Search

A 74-year-old Japanese woman with a 1-year history of right preauricular pain and a 2-month history of bleeding from the right ear was admitted to our department. Tumor was observed in the anterior wall in the right external auditory canal. Bony swelling of the right preauricular area was palpated. Computed tomography revealed an ill-defined, osteogenic tumor around the mandibular condyle with a destructive bony lesion involving the temporal bone. Magnetic resonance imaging revealed a 2.0 × 1.5 × 1.3-cm solid tumor around the mandibular condyle, exhibiting a low-intensity signal on T1-weighted imaging and an isointense central area surrounded by low-signal intensity on T2-weighted imaging. Histological examination of biopsy specimens revealed diffuse-type tenosynovial giant cell tumor (D-TGCT). After the feeding arteries for the tumor were embolized, the patient underwent surgery with combined temporal craniotomy and mandibular condylectomy. The soft and cystic tumor with calcification located in the extradural space was totally resected along with the mandibular condyle. No facial paralysis or recurrence was evident as of 6 months postoperatively. To date, only 23 cases of D-TGCT arising in the temporomandibular joint (TMJ) with ear involvement have been reported since 2011. We report successful resection of a rare case of D-TGCT arising in the TMJ.

Purpose Right-sided aortic arch is a rare vessel anomaly with an incidence of 0.1% worldwide. Supra-aortic branches form a mirror image of the left-sided aortic arch or an aberrant left subclavian artery associated with Kommerell diverticulum. Most patients are diagnosed by a difference in blood pressure in each upper extremity or by the presence of left subclavian steal syndrome in their younger age. The diagnosis of onset of ischemic stroke in middle age is rare. Methods We present the case of a female patient who presented with an ischemic stroke in the left posterior circulation area. She had no history of congenital heart malformation. We performed head magnetic resonance imaging, cerebral angiography, and enhanced computed tomography of the aortic arch and major branches. Results The patient had a right-sided aortic arch and an aberrant left subclavian artery. The left subclavian artery was occluded at the proximal portion with a fibrous string. Collateral flow in the anterior cervical subcutaneous area supported left limb perfusion. Conclusion An atheromatous change reduced shunt flow via collateral networks at the anterior cervical region. Congenital subclavian steal supported the ischemic stroke.

Background and importance Traditionally, it has been believed that the plexal segment of the anterior choroidal artery (AChoA) can be sacrificed safely. Here, we present a case of choroid plexus arteriovenous malformation (AVM) in which the capsulothalamic artery originated from distal plexal segment of the AChoA. Clinical presentation A 45-year-old man was diagnosed with arteriovenous malformation involving the left inferior horn in screening MRI. Preceding stereotactic radiosurgery, transarterial target embolization was performed. In this procedure, 20% n-butyl-2-cyanoacrylate (NBCA) was successfully injected from the lateral plexal branch of the AChoA. After embolization, right homonymous hemianopsia developed due to cerebral infarction on the left optic radiation. This infarction was considered to be within the territory of the capsulothalamic artery. Conclusion This anomalous capsulothalamic artery might be formed by hemodynamic compromise of the brain surrounding AVM in early gestation. We must be aware of this unusual anatomical variation to avoid ischemic complication in embolization of the AChoA.

Mechanical thrombectomy using a stent retriever for acute large vessel occlusion is indispensable in stroke treatment, however, vasospasm may occur. The objective of this retrospective study was to investigate which cases are more likely to experience vasospasm after thrombectomy with stent retrievers.We included 29 patients diagnosed with acute cardiogenic cerebral embolism who were treated with stent retrievers at our facility from December 2014 to December 2017. Atherothrombotic brain infarction cases were excluded because it was difficult to evaluate for vasospasms. Vasospasm was defined as reversible arterial narrowing of80% of the normal vessel diameter after usage of the stent retriever. The age, sex, type of stent retriever, occlusion site, number of procedures, thrombolysis in cerebral infarction (TICI) grade, degree of vasospasm, intracranial hemorrhage by the procedure, and neurological outcomes were analyzed.Among the 29 cases, 12 (41.4%) resulted in vasospasm; nine cases were mild (20-50% stenosis) and 3 cases were severe (≥50% stenosis). Vasospasm frequently occurred in the distal part of the anterior circulation when compared to the proximal part. In addition, the frequency of vasospasm increased as the number of procedures increased. Pooled analysis showed significant difference in the intravenous tissue-type plasminogen activator group (P = 0.029). There was no significant difference in the other groups.Stent retrievers appear to cause vasospasm more than expected when including mild cases. Vasospasm tends to occur especially in cases with IV-tPA; prognosis is generally good, and it rarely requires any treatment.

Purpose Although several strategies against recurrent chronic subdural hematoma (CSDH) have been proposed, no consensus has been established. Recently, middle meningeal artery (MMA) embolization has been proposed as radical treatment for recurrent CSDH. We wanted to estimate the usefulness of MMA embolization for recurrent CSDH. Methods From February 2012 to June 2013, 110 patients with CSDH underwent single burr-hole surgery with irrigation and drainage. Among these patients, 13 showed recurrent hematoma formation and were retreated surgically. Furthermore, repeated recurrence of CSDH was observed in six patients. Five of these six patients underwent middle meningeal artery (MMA) embolization with polyvinyl alcohol particles. All five patients with interventional treatment were observed for four to 60 weeks. Results No more recurrence of CSDH was observed in any of the patients. During the follow-up period, no patients suffered from any side effects or complications from the interventional treatment. Conclusion MMA embolization with careful attention paid to the procedure might be a treatment of choice for recurrent CSDH.

