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Background Pial arterial feeders in an intracranial dural arteriovenous fistula (dAVF) are risk factors for both ischemic and hemorrhagic complications during endovascular embolization. Microsurgery in dAVF with pial arterial feeders has rarely been reported. Objective To assess our original experience with microsurgery for dAVF with pial arterial feeders by investigating surgical findings and outcomes. Methods In 40 patients with intracranial dAVF who underwent microsurgery, we found 8 patients who had pial arterial feeders. A retrospective review was conducted. Results The locations of the dAVFs were as follows: tentorium, 2 patients; Galenic system, 1; straight sinus, 1; torcula, 1; transverse sinus, 1; ethmoid, 1; and convexity, 1. Preoperative angiography revealed that the pial arterial feeders originated from the middle cerebral artery in 2 patients, the anterior cerebral artery in 1, the posterior cerebral artery in 2, and the posterior medial choroidal artery in 1. Of note, in 2 patients (6.7%), feeders from the superior cerebellar artery were determined to be angiographically occult during preoperative examination and were detected through careful intraoperative observation and arachnoid dissection. In 5 cases, the additional obliteration of the pial arterial feeders and/or more distal cortical venous drainers after the simple disconnection of proximal cortical drainers was necessary to cure the dAVF. Finally, all shunts were cured with only 1 minor complication. Conclusion Although microsurgical results were acceptable, the surgeon should be aware of the presence of pial arterial feeders even after the simple disconnection of cortical venous drainage. Angiographically occult feeders may also exist.

BackgroundOutcomes of endovascular treatment for acute ischemic stroke depend on the time interval from onset to reperfusion. Although the centralized ‘mothership’ method is considered preferable, the required transportation time increases the risk that a patient with a stroke may not receive intravenous or endovascular therapy. In contrast, ‘drive and retrieve’ describes a system wherein doctors from comprehensive stroke centers travel to primary stroke centers and provide endovascular treatment for acute ischemic stroke.ObjectiveTo describe the drive and retrieve system and verify the effects of this new collaboration on outcomes in patients with acute ischemic stroke among facilities.MethodsThis non-randomized, single-arm study retrospectively analyzed patients who met the inclusion criteria for endovascular treatment provided through a drive and retrieve system. Among the 122 patients treated by this system, we analyzed the time of onset to recanalization as the primary outcome. We also analyzed the efficacy of the drive and retrieve system using geographic information system analysis.ResultsThe median time from onset to recanalization was 229 min (IQR 170–307 min, 95% CI 201 to 252 min). The upper limit of the 95% CI for the time from onset to recanalization was shorter than the median times reported in two previous trials. Geographic information system analysis revealed an upward trend in the population coverage rate in each secondary medical area after the drive and retrieve method was introduced.ConclusionThe drive and retrieve method may be an effective form of cooperation between facilities located within 1 hour of a comprehensive stroke center.

Kissing aneurysms are defined as two adjacent aneurysms arising from identical or different arteries with separate origins and partially adherent walls. Mirror aneurysms are defined as intracranial aneurysms located in similar positions bilaterally on the parent arteries. Both kissing and mirror aneurysms at the anterior communicating artery(AcomA)are rare. We report a case of subarachnoid hemorrhage(SAH)due to ruptured kissing mirror aneurysms of the AcomA. An 80-year-old woman was admitted to our hospital with a sudden headache and vomiting. CT revealed diffuse SAH. Digital subtraction arteriography(DSA)revealed an aneurysm at the right A1-A2 junction of the AcomA. Hence, coil embolization was performed. On day 14 following embolization, rebleeding occurred. DSA revealed complete occlusion of the aneurysm at the right A1-A2 junction. However, left carotid angiography revealed an aneurysm at the left A1-A2 junction. We did not understand the anatomical construction of the aneurysms;therefore, we selected microsurgical treatment to clip the AcomA aneurysm using an interhemispheric approach. The left A1-A2 junctional aneurysm was anterior to the right A1-A2 junctional aneurysm, which was coil embolized. We detected the left A1-A2 junctional aneurysm as a ruptured aneurysm. The two aneurysms were adhered to each other. After dissection to expose the aneurysmal neck, the left A1-A2 junctional aneurysm was clipped. Kissing mirror aneurysms are difficult to diagnose before treatment. Knowledge and suspicion of the occurrence of kissing mirror aneurysms in the AcomA are important.

Although microsurgery is an established treatment modality for intracranial dural arteriovenous fistula (dAVF), data regarding the perioperative complication rate, cure rate, and long-term outcomes remain scarce. The aims of this study were to describe our original experience with microsurgery, including the surgical complications and pitfalls, and conduct a systematic review of the relevant literature. A multicenter cohort of patients with dAVF treated by microsurgery was retrospectively assessed. In addition, the PubMed database was searched for published studies involving microsurgery for dAVF, and the complication rate, cure rate, and long-term outcomes were estimated. The total number of patients in our multicenter series and published articles was 553 (593 surgeries). The overall rates of transient complications, permanent complications, death, and incomplete treatment were 11.4, 4.0, 1.2, and 6.5%, respectively. A favorable outcome was achieved for 90.1% patients, even though almost half of the patients presented with intracranial hemorrhage. Of note, the incidence of recurrence was only one per 8241 patient-months of postoperative follow-up. Surgeries for anterior cranial fossa dAVF were associated with a lower complication rate, whereas those for tentorial dAVF were associated with higher complication and incomplete treatment rates. The complication and incomplete treatment rates were lower with simple disconnection of cortical venous drainage than with radical occlusion/resection of dural shunts. Our findings suggest that the cure rate, complication rates, and outcomes of microsurgery for dAVF are acceptable; thus, it could be a feasible second-line treatment option for dAVF. However, surgeons should be aware of the specific adverse events of microsurgery.

The effect of HydroSoft coils on the prevention of recanalization and thrombosis after embolization is unclear. We herein report the results of the single-armed prospective Japanese HydroSoft Registry.Aneurysms with a diameter of10 mm that were treated with a ≥50% length of HydroSoft coils were registered. We evaluated the safety and recanalization rate and analyzed the factors related to their recanalization and thrombosis 1 year later.In total, 122 aneurysms were registered. Their mean maximum diameter and neck length were 6.4 and 3.9 mm, respectively. The mean length of the HydroSoft coils was 84.3%. No intracranial hemorrhage occurred, but 2 patients developed minor ischemic strokes. Angiographic examination immediately after the procedure showed complete obliteration, neck remnant (NR), and body filling (BF) in 20 (16.4%), 32 (26.2%), and 67 (54.9%) cases, respectively. One-year follow-up angiography showed complete obliteration, NR, and BF in 68 (55.7%), 15 (12.3%), and 15 (12.3%) cases, respectively, and 5 aneurysms (4.1%) were recanalized (4 and 1 with BF and NR as their initial angiographic result, respectively). Another 11 aneurysms still showed BF, although their thrombosis was promoted. No significant factors related to recanalization were identified. A high volume embolization ratio and small neck were significantly associated with thrombosis 1 year after embolization with HydroSoft coils.The safety and prevention of recanalization 1 year after the treatment appeared acceptable. The high volume embolization ratio associated with HydroSoft coils could induce progression of thrombosis for aneurysms characterized by NR and BF during the follow-up period.

