Published papers

Background: Unruptured intracranial aneurysms (UIAs) are not uncommon, especially in Japan. Treatment strategy for UIAs has evolved in the past decades in Western countries with the increased use of endovascular treatment as the primary option, but in Japan, clipping still has the upper hand. Methods: This study retrospectively included 200 patients treated by clipping or coiling for UIAs located in the anterior cerebral circulation. Postoperative angiographic and clinical outcomes were evaluated. Results: Of 200 UIAs, 147 and 53 were treated by surgery and coiling, respectively. The average follow-up duration was 30.2 ± 18.8 months for clipping and 29.3 ± 17.6 months for coiling. Complete occlusion was greater in the surgery group (78.9%) than the endovascular group (18.8%). Regrowth occurred in 1.4% of the clipping group and 13.2% of the coiling group. Ischemic events were encountered in both groups; asymptomatic ones were higher in the coiling group (24.5%) than in the clipping group (2%), while symptomatic ischemic complications were equal (7.5%) in both groups. The deterioration of modified Rankin scale was detected totally in 13 UIAs (6.5%) with no statistical difference between groups. Postoperative hospital period was longer in clipping (P = 0.01). Conclusion: Clipping and coiling were both safe and feasible in the treatment of unruptured aneurysms. The clipping was advantageous in durability, while the rate of morbidity was lower, and hospitalization period was shorter in the coiling group. The clipping and coiling should coexist while complementing each other by understanding the advantages and disadvantages of both.

Objective: Cone-beam computed tomography (CBCT) images for skull base tumors provide detailed vascular information and localization in regard to surrounding bony structures. We report use of the CBCT fusion technique for skull base meningiomas. Methods: Six patients with petroclival or petrotentorial meningiomas supplied by multiple arterial systems were preoperatively evaluated using CBCT fusion imaging. Fusion images were reconstructed from three-dimensional rotational angiography with contrast agent injections from the internal carotid artery (ICA) and external carotid artery in 4 cases, vertebral artery and external carotid artery in 1 case, and ICA and vertebral artery in 1 case. Results: The feeding pedicles and tumor stains from 2 arterial systems were differentiated by separate colors. The courses and territories of the ICA dural feeders or ICA/vertebral artery pial feeders were easily distinguished from the external carotid artery dural feeders. Anastomoses between thin feeders from different arterial systems could be detected. Mixed stain (stain with both colors) was observed in some tumor compartments, suggesting dual supply from 2 arterial systems and the presence of peritumoral anastomoses. All patients underwent preoperative embolization without complications. Conclusions: CBCT fusion images clearly visualized the feeders from each arterial system, the vascular compartments within the tumor, and possible peritumoral anastomoses. This technique provides a substantial contribution to both preoperative embolization and surgical resection of skull base meningiomas.

Summary: Following technological advances in endovascular therapy, this approach is preferred over　surgery as the mainstay of treatment for dural arteriovenous fistula (dAVF). However, surgery remains important, and its role should be re-evaluated. In this retrospective study, we investigated the outcomes of surgical treatment for dAVF, focusing on the pitfalls of this approach in 101 patients who underwent surgery for dAVF. We analyzed the characteristics of lesions treated surgically, as well as treatment outcomes including the morbidity, AV shunt occlusion, and recurrence rates. The results included 20 patients who underwent only surgical treatment. The surgical morbidity rate was 5%. All AV shunts were extirpated at radical procedures; however, recurrence occurred in one patient. In conclusion, surgery serves as definitive treatment for specific types of dAVF. Careful decision-making regarding an endovascular vs. an open surgical approach is important, together with preparedness to manage the associated challenges, as observed in this case series.

脳ドック受診者1,200名を対象にMRIで発見される無症候性脳梗塞(ACI)と,び漫性白質病変(PVH)の臨床的意義を明らかにする目的で,危険因子(RF)と各所見の年齢層別分布を検討した.ACIのRFは高血圧(HT),糖尿病,加齢であり,PVHのRFは糖尿病を除きACIと一致した.RFのない群では,ACIを伴わないPVH及びPVHを伴うACIが加齢と共に増加していたが,HT群ではACIを伴わないPVHも減少し,PVHを伴うACIのみが増加した.HT群では,これらの所見が占める割合が有意に高く,しかも,10〜20年若年層にも認められた.更に,PVHを伴うACIは60歳以上で急速に増加した.以上から, 1)ACIとPVHは共通の背景因子を持つ, 2)PVHとACIの発生率に関する長期経過観察が必要である, 3)HTは,PVH及びACIのRFであり,その治療は60歳代迄に行うことが望ましいことが示唆された

BMS-191095, reportedly a selective mitoK(ATP) channel opener which is free from the known side effects of the prototype mitoK(ATP) channel opener diazoxide, induced acute and delayed preconditioning against glutamate excitotoxicity and delayed preconditioning against oxygen-glucose deprivation in primary cultures of rat cortical neurons. BMS-191095 dose dependently depolarized the mitochondria, increased the phosphorylation of PKC isoforms, but had no detectable effects on the activation of MAP kinases and did not influence the expressions of HSP70 and Mn-SOD. In BMS-191095-preconditioned neurons the glutamate-induced free-radical production was abolished. Our data give the first evidence that selective opening of mitoK(ATP) channels with BMS-191095 leads to remarkable neuroprotection via mechanisms that involve mitochondrial depolarization, PKC activation and attenuated free radical production during neuronal stress.

