The efficacy of and indications for urgent carotid endarterectomy (CEA) and carotid artery stenting (CAS) in patients with acute stroke have not been established. The purpose of this study was to retrospectively compare the peri-procedural outcomes and complications of urgent CEA and CAS after acute ischemic stroke in patients with high-grade stenosis of the internal carotid artery at a single center.
Urgent CEA was performed for 11 patients (mean age: 66.5±8.0 years, 91% male) and CAS for 25 patients (mean age: 73.4±10 years, 84% male). Neurologic examinations were performed before and after treatment. A decrease of more than four points on the NIHSS score was considered as improvement. Peri-procedural mortality and morbidity of urgent CEA were 0% and 0%, respectively, and those of CAS were also 0% and 0%, respectively. Although the incidence of symptomatic cerebral hyperperfusion after revascularization was 9% in CEA and 4% in CAS, no hemorrhagic transformation was detected. NIHSS improved were 10% in patients who underwent CEA and 40% in patients who underwent CAS. Ten patients (91%) who underwent CEA and 18 patients (72%) who underwent CAS had favorable outcomes (modified Rankin Scale score<3) at 90 days.
Urgent CEA and CAS can be performed safely with low peri-procedural mortality and morbidity rates with careful patient selection and peri-operative management.

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Surgical resection of cerebral arteriovenous malformations (AVMs) is a certain but difficult treatment because of its complicated pathology and the sometimes limited experience of the neurosurgeon. Therefore, care in deciding the surgical indication and strategy is essential. We report three cases of AVMs from the viewpoint of an inexperienced neurosurgeon. Preoperative embolization was performed in all cases, while in one patient there was a hemorrhagic complication causing neurological deterioration. All AVMs were extirpated with established techniques and procedures. For a beginner in AVM surgery, the proper selection of cases was thought to be most important. As for the surgical technique, extensive opening of the sulci and fissures, proximal control by temporary clip application on feeders and blunt dissection of the nidus without coagulation were indispensable.

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Single-fraction stereotactic radiosurgery (SRS) is effective for small volume arteriovenous malformations (AVMs). However, large AVMs, and AVMs in eloquent regions are often not cured with SRS, because we cannot give an adequate dose to the AVMs without causing radiation damage to the surrounding normal brain tissue. We have used hypo-fractionated stereotactic radiotherapy (HFSRT) including SRS with Cyberknife (CK) for these AVMs in eloquent regions or large volume AVMs. The aim of this study is to evaluate the effectiveness of our HFSRT including SRS with CK for these AVMs with possibly a lower complication rate.
During the past six years, single-fraction SRS was used as a basic treatment method for AVMs located in non-eloquent regions or for small volume AVMs. We have treated 36 cases (17 males and 19 females) of large AVMs and AVMs in eloquent regions with HFSRT, including SRS using CK. The age ranged from seven to 66 years (average 33 years). A mean marginal dose of 27 Gy (range 16–30 Gy) was prescribed and the average isodose was 76% (range 64-86%) isodose. Most patients were treated with the HFSRT method (three to five fractions) except for six SRS cases. 3-D SPGR MRA was performed with a 3T MR scanner (Signa HDX 3.0T, GE, US). The time-dependent relative decay of the trans-nidal blood flow and sequential volumetric reduction evidenced by 3D SPGR MRA was referred to as “obliteration dynamics.” All patients had periodical follow-up studies at regular intervals. Subtotal obliteration was determined if the residual nidus volume was 5% or less of the initial nidus volume.
The mean follow-up period was 37 months (6–53). All patients tolerated the procedures well. After the treatment, a significant obliteration dynamics was observed in all patients over a 12-month follow-up. Subtotal obliteration was obtained in 11 patients out of 18 (61%) who had over 24-month follow-up. In conjunction with the gradual reduction of AVM volume after CK treatment, visual field defects improved, motor functions recovered and easy medical control of symptomatic epilepsy was realized in a significant number of cases.
HFSRT with CK was found to be safe and effective. The use of sequential 3D SPGR MRA at 3T enables a noninvasive quantitative assessment of the dynamic obliteration process induced by HFSRT with CK in AVMs. If the long term follow-up sustains these preliminary results, HFSRT with CK could become the first treatment of choice for large AVM and eloquent regions.

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The main aim of the treatment of ruptured cerebral arteriovenous malformations (AVMs) is to prevent rebleeding. We analyzed the rate and the timing of re-hemorrhage of ruptured cerebral AVMs in a consecutive series of patients admitted to our institute. The total number of patients was 127 (79 males, 48 females), admitted in our university hospital from 1979 to 2009. Hemorrhagic and non-hemorrhagic presentation was recorded in 68 and 59 cases, respectively. The AVMs were diagnosed with catheter angiography, magnetic resonance imaging or enhanced computed tomography. Spinal AVM, dural arteriovenous fistula, cavernous malformation and venous angioma were excluded.
The data of patients admitted to our hospital before 2008 were searched retrospectively, whereas data from patients admitted from 2008 and later were subjected to prospective tracing surveys, and the location of nidi, treatment modality, timing of hemorrhage after the onset and neurological outcomes were investigated. We specially focused on the re-hemorrhagic rate in the acute phase and analyzed the data minutely. Re-hemorrhagic risk decreased 400 days after the first hemorrhage and became constant. Re-hemorrhage during the follow-up period seems to be one of the causes of neurological deterioration, but re-hemorrhage in the acute phase did not result in a significant incidence of mortality.
Early re-hemorrhage of cerebral AVMs was not considered as frequent or catastrophic as ruptured aneurysms. Our clinical data support our treatment strategy of avoiding aggressive early treatments for ruptured cerebral AVMs.