Objective There are no established treatment strategies for aneurysms that recur after clipping. In this study, we present cases of patients who experienced recurrent aneurysms after clipping and subsequently underwent surgical intervention. Methods Between 2004 and 2015, we surgically treated 23 aneurysms that recurred at a previously clipped site. Patient characteristics and clinical history were retrospectively reviewed. Results Patients included 19 women and 4 men 45–81 years old. Aneurysms recurred 3–31 years (mean, 15.4 years) after the initial operation. For 18 cases, the first clinical presentation was a subarachnoid hemorrhage; aneurysms were incidentally diagnosed in 5 patients. Aneurysm locations were as follows: 9 on the internal carotid artery; 4 on the middle cerebral artery; 7 on the anterior communicating artery; 2 on the distal anterior cerebral artery; and 1 on the basilar artery. The reasons for retreatment included subarachnoid hemorrhage (n = 9) and aneurysm regrowth detected on follow-up examinations (n = 14). Endovascular treatment was performed in 10 cases, and direct surgery was performed in 13 cases (clipping in 8, clipping or trapping with bypass in 5). Various complex vascular reconstructions, including high-flow bypass and intracranial-intracranial in situ bypass, were performed for recurrent aneurysms. Conclusions In our experience, coil embolization is a safe and effective procedure for treating recurrent aneurysms. When cases are unsuitable for coil embolization, surgical treatment often requires neurosurgeons not only to overcome the general technical difficulty of reoperative clipping but also to perform challenging vascular reconstruction.

Systemic vascular diseases such as fibromuscular dysplasia, Ehlers-Danlos syndrome, Marfan syndrome, and Behçet's disease are known to cause spontaneous dissecting aneurysms of the cervical internal carotid artery. These diseases are generally associated with vascular fragility; therefore, invasive treatments are avoided in many cases of dissecting aneurysms, and a conservative approach is used for the primary disease. Surgical or intravascular treatment may be chosen when aneurysms are progressive or are associated with a high risk of hemorrhage; however, there is no consensus on which treatment is better. We report a case of a dissecting aneurysm of the cervical internal carotid artery in a patient with suspected Behçet's disease, which was treated using stent-assisted coil embolization. A man in his 40's, with suspected Behçet's disease, presented with an enlarged dissecting aneurysm of the right cervical internal carotid artery. The lesion was present for approximately 10 years. We performed stent-assisted coil embolization for the lesion. Post-surgery, no aneurysms were detected with carotid artery echography. Our case report suggests that stent-assisted coil embolization is a promising treatment for dissecting aneurysms of the cervical internal carotid artery. In addition, the procedure demonstrates the utility of carotid artery echograms for examining recanalization after stent-assisted coil embolization.

Background and Purpose: To discuss and summarize the strategies and complications of endovascular embolization for aneurysms of the posterior cerebral artery (PCA). Methods: Data of patients with PCA aneurysms treated by an endovascular procedure were analyzed retrospectively (n = 21). Twenty patients with aneurysms were treated by detachable coil embolization, and 1 patient was treated with n-butyl cyanoacrylate. Of the 21 aneurysm embolization cases, 9 were treated by parent artery occlusion (PAO), and 12 were treated by selective occlusion of the aneurysm (SOA). Results: All 12 aneurysms treated by SOA showed complete occlusion. Two aneurysms became recanalized 6 months after the first embolization and were then re-embolized; complete healing was observed on follow-up angiography. All patients showed acceptable outcomes without any procedural complications, except 1 patient who died 2 days after treatment. PAO resulted in 100% occlusion of all aneurysms. Cerebral infarction was noted in most patients (78%). However, the area of infarction was small. Permanent neurological deficit was observed in 2 patients (22%), but their condition was not critical. Conclusions: Aneurysm embolization with SOA is well indicated for saccular aneurysms with well-defined necks, whereas PAO carries a risk of ischemic complications. Although the PCA is rich in collateral circulation, ischemic complications were noted in most patients after PAO, and it was difficult to predict occurrence of these complications. However, the area of cerebral infarction tended to be small, and the neurological deficits observed were not critical.

Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant systemic disorder characterized by the enlargement of capillaries, recurrent nosebleeds, and multiple arteriovenous malformations (AVMs). Although cerebral AVMs are traditionally considered to be congenital lesions, some reports have described de novo AVMs, which suggests that the authors believed them to be dynamic conditions. In this article, the authors describe the case of a 5-year-old boy with HHT in whom a de novo cerebral AVM was detected after a negative MRI result at 5 months. To the authors’ knowledge, this is the first report of a de novo AVM in a patient with HHT. In patients with a family history of HHT, de novo AVMs are possible, even when no lesions are detected at the first screening. Therefore, regular screenings need to be performed, and the family should be informed that AVMs could still develop despite normal MRI results.

Purpose To investigate the appropriateness of the treatment policy of stereotactic irradiation using both hypofractionated stereotactic radiotherapy (HSRT) and stereotactic radiosurgery (SRS) for arteriovenous malformations (AVMs) located in an eloquent region or for large AVMs and using SRS alone for the other AVMs. Methods and materials Included in this study were 75 AVMs in 72 patients, with a mean follow-up of 52 months. Of the 75 AVMs, 33 were located in eloquent regions or were >2.5 cm in maximal diameter and were given 25–35 Gy (mean, 32.4 Gy) in four daily fractions at a single isocenter if the patient agreed to prolonged wearing of the stereotactic frame for 5 days. The other 42 AVMs were treated with SRS at a dose of 15–25 Gy (mean, 24.1 Gy) at the isocenter. The 75 AVMs were classified according to the Spetzler-Martin grading system; 21, 23, 28, 2, and 1 AVM were Grade I, II, III, IV, V, and VI, respectively. Results The overall actuarial rate of obliteration was 43% (95% confidence interval [CI], 30–56%) at 3 years, 72% (95% CI, 58–86%) at 5 years, and 78% (95% CI, 63–93%) at 6 years. The actuarial obliteration rate at 5 years was 79% for the 42 AVMs 2 cm. The 5- and 6-year actuarial obliteration rate was 61% (95% CI, 39–83%) and 71% (95% CI, 47–95%), respectively, after HSRT and 81% (95% CI, 66–96%) and 81% (95% CI, 66–96%), respectively, after SRS; the difference was not statistically significant. Radiation-induced necrosis was observed in 4 subjects in the SRS group and 1 subject in the HSRT group. Cyst formation occurred in 3 patients in the SRS group and no patient in the HSRT group. A permanent symptomatic complication was observed in 3 cases (4.2%), and 1 of the 3 was fatal. All 3 patients were in the SRS group. The annual intracranial hemorrhage rate was 5.5–5.6% for all patients. Conclusion Our treatment policy using SRS and HSRT was as effective as the policy involving SRS alone. The HSRT schedule was suggested to have a lower frequency of radiation necrosis and cyst formation than the high-dose SRS schedule. The benefit of HSRT compared with lower dose SRS has not yet been determined.