蝶形骨縁及び傍鞍部髄膜腫に関連する論文総数は68編(英文66編、和文2編)であり、髄膜腫発生部位ごとではclinoid:12編、sphenoorbital:8編、sphenoid wing:9編、parasellar:6編、tuberculum:24編、olfactory groove:9編であった。手術総数は2829例、全摘率は平均73.5%、再発率は平均9.02%、合併症発生率は平均37.2%、永続する合併症発生率は平均10.1%、手術関連死亡率は平均1.74%、傍鞍部髄膜腫の術後の視機能悪化率は平均10.4%であった。合併症としては、1)傍鞍部に存在する脳神経、動静脈、間脳下垂体に関わる合併症、2)脳損傷による合併症、3)脳脊髄液に関わる合併症、4)手術部位感染症、5)手術による後遺症状、6)周術期の全身性合併症に分類された。手術関連死では頭蓋内合併症より周術期の全身性合併症が多く、特に肺塞栓症が最多であり、死亡に至らない肺塞栓を含めて平均4.2%の発生率であった。

意識レベルがJapan Coma Scaleで3桁であった14例(男9例,女5例,平均47.4歳)を対象に,近赤外線分光分析装置で測定した総ヘモグロビン濃度に対する酸素化ヘモグロビン濃度の割合を,上腕部測定での値(TA)と前額部測定での値(TB)で比較した.その結果,大脳半球に障害が及んでいない3例のみ,TBがTAより高値であった.大脳半球に障害が及んだ11例中,2例を除いてTBが減少し,TAよりも低値であった.この2例では出血に伴う血管外のヘモグロビンの影響が考えられた.各種ヘモグロビン濃度変化或いは他の検査所見と比較したところ,虚血脳における酸素代謝障害を鋭敏に捉えていることが示された.又,TBが内頸静脈酸素飽和度とよく相関しながら変化する症例も認めた

重症頭部外傷で循環動態が安定していて重篤な合併症のなかった36例(2〜75歳,平均41±19歳)に低体温療法を施行し,入院時Glasgowコーマスケール(GCS),年齢,脳圧値,治療成績を解析し,低体温療法の適応を検討した.導入時の脳圧と膀胱温の平均値は44±14mmHgと36.2±1.4℃で,導入後は35±18mmHgと33.5±0.9℃で,導入後いずれも有意に低下した.導入後12例は脳圧のコントロールが良好となったが,24例は不能であった.入院時GCS4,5点の23例の死亡率は83%と高かったが,良好な結果を得たのは2歳と15歳の2例であった.GCS6,7点は13例で死亡率は54%で,良好な結果となった6例中5例が21〜27歳であった.脳圧亢進に対する低体温療法の転帰には年齢が大きく影響し,脳圧のコントロールが困難な小児例,若年例(特に入院時GCS6,7点)は低体温療法の良い適応となり得ることが分かった

脳虚血後には細胞内外の水分の移動のwater channelによる生理的制御が失われており,虚血後の細胞内外水分の移動はion channelにより移動するイオンに付随した形で受動的に行われているものと考えられた.water channelの詳細な病態生理学的な意義は不明なものの,脳虚血においては虚血後脳浮腫の進展になんらかの関与があるものと推察された

51歳男.ステロイドの効果が一過性であり視神経減圧術が著効した,視力障害で発症した肥厚性脳硬膜炎の1例.原因疾患の究明と平行して薬物療法を行い,その効果が認められない或いは,一過性であった場合,神経症状改善の為の直達手術を考慮すべきである

© 2019 Elsevier Inc. Background: Peripheral aneurysms are known to be a source of intracranial hemorrhage in patients with moyamoya disease. However, the natural history of ruptured peripheral aneurysms remains unclear. Some regress spontaneously, whereas others may rebleed. Direct treatments, such as surgical or intravascular treatment of the peripheral aneurysm, can have a risk of severe neurologic complications owing to the depth of the operative field and the fragility of the parent artery. A careful treatment policy is required. Case Description: In a 29-year-old man with moyamoya disease with intraventricular hemorrhage, rupture of a right anterior choroidal artery aneurysm was diagnosed by cerebral angiography. The aneurysm was approximately 4 mm in size and existed in the plexal segment of the right anterior choroidal artery. Endovascular embolization of the aneurysm was planned. However, repeat angiography 3 weeks after aneurysm diagnosis demonstrated complete resolution of the aneurysm. Such short-term disappearance of an aneurysm is remarkably rare. We believe that the aneurysm was thrombosed for a brief period considering the slow blood flow detected inside the aneurysm during the initial angiography. The patient was discharged with no neurologic deficit and has remained recurrence-free for >1 year. Conclusions: Given that spontaneous resolution of an aneurysm may occur in a short period of time, we suggest that conservative treatment be considered as an option for ruptured peripheral aneurysms associated with moyamoya disease when direct treatment is risky.