Introduction Although cavernous sinus (CS) dural arteriovenous fistulas (d-AVFs) are usually treated with transvenous embolization (TVE) via the inferior petrosal sinus (IPS), IPSs are sometimes thrombosed and angiographically invisible. In such cases, the first obstacle to TVE is detecting the entry to the IPS. We report a new technique for TVE via IPS using intravascular ultrasonography (IVUS). Methods Three consecutive cases of CS d-AVF with ipsilateral or bilateral IPS occlusion were involved in this study. On TVE, the orifice of the IPS was investigated with IVUS placed in the jugular vein or jugular bulb. Results This technique has been successfully adapted in all three cases. In two of these cases, IPS was well visualized with the help of IVUS, and TVE was successfully performed. Conclusion To our knowledge, this is the first report to mention the usefulness of IVUS for detecting angiographically occult IPS.

Background and Purpose Among adults with posterior fossa tumors, an intraaxial location of the tumor is less common than an extraaxial location. Moreover, the differential diagnosis of a single cerebellar tumor in adults is sometimes difficult by conventional magnetic resonance imaging. We aimed to report the findings of positron emission tomography (PET) using 18F-fluorodeoxyglucose (FDG) and methionine in adult patients with intraaxial and solitary metastatic brain tumors. Materials and Methods FDG-PET was performed on 12 patients with posterior fossa tumors: 4 had solid hemangioblastoma (HB), 3 had primary central nervous system lymphomas, 1 had a glioblastoma, and 4 had single metastatic brain tumors (METs). Methionine-PET was performed on 9 patients except for 1 patient with a MET. The maximum standardized uptake value (SUVmax) of the tumor was measured and compared with pathologic findings. Results The SUVmax of FDG in HB was lower compared with that of other tumors (P = 0.001). On the other hand, the SUVmax of methionine in the HB cases was almost the same as that in other tumors (P = 0.07). Conclusion FDG-PET was helpful in differentiating HBs from adult cerebellar tumors.

Recently, transarterial embolization (TAE) with liquid embolic materials has been recognized as one of the curative therapeutic options for non-sinus type dural arteriovenous fistula (d-AVF). To prevent glue fragmentation and incomplete obliteration, flow reduction of transosseous high-flow feeders is one of the key points of this therapy. However, flow reduction of transosseous feeders is sometimes difficult with previously reported techniques such as particle embolization, manual compression, or proximal balloon occlusion. This report introduces a new technique to reduce the flow of transosseous feeders using epinephrine-containing lidocaine, and describes a case of intracranial d-AVF successfully treated with this technique. The usefulness and efficacy of the technique are discussed.

Carotid artery stenting (CAS) is an effective and less invasive alternative to carotid endarterectomy for internal carotid artery (ICA) stenosis, but the guiding catheter is often technically difficult to introduce into the common carotid artery (CCA) in patients with concomitant atherosclerotic disease in the peripheral vessels or aorta. A new pull-through technique between the superficial temporal artery (STA) and the brachial artery was used to deliver the guiding catheter into the CCA safely and steadily. An 83-year-old male presented with repeated transient left hemiparesis caused by severe stenosis of the origin of the right ICA. He also had severe systemic atherosclerotic disease with occlusion of the bilateral femoral arteries. The innominate artery branched at an acute angle from the aorta. Therefore, catheterization of the right CCA seemed to be impossible using a conventional approach. The guidewire introduced from the right STA was lassoed by a loop snare wire and pulled out of the left brachial artery, forming the pull-through system. The guiding catheter could be introduced into the CCA from the left brachial artery over this guidewire. Subsequently, successful stent placement was performed under the distal protection. This new technique may facilitate safe and stable CAS even in patients with a severely tortuous access route due to concomitant atherosclerotic disease.

A 61-year-old woman was admitted for head injury after a traffic accident. Two months later, she developed abducens nerve palsy, chemosis, and pulsatile tinnitus. Right internal carotid angiography demonstrated a high flow direct carotid-cavernous fistula (CCF) at the C(5) portion with reflux into the superficial and deep sylvian veins, superior ophthalmic vein, superior petrosal sinus, and inferior petrosal sinus. Intravascular ultrasonography (IVUS) revealed a large fistula at the C(5) portion of the internal carotid artery (ICA). Coil embolization via transarterial and transvenous approaches under IVUS monitoring was performed. During the procedure, IVUS accurately detected protrusion of a coil into the parent ICA, and the parent artery could be preserved. IVUS monitoring is useful for embolization of direct CCF with coils.

We report the case of a fusiform middle cerebral artery aneurysm at the M1 segment, which was successfully treated with proximal occlusion after a bypass surgery. A 48-year-old-male was admitted with a chief complaint of repeated left hemiparesis. Cerebral angiography showed a fusiform aneurysm at the M1 segment on the right side, corresponding to the ischemic symptom. We performed the occlusion of M1 at its most proximal segment after the high flow bypass from external carotid artery to M2 with a radial artery graft. The post-operative course was uneventful, and the patient was discharged 10 days after operation. Follow-up imaging studies showed the prominent thrombus formation inside the aneurysm keeping the blood flow from the aneurysmal wall to the M1 perforators intact. This surgical result supports the hypothesis that the spontaneous fusiform MCA aneurysm might be caused by dissection and the reversing of blood flow inside the dissected artery might make the dissection subside.

