We report our preliminary experience using radial artery graft bypass in patients with ruptured internal carotid artery aneurysm. The following types of 12 ruptured internal carotid artery aneurysms were treated: dorsomedial aneurysms with ill-defined necks (in 8 patients); tiny paraclinoid aneurysms projected in the superior (n=1) and ventral (n=1) direction; fusiform aneurysm (n=1) located between the C1 segment and M1 segment; and an IC-PC aneurysm (n=1) previously clipped 15 years before. Bypass procedures employed were EC-radial artery-M2 bypass in 6, and temporary using RA-M2 bypass (i.e., forearm vascular pedicle) in 6. Complete obliteration of aneurysms with no ischemic complication was achieved in all dorsomedial internal carotid aneurysms. Graft failure occurred in 1 case. Our experience emphasizes the importance of achieving vascular anastomosis in various clinical settings. We also describe a proposed strategy to obliterate blister aneurysm.

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The radial artery and saphenous vein have been used as a useful free graft for neurosurgical revascularization surgery. Potential disadvantages of the radial artery compared with the saphenous vein include relative shortness, spasm, and functional occlusion.
To compensate for the short length of the radial artery graft, the radial artery and the superior thyroid or occipital arteries were connected end-to-end. This method was applied in 3 cases of unclippable aneurysms, achieving adequate revascularizations. There were no complications related to this procedure.
Radial artery graft bypass using the superior thyroid or occipital artery is a simple, safe, and useful method for cerebral revascularization.

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As most of cerebral arteriovenous malformations (AVMs) and dural AVMs (dAVM) are electively treated, their urgent treatment has been rarely reported. We therefore sought to evaluate the clinical characteristics and treatment strategy for comatose patients with AVM/dAVM transported by ambulance. Within the past 10 years, 36 patients with AVM/dAVM (30 AVM and 6 dAVM, 21 men and 15 women with an average age of 48.6 years) have arrived at our institution. Among these, 23 patients had a Glasgow Coma Scale (GCS) grade of 6 or less and 16 patients presented with pupillary abnormality.
The average amount of intracerebral hematoma was 44.2 ml. The AVM was removed after cerebral angiography in 19 patients, whereas 8 underwent hematoma evacuation and 3 underwent ventricular drainage prior to angiography. An AVM was simultaneously extirpated in 6 patients at the initial craniotomy without angiography, 4 of which were preoperatively diagnosed as hypertensive cerebral hemorrhage. The Spetzler-Martin Grade was I in 9, II in 16, III in 4 and V in 1 patient, respectively. The AVM/dAVM was extirpated in 32 patients. The average time from arrival to emergency surgery was 213 minutes. Massive cerebral hematoma tended to be caused by small AVM. Their modified Rankin Scale assessed at discharge was 0 in 3, 1 in 6, 2 in 2, 3 in 1, 4 in 4, 5 in 12, 6 in 6 patients, respectively. Poor outcome was related to older age, poor GCS and Apache II score, and large amount of hematoma volume.
Prompt resuscitation and surgical decompression along with neurointensive care appeared to be mandatory to save these AVM/dAVM patients showing impending herniation.

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We retrospectively studied 15 patients, 9 men and 6 women aged 17 to 52 years (mean 28.1 years), who developed cyst formation following gamma knife radiosurgery (GKS) at our hospital for cerebral arteriovenous malformation (AVM). The mean nidus volume was 11 cm³ (0.1-26.7 cm³), and the mean prescription dose at the nidus margin was 20.0 Gy (18-28 Gy). Nidus obliteration was obtained in 9 patients, partial obliteration in 5, and no change in 1. Cyst formation was detected from 2.5 to 13.5 years (mean 6.4 years) after GKS. Three patients underwent craniotomy, and 2 received placement of an Ommaya reservoir. Spontaneous regression of cyst was observed in 2 patients. The outcome of the cyst was unknown in 2 patients, because of no response from the neurosurgeon the patients were referred to. Serial magnetic resonance imaging was performed in the other 6 patients because the cyst size was stable or asymptomatic. These findings suggest that cyst formation following GKS is not a “late complication.”
Placement of an Ommaya reservoir or cyst-peritoneal shunt is recommended for cysts with obliterated nidus. Craniotomy should be considered if the nidus is not completely obliterated or the cyst is associated with an expanding hematoma. Serial follow-up imaging is recommended for asymptomatic patients.

