Intracranial vertebral artery (ICVA) refers to the intracranial segment of the vertebral artery which is usually involved with atherosclerosis and dissection. Considering the high incidence and severe consequence of occlusive artery disease in this location, little attention has been paid to the chronic total occlusion (CTO) of ICVA and the corresponding endovascular treatment (EVT). In this mini review, ICVA CTO is discussed based on the definition, incidence, clinical manifestation, endovascular recanalization treatment, complications, and outcomes.

Objective: The optimal heating temperature and time for the Echelon10 and Excelsior SL-10 microcatheters using a heat gun was investigated. The durability of the microcatheters after heat gun shaping for the second and third times was also examined.

Methods: HAKKO FV-310 was used as the heat gun in this study. This heat gun can be set to 115°C, 125°C, and others. We measured the temperature at 2.5 cm from the nozzle of the heat gun. The Echelon10 and SL-10 microcatheters were shaped under two temperature conditions (115°C and 125°C) and three heating times (30 sec, 60 sec, and 90 sec). The microcatheter shape before heating had twice the curvature of the targeted shape.

Results: The temperatures at 2.5 cm from the nozzle were 120.6°C and 127.8°C with the heat gun set at 115°C and 125°C, respectively. There was no macroscopic difference in the results of heat gun shaping of the Echelon10 among temperature settings (115°C and 125°C) or heating times (30 sec, 60 sec, and 90 sec). As degeneration of the heated tip of the SL-10 at 125°C occurred in four of five trials, heat gun shaping was performed using the 115°C setting. There was no macroscopic difference in the results of heat gun shaping of the SL-10 among heating times. Shaping for the second and third times was successful at 115°C and 30-sec heating time.

Conclusions: The Echelon10 and SL-10 can be successfully shaped from twice the curvature of the targeted shape using a heat gun at 120°C for 30 sec. Shaping for the second and third times was successful using the same settings. Degeneration of the SL-10 was noted at temperatures above 130°C.

Objective: In neuroendovascular therapy, clopidogrel resistance and thrombosis are common problems. In such cases, we use prasugrel as rescue medication, and we clarified its usefulness.

Methods: We retrospectively investigated 199 consecutive cases of neuroendovascular therapy performed at our hospital from April 2016 to March 2018, and examined the safety and effectiveness of prasugrel.

Results: There were 14 cases of prasugrel administration: six cases of coil embolization for cerebral aneurysm, five cases of carotid artery stenting (CAS), and three other cases.

The reasons for prasugrel administration were as follows: emergency stent use in four cases, intraoperative thrombosis in three cases, intra-stent thrombosis after CAS in three cases, and others in four cases. In all cases, it was used in combination with aspirin and the median duration of administration was 212 days. Regarding its safety, there was one hemorrhagic complication at the puncture site for which the involvement of prasugrel was unable to be excluded, but it was improved by conservative treatment and there was no major hemorrhage such as intracranial hemorrhage. Regarding its efficacy, in one case, the thrombus during coil embolization did not completely disappear after prasugrel administration and additional mechanical thrombolysis was required. However, no new thrombosis was observed during prasugrel administration in all 14 cases.

Conclusion: Prasugrel may be useful as a rescue medication in neuroendovascular therapy.

Objective: Dissecting aneurysms of the anterior choroidal artery (AchoA) are extremely rare, with only a few reported cases. Herein, we report an extremely rare case of subarachnoid hemorrhage with dissecting aneurysm of the AchoA.

