Objective: We retrospectively reviewed patients who had undergone preoperative embolization of cerebellar hemangioblastomas with a liquid embolic material, n-butyl-2-cyanoacrylate (NBCA), by the plug and push technique.

Methods: The subjects were six patients who had undergone preoperative embolization of cerebellar hemangioblastomas in our hospital between April 2016 and October 2017. In all patients, a microcatheter was selectively guided into a feeder, and tumor embolization with low-concentration NBCA, which had been diluted with oily contrast medium, was performed using the plug and push technique before tumor resection based on approval by the Ethics Review Board of our hospital.

Results: The male-to-female ratio was 5:1. The mean age was 33.8 ± 10.7 years. The tumor type was evaluated as nodular in three patients and solid in three patients. The mean nodular size was 26 ± 8.9 mm. The mean interval from embolization until surgery was 1.3 days (1–4 days). In all patients, the procedure could be accomplished. The mean concentration of NBCA was 19.4% ± 1.4%. Concerning the embolization effects, cerebral angiography showed complete occlusion in four patients and partial occlusion in two patients. There was no embolization-related complication or adverse event. Under suboccipital craniotomy, total tumor resection was possible in five patients, whereas one patient required blood transfusion.

Conclusion: Preoperative embolization of cerebellar hemangioblastomas with low-concentration NBCA by the plug and push technique may be useful for accomplishing tumor resection although catheter adhesion on infusion must be considered.

Objective: In endovascular thrombectomy for acute ischemic stroke due to large-vessel occlusion, occluded vessels are invisible on MRA or DSA. Heavily T2-weighted MRI sequence, which offers good contrast between cerebrospinal fluid and other brain structures, may contribute to resolve this issue. This study aimed to evaluate the efficacy of this sequence in estimating vessel courses including unexpected aneurysms of the portion more distal to the occlusion site in endovascular thrombectomy.

Methods: In all, 23 consecutive patients diagnosed with acute ischemic stroke due to large-vessel occlusion underwent endovascular thrombectomy subsequent to evaluation of several thin-slice coronal sections of heavily T2-weighted MRI in addition to the usual diagnostic MRI. To clarify the usefulness of the heavily T2-weighted MRI, the matching degree of vessel courses diagnosed using this sequence before and after recanalization, intra- or postoperative subarachnoid hemorrhage, reperfusion rate of thrombolysis in cerebral infarction (TICI) 2b-3, and the rate of functional independence (modified Rankin Scale [mRS] score ≤ 2) at 90 days were assessed. And also the following time intervals were calculated: start of imaging to arterial puncture, arterial puncture to first deployment of device, and arterial puncture to reperfusion.

Results: The site of occlusion at diagnosis was the internal cerebral artery (ICA) in eight patients, the middle cerebral artery (MCA) in 13, and the anterior cerebral artery and basilar artery in 1 each. The matching of vessel courses before and after treatment was observed in 20 patients (91.3%) except for two patients that useful images could not be provided because of intense body movement and a technical failure. Procedure-related subarachnoid hemorrhage was not recognized in any patient. Successful recanalization of TICI 2b-3 was achieved in 82.6%. The median time from start of imaging to arterial puncture was 51 minutes (interquartile range [IQR]: 38.75–72), arterial puncture to first deployment of device was 41 minutes (32–57), placement of a guiding catheter or completion of carotid stenting to first deployment of device was 20 minutes (13.75–28.5), and arterial puncture to reperfusion was 59 minutes (43.5–99.5), respectively. Functional independence (mRS ≤2) at 90 days was achieved in 43.5% of patients. Heavily T2-weighted MRI was extremely useful in facilitating secure navigation of a microguidewire and microcatheter into invisible vessels during thrombectomy by confirming the courses of occluded vessels in advance. On the other hand, this sequence neither delayed the time to arterial puncture remarkably nor reduced the time required for procedure by estimating of occluded vessels.

Conclusion: The heavily T2-weighted MRI sequence can contribute to improve the safety of maneuvers by clarifying the course of occluded vessels in endovascular thrombectomy for large-vessel occlusion.

Objective: We report a case involving a patient in whom endovascular treatment for bilateral bacterial cervical aneurysms led to a favorable outcome.

Case Presentation: A 67-year-old male was diagnosed with bilateral bacterial cervical aneurysms during treatment for infectious endocarditis, and was referred to our hospital. Contrast-enhanced CT revealed aneurysms around the bifurcations of the bilateral carotid arteries. Antibiotic administration did not reduce the aneurysms, and endovascular treatment was performed. Stenting was conducted in the bilateral carotid arteries, and there was a marked reduction in the right aneurysm size. However, the left aneurysm was only transiently reduced and reappeared. Coil embolization was performed, leading to the disappearance of the left aneurysm.