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Tentorial dural arteriovenous fistula (AVF) is an aggressive lesion causing intracranial hemorrhage, venous infarction, and progressive neurological deficits because it drains only the leptomeningeal vein. Though treatment options include surgical interruption of the draining vein or excision, stereotactic radiosurgery, endovascular procedure, and a combination of these options, optimal treatment has not been established. We report on 5 patients with tentorial dural AVFs treated by endovascular procedures. One patient presented with a progressive neurological deficit, 1 with subarachnoid hemorrhage, 1 with venous infarction, and 2 patients were incidentally discovered. All patients were treated with transarterial embolization using NBCA (n-butyl cyanoacrylate). In 1 patient with high flow fistula, coils were placed in the varix before NBCA injection to prevent excessive migration of NBCA into the draining vein. Immediate complete obliteration was achieved in 1 patient. In 3 of 4 patients with residual shunt, complete obliteration was confirmed by follow-up angiography. Transarterial embolization using NBCA for tentorial dural AVF is safe and effective, and can be a treatment of choice.

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Dural arteriovenous fistula (DAVF) with sinus occlusion and cortical reflux often presents with neurological symptoms. These symptoms are due to venous congestion and hypertension that often result in intracranial hemorrhage and venous infarction. We investigate 25 patients (9% of all our DAVF cases) including 19 males and 6 females aged from 46 to 79 years old with brain dysfunction due to marked venous reflux from DAVF. The lesions were located in the lateral sinus in 17 patients, the superior sagittal sinus in 2, the tentorial sinus in 3, and other locations in 3 cases. Clinical manifestations included hemorrhage with various neurological deficits in 10 patients and brain dysfunction due to venous congestion in 15 patients, including 7 with visual disturbances, 5 with cognitive dysfunction or dementia, 4 with convulsions, and 3 with other symptoms.
Twelve patients were treated with transarterial embolization (TAE), 10 with transvenous embolization and 3 with surgical sinus packing. Sinoplasty with balloon catheter was performed in 3 patients. Angiographically, the fistula was totally occluded in 16 patients, almost completely occluded in 7 and only partially occluded in 2. TAE with glue showed a high cure rate (70%). Symptoms improved or recovered in 18 patients. However, symptoms did not change in 3 patients, including 1 with pre-operatively severe neurological deficits and 2 with visual disturbance untreated for a prolonged time or treated palliatively. We found that there were 2 venous reflux patterns to the cortical vein in cases of DAVF. They include reflux to the cortical vein as the only drainage route from the isolated sinus, and retrograde flow through the sagittal sinus due to the bilateral occlusion of lateral sinus resulting in pancerebral vascular congestion. The former represented the aggressive type and showed focal venous congestion and required early occlusion of shunt flow. The latter showed more chronic progression with cognitive or psychological dysfunction requiring reconstruction of the drainage pathway as well as shunt occlusion. These treatments should be performed as early as possible to avoid irreversible damage to the brain.
Although treatment strategy should be selected according to the location of each DAVF and its possible approach, transarterial target embolization using liquid embolic materials is promising due to its high cure rate.

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We analyzed the outcome of patients over 80 years old with subarachnoid hemorrhage (SAH). We conducted a retrospectively evaluated the medical records and imaging studies of 49 patients treated with clipping, coiling or conservative therapy between January 2005 and December 2008. The patients were graded on admission, according to the World Federation of Neurological Surgeons (WFNS) grade, and modified Rankin Scale (mRS) at discharge.
Forty-nine patients ranged from 80 to 94 (average 85.8). Seven patients were men. The WFNS grade on admission revealed that 14 patients were Grade 1, 8 Grade II, 4 Grade III, 6 Grade IV and 17 Grade V. Fourteen patients underwent surgical clipping, and 10 patients underwent coil embolization. Twenty-five patients recrived conservative therapy. The overall results evaluated as mRS at discharge were: 3 patients (6.1%) were mRS 0, 4 (8.2%) mRS 1, 4 (8.2%) mRS 2, 4 (8.2%) mRS 3, 10 (20.4%) mRS 4, 13 (26.5%) mRS 5, 12 (24.5%) mRS 6. While only 1 patient (4.2%) in the conservative group had a favorable outcome (mRS 0-3), 13 patients in the operative group (54.2%) had favorable outcomes: 8 patients (80.0%) who underwent coil embolization and 5 patients (35.7%) who underwent surgical clipping. Unfavorable outcomes were caused mainly by primary brain damage and symptomatic vasospasm.
In elderly SAH patients, radical treatment of ruptured aneurysm is important to achieve a favorable outcome.