OBJECTIVE: Retrograde drainage into the cortical veins results in poor outcome in patients with an intracranial dural arteriovenous fistula. However, the pathophysiological features of dural arteriovenous fistulae remain obscure. This study aimed to clarify hemodynamic and metabolic conditions in these patients using positron emission tomography. METHODS: This study included eight patients with an intracranial dural arteriovenous fistula. All patients had cortical venous reflux, as demonstrated by angiography. Regional cerebral blood flow (rCBF), regional cerebral blood volume (rCBV), regional cerebral metabolic rate for oxygen, and regional oxygen extraction fraction (rOEF) were measured before and after surgical or endovascular treatment using positron emission tomography. RESULTS: Pretreatment position emission tomographic studies revealed that all patients had abnormal hemodynamic and metabolic parameters in the area that was drained by the involved cortical veins. A severe increase in rCBV was noted in seven of the eight patients. A significant decrease in rCBF also was observed in all eight patients. A negative correlation was observed between rCBF and rCBV. Three patients had an elevated rOEF. Oxygen metabolism was impaired in seven patient. All patients underwent successful treatment. Follow-up studies demonstrated significant improvements in rCBF, rCBV, and regional cerebral metabolic rate for oxygen. The improvement in regional cerebral metabolic rate for oxygen varied among the patients. Normalization of rOEF also was confirmed in three patients who had increased rOEF before the treatment. CONCLUSION: The present results suggest that hemodynamic and metabolic characteristics vary widely among patients with cortical venous reflux. it is essential to precisely evaluate hemodynamic and metabolic conditions to predict their outcomes and therapeutic effects.

Purpose. The purpose of this study was to evaluate the efficacy of rapid superselective high-dose cisplatin infusion with concomitant radiotherapy for previously untreated patients with advanced head and neck cancer. Methods. Forty-three patients for whom surgery was contraindicated or who rejected radical surgery were given superselective intra-arterial infusions of cisplatin (100–120 mg/m2/week) with simultaneous intravenous infusion of thiosulfate to neutralize cisplatin toxicity and conventional extra-beam radiotherapy (65 Gy/26 f/6.5 weeks). Results. Thirty-nine patients had stage IV disease, and the remaining four had stage III disease. During the median follow-up period of 21 months, the 3-year locoregional progression-free rates of all patients (n = 43) and patients with unresectable disease (n = 24) were 68.9% and 56.4%, respectively. In addition, the 3-year overall survival of all patients and patients with unresectable disease was 54.0% and 39.6%, respectively. Thirty-five patients (81.4%) experienced nonhematologic grade III to IV toxicity, including mucositis (n = 16), nausea/vomiting (n = 8), and neurologic signs (n = 2). No patient died as a result of treatment toxicity. There are 29 surviving patients without evidence of disease, all of whom are able to have oral intake without feeding-tube support. Conclusions. We confirmed the efficacy of superselective arterial infusion and concomitant radiotherapy, which can concentrate the attack of supradose cisplatin on locoregional disease. Even patients with unresectable disease can be cured. Further studies are needed to establish the indications, long-term outcome, and possible late side effects of this treatment. © 2004 Wiley Periodicals, Inc. Head Neck27: 65–71, 2005

BACKGROUND When considering the treatment strategies for dural arteriovenous fistulas (DAVFs), it is important to clarify the exact location of the fistula and venous drainage route from both DAVFs and normal brain tissue. DAVFs with leptomeningeal retrograde venous drainage carry a high risk of neurological deficits and require aggressive treatment. When AVFs involve the dural sinus, transvenous embolization via the transfemoral approach is usually the first choice of treatment. For DAVFs draining directly into the cortical veins without dural sinus involvement, transarterial embolization may be a curative treatment. However, when embolization is technically difficult or results in incomplete occlusion, surgical treatment is required. The purpose of the present study was to review our experience with surgical treatment of DAVFs. METHODS The present series included 17 patients; 9 had DAVFs involving the dural sinus with leptomeningeal retrograde venous drainage and 8 had DAVFs draining directly into the cortical veins. For DAVFs involving the sinus, embolization of the diseased sinus by direct surgical exposure was performed in 8 patients, and surgical excision in one. For DAVFs draining directly into the cortical veins, interruption of the draining veins close to DAVFs was undertaken in 7 and surgical excision in 1. RESULTS Complete obliteration of DAVFs was demonstrated in 16 patients. At final follow-up, 15 patients were asymptomatic and the other 2 showed clinical improvement. CONCLUSIONS For DAVFs involving the dural sinus, direct operative sinus packing is indicated. For DAVFs directly draining into the cortical veins, surgical interruption of the draining veins is indicated.

Object. In this report, the authors describe five consecutive patients with cervical perimedullary arteriovenous fistulas (AVFs) that were successfully treated using a corpectomy performed via an anterior approach. Methods. Five patients with cervical perimedullary AVF underwent corpectomy via an anterior approach. There were four women and one man who ranged in age from 34 to 62 years (median 55 years). Four patients presented with subarachnoid hemorrhage and one with intramedullary hemorrhage. All five AVFs were located on the anterior surface of the cervical spinal cord and fed by the anterior spinal artery. All patients underwent an anterior approach with 1.5- or two-level corpectomy, opening of the dura mater, and coagulation of the fistula. After dural closure, an iliac bone graft was inserted. Four patients were treated by surgery alone and one patient by embolization and surgery. Postoperative angiography revealed complete disappearance of the AVF in all patients. Neurological status improved in two cases and stabilized in the other three. There were no surgery-related complications. Conclusions. Safe and effective interruption of cervical AVFs can be accomplished by an anterior-approach corpectomy.

Background Carotid endarterectomy (CEA) and carotid stenting (CAS) are beneficial procedures for patients with high-grade cervical carotid stenosis. However, it is sometimes difficult to manage patients with bilateral carotid stenosis. To decide the treatment strategy, one of the most important questions is whether contralateral stenosis increases the risk of patients undergoing CEA. Methods This retrospective study included 201 patients with carotid stenosis who underwent a total of 219 consecutive procedures (CEA 189/CAS 30). We retrospectively analyzed outcomes in patients with carotid stenosis who were treated with either CEA or CAS and evaluated whether or not contralateral lesions increases the risk of patients undergoing CEA or CAS. Furthermore, we retrospectively verified our treatment strategy for bilateral carotid stenosis. Results The incidences of perioperative complications were 5.3% in the CEA patients and 6.7% in the CAS patients, respectively. There was no significant difference between these 2 groups. The existences of contralateral occlusion and/or contralateral stenosis were not associated with perioperative complications in both the groups. There were 32 patients with bilateral severe carotid stenosis (>50%). Of those, 13 patients underwent bilateral revascularizations; CEA followed by CEA in 8, CEA followed by CAS in 3, CAS followed by CEA + coronary artery bpass grafting in 1, and CAS followed by CAS in 1. Conclusions Our date showed that the existence of contralateral carotid lesion was not associated with perioperative complications, and most of our cases with bilateral carotid stenosis initially underwent CEA.