Object The authors evaluated their surgical experience over 20 years with 14 treated falcotentorial meningiomas. Methods In the past 20 years, 14 patients with falcotentorial junction meningiomas were surgically treated. There were seven men and seven women, whose ages ranged from 34 to 79 years. On the basis of neuroimaging studies, the authors analyzed the influence of the anatomical relationship of the tumor to the vein of Galen, patency of the vein of Galen, tumor size, and the signal intensities on the magnetic resonance images to determine possible difficulties that might be encountered during surgery and to prognosticate the outcome of surgery. Depending on the relationship with the vein of Galen, tumors were labeled as either a superior or an inferior type. All tumors were resected via an occipital transtentorial approach. The surgical outcome in eight patients was excellent; in the remaining six patients, it was fair. Of the prognostic factors, tumor location especially seemed to be the most important (p < 0.01, Fisher exact test). The outcome associated with the inferior type of tumor was significantly less optimal probably due to the relationship to the deep veins and the brainstem. In this series, the occlusion of deep veins did not significantly influence outcome. Conclusions Classification of the tumor location by preoperative neuroimaging studies can be helpful in estimating the surgical difficulty that might be encountered in treating the falcotentorial junction meningioma.

We report two rare cases of progressive congestive myelopathy caused by dural arteriovenous fistulae (DAVF) at the foramen magnum. The first, a 69-year-old male with a 2-year history of progressive myelopathy, had symptoms unrecognized due to a past history that included spinal caries and congenital dislocation of the hip. The second, a 60-year-old male, had a recurrence of the myelopathy three months after endovascular occlusion of the DAVF feeding artery. Both patients were successfully treated by direct microsurgical interruption of the arterialized medullary vein with functional and radiological improvement. The clinical manifestations of DAVF at the foramen magnum are nonspecific, mimicking those of cervical spondylotic myelopathy or cervical neoplasm. Accurate and early diagnosis followed by complete obliteration of the fistula is mandatory to avoid permanent neurological deficit.

We obtained the venograms using the two-dimensional digital subtraction angiography (2D DSA) images and three dimensional rotation venography (3D RV) images and investigated the potential usefulness of the 3D RV compared with venograms of 2D DSA using the newly developed three-dimensional rotation angiography unit with a flat-panel detector (FPD). This study included 26 sides (11 left, 15 right) in 20 cases (4 males and 16 females) who underwent radiographic examination for management of intracranial tumors and vascular diseases between May 2003 and December 2003. Each patient underwent diagnostic angiography performed on a DSA unit with a FPD. In all patients, the 2D DSA images, including anteroposterior view and lateral view of the carotid artery, were obtained in two stereoscopic views. The 3D RV was used to produce volume-rendered images. Two neuroradiologists investigated the venous configuration of 3D RV compared with that of 2D DSA about the relationship of the venous drainage system on the temporal lobe according to Guppy et al.'s classification. Twenty-four sides of the 26 sides enabled the precious visualization on 3D RV images. In investigation of 2D DSA, 9 sides (37.5%) were classified into type A, 13 (54.2%) into type B, two (8.3%) into type C, and no sides into types D, E, and F. In investigation of 3D RV images, 10 sides (41.7%) were classified into type A, 9 (37.5%) into type B, 1 (4.2%) into type C, 2 (8.3%) into type E, and 2 (8.3%) into type F. Seven of 24 sides demonstrated discrepancy in results between 2D DSA and 3D RV. The 3D RV could be performed by setting the adequate delay in between the injection of the contrast material and starting time of third rotation to acquire the opacified images. In Guppy et al.'s classification, the 3D RV images could demonstrate the precious venous drainage including the venous lakes with use of multiple views and variable reconstruction compared with 2D DSA. Our DSA system with FPD could provide good 3D RV images. These images are very useful for the skull-base surgery because we can understand the three-dimensional vascular anatomy preoperatively.

Glucocorticoids (GCC) generally are administered to patients with brain tumors to relieve neurological symptoms by decreasing the water content in a peritumoral zone of edema. We hypothesized that diffusion imaging and apparent diffusion coefficient (ADC) values could detect subtle changes of water content in brain tumors and in peritumoral edema after GCC therapy. The study consisted of 13 patients with intra-axial brain tumor, and ADC was measured in the tumor, within peritumoral edema, and in normal white matter remote from the tumor before and after GCC therapy. ADC also was measured in normal white matter in four control patients with no intracranial disease who were treated with GCC for other indications. Conventional MR images showed no visually evident interval change in tumor size or the extent of peritumoral edema in any subject after GCC therapy, which nonetheless resulted in a decrease in mean ADC of 7.0% in tumors (P0.05), 1.8% in peritumoral edema (P0.05, not significant) and 5.8% in normal white matter (P0.05). In patients with no intracranial disease, GCC therapy decreased mean ADC in white matter by 5.4% (P0.05). ADC measurement can demonstrate subtle changes in the brain after GCC therapy that cannot be observed by conventional MR imaging. Measurement of ADC proved to be a sensitive means of assessing the effect of GCC therapy, even in the absence of visually discernible changes in conventional MR images.

