Estimation of the rupture point of the craniovertebral junction intradural arteriovenous fistula with vessel wall magnetic resonance image and its pathological findings: A case report.

Background: Arteriovenous fistulas (AVFs) of the craniocervical junction (CCJ) and intradural AVFs are often associated with aneurysms and varics, and it is sometimes difficult to identify the ruptured point on radiological images. We report a case in which vessel wall magnetic resonance image (VW-MRI) was useful for identifying the ruptured point at the CCJ AVF. Case Description: A 70-year-old man presented with a sudden onset of headache. He had Glasgow Coma Scale E4V5M6, world federation of neurosurgical societies (WFNS) Grade I. Fisher group 3 subarachnoid hemorrhage and hydrocephalus were found on head computed tomography. Cerebral angiography showed a spinal AVF at the C1 level of the cervical spine. Magnetic resonance image-enhanced motion sensitized driven equilibrium (MSDE-method showed an enhancing effect in part of the AVF draining vein, but the vascular architecture of this lesion was indeterminate. We performed continuous ventricular drainage for acute hydrocephalus and antihypertensive treatment. Cerebral angiography was performed 30days after the onset of the disease, and was revealed an aneurysmal structure in a portion of the AVF draining vein, which VW-MRI initially enhanced. On the 38th day after onset, he underwent direct surgery to occlude the AV fistula and dissect the aneurysmal structure. Histopathology showed that the aneurysmal structure was varices with lymphocytic infiltration, and hemosiderin deposition was observed near the varices. Conclusion: Recently, VW-MRI has been reported to show an association between the enhancement of varices in dural AVF and rupture cases. VW-MRI, especially the enhanced MSDE method, may be useful in estimating the ruptured point in arteriovenous shunt disease.

Thrombolysis for Acute Wake-Up and Unclear-Onset Strokes with Alteplase at 0.6 mg/kg in Clinical Practice: THAWS2 Study.

INTRODUCTION: The aim of this study was to determine the safety and efficacy of intravenous (IV) alteplase at 0.6 mg/kg for patients with acute wake-up or unclear-onset strokes in clinical practice. METHODS: This multicenter observational study enrolled acute ischemic stroke patients with last-known-well time >4.5 h who had mismatch between DWI and FLAIR and were treated with IV alteplase. The safety outcomes were symptomatic intracranial hemorrhage (sICH) after thrombolysis, all-cause deaths, and all adverse events. The efficacy outcomes were favorable outcome defined as an mRS score of 0-1 or recovery to the same mRS score as the premorbid score, complete independence defined as an mRS score of 0-1 at 90 days, and change in NIHSS at 24 h from baseline. RESULTS: Sixty-six patients (35 females; mean age, 74 ± 11 years; premorbid complete independence, 54 [82%]; median NIHSS on admission, 11) were enrolled at 15 hospitals. Two patients (3%) had sICH. Median NIHSS changed from 11 (IQR, 6.75-16.25) at baseline to 5 (3-12.25) at 24 h after alteplase initiation (change, -4.8 ± 8.1). At discharge, 31 patients (47%) had favorable outcome and 29 (44%) had complete independence. None died within 90 days. Twenty-three (35%) also underwent mechanical thrombectomy (no sICH, NIHSS change of -8.5 ± 7.3), of whom 11 (48%) were completely independent at discharge. CONCLUSIONS: In real-world clinical practice, IV alteplase for unclear-onset stroke patients with DWI-FLAIR mismatch provided safe and efficacious outcomes comparable to those in previous trials. Additional mechanical thrombectomy was performed safely in them.

Intracranial parenchymal capillary hemangioma: A case report.

Background: Capillary hemangioma is a rare benign hemangioma that occurs in the soft tissues of the skin, orbit, head, and neck. Intracranial cases, especially intraparenchymal cases, are extremely rare. In this study, we report the course of an intracranial parenchymal capillary hemangioma with left mild motor paresis and involuntary movements of the left upper extremity and was successfully treated by surgical resection, including radiological and pathological examinations. Case Description: This is a case of a 60-year-old woman who presented with motor weakness and involuntary movement of the left upper extremity. Computed tomography and magnetic resonance imaging revealed the right frontal hemorrhagic mass lesion without enhancement of contrast medium. Cerebral digital subtraction angiography showed no vascular stain and abnormal arteriovenous shunt. Preoperatively, we diagnosed cavernous hemangioma with a hemorrhagic component located in the right motor cortex. Because this case was symptomatic, we performed a craniotomy and gross total resection of the right frontal lesion. The diagnosis of capillary hemangioma was made by histological examination, including immunohistological study. Conclusion: Because intraparenchymal capillary hemangiomas are difficult to diagnose with preoperative imaging, surgical treatment, and histopathological examination are important.

