A new embolic material for brain arteriovenous malformations (AVMs)—Onyx liquid embolic system—has become available in Japan. We report our initial experience with surgical resection of AVMs after Onyx embolization and the pathological findings of the resected specimens.
AVMs of three patients were embolized with Onyx followed by surgical resection. A high rate of Onyx penetration into the nidus was obtained when the plug of Onyx was formed around the tip of the microcatheter navigated as closely to the nidus as possible. Otherwise, Onyx injection resulted in partial occlusion of the nidus or proximal occlusion of the feeders. Total resection of the nidus was safely achieved in every case. The plane of dissection between the brain and the embolized nidus that demonstrated a firm consistency was easily identified. Uncontrollable bleeding from the perinidal capillary network was rarely encountered. Pathological examination did not show angionecrosis in the walls of the embolized vessels. Infiltration of macrophages was observed in the embolized vessels in the specimens resected more than five days after embolization.
Onyx embolization followed by surgical resection is a safe and effective treatment for AVMs.

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Background: Rupture of cerebral aneurysms results in subarachnoid hemorrhage. We previously reported that bleeding from cerebral aneurysms can arrest from outside, but bleeding from some aneurysms arrests in different ways.
Methods: Between 2007 and 2011, we prospectively investigated mechanisms of spontaneous hemostasis in ruptured aneurysms by histopathological examination on the specimens of the aneurysm wall, including their rupture points harvested after surgical clipping.
Results: Hemostatic mechanisms were investigated in 77 patients with ruptured aneurysms (21 men, 56 women; age range, 34–87 years). Hemostatic patterns were divided into three different patterns depending on the location of clot formation. In 26 aneurysms (34%), the surface of the aneurysm rupture point was sealed from the outside by clot (outside pattern). In 35 aneurysms (45%), thrombus was attached to the rupture point from inside the aneurysm (inside pattern). In 12 (16%) cases, thrombus extended from inside to outside of the rupture point (inside-outside pattern). In a small number of aneurysms (5%), the rupture point was changed to a fibrin wall like a membrane without a distinct thrombus formation (membrane pattern). These hemostatic patterns demonstrated no correlation with clinical profile of the patients, bleb formation, or aneurysm size. Thinning and fragmentation of aneurysm wall were seen predominantly in the inside and inside-outside pattern (p<0.01) as compared to the outside pattern.
Conclusion: Intra-aneurysm thrombus formation was seen in approximately 61% of ruptured aneurysms. This must be kept in mind when ruptured aneurysms are treated surgically.

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In this population-based study, we evaluated the changes of case-fatality rates and full-recovery rates in subarachnoid hemorrhage at three months and determined trends in these rates during the period of 1993–2009. We retrospectively reviewed 4,308 patients registered in the Nagasaki SAH Data Bank from 1993 to 2009. All neurosurgical units in Nagasaki Prefecture participate in Nagasaki SAH Data Bank. From 1993 to 2000, case fatality rates were 25.5%, 29.8%, 37.1%, and 51.2% in patients at ages 40–59, 60–69, 70–79, and ≥80 years, respectively. Whereas, from 2001 to 2009, these rates improved to 20.0%, 20.0%, 27.4%, and 39.2%, respectively. There were significant differences in all age groups. On the other hand, there were no significant changes in full-recovery rates between 1993–2000 and 2001–2009. The proportions of high grade SAH (Hunt & Hess Grade IV and V) and low grade SAH (Hunt & Hess Grade I and II) did not differ significantly in all age groups between 1993–2000 and 2001–2009. In all age groups, rates of radical treatment, especially with coil embolization, for ruptured aneurysms increased significantly in 2001–2009.
Advances in radical treatment and intensive management might reduce mortality in SAH but might not result in improvement of full-recovery rates at three months. Long term follow-up studies are required to accurately evaluated the favorable outcome of severe SAH.