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Large thrombosed aneurysms are highly associated with poor prognosis because of the compression of surrounding tissue by the enlarged aneurysm or a high risk of rupture. Treatment of this condition is also often difficult. Some clinicians select endovascular surgery in cases in which it is difficult to perform direct surgery, though the procedure is not an optimal treatment option for thrombosed aneurysms. We reviewed 10 patients with thrombosed aneurysm who received endovascular surgery in our department between January 1997 and December 2007. Their age range was 41 to 80 years (mean 60.9 years, M:F=2:8). Five patients had a lesion in the internal carotid artery and the other 5 in the posterior cranial fossa. Initial symptoms at onset included cranial nerve symptoms in 4, acute headache in 2, visual field defect in 1, subarachnoid bleeding in 1, and 2 were incidental cases. Seven of these patients were treated by intrasaccular embolization and 3 were treated by parent artery occlusion. In the 7 patients treated by intrasaccular embolization, 5 had a relapse after the coil was sunk into the thrombus and 3 underwent re-embolization. Symptomatic improvement was observed following embolization in all 4 patients with symptomatic unruptured aneurysms. One patient died of brain stem compression caused by aneurysm growth. In 3 patients treated by parent artery occlusion, symptomatic improvement was observed in 1 and visual field defect worsened in 1 patient. One patient died of ruptured basilar artery aneurysm 3 days after the occlusion of 1 vertebral artery.
Endovascular surgery may not be the best option for large thrombosed aneurysms. However, these treatment outcomes suggest that endovascular surgery is a treatment option for those in whom it is difficult to provide neck clipping who require rupture prevention and a short-term or temporal improvement in symptoms.

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We examined how the effects of antiplatelet agents changed after their discontinuation before surgery in terms of platelet aggregation capacity. The study population comprised 35 patients with cerebral ischemia who were about to undergo cerebrovascular reconstruction surgery (Carotid EndoAtherecyomy; 22 patients underwent CEA, and 13 underwent STA-MCA bypass surgery). Preoperatively, they received aspirin (22 patients), clopidogrel (9 patients), or cilostazol (4 patients). The antiplatelet agents were discontinued 3-4 days before surgery and restarted on the day following surgery. On the day of surgery, the percent change rate of the maximum platelet aggregability rate increased to 130% compared with the level during the antiplatelet therapy in the patients receiving aspirin, but it remained as low as 32% in the patients receiving clopidogrel. Almost all patients resumed their pre-discontinuation levels of platelet aggregation after the restart of antiplatelet therapy. None of the 35 patients experienced difficulty in hemostasis during surgery or cerebral infarction or myocardial ischemia during or after surgery.
The changes in platelet aggregation rate observed with the use of a selected appropriate inducer reflected patient statuses after discontinuation and restart of antiplatelet therapy. This may be a useful index for monitoring patients undergoing cerebrovascular reconstruction surgery.

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An 80-year-old male presented with a subarachnoid hemorrhage of Hunt and Kosnik Grade IV. Cerebral angiography revealed a large eccentric fusiform aneurysm arising from the lower portion of the basilar artery just distal to the right anterior inferior cerebellar artery. We decided to surgically treat the ruptured basilar artery aneurysm in the acute stage via a right retromastoid suboccipital approach. Before the operation, we guided a balloon catheter into the left vertebral and right carotid arteries. Intraoperatively, we applied a temporary clip to the right vertebral artery. After exposing the aneurysm, we temporarily inflated the occlusion balloon within the left vertebral and right internal carotid arteries. After suction decompression from the left vertebral artery, we used Sugita’s long clip to clip the neck parallel to the basilar trunk. Bradycardia occurred, but the heart rhythm recovered immediately after the recanalization of these arteries. Intraoperative digital subtraction angiography showed obliteration of the aneurysm and preservation of basilar artery patency. The patient gradually recovered consciousness after being in a comatose state for 10 hours after surgery. It is possible to directly clip a large basilar trunk aneurysm. The clipping tends to be done in the same direction as the operative approach. Therefore, the operative approach should be parallel to and should preserve the basilar artery. The intraoperative endovascular technique (using temporary balloon occlusion) and intraoperative digital subtraction angiography can contribute to gaining proximal artery control and verifying basilar artery patency. Clipping is much easier when using suction decompression. However, temporary balloon occlusion should be done as quickly as possible.

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Limb shaking is a rare symptom of transient ischemic attack (TIA), and it is sometimes misdiagnosed as partial seizure. The pathological mechanism of the limb shaking remains unknown. I present a case of a 58-year-old man with crescent limb shaking TIA, caused by the severe right internal carotid artery stenosis. After the emergent carotid endarterectomy (CEA) was performed, the limb shaking TIA disappeared. Limb shaking TIA should be treated like a standard TIA.

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