Case Presentation: A 68-year-old man was hospitalized for sudden onset of headache, progressive consciousness disorder, and right hemiparesis. He had a prior medical history of systemic lupus erythematosus (SLE), and was taking prednisolone (50 mg/day) for 15 months. CT showed subarachnoid hemorrhage in the left side of the basal cistern and Sylvian fissure. Left internal carotid artery (ICA) angiography revealed a fusiform aneurysm of the AchoA. He was diagnosed with a ruptured dissecting aneurysm of the AchoA because the shape of aneurysm was fusiform and there was laminar flow inside the aneurysm. Parent artery occlusion (PAO) was performed to prevent re-hemorrhage on the day of onset. Although ventricular drainage for acute hydrocephalus was performed after AchoA occlusion, his consciousness disorder did not improve. Postoperative angiography at 1-week recovery from the procedure revealed disappearance of the AchoA, including the dissecting aneurysm. However, he died following septic shock caused by pneumonia at 1 month after the procedure.

Conclusion: We report an extremely rare case of subarachnoid hemorrhage with a dissecting aneurysm of the AchoA. Vasculitis caused by SLE and a vulnerability of the vessel wall following chronic steroid use are potential causes of the dissecting aneurysm of the AchoA.

Objective: We report a case in which multiple overlapping low-profile visualized intraluminal support (LVIS) stents were used as monotherapy for ruptured blood blister-like aneurysm (BBA) of the internal carotid artery (ICA).

Case Presentation: A 48-year-old female presented to the emergency room with acute-onset headache. She was alert without neurological deficit with subarachnoid hemorrhage (SAH) Hunt and Kosnik grade I. Emergency angiography revealed a BBA from the supraclinoid ICA. This aneurysm had a small diameter, which makes coil embolization difficult. Therefore, we planned to use multiple overlapping LVIS stents as monotherapy for the ruptured aneurysm. The postoperative course was uneventful without rebleeding. The patient exhibited no neurological deficits on the clinical follow-up at 1 year.

Conclusion: Multiple overlapping LVIS stents as monotherapy is useful for ruptured BBAs of the ICA.

Objective: We experienced a case of difficult catheterization to the left brachiocephalic vein (LBCV) during transfemoral transvenous embolization for traumatic carotid-cavernous fistula. We discussed the cause of this phenomenon.

Case Presentation: A 78-year-old woman with a traumatic carotid-cavernous fistula was treated with combined transarterial and transvenous embolization; however, catheterization to the LBCV was very difficult. A balloon guiding catheter (BGC) already placed in the left common carotid artery (LCCA) caused displacement of the LCCA and further compression of the originally stenotic LBCV.

A CT investigation of 104 cases of neuroendovascular treatment in our hospital revealed that the distance between the ventral bones and the dorsal arteries sandwiching the LBCV was significantly negatively correlated with age (r = −0.41, p = 0.000020). Aging and arteriosclerotic change are possibly related to the LBCV stenosis.

Conclusion: When catheterization to the LBCV is difficult during transfemoral transvenous embolization, not only the presence of anatomical variations and stenosis or occlusion of LBCV itself but also compression from surrounding structures should be considered, especially in elderly patients. In rare cases, a catheter inserted in an adjacent artery may cause further compression of the LBCV.

Objective: For curative Onyx embolization of dural arteriovenous fistulas (dAVF) with multiple feeders, it is essential to select the optimal target artery as well as to control the blood flow at the fistula point. We report a case of tentorial dAVF (TdAVF) treated by Onyx embolization under flow control using balloon catheters.

Case Presentation: A 66-year-old male was admitted to our hospital for treatment of TdAVF detected incidentally by MRI, which revealed a dilated and tortuous vein around the cerebellum. Cerebral angiography demonstrated a TdAVF, fed mainly by bilateral middle meningeal arteries (MMA) and bilateral occipital arteries (OA), with the fistula point at the torcular and venous drainage to the two superior vermian veins (SVVs). Onyx 18 was injected from the low-flow feeder of the MMA under flow control by occluding the high-flow feeder of the OA using balloon catheters, obliterating the arteriovenous shunt.

Conclusion: In treatment of TdAVF involving low- and high-flow feeders, Onyx embolization via the low-flow feeder with temporary balloon occlusion of other high-flow feeders is a useful method. This technique makes it easier for Onyx to penetrate the fistula point.