© 2018 National Stroke Association Background: Cerebral vasospasm is an uncontrollable and sometimes fatal complication occurring after subarachnoid hemorrhage. However, cerebral hyperperfusion syndrome is a rare complication after subarachnoid hemorrhage. Although plain computed tomography of cerebral hyperperfusion syndrome looks similar to cerebral infarction induced by cerebral vasospasm, they should be distinguished from each other because they require completely different treatments. Case Description: A 65-year-old man complained of severe headache and vomiting. A computed tomography scan of his head showed subarachnoid hemorrhage with acute hydrocephalus caused by intraventricular hematoma and aneurysm of the left middle cerebral artery. After endoscopic irrigation of the ventricular hematoma to decrease the intracranial pressure, we performed neck clipping for the ruptured aneurysm. We used a temporary clip to the proximal M1 segment twice for a total of 15 minutes. Five days after the clipping, a computed tomography scan of the patient's head showed a large low-density area in the left cerebral hemisphere. Although cerebral infarction caused by cerebral vasospasm was suspected, his perfusion computed tomography demonstrated a state of hyperperfusion corresponding to the low-density area. We started treatment to prevent vasodilation and excessive cerebral blood flow instead of treatment for cerebral vasospasm. After changing the treatment, the patient's symptoms gradually improved, and his perfusion computed tomography (8 days after surgery) showed no excessive increased blood flow. Conclusions: We present a case of cerebral hyperperfusion syndrome and its successful treatment, distinct from that of cerebral vasospasm, after ruptured aneurysm clipping. In addition, we discuss the mechanism of this rare syndrome based on previous reports.

© 2018 Elsevier B.V. Objective: The venous outlet of anterior condylar arteriovenous fistulas (AC-AVFs) often empties into the anterior condylar vein (ACV). Hypoglossal nerve palsy is one of the major complications after transvenous embolization (TVE) for the AC-AVF within the hypoglossal canal. However, no studies have investigated the route of the hypoglossal nerve within the hypoglossal canal in AC-AVF. The aim of the current study is to retrospectively verify the anatomical route of the hypoglossal nerve within its canal using dynamic computed tomography angiography (CTA) in order to facilitate the safe TVE for AC-AVF. Patients and methods: We included five patients with AC-AVF from 2011 to 2017. Dynamic CTA was performed on all patients. When the ACV was well-visualized by dynamic CTA, the hypoglossal nerve could be recognized as a less-intense structure within the surrounding enhanced vasculatures and the nerve route within the canal was analyzed. We also analyzed the location of the fistulas by digital subtraction angiography and cone-beam computed tomography. Results: In all five patients, the filling defect of the hypoglossal nerve ran through the most caudal portion of the hypoglossal canal. The fistulous pouches were located in the hypoglossal canal in three cases, and in the jugular tubercle venous complex in two cases. In all three cases with AC-AVF in the hypoglossal canal, the fistulous pouches were located in the superior wall of the hypoglossal canal, which means superior to the ACV. We performed TVE in four patients and none developed post-therapeutic hypoglossal nerve palsy. Conclusion: In the current study, dynamic CTA is useful for detecting the hypoglossal nerve within the hypoglossal canal. The hypoglossal nerve usually ran the bottom of its canal and the fistulous pouches were usually located at the superior aspect of the canal opposite side to the hypoglossal nerve. Accordingly, the selective embolization within the fistulous pouch located in the superior aspect of the ACV including jugular tubercle venous complex can reduce the risk of hypoglossal nerve palsy.

© 2018 Elsevier Inc. Background: Solitary fibrous tumors (SFTs)/hemangiopericytomas (HPCs) are highly vascularized tumors well known for malignant, invasive, and highly vascular features. To date, several studies have reported the preoperative imaging findings of SFTs/HPCs. In this study, computed tomography (CT) tumor values acquired from dynamic CT scan were selected to determine the tumor pathology of highly vascular tumors, such as SFTs/HPCs. Methods: We conducted a retrospective study on patients with pathologically diagnosed meningiomas and SFTs/HPCs who had undergone a dynamic contrast CT scan. We assessed and compared the CT values of these tumors according to the pathology. Results: From a total of 34 patients, 30 patients with meningiomas and 4 patients with HPCs were included. The mean CT values of SFTs/HPCs and angiomatous meningioma were statistically significantly higher than those of the other meningioma subtypes (P = 0.003). We also performed receiver operating characteristic curve analyses to detect an appropriate cutoff point for the CT value to differentiate tumor pathology, and the calculated threshold was 161 Hounsfield units (HU) (sensitivity, 100%; specificity, 75%; area under the curve, 0.87; 95%, CI 0.75–0.99). Conclusions: This study showed that obtaining a CT value is useful in determining highly vascular tumor pathology preoperatively. When considering neurosurgical extra-axial tumor removal, and when the CT value of tumors is >161 HU, then highly vascular tumors such as SFTs/HPCs or angiomatous meningiomas are likely, and this should be considered prior to surgical intervention and for risk assessment.