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We retrospectively analyze of our experience with unruptured thrombosed large (TL) vertebral artery (VA) aneurysms and strategies for their treatment. From January 2006 to November 2011, 11 patients with a TLVA aneurysm of more than 15 mm in diameter were treated by open surgery. Various techniques are required to revascularize a posterior cerebellar artery (PICA) or a VA itself, preserve of perforating arteries arising from an aneurysm and resect an aneurysm with a mass effect. In the case of patients without a contralateral VA, when an occlusion of the parent artery is needed, a high flow bypass such as a V3-radial artery (RA)-P2 bypass should be considered. In case of PICA involved aneurysms, an occipital artery (OA)-PICA bypass is required. Basically, trapping of the TL aneurysm is recommended to prevent regrowth. However, contrived proximal clipping is thought to be suitable for some asymptomatic TL aneurysms, which themselves exhibit perforating arteries. As for symptomatic TL calcified aneurysms manifesting a mass effect, the aneurysm should be resected because we cannot necessarily expect shrinkage even after aneurysmal thrombosis. When resecting a TL calcified aneurysm, it is desirable to leave a part of the aneurysmal outer shell adhered to surrounding structures. One patient was treated with an OA-V4 bypass and aneurysm resection. The V4 bypass supplied anterograde blood flow for the basilar artery, substituting for a V3-RA-P2 bypass. The results of the 11 patients on the modified Rankin Scale assessed at present were 0 in 4, 1 in 4, 2 in 1, and 3 in 2, respectively. Poor outcome is related to perforating injuries. Regrowth or bleeding from the aneurysm has not been observed.
It is important to perform an uncompromising therapy for the patient of a TLVA aneurysm, so several techniques must be mastered.

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Surgical management of complex vascular diseases including giant carotid aneurysm, ruptured internal carotid artery anterior wall aneurysms, and carotid cavernous fistulae remains controversial, with direct, reconstructive, or endovascular surgery with parent artery preservation still presenting difficulties. Radial artery grafts (RAGs) have been used in the treatment of complex vascular lesions.
We examined perioperative complications and the surgical technique to prevent complications after RAGs for management of these difficult lesions. We retrospectively investigated 81 consecutive patients (65 females; 17 to 78 years) treated between September 1997 and January 2012, in whom RAGs were used, for postoperative outcomes and complications. Postoperative complications including epidural hematoma, symptomatic seizures, and cranial nerve palsy were confirmed.
Although it cannot be stated that the frequency of perioperative temporary complications of RAGs was low, the final outcomes were favorable. Even in complex vascular diseases, RAGs would appear to be a useful and safe treatment.

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Carotid plaque constituents such as hemorrhage, lipid core, fibrosis, and calcification are important factors in predicting the clinical outcome of carotid artery stenting (CAS). Magnetic resonance imaging (MRI) can noninvasively assess changes in carotid plaque composition by evaluating the Sp/Sm ratio calculated with the signal intensity of carotid plaque (Sp) compared to that of sternocleidomastoid muscle (Sm) using the black-blood technique.
In the current study, we assessed the effects of 5 mg rosuvastatin and 1,800 mg eicosapentaenoic acid (EPA) on carotid plaque composition and volume using MRI and intravascular ultrasound prior to CAS. Thirty consecutive patients with atherosclerotic carotid stenosis were randomly divided into two groups—an EPA/rosuvastatin group (n=15) and a control group (n=15)—and then were treated with CAS. Perioperative complications and postoperative high spotty lesions on diffusion weighted image (DWI) were compared between the two groups. As a result, EPA and rosuvastatin significantly reduced the Sp/Sm ratio in both T1- and T2-weighted images in patients with unstable plaques (T1; p=0.021, T2; p=0.014). Plaque volume was also reduced between baseline and follow-up in 4 of 15 cases treated with EPA/rosuvastatin. The number of postoperative high spotty lesions on DWI significantly decreased in the EPA/rosuvastatin group (13%; 2/15) compared with the control group (40%; 6/15, p<0.05), whereas no significant difference was observed in perioperative complication rate.
The combined therapy of EPA and rosuvastatin leads to a benefical effect on plaque composition and volume, which may contribute to reducing the ischemic complications with CAS, particular in patients with vulnerable plaque.

