Objective: Intracranial hemorrhage (ICH) after endovascular revascularization (ER) for acute ischemic stroke is associated with poor outcome. In this study, we examined the risk factors for postoperative ICH in patients who underwent ER in our hospital.

Methods: We investigated the incidence/type of postoperative ICH and risk factors in 157 patients who underwent ER in our hospital from July 2011 to June 2015.

Results: Postoperative ICH, including asymptomatic ICH, was observed in 57 (36.3%) patients. Symptomatic ICH occurred in seven patients (4.5%). According to the Safe Implementation of Thrombolysis in Stroke-Monitoring Study classification, hemorrhagic infarction type 2 and parenchymal hematoma type 2 were observed in 27 (47.4%) and 4 (7.0%) patients, respectively, of all patients with ICH. The frequency of patients with functional independence (score of 0–2 on the modified Rankin scale) 90 days after ER was significantly lower in patients with than without ICH (p <0.01). We performed a multivariate analysis of factors associated with postoperative ICH. The oral administration of anticoagulants prior to onset (p = 0.019; odds ratio [OR], 3.17; 95% confidence interval [CI], 1.22–8.54) and a prolonged onset-to-recanalization time (p = 0.043; OR, 1.11; 95% CI, 1.01–1.24) were associated with poor outcome.

Conclusion: ICH after ER may lead to an unfavorable outcome. Risk factors for ICH after ER included the oral administration of anticoagulants prior to onset and a prolonged onset-to-recanalization time.

Objective: A case in which intracranial arterial stenosis was exacerbated 5 months after percutaneous intracranial stent retriever thrombectomy is reported.

Case Presentation: In a 62-year-old male, percutaneous intracranial thrombectomy using a stent retriever was performed for acute occlusion of the basilar artery. After complete recanalization, a stenotic lesion considered to be atherosclerotic remained in the basilar artery, but the procedure was ended as there was no exacerbation. Although the patient was asymptomatic, cerebral angiography performed 5 months after the treatment showed progression of the remaining stenosis and poor delineation on the distal side of the stenosed area, and percutaneous transluminal angioplasty was carried out. Patency of the basilar artery was satisfactory on MRA 10 months after angioplasty.

Conclusion: Since existing atherosclerotic stenosis may be exacerbated after percutaneous intracranial thrombectomy using a stent retriever, follow-up of the treated vessel is necessary after this procedure.

Objective: A case that developed unilateral posterior reversible encephalopathy syndrome (PRES) after carotid artery stenting (CAS) is reported.

Case Presentation: The patient was a 79-year-old man who underwent CAS for symptomatic right internal carotid artery stenosis. Left hemiparesis and unilateral spatial neglect appeared on the day after the procedure. MRI presented findings characteristic of PRES although unilaterally. Temporary disruption of the blood–brain barrier due to blood pressure fluctuations in chronic unilateral hypoperfusion caused by stenosis of the right internal carotid artery or toxicity of the contrast medium was suspected.

Conclusion: PRES is considered to be a complication worth attention in CAS.

Objective: The number of access routes for endovascular treatment is limited in patients with a history of aorto-femoral bypass surgery. Here, we present a patient with stenosis of the coronary, left carotid, and innominate arteries. We performed simultaneous stenting of each stenotic lesion by direct puncture of a femoral artery graft with surgical exposure and purse string suture ligation.

Case Presentation: The patient was a 74-year-old male with a history of aorto-bifemoral bypass surgery, coronary artery stenting, and coronary artery bypass grafting for systemic atherosclerotic disease. Coronary artery stenting became necessary because of recurring angina pectoris. The three lesions were treated simultaneously by surgical exposure and direct graft puncture and 9 Fr sheath insertion. The punctured graft was sutured for hemostasis. No puncture site complications were noted.

Conclusion: This case suggests that when the number of possible access routes for endovascular treatment is limited, it is feasible and safe to perform direct graft puncture with surgical exposure, and to achieve hemostasis by suturing the puncture site.

Objective: We report a rare case of endovascular treatment for acute basilar artery occlusion (BAO) approached via the aberrant right subclavian artery (ARSA).