Late-onset aqueductal membranous occlusion treated neuroendoscopic procedure and consideration of its pathological findings: A case report.

Background: Aqueduct of Sylvius stenosis/obstruction interferes with cerebrospinal fluid (CSF) flow and leads to the non-communicating hydrocephalus. Acquired non-neoplastic causes of aqueduct of Sylvius stenosis/ obstruction include simple stenosis, gliosis, slit-like stenosis, and septal formation, but the detailed mechanisms are not clear. In the present study, we experienced a case of late-onset aqueductal membranous occlusion (LAMO) successfully treated by neuroendoscopic procedure, which allowed us to examine the pathology of the membranous structures of the aqueduct of Sylvius occlusion. Case Description: A 66-year-old woman presented with gradually progressive gait disturbance, cognitive dysfunction, and urinary incontinenc. Brain magnetic resonance imaging (MRI) showed enlargement of the bilateral lateral ventricles and the third ventricle without dilatation of fourth ventricle, and heavily T2-weighted images showed an enlarged aqueduct of Sylvius and a membranous structure at its caudal end. Gadolinium contrast-enhanced T1-weighted images showed no neoplastic lesions. We diagnosed this case that the hydrocephalus due to late-onset idiopathic aqueductal stenosis or LAMO and the patient underwent endoscopic third ventriculostomy and endoscopic aqueduct oplasty. Membranous tissue specimens were obtained from the occluded aqueduct of Sylvius at the time of treatment. Histopathological examination revealed gliosis, and inside the gliosis, there were cell clusters that appeared to be ependymal cells and were corpora amylacea. We confirmed CSF flow at the site of obstruction of the aqueduct of Sylvius and the stoma of the third ventricle floor by MRI images. Her symptoms were improved immediately. Conclusion: We experienced a case of LAMO successfully treated by neuroendoscopic procedure, which allowed us to examine the pathology of the membranous structure of the aqueduct of Sylvius. The pathological study of LAMO is rare, and we report it, including a review of the literature.

Postpartum reversible cerebral vasoconstriction with cortical subarachnoid hemorrhage and posterior reversible encephalopathy syndrome concomitant with vertebral artery dissection diagnosed by MRI MSDE method: A case report and review of literature.

Headache is one of the most common symptoms encountered during the postpartum period. The cause may be unknown, or the following illnesses are possible: cervical artery dissection (CAD), reversible posterior cerebral encephalopathy syndrome (PRES), and reversible cerebral vasoconstrictor syndrome (RCVS). It is suggested that they are interrelated and share a similar mechanism such as small vessel endothelial dysfunction, deficiencies in self-regulation, and decreased sympathetic innervation of the posterior circulation. However, there are few reports of neuroradiological findings. We experienced a rare case of multiple postpartum vascular disease occurring at the same time. A 38-year-old woman suddenly developed thunderclap headache after giving birth. She was clear and had no neuropathy. Computed tomography revealed subarachnoid hemorrhage, including the cortical surface of the frontal lobe. Magnetic resonance image fluid-attenuated inversion recovery revealed high-intensity area in the bilateral basal ganglia and right occipital cortex. Angiography showed "string sausage" and extracranial left vertebral artery stenosis, but no aneurysm. Based on the clinical course and neuroradiological findings, we diagnosed her as postpartum vascular disease including CAD, PRES, RCVS, and cortical subarachnoid hemorrhage (SAH). Three-dimensional black blood T1-weighted images using a motion-sensitized driven equilibrium three-dimensional turbo spin echo (MSDE) sequencing method revealed an intramural hematoma consistent with the extracranial vertebral artery. After 3 months, MSDE lost its abnormal signal. Our case was rare in that multiple phenomena of postpartum vascular disease occurred at the same time. In particular, we could reveal that this speculation was reversible in the MRI MSDE sequencing.