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Splitting of the sylvian fissure is the gateway for a neurosurgical beginner in microsurgery. Techniques for splitting the sylvian fissure have varied among neurosurgeons partly due to a paucity of objective data in the literature. We focused on the point along the sylvian fissure in the apex of the pars triangularis of the frontal operculum, where the subarachnoid space is reported to be relatively large and appears appropriate for the starting point of splitting the sylvian fissure. In practice, the distance from this point to the frontal base along the superficial sylvian fissure is compared between the data of preoperative 3D-CT angiography (3DCTA) surface images and that of the operative view. In both methods, anatomical identification of the pars triangularis and adjacent structures is almost definite except for cases presenting with subarachnoid hemorrhage. There is a significant correlation between them, indicating a favorable place to start splitting the sylvian fissure is approximately 31 mm distal from the frontal base. Moreover, the bifurcation of the middle cerebral artery was situated at the approximate bisect point in the line connecting the starting point with the frontal base. We concluded that preoperative 3DCTA surface image is a feasible and reliable method to determine the starting point of splitting the sylvian fissure.
We also report the importance of epiarachnoidal dissection through a subfrontal approach combined with standard subarachnoidal splitting, especially if one wishs to safely dissect severely adhesive and interdigitated parts. In most cases, a part that is hard to split is encountered, just before the M1 segment in the sphenoidal compartment of sylvian fissure has been confirmed.
This technique makes transsylvian splitting safe and promising by increasing the visualization of adhesive brain structures.

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We investigated the clinical background, treatment and outcome of walk-in subarachnoid hemorrhage (SAH) patients by comparing those of ambulance-transferred patients.
Between April 2004 and December 2010, 85 SAH patients were hospitalized in our ward. Two of them were excluded from the study due to intra-hospital onset. There were 18 walk-in patients (mean age 63.8 years) and 65 ambulance-transferred patients (mean age 68.6 years). Only five of the walk-in patients visited hospitals on the onset day while most of all ambulance-transferred patients arrived immediately. The Hunt and Kosnik grade at admission (Grade 1: 6 of 18 vs. 4 of 65; Grade 2: 10/18 vs. 17/65; Grade 3: 2/18 vs. 10/65; 13 of Grade 4 and 21 Grade 5 found only in the ambulance group, p<0.01) and Fisher CT group (Group 1: 1/18 vs. 2/65; Group 2: 8/18 vs. 6/65; Group 3: 7/18 vs. 37/65; Group 3+4: 2/18 vs. 18/65, p<0.01) were better in the walk-in group than in the ambulance group. On the other hand, the presence of ruptured aneurysms (13/18 vs. 41/65) and surgical intervention rate (12/18 vs. 37/65) did not differ between groups. In the ambulance group, 18 patients could not undergo angiogram due to their poor clinical grade. Modified Rankin Scale at three months after onset was better in the walk-in group (Grade 0: 15/18 vs. 19/65; Grade 5: 0/18 vs. 30/65, p<0.01).
Though the walk-in group showed better neurological grade at admission, aneurysm rupture was the main cause of SAH in both groups, and surgical intervention rates were equally high. Therefore, adequate and prompt diagnoses and treatments were warranted.

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A 73-year-old female, who had been followed up for a right anterior cerebral artery aneurysm and a left middle cerebral artery aneurysm, presented with sudden onset of headache and loss of consciousness. CT showed subarachnoid hemorrhage (SAH) and subsequent three dimensional-CT angiography (CTA) revealed an enlargement of the anterior cerebral artery aneurysm, which was highly suspected to be the ruptured one. The aneurysmal neck was successfully clipped. After the 15th day, the follow-up CTA revealed a de novo aneurysm of the anterior communicating artery that had not been recognized either on the onset day or six months earlier. Because the de novo aneurysm was thought to be the cause of SAH, the aneurysmal neck clipping was then performed. The postoperative course was uneventful.
There are several reasons why the ruptured aneurysm was not identified during the first radiological study. In that case, intraluminal thrombosis could be the cause. We should keep in mind that rupture of de novo aneurysms can be associated with multiple unruptured aneurysms and should comprehensively identify ruptured aneurysms.

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We report two cases of pregnant females presenting with intracerebral hematoma caused by ruptured arteriovenous malformation (AVM).
A 21-year-old woman suddenly presented with severe headache, motor aphasia and right hemiparesis at 30 weeks of pregnancy because of a hematoma in the left frontal lobe. A cerebral angiogram showed AVM in the frontal lobe. We performed an emergency operation to remove the hematoma and AVM. The postoperative course was uneventful without neonatal complications. In the other case, a 32-year-old woman complained of headache and vomiting at 11 weeks of pregnancy. A CT scan indicated a right cerebellar hematoma. A cerebral angiogram revealed cerebellar AVM. An emergency surgical evacuation of the hematoma and AVM was performed. A complete cure was achieved after operation without complications.
Intracerebral hematoma in a pregnant woman can lead to the death of the mother and fetus. Appropriate diagnosis and treatment should be immediately undertaken to save maternal and neonatal life.

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