Following stereotactic radiosurgery (SRS), we examined how to differentiate radiation necrosis from recurrent malignant glioma using positron emission tomography (PET) with 11C-methionine (Met).Met-PET scans were obtained from 11 adult cases of recurrent malignant glioma or radiation injury, suspected on the basis of magnetic resonance images (MRI). Patients had previously been treated with SRS after primary treatment. PET images were obtained as a static scan of 10 minutes performed 20 minutes after injection of Met. We defined two visual grades (e.g., positive or negative Met accumulation). On Met-PET scans, the portion of the tumor with the highest accumulation was selected as the region of interest (ROI), tumor-versus-normal ratio (TN) was defined as the ratio of average radioisotope counts per pixel in the tumor (T), divided by average counts per pixel in normal gray matter (N). The standardized uptake value (SUV) was calculated over the same tumor ROI. Met-PET scan accuracy was evaluated by correlating findings with subsequent histological analysis (8 cases) or, in cases without surgery or biopsy, by the subsequent clinical course and MR findings (3 cases).Histological examinations in 8 cases showed viable glioma cells with necrosis in 6 cases, and necrosis without viable tumor cells in 2 cases. Three other cases were considered to have radiation necrosis because they exhibited stable neurological symptoms with no sign of massive enlargement of the lesion on follow-up MR after 5 months. Mean TN was 1.31 in the radiation necrosis group (5 cases) and 1.87 in the tumor recurrence group (6 cases). Mean SUV was 1.81 in the necrosis group and 2.44 in the recurrence group. There were no statistically significant differences between the recurrence and necrosis groups in TN or SUV. Furthermore, we made a 2 x 2 factorial cross table (accumulation or no accumulation, recurrence or necrosis). From this result, the Met-PET sensitivity, specificity, and accuracy in detecting tumor recurrence were determined to be 100%, 60%, and 82% respectively. In a false positive-case, glial fibrillary acidic protein (GFAP) immunostaining showed a positive finding.There were no significant differences between recurrent malignant glioma and radiation necrosis following SRS in Met-PET. However, this study shows Met-PET has a sensitivity and accuracy for differentiating between recurrent glioma and necrosis, and presents important information for developing treatment strategies against post radiation reactions.

Object. The authors evaluated an alternative method to avoid postoperative posterior tethering of the spinal cord following resection of spinal ependymomas. Methods. Twenty-five patients with spinal ependymoma underwent surgery between 1978 and 2002. There were 16 male and nine female patients whose ages at the time of surgery ranged from 14 to 64 years (mean 41.8 years). The follow-up period ranged from 6 to 279 months (mean 112.4 months). In the initial 17 patients (Group A), the procedure to prevent arachnoidal adhesion consisted of the layer-to-layer closure of three meninges and laminoplasty. In the subsequently treated eight patients (Group B), the authors performed an alternative technique that included pial suturing, dural closure with Gore-Tex membrane—assisted patch grafting, and expansive laminoplasty. In Group A, postoperative adhesion was radiologically detected in eight cases (47%), and delayed neurological deterioration secondary to posterior tethering of the cord was found in five cases. In Group B, there was no evidence of adhesive posterior tethering or delayed neurological deterioration. A significant intergroup statistical difference was demonstrated for radiologically documented posterior tethering (p < 0.05, Fisher exact test). Moreover, patients with radiologically demonstrated posterior tethering suffered a significant delayed neurological functional deterioration (p < 0.01, Fisher exact test). Conclusions. This new technique for closure of the surgical wound is effective in preventing of postoperative posterior spinal cord tethering after excision of spinal ependymoma.

A 63-year-old man presented with subclavian steal syndrome associated with left internal mammary artery (IMA) bypass graft to a coronary artery. He was admitted with a history of oppressive sensation in the chest, dizziness, and light headedness on exertion for 2 weeks in March 2002. He had undergone myocardial revascularization consisting of a left IMA-to-left anterior descending coronary artery graft in April 1988. His blood pressure was 140/70 mmHg in the right arm and 80/64 mmHg in the left arm. Aortic arch arteriography revealed complete occlusion of the left subclavian artery proximal to the left IMA takeoff and subclavian steal with anterograde flow of the left IMA. Percutaneous angioplasty and stent placement with protection of the left IMA bypass graft using a balloon catheter was successfully performed without complication by cerebral or myocardial ischemia. Complete recanalization of the occluded left subclavian artery and anterograde flow of the left vertebral artery were achieved. His symptoms disappeared and blood pressure in the left arm recovered. This variant of coronary subclavian steal might require protection of the left IMA during angioplasty and stent placement.

Two cases of fibrous dysplasia in the skull base bone appeared hypointense on T1- and T2-weighted magnetic resonance imaging, with accumulation of [11C]methyl-L-methionine ([11C]Met) on positron emission tomography (PET). Fibrous dysplasia is a benign bone disorder which is identified by its distinctive radiography, computed tomography, and bone scintigraphy findings. [11C]Met PET may indicate the presence of viable tumor-like cells in fibrous dysplasia.

A 57-year-old woman presented with a dural arteriovenous fistula (AVF) involving the superior sagittal sinus (SSS) based upon serial radiological examinations. Her chief complaints were headache and vomiting. Cerebral angiography and magnetic resonance (MR) venography revealed the sinus thrombosis involving the SSS, the bilateral transverse sinuses (TSs), and the right sigmoid sinus. Her symptoms disappeared after anticoagulant therapy. Follow-up MR venography revealed almost complete recanalization of the occluded sinuses, followed by restenosis of the SSS and the left TS and occlusion of the right TS without symptoms. She developed transient right hemiparesis 13 months after the initial onset. Cerebral angiography revealed a dural AVF involving the SSS with cortical reflux into the left frontoparietal region. The dural AVF was occluded by transarterial and transvenous embolization. Her symptom disappeared during the follow-up period.

A 69-year-old woman had suffered from diplopia on right lateral gaze for the last 4 months due to right abducens nerve paresis. Right carotid angiography showed a cavernous internal carotid artery (ICA) aneurysm of 17 x 16 x 14 mm size and a primitive trigeminal artery (PTA) variant supplying the territory of the posterior inferior cerebellar artery. Intraluminal occlusion of the aneurysm was performed with 15 Guglielmi detachable coils. The flow of the PTA variant and the ICA was preserved. Right abducens nerve paresis improved partially. PTA variant is a primitive artery originating from the cavernous ICA supplying the cerebellum without opacification of the basilar artery. Only four of the 67 cases of PTA variant were associated with an aneurysm of the PTA variant. The possibility of this rare association should be considered when treating cavernous portion aneurysm because of the risk of cerebellar ischemia.