The number of patients with a ventricular assist device(VAD)will increase with the spread of heart transplantation in Japan. On the other hand, it is likely that VADs could cause cerebral embolism. However, there are few reports about endovascular therapy for intracranial embolic infarction from VAD. The authors report successful acute endovascular therapy for cerebral embolism. A 19-year-old woman with a VAD who received anti-coagulant treatment by warfarin sodium presented disturbance of consciousness and right hemiparesis. CT scan showed early CT sign in the left middle cerebral artery (MCA) area. 3D-CTA demonstrated occlusion of the left MCA and basilar artery (BA). We first performed endovascular recanalization in the left MCA, because IV tPA was ineligible. The left MCA was recanalized with TICI 2b perfusion and her symptoms were significantly improved. The treatment of the VAD patient reveals important issues. First, the femoral puncture requires ultrasound due to pulseless femoral artery. Second, the access route is an intact artery because of the anatomy of the VAD. Third, even if the patient has a hemorrhagic complication by intervention, the patient must be kept on anti-coagulant treatment because the VAD requires it. Careful consideration should be given to recanalization of occlusive vessels.

BACKGROUND Actinomycosis of the central nervous system is a rare disease that most frequently forms cerebral abscesses. In the present report, we describe an extremely rare case of spinal intrathecal actinomycosis. CASE PRESENTATION A 33-year-old man presented with high fever followed by back pain and paraparesis. Magnetic resonance imaging (MRI) with gadolinium-diethylene-triamine penta-acetic acid (Gd-DTPA) enhancement (Gd-MRI) displayed an irregularly enhanced mass lesion at the thoraco-lumbar junction that mimicked an intramedullary tumor with exophytic growth. Surgical exploration 7 months after the onset of the high fever revealed intrathecal granulation tissue with small abscess formation. Another surgical exploration was carried out 2 months after the first operation because the patient developed progressive paraparesis and showed an intrathecal ring-like enhancement that was detected with Gd-MRI. Actinomyces organisms were finally identified histologically in the surgical specimen. CONCLUSIONS The clinical course and serial changes of Gd-MRI findings are important considerations when this rare and infectious spinal lesion is suspected.

Background It is well known that carotid endarterectomy and extracranial-intracranial arterial bypass sometimes cause postoperative hyperperfusion, and vasoparalysis attributable to long-standing ischemia has been suggested as the cause. It is also well known that dural arteriovenous fistula (AVF) sometimes causes cerebral ischemia attributable to venous hypertension. However, there are few reports regarding the postoperative changes of regional cerebral blood flow (rCBF). Methods We report a case of dural AVF of the left transverse/sigmoid sinuses, occurring in a 64-year-old man. Intraoperative transvenous embolization combined with transarterial embolization was performed, and the rCBF was measured pre- and postoperatively using 99m Tc-hexamethyl-propylene amine oxime and single-photon emission computed tomography (SPECT). Results Preoperative SPECT disclosed a marked rCBF reduction in the left temporal, parietal, and occipital lobes. Complete obliteration of the AVF was attained after the intraoperative transvenous embolization, without any neurological deterioration. However, postoperative SPECT demonstrated temporary hyperperfusion in these regions. Conclusions Sudden resolution of venous ischemia can lead to postoperative hyperperfusion, and pre- and post-treatment rCBF studies are important to prevent complications related to hyperperfusion.

A 76-year-old man presented with subarachnoid hemorrhage. Selective angiography revealed a dural arteriovenous fistula (DAVF) at the right anterior clinoid process, draining into the superficial middle cerebral vein in a retrograde fashion. Two internal carotid artery aneurysms were also demonstrated at the origin of the posterior communicating artery and the anterior choroidal artery on the same side. The patient underwent craniotomy, and all lesions were treated simultaneously. Rupture of the anterior choroidal artery aneurysm was confirmed. DAVF draining directly into the superficial middle cerebral vein is extremely rare. The precise location of the shunt, the anatomical features, and venous drainage must be evaluated to consider treatment.

Isolated abducens nerve palsies associated with the rupture of intracranial aneurysms have rarely been reported. We report two cases of isolated bilateral abducens nerve palsies occurring after subarachnoid hemorrhage due to the rupture of an intracranial aneurysm. Case 1: A 49-year-old woman had bilateral abducens nerve palsies following subarachnoid hemorrhage due to the rupture of the left vertebral artery-posterior inferior cerebellar artery aneurysm. Case 2: A 55-year-old man had bilateral abducens nerve palsies following subarachnoid hemorrhage due to dissecting aneurysm of the right vertebral artery. Case 1 and 2 were treated with surgical clipping of the aneurysm and internal occlusion of the parent artery. In both cases, bilateral abducens nerve palsies achieved almost full recovery several months after treatment. It is speculated that the main causes of palsies are compression and stretching of the bilateral abducens nerves by a thick clot in the prepontine cistern. Although most of the abducens palsies may be reversible and have good prognosis, it is important that they are kept in mind as isolated symptoms of subarachnoid hemorrhage.

Purpose: Previous reports have suggested that endovascular parent artery occlusion is an effective and safe procedure for the treatment of vertebral artery dissection (VAD). However, the results of long-term outcomes are still unclear. This study reviewed the clinical and imaging outcomes of patients with VAD treated by endovascular internal trapping. Methods: A total of 73 patients were treated for VAD by endovascular internal trapping between March 1998 and March 2011. Patients were regularly followed up by magnetic resonance imaging, magnetic resonance angiography, and clinical examinations. Clinical outcomes were evaluated using the modified Rankin Scale. Results: Forty-five patients had ruptured VADs, and 28 had unruptured VADs. Clinical follow-up of at least 6 months data were obtained for 61 patients (83.6 %). The follow-up period ranged from 6 to 145 months (mean ± SD, 55.6 ± 8.9 months). Two patients with ruptured VADs had recurrence (2.74 %). Cranial nerve paresis (CNP) was observed in 6 patients (8.21 %), spinal cord infarction in 2 patients (2.74 %) and a perforating artery ischemia was diagnosed in 7 patients (9.59 %); all patients with CNP and 5 of the patients with partial Wallenberg syndrome experienced only temporary symptoms; 2 of the patients with partial Wallenberg syndrome had permanent neurological deficits. Despite their symptoms, most patients were in good general condition, as shown by their clinical scores. Conclusions: The results of this study have proven that endovascular internal trapping is a stable and durable treatment for closure of VADs. Recanalization is rather rare and occurred only in ruptured cases., both within 3 months after initial treatment without rupture. CNPs were observed in 8.21 %, perforating ischemia in 9.59 %, and spinal cord infarction in 2.74 %. The former two are temporary, while the last can be a factor that affect mRS. Patients rated their quality of life as good, as corroborated by their posttreatment clinical score. Endovascular internal trapping for VAD is a therapy with a satisfactory long-term outcome.