Ingenuity using 3D-MRI fusion image in evaluation before and after microvascular decompression for hemifacial spasm.

Background: Hemifacial spasm (HFS) is most often caused by blood vessels touching a facial nerve. In particular, responsible vessels compress the root exit zone (REZ) of the facial nerve. Although we recognize these causes of HFS, it is difficult to evaluate the findings of precise lesion in radiological imaging when vessels compress REZ. Hence, we tried to obtain precise images of pre- and postoperative neuroradiological findings of HFS by creating a fusion image of MR angiography and the REZ of facial nerve extracted by magnetic resonance imaging (MRI) diffusion tensor image (DTI). Case Description: A 52-year-old woman had a 2-year history of HFS on the left side of her face. It was confirmed that the left vertebral artery and anterior inferior cerebellar artery were presented near the facial nerve on MRI. REZ of the facial nerve was visualized using DTI and fusion image was created with vascular components, making it possible to recognize the relationship between compression vessels and REZ of the facial nerve in detail. She underwent microvascular decompression and her HFS completely disappeared. We confirmed that the REZ of the facial nerve was decompressed by MRI imaging, in the same way as before surgery. Conclusion: We describe that the REZ of facial nerve and compressive vessels was delineated in detail on MRI and this technique is useful for pre- and postoperative evaluation of HFS.

Endovascular Treatment of Hemifacial Spasm Associated with a Tentorial DAVF Using Transarterial Onyx Embolization: A Case Report.

Objective: We describe a patient treated with transarterial Onyx embolization for a tentorial dural arteriovenous fistula (DAVF) who presented with hemifacial spasm (HFS). Case Presentation: A 56-year-old man suffered from right blepharospasm for 4 years, and the symptom gradually spread to the right side of his face with oculo-oral synkinesis. MRI of the brain revealed abnormal multiple flow voids at the surface of brainstem and cerebellar hemisphere. MRA (time of flight) and spoiled gradient recalled echo-revealed abnormal vessels at the posterior fossa indicated arteriovenous shunting. 3D-MRI fusion images showed that a dilated vein was in contact with the root exit zone (REZ) of the right facial nerve. The right carotid angiography displayed a complex tentorial DAVF on the right side. There were multiple feeding vessels drained to the tentorial sinus at the point where the inferior cerebellar vermian vein met, and severe venous congestion was noted. We diagnosed a tentorial DAVF and thought that this was responsible for the right HFS. We used neuroendovascular treatment for this lesion. After transarterial Onyx embolization, his right HFS diminished. MRI after treatment showed that the vein in contact with the REZ of the right facial nerve had shrank. Conclusion: We experienced a rare case of HFS associated with a DAVF. Our case supports that transarterial Onyx embolization can treat HFS associated with a tentorial DAVF. It is the first description of successful treatment that could be confirmed through postoperative MRI.

Bioresorbable plate fracture after cranioplasty caused by head injury: a pediatric case.

BACKGROUND: Recently, bone fixation materials have been developed as surgical materials. Bioabsorbable materials offer several advantages over other materials and are widely used. We report a rare case of the fracture of bioresorbable plates caused by head injury and describe some considerations. CASE DESCRIPTION: A 6-year-old boy suffered from consciousness disturbance. He was admitted to our hospital and diagnosed with left frontal subcortical hemorrhage due to ruptured arteriovenous malformation (AVM). He received the surgery of removal of the AVM with decompressive craniectomy. He was discharged without any neurologic deficit and underwent the cranioplasty 4 months after the initial surgery. Two months after the last treatment, he was fallen and hit his left frontal head. The next day, he noticed an abnormal bulge in the injured area. We diagnosed the bulging as cerebrospinal fluid leakage because of the dural tear. The repairment of dural tear was performed. We found that two bioresorbable plates used by cranioplasty were both cracked, and the dura mater beneath them was torn. We repaired the damaged dura with an artificial dura mater. After surgery, cerebrospinal fluid leakage did not occur. CONCLUSION: It has been reported that the durability of bioresorbable plates is no less than that of titanium plates. We experienced a relatively rare case in which bioabsorbable plate used for bone fixation was damaged due to head trauma. After craniotomy or cranioplasty using bioresorbable plates, special attention should be paid to head trauma that involves bone flap sinking force and side bending stress.

