Objective: The effects of difference in the guiding system on the results of stent thrombectomy were investigated.

Methods: Of the patients who underwent intracranial thrombectomy using a stent retriever in 2015 and 2016, those with lesions in the internal carotid artery (ICA) or the horizontal (M1) segment of the middle cerebral artery were divided into a group treated with a balloon guide catheter (BGC) alone and a group treated with a combination of BGC + distal access (aspiration) catheter (DAC), and 1) the time from puncture to recanalization, 2) number of passes, 3) frequency of occurrence of embolization to new/distal territory (ENT/EDT), and 4) percentage of complete recanalization were compared.

Results: The subjects were 17 patients consisting of 6 in the BGC group and 11 in the BGC + DAC group. The results concerning the above items were 1) 80.0 vs. 46.7 min (p = 0.03), 2) 2.8 vs. 1.5 times (p = 0.03), 3) 50% vs. 0% (p = 0.03), and 4) 66.7% vs. 90.9% (p = 0.52), respectively.

Conclusion: In the BGC + DAC group, the time until recanalization was shorter, the number of passes was fewer, and the frequency of ENT/EDT was lower, suggesting that more favorable results may be obtained by BGC + DAC.

Objective: There are concerns regarding ischemic events associated with stent-assisted coil embolization. It is important to evaluate the risk factors for delayed thromboembolic events. This study evaluated risk factors after reduction to single-antiplatelet therapy 140–365 days after embolization.

Methods: We conducted a retrospective and cross-sectional study of patients who underwent stent-assisted coil embolization. Sixty eight aneurysms in 67 patients with unruptured intracranial aneurysms or the chronic phase of ruptured intracranial aneurysms between July 2010 and April 2014 were evaluated.

Results: Dual-antiplatelet therapy was administered for 157 ± 65 days. Three patients who were administered the single-antiplatelet agent experienced postoperative ischemic events. One patient experienced cerebral infarction 143 days after the procedure. One patient with over 50% in-stent stenosis experienced cerebral infarction 194 days after the procedure. The final patient experienced transient ischemic attack (TIA) 223 days after the procedure, and re-embolization was performed 209 days after the procedure. Postoperative ischemic events occurred more frequently in severe in-stent stenosis patient (P <0.05).

Conclusions: However, severe in-stent stenosis may be a risk factor after reduction to single-antiplatelet therapy, relatively few ischemic events occurred after cessation of dual-antiplatelet therapy.

Objective: N-butyl cyanoacrylate (NBCA) is used as a liquid embolic agent in various hemorrhagic situations with a high technical success rate and low recurrent bleeding rate, especially in patients with coagulopathy.

Case Presentation: An adult patient was admitted to the intensive care unit with coagulopathy and hemorrhagic shock. Past medical history of the patient included dual-antiplatelet therapy and warfarinization for several cardiac diseases. Retroperitoneal hematoma caused by femoral artery (FA) branch injury following percutaneous FA puncture was determined. Thus, we performed endovascular therapy (EVT) using NBCA and achieved successful hemostasis.

Conclusion: NBCA used for hemostasis is linked to good technical success and the absence of complications. We concluded that EVT using NBCA is safe and effective among patients with iatrogenic FA branch injury following neuro endovascular therapy as adjunct for other conventional embolic agents.

Objective: We encountered a patient with lateral medullary infarction during transarterial embolization of the posterior meningeal artery (PMA). We reviewed the anatomic characteristics/imaging findings of this disorder.

Case Presentation: A 69-year-old male. Cerebral infarction involving the lateral medulla occurred during transarterial embolization of a dural arteriovenous fistula. It was considered to be a complication related to occlusion of a lateral medulla-penetrating vessel on microcatheter/guidewire operations in the PMA. When examining images in detail, the blood vessel could be confirmed using DSA and 3D angiography.

Conclusion: When performing embolization, the presence of a brainstem-penetrating vessel originating from the PMA must be considered.

Objective: We report a case of herpes encephalitis that occurred after coil embolization of cerebral aneurysm.