Ectopic pituitary adenomas are relatively rare tumors. We present a case of ectopic pituitary adenoma occurring in the sphenoid sinus. A 63-year-old woman was referred to our hospital complaining of headache. She had no endocrinological abnormalities. Magnetic resonance imaging showed a tumor in the sphenoid sinus, adjacent to the sellar floor and appearing as a low-signal on T1-weighted image and a high signal on T2-weighted image. No connection between the normal pituitary gland and tumor was observed. Using an endonasal-transsphenoidal approach assisted with neuro-endoscopy, we performed total removal of the tumor. No connection between the normal pituitary gland and the tumor was found. Histopathological analysis showed a pituitary adenoma. As demonstrated by our case report, differential diagnosis of a tumor occurring in the sphenoid sinus must include consideration of the existence of an ectopic pituitary adenoma.

The aim of our study is to report the outcome of our surgical procedure of conventional craniotomy for the evacuation of striatocapsular hemorrhage.During 2004 to 2008, 75 patients were admitted to our hospital because of striatocapsular hemorrhage. We assigned thirty one (41%) of the 75 patients to surgery. We employed prognosis-based outcome analysis.The average volume of hematoma in surgically treated cases was 95.2 ± 52.5 (30- 223.8) mL. Mortality rate was 16% at 6 months after the onset. In the total population, a favorable outcome was achieved in 65% assessed by using the Glasogow Outcome Scale, 37.3% by using a modified Rankin Scale and 38.7% by using the Barthel index, respectively.Our observational study indicated that the outcome through conventional craniotomy and evacuation of hematoma was superior to the outcome of typical previous studies. We also illustrated our surgical procedure to emphasize operative nuances.

The management of ruptured anterior communicating aneurysms remains controversial since the results of ISAT have been reported. The aim of our study is to report our decision-making process and outcome in 36 consecutive cases using endovascular coil embolization as a first choice of treatment.Thirty-six patients were studied. Since April, 2004, the treatment modality has been decided after discussion between the endovascular and cerebrovascular surgeons, taking into account the physiological status, treatment risk and morphology of the aneurysm.Twelve (33%) of 36 patients were allocated to coil embolization. Factors leading to the selection of clipping surgery were decided mostly by the morphology of the aneurysm, namely, tiny in 11 (47.8%), irregular shape in 6 (26.1%), broad neck in 3 (13.0%) and bleb located at the neck in 3 (13.0%). Half of the aneurysms projecting anteriorly were treated coil embolization.The allocation rate of endovascular treatment in ruptured anterior communicating aneurysms was 33%. Endovascular treatment was effective in at least half of the anterior the projecting aneurysms.

To describe techniques of exposure for middle cerebral artery (MCA) aneurysms located at the limen recess.A retrospective review was performed of 17 patients who underwent clipping surgery, during a 3-year period, to MCA aneurysms located at the limen recess. All clinical and imaging data were reviewed.Techniques required in the limen recess MCA aneurysms were: 1) Wide exposure of the sylvian fissure (from the distal part to the carotid cistern), 2) Secure the M1 proximal, 3) Temporary occlusion, 4) Perpendicular clip. Temporary occlusion was employed in 13 of 17 patients. No procedure related morbidity was observed.Difficulty lies in the circumstance that the aneurysm frequently has its orifice 270 degree, while the clip has to be applied perpendicular to the M2 axis in a narrow working space. Using temporary clip and extensive exposure may be the key to avoid brain damage in the surgery of MCA aneurysms located at the limen recess.

We report a case of bilateral agenesis of the internal carotid artery which was revealed by oclulomotor palsy and subarachnoid hemorrhage. Angiography showed a ruptured aneurysm of the left P1-2 junction and bilateral absence of the internal carotid artery. In surgery, it was necessary to use temporary clipping several times to adjust the aneurismal clipping. Complete clipping easily compromised the middle cerebral circulation. This case suggested that STA-MCA bypass should be considered in the surgery of agenesis of the internal carotid artery in which the preoperative hemodynamic status is usually normal.

Background Atheromatous aorta and carotid artery disease are known predictors for stroke after coronary artery bypass grafting (CABG). The clinical significance of intracranial cerebral artery disease is not known. This study was designed to determine whether a therapeutic strategy based on perioperative detection of intracranial and extracranial occlusive cerebrovascular disease and atheromatous aorta could reduce perioperative stroke. Methods We studied 485 patients who underwent isolated CABG. The control group was 247 patients who underwent standard-protocol CABG. The 238 subjects in the intervention group underwent preoperative magnetic resonance angiography of the head and neck and intraoperative epiaortic scanning. Cerebral hemodynamics were evaluated by single photon emission computed tomography and acetazolamide tests in patients with significant occlusive cerebrovascular disease. Surgical outcomes were compared. Results In the intervention group, magnetic resonance angiography detected significant intracranial or extracranial occlusive cerebrovascular disease, or both, in 40 patients. Prophylactic cerebrovascular interventions were performed in 7 patients who had disturbed cerebral hemodynamics. Aorta no-touch off-pump coronary artery bypass (OPCAB) was chosen intraoperatively in 37 patients with moderate to severe atheromatous aorta. The in-hospital stroke rate was 0.42% in the intervention group vs 2.8% in the control group (p = .068). A multivariate analysis revealed that the perioperative interventional protocol was the most powerful predictor of reduced risk of perioperative stroke (odds ratio, 0.023; 95% confidence interval, 0.001 to 0.469). Conclusions Prophylactic cerebrovascular interventions and the selective use of aorta no-touch OPCAB can significantly reduce the incidence of perioperative stroke. Careful vascular evaluation before and during CABG can improve surgical outcomes.

The aim of this study was to investigate cardiac performance and volume status after subarachnoid hemorrhage (SAH). Hemodynamic and volumetric parameters including cardiac index (CL), intrathoracic blood volume index (ITBVI), and extravascular lung water index (EVLWI) were evaluated by single indicator transpulmonary thermodilution (PiCCO) from days 1 to 4 in 32 patients with SAH treated surgically or endovascularly within 24 hours. Higher CL and lower ITBVI values were observed after SAH. The mean value of Cl was 5.2 l/min/m2 on day 1, which gradually decreased to 3.4 l/min/m2 on day 4. The mean ITBVI value was 730 ml/m2 on day 1, which recovered to the reference range until day 4 by fluid administration aiming for normovolemia. Higher CL and lower ITBVI values were present in patients with poor clinical grade (WFNS grade IV, V) as compared with mild to moderate grade (I -Ill) (p0.05). Relationship between CL and SI were well correlated (r = 0.77, p0.0001). The results indicate that SAH predisposes patients to hyperdynamic and hypovolemic states associated with sympathetic hyperactivity, especially in patients with poor clinical grade. Bedside monitoring with the PiCCO system may be a powerful tool for the management of patients after SAH.