Conclusion: Endovascular treatment may be an option for bacterial cervical aneurysms.

Objective: We report a case of sudden bilateral sensorineural hearing loss caused by atherosclerotic occlusion of vertebral artery which improved after angioplasty with stenting.

Case Presentation: The patient was a 71-year-old male. He was referred to our hospital from an otolaryngologist with severe, rapidly progressing hearing loss and vertigo. Cerebral angiography revealed occlusion of the predominant left vertebral artery, suggesting ischemia in the bilateral anterior inferior cerebellar artery (AICA) territories. Urgent balloon angioplasty was performed but after additional angioplasty, acute vessel reocclusion occurred associated with intimal dissection. Rescue stenting was performed and led to recanalization. After treatment, his hearing disturbance rapidly improved.

Conclusion: Cochlear disorder caused by ischemia in the bilateral AICA regions may induce severe acute bilateral hearing loss. Acute revascularization is useful, but it is necessary to prepare stents for angioplasty and carefully evaluate whether treatment is indicated.

Objective: We report a patient in whom antegrade blood flow blockage with a balloon guiding catheter was effective for external iliac artery (EIA) rupture on 9 Fr sheath insertion.

Case Presentation: Thrombectomy was selected for a 76-year-old male in the acute phase of cerebral infarction. The right common femoral artery (CFA) was punctured, and a 4 Fr sheath was exchanged for a 9 Fr sheath. At this point, EIA rupture occurred, causing shock. Hemostasis was not achieved by manual compression. The contralateral CFA was punctured, and a 9 Fr OPTIMO (Tokai Medical Products, Aichi, Japan) was guided to proximal side of the point of rupture. His blood pressure was stabilized by blocking antegrade blood flow via balloon inflation. Artificial blood vessel replacement was performed, leading to a favorable outcome.

Conclusion: Antegrade blood flow blockage with a balloon was effective for EIA rupture.

Objective: We report a case of internal carotid artery (ICA) dissection presenting acute intracranial occlusion and accompanied with simultaneous carotid cavernous fistula (CCF) treated by thrombectomy.

Case Presentation: The patient was a 43-year-old male who presented with severe neurological symptoms. Imaging findings demonstrated acute ischemic stroke with occlusion of the left ICA. A retrospective review of angiogram showed ICA dissection-related occlusion with a fine CCF. However, dissection could not be recognized initially, and thrombus aspiration with Penumbra system was performed as revascularization therapy. Recanalization of the ICA was not achieved and the CCF deteriorated. Considering the risk of hemorrhagic complications and the treatment of CCF, parent artery occlusion of the ICA was conducted. The CCF disappeared; however, an extensive area of the left middle cerebral artery territory was infarcted.

Conclusion: In revascularization for acute ischemic stroke, it is important to adequately evaluate the condition such as dissection and to select an appropriate therapeutic strategy.

Objective: A case that suffered vessel perforation during flow diverter stent placement is reported.

Case Presentation: The patient was a 65-year-old woman with an unruptured aneurysm 10 mm in maximum diameter at the paraclinoid portion of the left internal carotid artery. She developed disturbance of consciousness a few hours after elective flow diverter stent placement, and diffuse subarachnoid hemorrhage was noted on head CT. Although rupture of aneurysm was suspected, bleeding from the left angular artery was confirmed by emergent angiography. Trapping of the same site was carried out. Vessel perforation due to jump-up of the delivery wire was retrospectively estimated to be the cause of bleeding.

Conclusion: Vessel perforation is a serious complication of intracranial endovascular treatment, and its cause and treatment are discussed with a review of the literature.

Objective: We report two patients for whom the proximal balloon protection (PBP) method was used during transradial carotid artery stenting (TR-CAS).

Case Presentations: Case 1 was a 79-year-old male. TR-CAS for acute occlusion of the internal carotid artery was performed. A 6 Fr balloon guiding catheter was introduced into a 6 Fr guiding sheath, and CAS was conducted by passing through the lesion under PBP. Case 2 was an 83-year-old male. TR-CAS was performed to treat marked stenosis of the internal carotid artery. It was difficult to pass the catheter through the lesion, but PBP with a balloon guiding catheter enhanced the supporting power, facilitating lesion passage, and CAS was successful.

Conclusion: No study has reported PBP during TR-CAS, but we were able to perform PBP during TR-CAS by adopting this method, and the support for lesion passage may be enhanced. This method may be useful for patients at risk of distal embolism or for those in whom lesion passage is difficult.