody (IL-6RA), which blocks IL-6 signaling, to mice immediately after a 45-min period of middle cerebral artery occlusion (MCAO). At 6 h after MCAO, IL-6RA administration had resulted in a significant reduction in the amount of phosphorylated signal transducer and activator of transcription-3 (Stat3) protein in the peri-infarct area of the cortex. At 24 h after MCAO, blockade of IL-6 signaling had led to an increase in number of apoptotic cells in the peri-infarct area and enlargement of the size of the infarct, and it had adversely affected neurological function. These results suggest that endogenous IL-6 plays a critical role in preventing damaged neurons from undergoing apoptosis in the acute phase of cerebral ischemia and that its role may be mediated by Stat3 activation.

A 25-year-old male presented with an intracranial tuberculoma mimicking falx meningioma manifesting as right lower monoparesis. The patient had a past history of pulmonary tuberculosis, cured by antituberculous therapy. Computed tomography and magnetic resonance (MR) imaging showed a lesion mimicking a falx meningioma. Surgery achieved subtotal resection. Histological and biochemical examinations revealed the surgical specimen was tuberculoma. He was treated with antituberculous therapy, and his gait disturbance disappeared. Follow-up MR imaging showed no regrowth.