In consideration of the treatment for multiple cerebral aneurysms occurring in association with subarachnoid hemorrhage, it is sometimes difficult to determine which therapeutic strategy should be used when it is difficult to detect the ruptured aneurysm by CT or angiography and difficult to clip all the aneurysms using one approach. This study was conducted to examine indications and problems of coil embolization in the acute stage in such a situation, based on our experience in 9 patients. The patients were aged between 29 to 91 years (mean 61.6 years), and the severity on admission was recorded according to the World Federation of Neurosurgical Societies (WFNS) Grade I in 6 patients, Grade II in 2 patients, and grade IV in 1 patient. The number of aneurysms was 2 in 5 patients, 3 in 3 patients, and 4 in 1 patient. Four patients underwent embolization for all the aneurysms simultaneously, 3 patients underwent embolization for a single aneurysm and then underwent clipping of other aneurysms, and 2 patients were considered to be eligible for surgery and underwent clipping, but since no rupture was detected, they underwent embolization for all the remaining aneurysms. Seven patients made satisfactory progress, but 1 patient developed an embolic complication. Another patient developed recurrent hemorrhage from the untreated aneurysm, so additional clipping was performed. Coil embolization is beneficial in that treatment is completed simultaneously, but has problems in that it cannot be determined whether or not the embolized aneurysm is the ruptured one, embolic complications may occur, and long-term prognosis is unknown.

Spinal dural AVF is the most common type of spinal AVMs. It affects especially old male with slowly progressive paraparesis in most cases. We have experienced a rare case of a middle aged male with spinal dural AVF who showed rapid deterioration in its course. The patient was treated with surgical interruption of AVF after transarterial embolization with NBCA. The patient improved well after the treatment, and intramedullary lesion on MRI disappeared after 4 years. The authors would like to stress the importance of early diagnosis and proper treatment for spinal dural AVFs.

Recently, there are increasing numbers of patients with occlusive carotid artery disease and coronary artery disease. Simultaneous or two-staged surgery for both lesions has been recommended for these patients to reduce the incidence of perioperative complications. However, therapeutic options for the patients with bilateral carotid artery stenosis and coronary artery disease have not been established. In this report, we describe two patients who successfully underwent carotid endarterectomy (CEA) and carotid artery stenting (CAS) on each carotid artery in parallel with coronary artery bypass grafts (CABG). A 49-year-old male with severe stenosis of the bilateral internal carotid artery (ICA) and heart failure underwent CAS on the right side. Next day, he successfully underwent CABG and CEA on the left side at the same time. A 62-year-old male with severe stenosis of the bilateral ICA and coronary artery disease underwent CAS on the right side and CEA on the left side with an interval of 7 days. Subsequently, CABG was performed uneventfully. No perioperative complication occurred in either patient. The results suggest that combination therapy of CAS and CEA would be a valuable option for patients with complex carotid/coronary artery diseases.

A 67-year-old male presented with a rare pseudoaneurysm caused by infection after carotid endarterectomy (CEA) performed for stenosis of the left internal carotid artery (ICA). Wound infection and recurrent bleeding from the operated ICA developed 1 month after surgery. Serial angiography showed that the post-CEA pseudoaneurysm gradually increased in size. The carotid balloon occlusion test revealed that the patient could not tolerate permanent ICA occlusion because of poorly developed collaterals. Direct surgical exposure of the aneurysm was impossible due to tight adhesion of the surrounding tissue, so common carotid to middle cerebral artery bypass using a radial artery graft was performed followed by ligation of the distal common carotid artery. Subsequently, retrograde blood flow from the ICA to the aneurysm was interrupted by embolization of the external carotid artery coil through the facial artery. Combined surgical and endovascular treatment is a therapeutic option for patients with post-CEA pseudoaneurysm, if either direct or endovascular surgery is unfeasible.

The authors report 9 patients who presented with loss of consciousness (syncope) due to occlusive carotid artery diseases. All patients were males, and their age ranged from 59 to 83 years. The attack was associated with dehydration or hypotension in 5 patients. MRI demonstrated fresh cerebral infarction in the watershed zone. Cerebral angiography revealed occlusion of the unilateral internal carotid artery (ICA) in 7 patients, severe stenosis of the bilateral ICA in one, and occlusion of the unilateral ICA and severe stenosis of the contralateral ICA in one. Single photon emission tomography (SPECT) or positron emission tomography (PET) suggested reduced cerebral perfusion reserve because of inappropriate development of collateral circulation in 4 out of 9 patients. These 4 patients underwent superficial temporal artery to middle cerebral artery anastomosis and/or carotid endarterectomy. Other 5 patients were medically treated. No further episode of syncope occurred in all 9 patients during follow-up periods. The results suggest that occlusive carotid artery diseases should be taken in considerations as a cause of syncope attack.

Combined therapy of direct sinus packing and surgical excision for intracranial dural arteriovenous fistula (dAVF) has not been reported in the literature. A 53-year-old male was admitted to our hospital due to sudden onset of seizure and consciousness disturbance. Plain CT scan showed subcortical hematoma in the right temporal lobe. Cerebral angiography revealed dAVF involved in the right transverse and sigmoid sinuses. The lesion was associated with retrograde venous drainage into the right cerebellum, temporal, and occipital lobes. Positron emission tomography (PET) showed typical findings of venous hypertension in the involved areas. MRI also demonstrated a high intensity lesion in the medulla oblongata, suggesting critical venous congestion. First, we aimed to pack the involved sinus through a minor craniotomy, but cannulation into the sinus was impossible probably because of a marked fibrosis in the involved sinus. Then, we completely exposed the involved sinus through craniotomy. Through a microcatheter inserted into the sinus, the lower part of the sigmoid sinus was directly packed, and the remaining lesion was excised. Postoperative course was uneventful. Disappearance of dAVF resolved the findings on PET and MRI. Combined therapy would be a safe, non-invasive, and useful option for patients with a complex intracranial dAVF.

The frequency of surgical treatment for intracranial aneurysms that have been incompletely treated by endovascular coiling will increase in time. The authors describe their experience in the following 3 patients. There was one non-ruptured aneurysm and two ruptured ones. The intervals between coiling and surgery were 1, 5, and 10 months. Surgery was indicated because of partial treatment and/or growth of residual neck. Observation during surgery revealed that coils were exposed to the subarachnoid space at the tip of the aneurysm in the cases of ruptured aneurysms. When the residual neck was large enough for the size of the clip blades, there was no need to remove the coils. The coils in the neck were able to be removed when the interval between coiling and surgery was very short, but could not be removed when the interval was prolonged. Intraoperative angiography and reconstructive bypass surgery may be essential in these complex cases. As pointed out previously, the operative approach should be determined by the need for coil removal and the duration since coiling.

The authors report the case of a rare manifestation by vertebral artery dissection. A 15-year-old boy who presented with left shoulder weakness and numbness of the left arm was admitted to our hospital. Neurological examination on admission revealed muscle weakness of the left deltoid muscle and sensory disturbance of the left C5 area. MRI/MRA and 3D-CT angiography demonstrated an aneurysm-like dilatation of the left vertebral artery mainly at the C4/5 level. Partial thrombosis was noted in the dilated artery. The left vertebral angiogram showed that the second and third portions of the left vertebral artery had a dilated pseudo-lumen due to arterial dissection. The pseudo-lumen of the dissected vertebral artery was largest in diameter at the C4/5 level. The patient successfully underwent proximal occlusion of the dissected vertebral artery using detachable balloon and Guglielmi detachable coils. Proximal vertebral artery occlusion using an intravascular technique was regarded as a non-invasive and effective option for patients with a cervical radiculopathy due to cervical vertebral artery dissection.