✓ The treatment of spinal intramedullary arteriovenous malformations (AVMs) with a diffuse-type nidus that contains a neural element poses different challenges compared with a glomus-type nidus. The surgical elimination of such lesions involves the risk of spinal cord ischemia that results from coagulation of the feeding artery that, at the same time, supplies cord parenchyma. However, based on evaluation of the risks involved in performing embolization, together with the frequent occurrence of reperfusion, which necessitates frequent reembolization, the authors consider surgery to be a one-stage solution to a disease that otherwise has a very poor prognosis. Magnetic resonance (MR) imaging revealed diffuse-type intramedullary AVMs in the cervical spinal cords of three patients who subsequently underwent surgery via the posterior approach. The AVM was supplied by the anterior spinal artery in one case and by both the anterior and posterior spinal arteries in the other two cases. In all three cases, a posterior median myelotomy was performed up to the vicinity of the anterior median fissure that divided the spinal cord together with the nidus, and the feeding artery was coagulated and severed at its origin from the anterior spinal artery. In the two cases in which the posterior spinal artery fed the AVM, the feeding artery was coagulated on the dorsal surface of the spinal cord. Neurological outcome improved in one patient and deteriorated slightly to mildly in the other two patients. Postoperative angiography demonstrated complete disappearance of the AVM in all cases. Because of the extremely poor prognosis of patients with spinal intramedullary AVMs, this surgical technique for the treatment of diffuse-type AVMs provides acceptable operative outcome. Surgical intervention should be considered when managing a patient with a diffuse-type intramedullary AVM in the cervical spinal cord.

A 66-year-old female developed exophthalmos, impaired visual acuity (perception of light), and diplopia one day after sudden onset of headache. Neurological examination revealed proptosis, chemosis, impaired vision, and ophthalmoplegia. Carotid angiography showed direct carotid-cavernous sinus fistula concomitant with an intracavernous aneurysm on the right side. Intraaneurysmal embolization using the Guglielmi detachable coils (GDCs) via the transarterial route was performed and complete occlusion of the fistula successfully achieved. The neurological deficits resolved completely by 6 months after embolization. Intraaneurysmal GDC embolization via the transarterial route may be an alternative for the treatment of direct carotid-cavernous sinus fistula due to rupture of intracavernous aneurysm.

Pitfall during the embolization and evaluation after the embolization for skull base meningiomas supplied by meningeal arteries of internal carotid artery (ICA) are reported. This study includes 15 cases of skull base meningiomas (two males and 13 females) that supplied by meningeal branches of internal carotid artery. The preoperative embolization was performed by these feeders. MRI findings and serum levels of C-reactive protein (CRP) after the embolization were examined. In ten patients among 15 patients the meningeal branches of ICA were dominant feeders. In ten patients out of 15 patients, the embolization from the meningeal branches of ICA was possible. Eight patients out of these ten patients were suffered from high fever and increase of serum level of CRP after the embolization. During the embolization for skull base meningiomas, the existence of collateral pathways between the ICA system and external carotid artery system were identified. The increase of serum levels of CRP might be recognized in the patients that effective embolization were performed.

Dear Sir, We would like to report a rare complication after transvenous embolization (TVE) of an isolated transverse sigmoid sinus (TSS) dural arteriovenous fistula (dAVF). A 72-year-old male complaining of right pulsatile tinnitus was referred to our hospital. A bruit was identified in the post-auricular region on the right side. There were no neurological deficits. Diagnostic angiography demonstrated a dAVF fed by branches of the occipital and posterior auricular artery and ending in an isolated transverse sigmoid sinus (Fig. 1a). The venous phase of the right common carotid angiography demonstrated absence of opacification of the diseased sinuses and of the ipsilateral inferior petrosal sinus (IPS) and jugular Bulb (JB) (Fig. 1b). TVE was performed under general anesthesia. A microcatheter was navigated to the diseased sinus via contralateral approach. This segment of sinuses was packed with detachable microcoils (GDC®/Targets Therapeutics, Fremont, CA, USA). Final control angiography showed complete obliteration of the shunt (Fig. 2). The pulsatile tinnitus disappeared immediately after the procedure. On postoperative day 1, the patient complained of dizziness, but MR with diffusion weighted images showed no abnormal findings. The dizziness improved within 10 days. After 10 days of hospitalization, a sudden hearing loss occurred in the right ear. Puretone audiography revealed a sensory neural hearing loss (SNHL) of 40 dB. A tentative diagnosis of sudden SNHL (SSNHL) was made by the ENT specialists. Intravenous drip infusion of corticosteroids and low molecular dextrin was initiated. Two weeks later, hearing loss had improved with 15 dB. To the best of our knowledge, no previous reports have described SNHL after TVE of a dAVF. When considering the etiology of the hearing loss in our case, two aspects must be discussed. First it should be made out whether this SNHL occurred incidentally or as a consequence of the procedure. Secondly, if the embolization caused the SNHL, the potential pathogenesis and clinical significance of the SNHL should be investigated. If the hearing loss was coincidental, the diagnosis of SSNHL would be the most likely diagnosis. Nevertheless, in the literature, the incidence of SSNHL is reported as low as 5–20/100,000 person-years [1, 2]. Moreover, it is highly unlikely that ipsilateral SSNHL would occur incidentally within 10 days after TVE. Therefore, it seems more likely that this SNHL has arisen as a consequence of the procedure. Although various reports have described SNHL caused by anesthesia [3], radiation [4], and contrast medium administration [5], these potential causes of hearing loss seem not to match for our case. Therefore, we considered that TVE itself must be responsible for this SNHL. Anatomically, the inner ear has two main venous drainage routes: the vein of the vestibular aqueduct (VVAQ) draining into the vertical portion of the sigmoid sinus or superior petrosal sinus (SPS); and the vein of cochlear aqueduct (VCAQ) draining into the JB or the caudal end of the IPS (Fig. 3a) [6]. Watanabe et al. reported the precise venous drainage of the inner ear in guinea pigs [7]. They reported the presence of minor collateral vessels between the VCAQ and the mucoperiosteal veins of the middle ear, which act as collateral channels in the event of venous congestion of the inner ear [7]. S. Yamauchi (*) :A. Nishio Department of Neurosurgery, Hokuto Hospital, 7-5 Inada, Obihiro, Hokkaido 080-0033, Japan e-mail: ymailadd@silver.ocn.ne.jp