Coil embolization of subarachnoid hemorrhage with ruptured persistent primitive olfactory artery aneurysm.

BACKGROUND: Persistent primitive olfactory artery (PPOA) is a rare anomaly of the anterior cerebral artery. We experienced a rare case of subarachnoid hemorrhage caused by a ruptured saccular aneurysm of PPOA. CASE DESCRIPTION: A 72-year-old man was transported to our hospital with sudden headache. On examination, World Federation of Neurological Surgeons scale was Grade I, and computed tomography of the head showed subarachnoid hemorrhage in Fisher Group 3. Cerebral angiography showed left PPOA and a 4-mm saccular aneurysm at the hairpin turn. No other abnormalities causing bleeding were observed. Based on these findings, subarachnoid hemorrhage due to a ruptured PPOA aneurysm was diagnosed. As the patient had a ventilatory defect due to emphysema, direct approach to the lesion would have been difficult and an endovascular surgery was performed. Three coils were inserted into the aneurysm, and complete occlusion was achieved. Cerebral vasospasm was not observed, and the patient was discharged 1 month after surgery without any neurologic deficit. CONCLUSION: Most aneurysms of the PPOA are formed at the hairpin turn, as observed in our patient; therefore, a hemodynamic mechanism may be involved in the etiology. To the best of our knowledge, there is no report on treatment using intra-aneurysmal coil embolization, indicating that ours was the first case. As the long-term outcome of intra-aneurysmal coil embolization for PPOA aneurysm is unknown, careful follow-up will be necessary in the future.

Clinical Trial of the New Stent Retriever Tron FX for both Proximal and Distal Intracranial Large Vessel Occlusions.

BACKGROUND: In all of randomized controlled trials of mechanical thrombectomy, the target vessels were proximal. Herein we report a clinical trial of the Tron FX stent retriever, including the smallest size of 2/15 mm for distal intracranial large vessel occlusion (LVO). OBJECTIVE: Eligible patients presented within 8 h of onset with proximal or distal LVOs, and the Tron FX 4/20 mm or 2/15 mm were used as the first-line device. METHODS: The primary endpoints were rate of modified Thrombolysis in Cerebral Infarction (mTICI) grade 2a-3 immediately after using Tron FX only, and mortality rate 90 d. We compared the outcomes between sizes 4/20 and 2/15 mm. RESULTS: The clinical trial was conducted in 50 cases, of which 44% presented with distal LVO and 15 cases were treated using only Tron FX 2/15 mm. The overall rate of mTICI grade 2a-3 was 80.0% (75.8% with Tron FX 4/20 mm, and 86.7% with 2/15 mm), and a 90-day modified Rankin Scale ≤ 2 or improvement of National Institute of Health Stroke Scale after thrombectomy ≥ 10 was achieved in 66.7% of cases (61.3% with Tron FX 4/20 mm, and 80.0% with 2/15 mm). The overall 90-day mortality rate was 8.0%, and symptomatic intracranial hemorrhage within 24 h occurred in 2.0% of cases. CONCLUSION: In this clinical trial using the Tron FX, which included the size of 2/15 mm for distal LVO, its efficacy was similar and its safety was superior compared with previous studies.

Magnetic Resonance Imaging-Guided Thrombolysis (0.6 mg/kg) Was Beneficial for Unknown Onset Stroke Above a Certain Core Size: THAWS RCT Substudy.