There is increasing evidence that stenting is a useful strategy for internal carotid artery (ICA) stenosis in patients unfit for drastic surgery. However, it should be remembered that perioperative complications including seizure or intracerebral hemorrhage due to hyperperfusion are not so rare. The authors describe a case with severe ICA stenosis, who successfully underwent stenting as a result of intensive medical care for postoperative hyperperfusion. A 77-year-old man with a recent history of angina pectoris and transient ischemic attack was referred to our hospital. Cerebral angiography showed subtotal occlusion of the left ICA. SPECT/PET studies revealed a disturbed reactivity to acetazolamide and an increase in regional oxygen extraction fraction in the left hemisphere, suggesting a marked reduction in cerebral perfusion pressure. He successfully underwent carotid stenting. Intraoperative near-infrared monitoring showed an increase in the concentration of total and oxidized hemoglobin in the left frontal area after stenting. A SPECT study just after stenting also demonstrated hyperperfusion in the left middle cerebral artery territory. His blood pressure was carefully controlled to avoid "hyperperfusion syndrome" including headache, seizure and intracerebral hemorrhage. Follow-up SPECT/PET studies showed a normalization of hemodynamic and metabolic parameters. SPECT/PET studies are quite valuable to predict and prevent hyperperfusion syndrome after carotid stenting, and result in good clinical outcome.

A three-dimensional (3D) reconstruction method of arteriovenous malformation (AVM) nidus from digital subtraction angiography (DSA) in combination with CT and/or MRI was developed, and its usefulness was evaluated in this study.The contour of the AVM nidus was delineated on two orthogonal projected DSA images. First, the volume and center of the AVM nidus were calculated in a classic DSA plan using three maximal lengths of the nidus in three perpendicular directions, assuming that the nidus had a prolate ellipsoid shape. Second, in the 3D-DSA plan, the contours of the AVM nidus on the two orthogonal projected DSA images were segmented to be compatible with the slice thickness of the CT image. Assuming that each segment of the nidus has an ellipsoid pillar shape, the volume and center of each segment were calculated. The volume and 3D shape of the nidus were calculated by 3D reconstruction in the 3D-DSA plan. Third, in the CT-DSA plan, the contour based on the segmented DSA was superimposed on the corresponding transaxial CT image slice by slice. The cylindrical shape of the nidus in the transaxial image was modified using the enhanced CT images in the CT-DSA plan. These three planning methods were compared using dose-volume statistics from real patients' data. Eighteen patients with intracranial AVMs in different brain locations who had been treated by radiosurgery were the subjects of this study. To examine the visibility (validity) of the nidus on the CT image, the "nidus" was delineated on an enhanced CT image without DSA superposition in the CT plan and compared with the CT-DSA plan.The variance in the distance between coordinates determined by the CT plan and those determined by the classic DSA plan was significantly larger than the variance in the CT-DSA plan (p0.0001 for lateral, AP, and craniocaudal directions). The difference in the variance was not reduced by the addition of MRI (p0.0001 for each direction). The mean volume +/- SD of the nidus calculated was 5.9 +/- 8.0 cm(3) in the classic DSA plan, 4.0 +/- 5.6 cm(3) in the 3D-DSA plan, and 3.6 +/- 5.2 cm(3) in the CT-DSA plan. The 3D-DSA plan significantly reduced the mean nidus volume 31.8% +/- 12.7% from the classic DSA plan (p = 0.0054). The CT-DSA plan further significantly reduced the volume 9.8% +/- 8.8% from the 3D-DSA plan (p = 0.0021). The mean overlapping volume of the nidus between the CT plan and CT-DSA plan was 2.6 +/- 4.3 cm(3) (range 0.17-18.9), corresponding to 63.7% +/- 19.2% (range 11.4-85.3%) of the volume in the CT-DSA plan.The superposition of the segmented DSA information on CT was shown to be an important tool to determine the precise shape of the nidus and is suggested to be useful to reduce partial occlusion of the AVM or radiation complications in radiosurgery.

BACKGROUND AND PURPOSE: Our purpose was to evaluate the visualization of the artery of Adamkiewicz (AKA) and the anterior spinal artery (ASA) by using multi-detector row CT. Preoperative detection of the AKA and ASA is important for prevention of ischemic complications of thoracoabdominal aortic surgery. METHODS: Data from contrast-enhanced CT of the abdomen of 19 consecutive patients with known or suspected liver disease were evaluated. The scanning range was set from the level of the diaphragm to the lower edge of the liver. After bolus injection of contrast material (100 mL of iohexol, 350 mgI/mL, 5 mL/s), arterial phase scans were obtained by using a four-channel multi-detector row CT scanner. The scanning parameters included a detector row configuration of 4 × 2 mm, a pitch of 5:1, a gantry rotation speed of 0.5 s, 120 kVp, and 150 mAs. Arterial phase coronal multiplanar reconstruction scans obtained parallel to the spinal cord were evaluated by two neuroradiologists. The detectability of ASA and AKA was analyzed. RESULTS: The AKA was visualized on the scans of 13 of 19 patients (68%). The segmental level of AKA origin ranged from T10 to L2. The AKA originated from the left side in nine patients (69%) and the right side in four patients (31%). The ASA was visualized on the scans of all patients (100%). For 16 of the 19 patients, the ASA was detected in its full length from the cranial edge of the scan range. However, the ascending branch of the ASA distal to the junction of the AKA was not detected for the remaining three patients. CONCLUSION: The AKA and ASA can be visualized by using multi-detector row CT with the use of IV administered contrast material. Multi-detector row CT could be a useful tool in the evaluation of spinal vascular structures.

We report three cases of radiation-induced carotid arterial stenosis that underwent successful angioplasty with stenting. The patients had received radiation therapy for tongue or laryngeal cancers and developed minor completed strokes 6 to 14 years after irradiation. All patients had multiple and bilateral stenosis, measuring more than 50%, of the carotid arteries. The stenosis was located in the internal, external, and common carotid arteries. We performed percutaneous transluminal angioplasty with stenting. All interventions were successful and carotid stenosis decreased to less than 28%. No permanent complications occurred. During follow-up periods of up to 26 months, all of these cases were free from ischemic symptoms. Neither carotid angiography nor ultrasound sonography showed evidence of restenosis. The present results suggest the usefulness of angioplasty with stenting for radiation-induced carotid arterial stenosis.

An 81-year-old male presented with right oculomotor nerve paresis and left hemiparesis caused by a mass effect of a large superior cerebellar artery aneurysm. Endovascular treatment was performed using Guglielmi detachable coils. The patient subsequently suffered aggravation of the mass effect 3 weeks after the embolization. Bilateral vertebral artery occlusion was performed, which decreased the cerebral edema surrounding the aneurysm, but his neurological symptoms did not improve. Parent artery occlusion is recommended as the first choice of treatment for an unclippable large or giant aneurysm causing a mass effect on the brainstem.