To investigate imaging characteristics of post-embolised meningioma and to determine if SW imaging can delineate tumour ischaemia. Sixteen patients were studied before and after preoperative embolisation therapy (8 histopathologically determined with ischaemia, 8 with non-ischaemia). In each patient, a slice-wise ROI for the entire tumour was established, and histogram variables (mean, SD, minimum, maximum, histogram width, mode, and peak height) of SW, ADC, CBV, CBF, MTT, and TTP maps were compared between ischaemic and non-ischaemic groups. Changes in SW histogram were correlated with histopathological characteristics. Signal intensity on the SW map tended to decrease in the ischaemic group and partially increased in the non-ischaemic group. A similar trend was observed on the ADC map. The PW histogram showed an MTT increase in ischaemic group; however, CBV did not show significant changes between ischaemic and non-ischaemic groups. Microhaemorrhage was slightly correlated with Δpeak height in the SW histogram. Post-embolisation changes of intrinsic T2*-weighted MR contrasts on SW map are most likely associated with alterations in deoxyhaemoglobin levels and arterial blood flow. • Endovascular embolisation is now accepted as an adjuvant therapy for intracranial meningioma. • Magnetic resonance imaging is used to assess the effects of embolisation. • Unenhanced susceptibility-weighted MRI can delineate ischaemic and non-ischaemic areas. • Signal changes at SW imaging are associated with diffusion and perfusion abnormalities. • Three-dimensional high-resolution SW imaging offers a new imaging biomarker in assessing ischaemia.

A 55-year-old man presented with intracerebral hemorrhage (ICH) without subarachnoid hemorrhage (SAH) manifesting as acute onset of consciousness disturbance and right hemiparesis. Computed tomography showed ICH mainly localized in the left putamen, but no evidence of SAH. Magnetic resonance angiography demonstrated a cerebral aneurysm originating from the bifurcation of the left internal carotid artery, which was considered to be responsible for the ICH. The patient underwent emergent intravascular surgery for coil embolization of the aneurysm, and his neurological symptoms gradually recovered with rehabilitation after surgery. Although ICH without SAH is a rare presentation of cerebral aneurysm, ruptured cerebral aneurysm should be considered as a potential cause of ICH. The localization and extent of ICH may be suggestive of latent cerebral aneurysm in such cases.

A 61-year-old man presented with a severe external carotid artery (ECA) stenosis with concomitant ipsilateral internal carotid artery (ICA) occlusion manifesting as amaurosis fugax. The left ophthalmic artery was supplied from the left ECA. The left intracranial ICA was supplied by the collateral flow from the contralateral ICA and ipsilateral ECA through the ophthalmic artery. The left vertebral artery also participated in the latter collateral pathway through the left occipital artery and ascending pharyngeal artery. Percutaneous revascularization of the ECA was performed using a nitinol self-expanding stent. To prevent embolic complications through the ophthalmic or vertebral arteries, distal protection was performed using a balloon. During a 22-month follow-up period, the patient was completely free from any ocular or neurological symptoms. The present case of severe ECA stenosis with ipsilateral ICA occlusion showed that percutaneous balloon angioplasty with stenting is feasible and effective. This intervention requires cautious evaluation of the anastomotic pathways connecting the ECA to the cerebral circulation to avoid embolic complications.

The efficacy of selecting non-responders to intravenous recombinant tissue plasminogen activator (rt-PA) for mechanical clot disruption (MCD) was investigated based on cerebral angiography in the acute stage following rt-PA therapy. rt-PA therapy using 0.6 mg/kg was performed in eligible patients within 3 hours of onset. Patients who did not show recanalization on cerebral angiography 1 hour after rt-PA initiation immediately underwent MCD. Clinical outcome was evaluated by National Institutes of Health Stroke Scale (NIHSS) score at baseline, 24 hours, and 1 month, and by modified Rankin scale (mRS) score at 3 months. Eighteen patients were initially treated with intravenous rt-PA, with mean time from stroke onset to rt-PA therapy of 120 +/- 27 minutes. Eight of these patients underwent MCD. Seven of these eight patients had complete recanalization. Time to recanalization by percutaneous transluminal angioplasty from stroke onset was 258 +/- 59 minutes. Final recanalization was achieved in 16 of the 18 patients. Baseline NIHSS score improved significantly at 1 month (median from 22.5 to 4). Twelve of the 18 patients treated according to our protocol were classified as independent (mRS scores 0-2). No patients had symptomatic hemorrhage. MCD for non-responders determined by cerebral angiography at the end of intravenous rt-PA infusion can decrease the time to recanalization and improve recanalization rates, leading to good clinical outcome after acute stroke.

We describe a very rare case of anomalous origin of the anterior choroidal artery. In our case the anterior choroidal artery arises from the internal carotid artery proximal to the posterior communicating artery.