BACKGROUND AND PURPOSE: We determined to identify patients with unknown onset stroke who could have favorable 90-day outcomes after low-dose thrombolysis from the THAWS (Thrombolysis for Acute Wake-Up and Unclear-Onset Strokes With Alteplase at 0.6 mg/kg) database. METHODS: This was a subanalysis of an investigator-initiated, multicenter, randomized, open-label, blinded-end point trial. Patients with stroke with a time last-known-well >4.5 hours who showed a mismatch between diffusion-weighted imaging (DWI) and fluid-attenuated inversion recovery were randomly assigned (1:1) to receive alteplase at 0.6 mg/kg intravenously or standard medical treatment. The patients were dichotomized by ischemic core size or National Institutes of Health Stroke Scale score, and the effects of assigned treatments were compared in each group. The efficacy outcome was favorable outcome at 90 days, defined as a modified Rankin Scale score of 0 to 1. RESULTS: The median DWI-Alberta Stroke Program Early CT Score (ASPECTS) was 9, and the median ischemic core volume was 2.5 mL. Both favorable outcome (47.1% versus 48.3%) and any intracranial hemorrhage (26% versus 14%) at 22 to 36 hours were comparable between the 68 thrombolyzed patients and the 58 control patients. There was a significant treatment-by-cohort interaction for favorable outcome between dichotomized patients by ASPECTS on DWI (P=0.026) and core volume (P=0.035). Favorable outcome was more common in the alteplase group than in the control group in patients with DWI-ASPECTS 5 to 8 (RR, 4.75 [95% CI, 1.33-30.2]), although not in patients with DWI-ASPECTS 9 to 10. Favorable outcome tended to be more common in the alteplase group than in the control group in patients with core volume >6.4 mL (RR, 6.15 [95% CI, 0.87-43.64]), although not in patients with volume ≤6.4 mL. The frequency of any intracranial hemorrhage did not differ significantly between the 2 treatment groups in any dichotomized patients. CONCLUSIONS: Patients developing unknown onset stroke with DWI-ASPECTS 5 to 8 showed favorable outcomes more commonly after low-dose thrombolysis than after standard treatment. Registration: URL: https://www.clinicaltrials.gov; Unique Identifier: NCT02002325. URL: https://www.umin.ac.jp/ctr; Unique Identifier: UMIN000011630.

Thrombolysis With Alteplase at 0.6 mg/kg for Stroke With Unknown Time of Onset: A Randomized Controlled Trial.

Background and Purpose- We assessed whether lower-dose alteplase at 0.6 mg/kg is efficacious and safe for acute fluid-attenuated inversion recovery-negative stroke with unknown time of onset. Methods- This was an investigator-initiated, multicenter, randomized, open-label, blinded-end point trial. Patients met the standard indication criteria for intravenous thrombolysis other than a time last-known-well >4.5 hours (eg, wake-up stroke). Patients were randomly assigned (1:1) to receive alteplase at 0.6 mg/kg or standard medical treatment if magnetic resonance imaging showed acute ischemic lesion on diffusion-weighted imaging and no marked corresponding hyperintensity on fluid-attenuated inversion recovery. The primary outcome was a favorable outcome (90-day modified Rankin Scale score of 0-1). Results- Following the early stop and positive results of the WAKE-UP trial (Efficacy and Safety of MRI-Based Thrombolysis in Wake-Up Stroke), this trial was prematurely terminated with 131 of the anticipated 300 patients (55 women; mean age, 74.4±12.2 years). Favorable outcome was comparable between the alteplase group (32/68, 47.1%) and the control group (28/58, 48.3%; relative risk [RR], 0.97 [95% CI, 0.68-1.41]; P=0.892). Symptomatic intracranial hemorrhage within 22 to 36 hours occurred in 1/71 and 0/60 (RR, infinity [95% CI, 0.06 to infinity]; P>0.999), respectively. Death at 90 days occurred in 2/71 and 2/60 (RR, 0.85 [95% CI, 0.06-12.58]; P>0.999), respectively. Conclusions- No difference in favorable outcome was seen between alteplase and control groups among patients with ischemic stroke with unknown time of onset. The safety of alteplase at 0.6 mg/kg was comparable to that of standard treatment. Early study termination precludes any definitive conclusions. Registration- URL: https://www.clinicaltrials.gov; Unique identifier: NCT02002325.

Trigeminal Neuralgia Due to Compression of Primitive Trigeminal Artery Variant: Usefulness of Fusion Images of Constructive Interference in Steady-State Magnetic Resonance Imaging and Computed Tomography Angiography.