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Background: Intracerebral hemorrhage (ICH) associated with antiplatelet-therapy (AP) and with anticoagulant-therapy (AC) is becoming more common as the use of these medications increases in the aging population. The effect of preceding AP and AC on outcome after ICH has not been adequately investigated. We evaluated mortality and hematoma enlargement in patients with ICH to determine the influence of AP or AC on prognosis of patients with ICH.
Methods: We identified all patients hospitalized with ICH in a single center from October 2008 through September 2009 and evaluated their clinical characteristics and outcomes from hospital records.
Results: There were 156 consecutive patients with ICH, including 22 patients treated with AP and 19 with AC. Two of these patients received both AP and AC. The AP group and AC group were compared with the group of no-antiplatelet-or-anticoagulant-therapy (NT). Mortality in the AP group (36%) and AC group (42%) was higher than that in the NT group (14%). A multivariable analysis showed that AP and AC were independently associated with mortality. The initial ICH volume was greater in the AP group, and hemorrhage expansion occurred more in the AC group. Thus a higher rate of mortality was indicated in these groups. Furthermore, the rates of thrombotic events were higher in the AP group and AC group.
Conclusion: We showed poor outcomes and increased mortality in patients treated with AP and AC. Further studies will be required to identify effective treatment to prevent hemorrhage expansion and thrombotic events.

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The treatment strategy for carotid stenosis in patients >80 years has been changing following many clinical trials. We retrospectively examined the surgical results of carotid stenosis in octogenarians in our hospital. Between January 2004 and November 2010, 223 patients underwent 143 carotid endarterectomies (CEA) and 80 carotid angioplasties with stentings (CAS) in our hospital. We regarded MRI plaque imaging using black-blood T1 sequence as important to select the treatment strategy.
Nineteen octogenarian patients underwent nine CEA and 10 CAS. MRI plaque imaging revealed that relative overall signal intensity of carotid plaque was significantly higher in the CEA cases than in CAS cases. Perioperative and long-term stroke, myocardial infarction and death rates did not differ significantly between the two treatment groups.
Our strategy using MRI plaque imaging for carotid stenosis in octogenarians is useful.

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Objective: To assess management techniques for residual and recurrent lesions of embolized ruptured intracranial aneurysms, we present a consecutive series of 12 patients who underwent additional treatment using endovascular or surgical techniques.
Methods: We treated 144 patients with ruptured cerebral aneurysms by coil embolization over a period of four years. Follow-up angiography or magnetic resonance angiography was obtained every six months postembolization for 105 patients. Patients presenting with rapid increase of residual and recurrent lesions, those larger than 30% of the original lesion, or those that had blebs underwent additional treatment using both endovascular and surgical techniques. The choice of additional treatment was determined by angiographic findings of framing coils previously embolized and remnant necks.
Results: During the follow-up period, 12 patients underwent additional treatment. Five patients were treated by coil embolization, and seven by surgical clipping. There were no neurological complications in the 12 patients who underwent additional treatment.
Conclusions: Management of residual and recurrent lesions of embolized ruptured cerebral aneurysms requires careful follow-up using neuroimaging modalities, active decisions for additional treatment, and proper choice of treatment using both endovascular and surgical techniques. Under this management, additional treatment can be performed safely.

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Wide-necked intracranial aneurysms are difficult to obliterate by coil embolization without adjunct techniques. Clipping is still an important technique in the endovascular era. We restrospectively analyzed the characteristics of the clipping techniques of wide-neck intracranial aneurysms. Between April 2008 and October 2010, six wide-necked intracranial aneurysms of 50 asymptomatic unruptured intracranial aneurysms were treated with clipping. One case was an anterior communicating aneurysm, one was a distal anterior cerebral artery aneurysm, one was a middle cerebral artery aneurysm, and three were paraclionoid aneurysms. The maximum diameter of these aneurysms was 20 mm. The average neck diameter was 9.5 mm. There was no neurological morbidity or mortality. The clipping techniques were (1) decompression of the aneurysm with the proximal control, (2) peeling off the aneurysm body from around the structures, (3) using the multiple clipping to prevent the slip-out, (4) clipping in parallel with the parent vessels.
In clipping for wide-necked intracranial aneurysms, these techniques are useful and safe. More outcome studies comparing coil embolization and clipping for wide-necked intracranial aneurysm are required.