The authors report a case of subarachnoid hemorrhage and spinal root injury caused by an acupuncture needle buried in the posterior neck about 30 years before onset. A 33-year-old female presented with sudden onset of severe occipital headaches. Plain x-ray films of the cervical spine revealed a fine gold needle, about 1.5 cm in length, between the C1 and C2 vertebrae. The needle was piercing the spinal nerve root through the dural vein, and was removed. Postoperatively, the pain exacerbated by neck movement disappeared.

In the management of skull base chordomas, surgical treatment is essential to achieve long-term control. A petroclival chordoma growing laterally in the skull base is one of the most challenging tumors for neurosurgeons. We have treated petroclival chordomas based on the principle of maximal surgical resection of the tumor with minimal morbidity. Lateral skull base approaches were used to approach petroclival chordomas in eight patients. The surgical procedure involved removal of soft tumor tissue and extensive drilling of adjacent bony structures. Gross total resection of the tumor was achieved in six patients. Subtotal resection in the remaining two patients was associated with acceptable morbidity. In cases of petroclival chordomas, lateral skull base approaches can be used as a primary procedure, although those approaches may be associated with high rates of morbidity and mortality.

The histological features of arterialized medullary vein (MV) in spinal dural arteriovenous fistulas (SDAVF) were studied in five consecutive patients who presented with progressive congestive myelopathy. Retrograde venous filling on preoperative angiography was recognized as being severe in 3 cases and moderate in 2 cases. Direct intradural interruption of the arterialized MV was performed in all patients. The arterialized MV was sampled and examined histologically to determine the percentage of the hyperplasia of venous wall (hypertrophic ratio). Histological examination of arterialized MV showed that hypertrophic alteration of venous wall structure was due to hyperplasia of elastic fibers, ranging from 41 to 82%. Patients with angiographically severe venous hypertension tended to have a higher hypertrophic ratio than patients with moderate venous hypertension. Our observations support the clinical concept that long-standing arterial stress in the spinal venous circulation causes histological alterations of spinal vascular structure associated with the progression of venous hypertension. We suggested that possibly the histological parameter can be used for predicting neurological recovery after occlusion of the fistulas.

We report a dural arteriovenous fistula (AVF) that developed at a site on the midline dorsal surface of the dura mater that had been damaged by repeated lumbar punctures. A 61-year-old male patient had undergone repeated lumbar punctures and discectomy for severe lumbago 40 years before the present admission. After surgery, the lumbago symptoms resolved. However, 30 years after the operation, he started to experience dysaesthesia, motor weakness in both legs, and urinary disturbance. Physical examination revealed bilateral leg weakness, diminished deep tendon reflexes in the patellar and Achilles tendons bilaterally, and decreased superficial sensation below L1. Magnetic resonance imaging revealed swelling with intramedullary high intensity and multiple flow voids around the conus and spinal cord on T(2)-weighted images, and adhesive arachnoiditis. Spinal angiography revealed an AVF between the left lateral sacral artery and the S1 radicular vein at the site of the previous operation. Surgery was conducted to carry out excision of the dural AVF at the shunting point, the arterialized intradural vein, and lysis of the arachnoiditis. This case of dural AVF may have been caused by repeated lumbar punctures.

Positron emission tomography (PET) imaging is in common use preoperatively to clinically evaluate patients who present with central nervous system mass lesions. The usefulness of PET is also recognized as a method to detect intracranial tumorous lesions. A number of papers report that some inflammatory processes also showed the uptake of Fluorine-18-Fluorodeoxyglucose (FDG) and Carbon-11-Methionine (Met) tracers. We performed two PET studies before and after treatment in 4 patients with brain abscess. PET showed the uptake of both tracers to the brain abscess before treatment. The area showing an increased uptake of Met corresponded closely to the enhanced area on both CT and MR images. FDG-PET visually showed an uptake of FDG in a small area corresponding to an enhanced lesion within the CT and MR images. After treatment the area of lesions became small on enhancement CT or MRI and both PET studies showed reduced lesion and decreased uptake. The mechanism of Met uptake in the inflammatory area may be related to the higher metabolic rate and the active transport of amino acids as well as disruption of the blood brain barrier. Furthermore, it appears that the mechanism of FDG uptake is also related to a higher metabolic rate and, in addition, is related to the increased density of inflammatory cells. PET studies, more directly, reflect the degree of inflammatory response in brain abscess than enhancement CT or MRI. Therefore, PET is useful in detecting the inflammatory lesion and assessing the clinical effects of antibiotics treatment on brain abscesses.

A spinal intramedullary arteriovenous malformation (AVM) associated with a radicular arteriovenous fistula (AVF) is reported. The patient had mild myelopathy and low back pain. Spinal angiography revealed the AVM fed by the anterior spinal artery via left T10, T11 and right L1 radiculomedullary arteries and the radiculopial arteries of left L1, L2 and right T11, L3 levels and the radicular AVF at the left L4 level. There were three radiculomedullary arteries within four levels in our case. This spinal AVM associated with a radicular AVF is considered a genetic nonhereditary lesion with metameric link.