BACKGROUND: Trigeminal neuralgia (TN) is one of the neuropathic pain syndromes, most commonly caused by vascular compression in the root entry zone of the trigeminal nerve in the cerebellopontine angle. It was rare as offending artery that primitive trigeminal artery and primitive trigeminal artery variant (PTAv) as an anomaly that occurs carotid-basilar anastomosis. We report a case of TN caused by the PTAv, and usefulness of fusion images of magnetic resonance imaging (MRI) and computed tomography angiography (CTA). CASE DESCRIPTION: A 65-year-old man presented with a 2-year history of left paroxysmal facial pain in the second division of the trigeminal nerve. We diagnosed left TN due to PTAv using constructive interference in steady state magnetic resonance imaging (CISS MRI) and CTA. Microvascular decompression surgery disclosed trigeminal nerve compressed by PTAv consisted with findings from preoperative neuroimaging. We report a case of TN caused by PTAv, and usefulness of fusion images of CISS MRI and CTA to understand the neurovascular and bony structure during the perioperative period. CONCLUSIONS: The fusion image created by CISS MRI and 3-dimensional CTA was useful to identify the offending vessel and to clearly understand the neurovascular structure preoperatively.

Delayed acute subdural hematoma treated with endoscopic procedure: A case report.

Background: Delayed acute subdural hematoma (DASDH) is defined as late onset ASDH with the absence of any abnormal radiological and clinical findings at initial examination. Moreover, this entity is very rare in traumatic brain injury and its mechanism is still unclear. Recently, endoscopic surgery for ASDH has also been performed. In this case, we describe some considerations of the mechanism of DASDH and review previous literature and usefulness of endoscopic surgical procedure for ASDH. Case Description: A 73-year-old man fell at night, and visited a former medical institution by himself. No abnormal neurological finding was detected. Head computed tomography (CT) detected no abnormal finding. He was diagnosed minor head injury and was hospitalized at midnight and discharged after brain magnetic resonance image (MRI) next day. Brain MRI also detected no abnormal findings. Three days later, he visited our hospital himself, because of the severe headache. Neurologically, he had a mild consciousness disturbance and head CT revealed left ASDH. We performed endoscopic evacuation of hematoma under local anesthesia. Then, the clot was evacuated under the endoscopic procedure through dilated burr hole and pulsatile bleeding from the cortical artery was observed, which was considered to be the source of the ASDH. The patient's consciousness disturbance was improved immediately after surgery and he discharged without neurological deficit. Conclusion: We revealed the source of bleeding of DASDH under endoscopic procedure and described hypothesis and speculation of its cause in our case. DASDH is rare entity, so we need further experiences and more considerations.

Novel Burr Hole Dilator for Endoscopic Surgery for Intracranial Hemorrhagic Lesion: Technical Note.

OBJECTIVE: When performing burr hole endoscopic neurosurgery, it is necessary to get enough surgical corridor. We have used various instruments to extend burr hole size, but it was cumbersome to use so many tools. METHODS: In this report, we describe a novel instrument-a dilator attachment with a cordless handle to make it simple and safe to extend a burr hole. We developed this burr hole dilator attachment with blades on the side and an arc form on the bottom to prevent dural damage. It can be used to drill safely and efficiently. We describe some experiences of using this device. RESULTS: It is important to balance the maximization of the operation range and surgical invasiveness for endoscopic neurosurgery. This new dilator for extending a burr hole is a safe, useful device to get enough surgical view and easily perform a surgical procedure in endoscopic surgery. CONCLUSIONS: Our dilator for expanding a burr hole improves the work of endoscopic surgery on intracranial hemorrhagic lesions.

[Magnetic Resonance Vessel Wall Imaging Reveals a Ruptured Blood Blister-like Aneurysm:A Case Report].

Recent advances in digital subtraction angiography(DSA)and 3D-CT angiography(3D-CTA)have enabled the identification of tiny intracranial aneurysms. However, the imaging of blood blister-like aneurysms(BBAs)in the internal carotid artery(ICA)is still challenging. We report the case of a subarachnoid hemorrhage(SAH)with a ruptured BBA in the ICA that was revealed by magnetic resonance vessel wall imaging(MR-VWI). A 68-year-old woman presented with SAH. CT showed diffuse SAH(Fisher group 3). 3D-CTA and DSA showed a small bulge in the right ICA. MR-VWI with gadolinium showed thick wall enhancement in the supraclinoid portion of the right ICA; hence, we diagnosed SAH because of the ruptured BBA of the right ICA. Trapping combined with high-flow bypass was performed for the ruptured BBA. We concluded that MR-VWI may be useful for diagnosing ruptured BBAs under strict blood pressure management.