Case Presentation: A 66-year-old woman with atrial fibrillation was admitted for nausea and vomiting. She was progressively losing consciousness. At admission, her National Institutes of Health Stroke Scale (NIHSS) score was 38. Magnetic resonance angiography revealed BAO. An intravenous thrombolysis agent was administered at 2 hours and 20 minutes after symptom onset. Thrombectomy was performed using a stent retriever, resulting in complete recanalization at 4 hours and 39 minutes after symptom onset. While approaching the lesion, an ARSA was found. After the recanalization, her consciousness significantly improved, and her NIHSS score improved from 38 to 6 the day after the operation. She was discharged on day 17 with an NIHSS score of 1.

Conclusion: BAO is considered to have a poor prognosis. However, stent retriever thrombectomy may improve the prognosis of acute BAO. In addition, many anomalies such as ARSA can hinder the endovascular approach to intracranial arteries. Therefore, in-depth knowledge of vascular anatomy is necessary to perform this procedure.

Objective: Vertebral arteriovenous fistula (AVF) is rare in type 1 neurofibromatosis (NF1). We report a case of NF1 complicated by vertebral AVF, for which transarterial targeted embolization of the fistula resulted in a favorable outcome.

Case Presentation: A 44-year-old man with NF1 presented with cervical radiculopathy of the right fifth nerve root due to vertebral AVF. The fistula was completely occluded by transarterial targeted coil embolization of venous pouch of the fistula, and his neurological deficits got better. After a year follow-up, the fistula was completely occluded, and the patient's radiculopathy recovered almost completely.

Conclusion: Targeted embolization via artery can be the first-line treatment method for vertebral AVF associated with NF1.

Objective: A case in which an isolated sinus type dural arteriovenous fistula (AVF) that newly occurred in the transverse sinus after tumor resection by craniotomy was occluded by selective transvenous embolization (TVE) is reported.

Case Presentation: A 50-year-old woman had undergone resection of meningioma of the middle cranial fossa by craniotomy 50 months before. Tinnitus appeared 17 months after surgery, and exhaustive examination showed a dural AVF that appeared de novo in the transverse sinus occluded on the right sigmoid sinus side. The patient noted a heavy feeling of the head 50 months after surgery, and re-examination showed that the fistula became an isolated sinus type due to occlusion also on the confluence of sinus side with exacerbation of cortical venous reflux. After evaluation of the shunt point, the occluded areas were recanalized via the femoral vein by a quadriaxial catheter system using a 6 Fr guiding sheath, a 6 Fr guiding catheter, a 4.2 Fr catheter, and a microcatheter, and selective coil embolization was performed, resulting in disappearance of the shunt.

Conclusion: The occluded areas could be recanalized safely due to preoperative evaluation and the use of a quadriaxial catheter system and consequently, selective coil embolization became possible.

Objective: The first choice for the treatment of cavernous sinus dural arteriovenous fistula (CSdAVF) is transvenous embolization. The inferior petrosal sinus (IPS) approach is commonly used, but modification of the procedure is necessary in patients with IPS occlusion. We treated one patient by guiding a distal access catheter (DAC) to the cavernous sinus by the transfacial vein approach through the superior ophthalmic vein and obtained a favorable outcome.

Case Presentation: A 68-year-old woman with CSdAVF presented with ophthalmic symptoms. All feeding arteries converged in a pouch on the superior aspect of the medial posterior segment, and the superior ophthalmic vein/facial vein was the only drainage route. A 3.4 Fr TACTICS used as a DAC in a triple coaxial system was placed in the cavernous sinus via the facial and superior ophthalmic veins, a micro-catheter was navigated to the shunted pouch, and CSdAVF was embolized with two coils.

Conclusion: 3.4 Fr TACTICS is useful as a DAC in the transfacial vein approach to CSdAVF through the superior ophthalmic vein.

Objective: Although conservative treatment is the first choice for high cervical internal carotid artery (ICA) stenosis due to spontaneous cervical ICA dissection, surgical revascularization is necessary when the disease resists conservative treatment. Although such lesions are difficult to treat by conventional carotid endarterectomy (CEA) or carotid artery stenting (CAS), they may be treated less invasively by modified CAS with add-on devices. In this report, we present two cases of CAS performed by the combined use of balloon- and self-expanding stents with a review of the literature.

Case Presentations: Revascularization was performed by the same procedure in a 47-year-old man and a 43-year-old woman with left high cervical ICA stenosis. In the first case, no restenosis was noted on follow-up DSA performed after 1 year, but the self-expanding stent that initially overlapped the balloon-expandable stent had slipped off.

Conclusion: High cervical carotid artery stenosis due to spontaneous cervical ICA dissection can be treated by CAS using the proximal protection technique with the combined use of a balloon-expandable stent.