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We report an 80-year-old male with posterior cranial fossa “extrasinusal type” dural arteriovenous fistula (dAVF) presenting with subarachnoid hemorrhage (SAH) and subsequent rebleeding. He complained of sudden occipitalgia. Although head computed tomography (CT) scan revealed SAH localized to the right cerebello-pontine cistern, neither internal carotid angiograms nor vertebral angiograms showed any vascular abnormalities. He presented with sudden headache again and slight disturbance of consciousness four days after the onset of headache. A repeated CT scan revealed SAH due to rebleeding. Right external carotid angiograms showed a dAVF which was fed mainly by the middle meningeal artery and the occipital artery, and draining directly into the petrosal vein. The draining vein had a varix that was thought to be the bleeding point. The patient underwent surgical interruption of the draining vein. Postoperative angiograms showed complete obliteration of the fistula.
The petrosal vein-draining dAVF, which is an “extrasinusal type” dAVF according to Lasjaunias’ classification, presents a high risk of intracranial hemorrhage. Therefore, they should be completely cured with surgical interruption of the retrograde venous drainage as early as possible.

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We present a rare case with a ruptured aneurysm of a distal anterior cerebral artery that was adjacent to an anterior communicating artery aneurysm. A 59-year-old male suddenly developed headache and dizziness, and was conveyed to our hospital. Plain CT scans revealed subarachnoid hemorrhage and intracerebral hematoma that was distributed in the right frontal lobe. CT-angiography demonstrated two aneurysms. One was found at A2 segment of right anterior cerebral artery, and the other was found at the anterior communicating artery. The aneurysms came in contact with each other. Because anterior cerebral artery aneurysm had a broad based neck, neck clipping of both aneurysms was performed. It is important to get the A1 segment of proximal to both aneurysms in this case, so we chose a basal interhemispheric approach. This approach provides a wide operative view that improves surgical safety. The postoperative course was uneventful.
In this paper, we discuss the strategy of adjacent aneurysms between the distal anterior cerebral artery and anterior communicating artery.

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A 54-year-old man with a pulsatile mass on the right side of his neck suffered left hemiparesis due to cerebral infarction in the right cerebral hemisphere. Three-dimensional computed tomographic angiography revealed an aneurysm located at the origin of the right cervical internal carotid artery (ICA). On magnetic resonance (MR) imaging, the aneurysm included fresh and organized thrombi. Under intraoperative monitoring of transcranial Doppler (TCD), transcranial cerebral oxygen saturation (cSO₂) and electroencephalogram (EEG), the aneurysm was removed and the right common carotid artery (CCA) and ICA were anastomosed using interposition graft of expanded polytetrafluoroethylene. Attempts were made to keep systolic blood pressure during surgery above a +10% increase. Microembolic signals developed on TCD during dissection of the aneurysm, and then the CCA was early clamped. Transcranial cSO₂ on the right forehead and EEG showed no abnormal change throughout surgery. Postoperatively, MR imaging revealed two asymptomatic spotty ischemic lesions, and the patient had only hoarseness.
The present case suggests that intentional hypertension and monitoring of TCD, transcranial cSO₂ and EEG during surgery might minimize development of intraoperative ischemic events due to embolism from the surgical site and carotid clamping.

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Ideally, small branches originating from a recipient should not be cut to obtain enough length for direct anastomosis in moyamoya disease. When these branches are near each other and a temporary clip is used to occlude a recipient and these branches, simultaneously, troublesome bleeding may occur just after opening of the recipient. In this situation, an additional clip is applied to the small branch, which has already been clipped with the first clip. But even after the procedure, bleeding may continue. In the present study, I introduce a technique to overcome this problem. The new technique is as follows: A micro-needle with an 11-0 monofilament was passed through a scalp artery in the usual fashion. After completion of the procedure, a 1 ml syringe including physiological saline with a dull-tip needle was held in the left hand, and the tip of the dull-tip needle was introduced into the inner lumen of the recipient though its orifice. Then, the dull tip of needle was used to slightly push the bottom of the inner wall of the recipient. Continuous irrigation was started to find an edge of the orifice of the recipient. After the edge was clearly defined, the micro-needle held in the right hand was passed through the recipient. The process was repeated until completion of the anastomotic procedure. The procedure required less time than the usual technique.
The pushing/irrigation technique effectively countered continuous bleeding from an orifice of a recipient during direct anastomosis. The use of this technique during the anastomotic procedure can reliably and safely contribute to the treatment of moyamoya disease.

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