Efficacy and Safety of REVIVE SE Thrombectomy Device for Acute Ischemic Stroke: River JAPAN (Reperfuse Ischemic Vessels with Endovascular Recanalization Device in Japan).

REVIVE SE (REVIVE) is a closed-ended, self-expanding stent retriever used in the RIVER JAPAN study. We present our early experience with REVIVE for revascularization of acute ischemic stroke (AIS) in patients who have failed or are ineligible for intravenous recombinant tissue plasminogen activator treatment. This prospective, single-arm, non-randomized, multicenter registry study followed up patients undergoing mechanical thrombectomy with REVIVE for 90 days. The primary endpoint was a post-procedure Thrombolysis in Cerebral Infarction (TICI) score ≥2a. Secondary endpoints were clot migration/embolization; recanalization without symptomatic intracranial hemorrhage (ICH) at 24 h; symptomatic ICH; good neurological outcome (modified Rankin Scale score ≤2 National Institute of Health Stroke Scale (NIHSS) score decrease ≥10) at day 90; device- or procedure-related serious adverse events (SAEs) and mortality at day 90. To confirm non-inferiority of REVIVE, results were compared with historical data of the Merci Retriever. About 49 patients were enrolled (median age 73 years; males 46.9%; middle cerebral artery (MCA) occlusion 83.7%; median NIHSS score 17). A post-procedure TICI score ≥2a was observed in 73.5% (36/49, 95% confidence interval [CI] 58.9-85.1) of patients. No post-procedural clot migration/embolization events occurred. Successful recanalization without symptomatic ICH was observed in 62.5% (30/48, 95% CI 47.4-76.0). The good neurological outcome was achieved in 66.7% (32/48) patients. Symptomatic ICH and device- or procedure-related SAEs were reported in 6.3% and 12.2% of patients, respectively. Two deaths were reported. REVIVE demonstrated equivalent efficacy and safety as the Merci Retriever. Results suggest that REVIVE is effective and safe in recanalizing occluded intracranial arteries in AIS.

[Magnetic resonance vessel wall imaging reveals rupture site in subarachnoid hemorrhage with multiple cerebral aneurysms].

We report a case of subarachnoid hemorrhage(SAH)with multiple cerebral aneurysms, in which magnetic resonance vessel wall imaging(MR-VWI)revealed the rupture site. A 68-year-old woman presented with SAH. Computed tomography(CT)showed diffuse SAH(Fisher group 3). 3D-CT angiography revealed two intracranial aneurysms:a 4.2-mm anterior communicating artery aneurysm(Acom An)and a 5.8-mm basilar tip aneurysm(BAtip An). As the BAtip An was the larger of the two, it was deemed the most likely site of rupture;however, high-resolution MR-VWI with gadolinium showed thick wall enhancement in the Acom An and no enhancement in the BAtip An. Thus, we performed a craniotomy for the Acom An. Intraoperative findings confirmed the rupture site at the Acom An. We concluded that high resolution MR-VWI may be useful for identifying the rupture site in patients with spontaneous SAH and multiple cerebral aneurysms.

[A case of calcified chronic subdural hematoma wherein MRI was useful for decision of the treatment strategy].

Calcified chronic subdural hematoma is a rare condition, representing 0.4-2.6% of all chronic subdural hematomas. It is often difficult to remove the hematoma without damaging the brain, owing to the adhesion between hematoma capsule and brain. Therefore, surgical intervention in managing calcified chronic subdural hematoma cases is still considered controversial. We report a case of calcified chronic subdural hematoma, which was successfully performed under microscopic guidance. A 72-year-old man complained of progressive left hemiparesis of 6-month duration. A CT scan revealed a calcified chronic subdural hematoma, 10 cm long and 4.5 cm thick, in the right convexity. On MRI, T2-weighted images showed a thin layer of cerebrospinal fluid intensity between the hematoma capsule and brain. There was no brain edema adjacent to the chronic subdural hematoma. Based on these MRI observations, we believed that adhesion between the hematoma capsule and brain would be mild. We then planned and succeeded in total removal of the calcified chronic subdural hematoma mass under microscopic guidance. The left hemiparesis disappeared after surgery. The patient was discharged without any neurological deficit. While considering surgical management in calcified chronic subdural hematoma cases, it should be important to evaluate adhesion between the hematoma capsule and brain with MRI.