Object. The authors describe a new surgical technique for cervical laminoplasty that was performed in 25 patients. The posterior elements along with the various ligaments are removed en bloc and are stabilized in a lift-up position by placing hydroxyapatite (HA) laminar spacers and titanium miniplates and screws. The procedure and clinical results are discussed. Methods. The posterior spinal elements, including the lamina(e), spinous process(es), and various attached ligaments, are removed en bloc by incising the lamina in its lateral aspect. Trapezoid-shaped HA spacers are placed between the cut ends of the laminae or between the laminae and lateral masses bilaterally at each level. Malleable titanium miniplates and screws are used for fixation of the spacers. The fixation of transected laminae was judged to be successful. Postoperative care included application of a soft neck collar for 1 week but no further restriction of activity. Surgery-related outcome was assessed in the 21 patients who attended more than 6 months of follow up after laminoplasty. There were 18 men and three women who ranged in age from 27 to 81 years. Cervical stenotic myelopathy was demonstrated in 15 patients who underwent decompressive and expansive laminoplasty, and spinal tumors were documented in six patients who underwent a nonexpansive laminoplasty. Postoperative and follow-up computerized tomography scans demonstrated no hardware failure. Bone formation around the spacers was observed either at 6- or at 9-month follow-up examination in all 21 patients. Fusion of the reconstructed laminae was found to be completed at 12 months in all 18 patients able to attend follow up for this duration. Spinal alignment and the range of motion of the cervical spine were well preserved. In patients with stenotic cervical myelopathy, neurological and anatomical outcome of canal expansion were satisfactory. Conclusions. This technique enables rigid laminoplasty while maintaining anatomical and biomechanical integrity of posterior elements of cervical spine. Expansive and nonexpansive laminoplasty procedures are possible.

Background: A dural arteriovenous fistula (AVF) involving the transverse-sigmoid (T-S) sinus which is occluded at its proximal and distal ends i.e., an isolated sinus, runs the risk of haemorrhaging or causing serious neurological deficits as a result of its retrograde leptomeningeal venous drainage. While lesions of this type have not been considered to be treatable by percutaneous, transvenous embolisation, this paper challenges this view. Case Presentation: Two middle-aged men with dural AVFs involving the isolated left T-S sinus presented with motor aphasia due to focal brain edema or haemorrhage. Under local anaesthesia, transfemoral, transvenous embolisation was performed with a microcatheter that was passed through the occluded proximal transverse sinus from the right (contralateral) side. The isolated sinus was then occluded with platinum coils. This embolisation resulted in angiographic and clinical cure of dural AVFs in both patients. Interpretation: Transfemoral, transvenous embolisation is a therapeutic alternative for the treatment of dural AVFs involving the isolated T-S sinus. Embolisation obviates the need for craniotomy and general anaesthesia, which are required for the established modes of treatment, i.e., direct surgery or direct percutaneous sinus packing.

Two cases of fibrous dysplasia in the skull base bone appeared hypointense on T1- and T2-weighted magnetic resonance imaging, with accumulation of [11C]methyl-L-methionine ([11C]Met) on positron emission tomography (PET). Fibrous dysplasia is a benign bone disorder which is identified by its distinctive radiography, computed tomography, and bone scintigraphy findings. [11C]Met PET may indicate the presence of viable tumor-like cells in fibrous dysplasia.

A 57-year-old woman presented with a dural arteriovenous fistula (AVF) involving the superior sagittal sinus (SSS) based upon serial radiological examinations. Her chief complaints were headache and vomiting. Cerebral angiography and magnetic resonance (MR) venography revealed the sinus thrombosis involving the SSS, the bilateral transverse sinuses (TSs), and the right sigmoid sinus. Her symptoms disappeared after anticoagulant therapy. Follow-up MR venography revealed almost complete recanalization of the occluded sinuses, followed by restenosis of the SSS and the left TS and occlusion of the right TS without symptoms. She developed transient right hemiparesis 13 months after the initial onset. Cerebral angiography revealed a dural AVF involving the SSS with cortical reflux into the left frontoparietal region. The dural AVF was occluded by transarterial and transvenous embolization. Her symptom disappeared during the follow-up period.

The usefulness of multi-planar reconstruction (MPR) images of three-dimensional computed tomographic angiography (3D-CTA) for the diagnosis of internal carotid artery (ICA) aneurysms is described. Eleven unruptured ICA aneurysms including six cases of IC-cavernous aneurysm, two cases of IC-ophthalmic artery aneurysm, two cases of IC-posterior communicating artery aneurysm and one cases of IC-anterior choroidal artery aneurysm, were examined by magnetic resonance angiography (MRA), digital subtraction angiography (DSA), 3D-CTA and its MPR images. 3D-CTA and DSA were useful to identify the aneurysmal neck in small aneurysms, but it was difficult to identify the aneurysmal neck in small aneurysms by 3D-CTA-MPR images. DSA and MRA were not useful for identifying the aneurysmal neck in aneurysms more than 10 mm in diameter, as a precise viewing of the neck could not be found due to their large size. For large aneurysms, neither was 3D-CTA useful for identifying the aneurysmal neck when their large size and surrounding bony structures overlapped the aneurysmal neck. On the other hand, 3D-CTA-MPR was very useful for identifying the aneurysmal neck without overlapping by surrounding bony structures. 3D-CTA-MPR images clearly visualized the calcification of the wall. 3D-CTA-MPR images are obtained from 3D-CTA source images without any additional stress to the patients, and they are more useful for the diagnosis as well as demonstration of the aneurysmal neck particularly in more than large aneurysms.

Eleven patients with so-called “vein of Galen aneurysms” are reported, six of whom presented with vein of Galen aneurysmal malformations (four with choroidal type and two with mural type malformations). The remaining five patients presented with vein of Galen aneurysmal dilatations secondarily due to an arteriovenous malformation in one patient, an arteriovenous fistula in another, dural arteriovenous fistulas in two patients, and a varix in another. Treatments for these patients were individualised with consideration given to the clinical manifestations and the angioarchitecture of their lesions. Endovascular Intervention played a critical role in the treatment of these vein of Galen aneurysms.