Case Presentation: A 66-year-old woman underwent stent-assisted coil embolization for the recurrence of basilar tip aneurysm. She was discharged to home but noted fever 30 days after the procedure, and as she developed disorientation and disturbance of consciousness, she consulted the outpatient clinic of our hospital. MRI showed abnormal signals mainly in the mesial right temporal lobe, and with a diagnosis of herpes encephalitis based on the cerebrospinal fluid (CSF) tap test, acyclovir drip infusion was performed. While disturbance of consciousness was resolved, disorientation and short-term memory loss persisted.

Conclusion: There is a possibility that herpes encephalitis was induced by the intracranial endovascular procedure. Herpes encephalitis should be recognized as a possible complication after intracranial endovascular therapy.

Objective: Six cases in which carotid artery stenting (CAS) was performed using a distal embolic protection device (EPD) for distal internal carotid artery (ICA) stenosis near the carotid canal are reported.

Case Presentations: Of the 504 consecutive cases of ICA stenosis endovascularly treated at our hospital between April 1, 2008 and December 31, 2016, six cases with lesions in the distal potion of the cervical ICA near the carotid canal underwent CAS using Carotid Guardwire PS. The six patients were all males aged 68–80 years (median: 78.5 years), and three patients were symptomatic. The mean percent stenosis was 91% (80%–96%) preoperatively and 10.3% (0%–27%) postoperatively. In five patients, gross debris was detected in the blood aspirated during the procedure. In the patient with 27% residual stenosis, calcified plaque was confirmed at the entry of the carotid canal on postoperative CTA. No stroke, myocardial infarction, or death was noted within 30 days after the perioperative period, but a new ischemic lesion was detected in one patient on diffusion-weighted MRI. The mean follow-up period in the six patients was 28 months (7–66 months), and ipsilateral stroke or restenosis was not observed.

Conclusion: CAS using EPD is considered an effective option for the treatment of distal ICA stenosis near the carotid canal.

Objective: We report a patient who underwent staged angioplasty (SAP) for stenosis of the cervical internal carotid artery (ICA), but developed hyperperfusion syndrome.

Case Presentation: The patient was an 84-year-old male. Stenosis of the left cervical ICA (pseudo-occlusion) related to cerebral infarction was observed. Emergency angioplasty was performed. At 9 days after the procedure, carotid artery stenting (CAS) was conducted. Restlessness was noted immediately after CAS. In addition, right hemiparesis and aphasia were exacerbated, and a convulsive seizure occurred 4 days later. MRI did not reveal the new onset of cerebral infraction. Single-photon emission computed tomography (SPECT) showed an increase in cerebral blood flow (CBF) in the left parietal lobe, leading to a diagnosis of hyperperfusion syndrome. An anticonvulsive drug was administered, and strict blood pressure control was performed. There was no hemorrhagic complication. The patient was referred to a rehabilitation hospital.

Conclusion: The present case developed hyperperfusion syndrome despite SAP was performed. Currently, there is no consensus for the interval; it is important to carefully determine the interval in each patient by evaluating cerebral perfusion status.

Objective: Case reports in regard of using Pipeline Embolization Devices (PED): endoluminal reconstruction device for treatment of iatrogenic internal carotid artery (ICA) injury is still rare. We describe a successfully treated case of surgical iatrogenic ICA injury by double overlapped PEDs placement.

Case Presentation: A 79-year-old female underwent endoscopic trans-nasal aspiration for chronic sphenoid and ethmoid sinusitis. This surgery was complicated by brisk arterial bleeding developed along the right lateral wall in the sphenoid sinus. There was a concern that the bleed could related to a tear in the cavernous segment of the right ICA. Immediate angiogram showed a small pseudo-aneurysm appearance, corresponding with the injured site. The pseudo-aneurysm spontaneously disappeared, however, owing to recurrence of arterial nasal bleeding of upon nasal packing removal, double overlapped PEDs were successfully placed in the right ICA cavernous/supraclinoid segment. Immediate cessation of bleeding was achieved and packing could be removed.

Conclusion: The use of PED for surgical iatrogenic ICA injury appears to be a rational therapeutic alternative with preservation of the parent artery blood flow.