Functional prognosis after treatment for spinal dural arteriovenous fistulas (SDAVFs) was retrospectively analyzed in 13 consecutive patients aged 38 to 73 years (mean 57 years) treated during the last 5 years. The duration of symptoms before diagnosis ranged from 3 to 72 months (mean 23 months). Neurological symptoms were examined before and 6 months after the treatment. Seven patients underwent embolization as the initial treatment. In four of six patients, N-butyl 2-cyanoacrylate (NBCA) embolization achieved complete obliteration of SDAVF. The other two patients with incomplete embolization and one embolized with polyvinyl alcohol particles underwent subsequent surgical treatment. Six patients were treated by direct surgery. Complete disappearance of SDAVF was confirmed in all nine patients treated surgically. Improvement of gait and micturition disturbance after the treatment was noted in six of 10 and three of six patients, respectively. Long duration of symptoms and high grade of neurological symptoms were associated with a poor functional outcome. NBCA embolization and surgery are curative treatments for SDAVF, but the functional prognosis is not always satisfactory. Embolization is the first choice of treatment for SDAVF because it is less invasive and relatively safe. However, when complete obliteration is not achieved, prompt surgery is recommended because a long duration of symptoms will result in a poor functional prognosis.

BACKGROUND Aneurysms of the extracranial vertebral artery (VA) and vertebral arteriovenous fistulas (VAVFs) are relatively rare diseases. The most frequent cause of both diseases is trauma. Atraumatic lesions are less common. Presented here is a case of atraumatic AVF of the extracranial VA that developed in the same location as a previous ruptured aneurysm of the ipsilateral VA that was originally treated by proximal occlusion 11 years earlier. METHODS A 40-year-old woman presented with a massive hematoma in the upper posterior neck region caused by the rupture of an extracranial VA aneurysm. Proximal occlusion of the VA was performed by use of a detachable balloon. She enjoyed good health for 11 years, then she noticed a pulsatile bruit. Angiograms revealed an AVF between the left VA that was fed by collateral circulation and the paravertebral venous plexus. Incidentally found were soft tissue masses in the left retroauricular and the right suboccipital regions. Also, skull X-ray films showed multiple bony defects. Biopsy of the subcutaneous mass was performed in the hope of obtaining clues as to which pathological processes had weakened the artery. RESULTS As direct transarterial access to the fistula was out of the question, the fistulous compartment of the paravertebral venous plexus was tightly packed with multiple platinum coils effected by the transfemoral approach. A histological examination of the specimen revealed features of a neurofibroma, and a diagnosis of neurofibromatosis Type 1 was established. CONCLUSIONS In this case, transvenous embolization of the VAVF was successfully performed. The fragility of the arterial wall, related to neurofibromatosis Type 1, was considered to contribute to the development of the aneurysm and AVF.

Four patients with multiple intracranial dural arteriovenous fistulas (DAVFs) at separate sites were treated by endovascular techniques (transarterial and/or transvenous embolization), surgery (excision or isolation), radiotherapy, or combinations, according to the pathophysiological condition. All lesions in two patients were obliterated completely without neurological deficit. There were residual fistulas after the treatment in two patients, but these were low-grade lesions without retrograde cortical venous drainage, and marked clinical improvement was obtained. Planning of treatment strategies for multiple DAVFs requires careful analysis of the venous drainage from the affected sinuses and cerebral hemodynamics.

This 63-year-old man presented with a right temporoparietal cortical infarction. A dural arteriovenous fistula involving the right transverse sinus was diagnosed on cerebral angiography. Transvenous embolization using detachable coils was performed; however, postembolization angiograms demonstrated retrograde filling of a cortical draining vein that was not seen on initial angiography. The patient subsequently developed a cerebral abscess in the region of the previous cortical infarction 2 months after the embolization. The abscess was successfully treated with drainage and antibiotic therapy. The authors report this case to illustrate an unusual complication associated with this procedure and the possible contribution of the cortical draining vein in the pathogenesis of the cerebral abscess.

✓ The authors describe the case of a 69-year-old man with an intracerebral hemorrhage due to rupture of a nontraumatic aneurysm of the middle meningeal artery (MMA). The ipsilateral posterior cerebral artery (PCA) was occluded, and dural anastomoses developed as the main collateral pathway between the MMA and the cortical branch of the PCA, on which the aneurysm was located. It is considered that increased hemodynamic stress to the collateral pathway contributed to the formation of the aneurysm.

We investigated the use of hypofractionated stereotactic radiotherapy (HFSR) to reduce adverse radiation effects in comparison to single-fraction stereotactic radiosurgery (SRS) for intracranial arteriovenous malformations (AVMs).This study includes 53 intracranial AVMs treated between 1991-1998. HFSR was selected for 26 AVMs with a maximum diameteror 2.5 cm or at eloquent area. Twenty-seven patients were treated with SRS (18 AVMs2.5 cm at non-eloquent area, nine patients who were unfit for prolonged ring-wearing). The most frequent minimum dose (Dmin) was 20 Gy for SRS and 28 Gy for HFSR in four fractions. The mean follow-up duration was 34.6 months for SRS and 35.4 months for HFSR.As a whole, the 3 and 5-year actuarial obliteration rates were 64 and 92%. Age20 years old (P=0.02) and a maximum diameter2 cm were favorable factors (P=0.05). A difference in the distribution of patients was observed in size (or =2.5 cm or not) (P0.001) and location (eloquent or not) (P0.001) between SRS and HFSR due to the treatment selection. However, no significant differences were observed in the actuarial rates of obliteration and transient increased signals with T2-weighted MR images between SRS and HFSR. Radiation necrosis occurred in two patients treated with SRS and in none with HFSR. Intracranial hemorrhage after treatment happened in two treated with SRS and three with HFSR.HFSR appears to be at least as effective as SRS in achieving complete obliteration of intracranial AVM, although its definitive role remains to be investigated.

Object Radiosurgical treatment of spinal arteriovenous malformations (AVMs) is becoming a practical therapeutic option as methodology improves, but no comparative study has yet been published on focal fractionated radiotherapy. The authors report their experience with conventional and hypofractionated radiotherapy for spinal AVM. Methods Candidates for this study were patients who experienced symptoms due to an intramedullary AVM but were ineligible for embolization or surgery. Of 21 patients with spinal AVMs, 10 cases in a 10-year period met this criterion. Angiography and contrast-enhanced computerized tomography scanning were used for treatment planning in all cases. Fractionated radiotherapy was performed using a linear accelerator, extracranial immobilization system, and frequent orthogonal linacographic verification. The starting radiation dose was 32 Gy in two, 36 Gy in three, and 40 Gy in two patients, in a regimen involving 1.8 to 2—Gy daily fractions; this was recently changed to a hypofractionation schedule of 30 Gy (in eight sessions) in one and 20 Gy (in four sessions) in two patients. Results The follow-up period ranged from 26 to 124 months (median of 49 months). There were no hemorrhages nor any adverse reactions attributable to irradiation. Of the seven patients who consented to undergo follow-up angiography, the nidus size decreased in five, but complete obliteration did not occur in any patient. Conclusions Because no patient experienced adverse effects, the maximum tolerable radiation dose for the spinal cord associated with an AVM could not be identified, although it presumably is higher than those administered. The lack of rebleeding in patients in whom complete angiographic occlusion was absent suggests that the natural history of spinal AVMs may be less aggressive than previously reported.