Objective: Carotid artery stenosis and cerebral aneurism may have different platelet functions and antiplatelet responses because these diseases have different etiologies. In this study, we compared the antiplatelet loading effects prior to endovascular treatment between carotid artery stenosis and unruptured cerebral aneurysm (UCA) patients.

Methods: Nine patients with asymptomatic carotid artery stenosis (ACS), 14 with symptomatic carotid artery stenosis (SCS), and 20 with unruptured cerebral aneurysms were enrolled in this study. Antiplatelet (aspirin + clopidogrel) loading effects prior to endovascular treatment were evaluated using light transmission aggregometry and platelet aggregate detection methods.

Results: Although there are differences in the prevalence of atherosclerosis risk factors, maximum aggregation rates in light transmission aggregometry and platelet aggregation-prone properties were not different in the three disease groups.

Conclusion: Preoperative dual antiplatelet therapy with aspirin and clopidogrel may be appropriate for both carotid artery stenosis and cerebral aneurism patients even though their conditions and background factors differ.

Objective: Pointwise encoding time reduction with radial acquisition (PETRA) using magnetic resonance angiography (MRA) is a non-enhanced MRA technique employing an ultrashort echo time, and is known to significantly reduce the magnetic susceptibility of coils and stents during post-embolization imaging. We evaluated the quality of PETRA-MRA images for use at the follow-up assessment of stent-assisted coil embolization procedures performed to treat aneurysms.

Methods: A total of six aneurysm patients who were treated by stent-assisted coil embolization were included. All patients underwent PETRA-MRA, time-of-flight (TOF)-MRA performed with MAGNETOM Skyra (Siemens), and digital subtraction angiography (DSA) performed with Infinix Celeve-i INFX-8000V (Canon Medical Systems) and Allura Clarity FD20/15 (Philips). The PETRA-MRA images were compared with those from DSA and TOF-MRA to validate the aneurysm occlusion status and visually assess the blood flow within the stent. Four independent specialists graded occlusion status and flow visualization through the stent using a four-point scale, where 4 points represented excellent visualization of flow within the stent.

Results: The aneurysm was located in the internal carotid artery in two patients, the middle cerebral artery in two patients, the top of the basilar artery in one patient, and the vertebral artery-posterior inferior cerebellar artery (VA-PICA) in one patient. Three patients were treated using a Neuroform Atlas Stent system, one using an Enterprise2 VRD, one using two Neuroform Atlas stents for Y-stenting, and the remaining patient using a Neuroform Atlas and an Enterprise2 VRD for Y-stenting. With DSA, the postoperative aneurysm occlusion status was neck remnant (NR) in five cases and complete obliteration (CO) in one case. DSA and PETRA-MRA evaluations demonstrated an equal occlusion status in five of six cases, whereas DSA and TOF-MRA were equal in two of six cases. The mean visualization score for PETRA-MRA was 3.33 ± 0.82, whereas that for TOF-MRA was 2.17 ± 1.33. On the PETRA-MRA images, blood flow through the stent was well-visualized and produced an aneurysm occlusion status score comparable to DSA, especially in the three cases using the Neuroform Atlas Stent System where the visualization was scored 4 points. In the case of the VA-PICA aneurysm, for which an Enterprise2 VRD was used, PETRA-MRA images were insufficient for postoperative assessment.

Conclusion: PETRA-MRA can provide good visualization of the blood flow within a stent and displays a clear blood signal near the coils, barring small magnetic susceptibility artifacts. Therefore, PETRA-MRA may be an effective option for follow-up imaging after stent-assisted coil embolization.

Objective: We report a case of anterior condylar confluence dural arteriovenous fistula (ACC dAVF) in whom venous reflux presentation was converted to the anterior medullary vein (AMV) during the observation period.

Case Presentation: A 63-year-old woman with ACC dAVF, which only had anterograde drainage routes, exhibited dizziness during the observation period. Magnetic resonance imaging (MRI) revealed an abnormal hyper-intense area in the pons to the medulla. We performed cerebral angiography and reflux to the AMV was found. As the other drainage route using the internal jugular vein (IJV) remained, transvenous embolization (TVE) was performed to treat this ACC dAVF. No neurological deficits were observed and hyper-intensity in the brain stem disappeared after treatment.

Conclusion: Although such cases are markedly rare, it is necessary to keep in mind that ACC dAVF may convert to the venous reflux presentation to the AMV during the natural course.

Objective: We report a case of the marked growth and rupture of a giant femoral artery pseudoaneurysm at the puncture site that developed after recanalization therapy for acute basilar artery occlusion

Case Presentation: A 79-year-old woman developed acute ischemic stroke due to atherosclerotic basilar artery occlusion. Endovascular intervention was performed and recanalization of the affected vessel was achieved. However, she developed brainstem infarction and consciousness disturbance persisted. The femoral access site was treated using a vascular closure device at the end of the procedure. A right femoral artery pseudoaneurysm of approximately 5 cm in size was found 2 weeks after onset during the examination for deep venous thrombosis with right lower extremity edema. Manual compression did not achieve thrombotic occlusion of the aneurysm due to obesity and leg edema. Considering the severe neurological status of the patient, the pseudoaneurysm was followed up without surgical treatment. Dual antiplatelet therapy and direct oral anticoagulant agents were administered. Four weeks after onset, the pseudoaneurysm presented rapid growth, and on the 35th day after onset, it exceeded 15 cm in size and ruptured, causing hemorrhagic shock with massive femoral hematoma. Pseudoaneurysm resection and hematoma removal were performed surgically, and the patient recovered. However, improvement of neurological manifestations was poor and the modified Rankin Scale at 90 days after onset was 5.

Conclusion: A case of giant femoral artery pseudoaneurysm following recanalization therapy for acute ischemic stroke was reported. Pseudoaneurysms at the puncture site can rupture after significant growth. Curative treatment is required without delay.

Objective: Stanford type A acute aortic dissection (AAD) is associated with carotid artery dissections (CADs). We report two cases of carotid artery stenting (CAS) for symptomatic CAD after ascending aortic replacement (AAR) for AAD.

Case Presentation: Case 1: A 51-year-old man with AAD was transferred to our institute. He had no notable paralysis symptoms on initial presentation. However, after AAR for AAD was performed, left paralysis developed within a few hours. Emergency angiography revealed right CAD and pseudo-occlusion. CAS was performed successfully using intravascular ultrasound (IVUS). He was transferred to a rehabilitation hospital with a modified Rankin Scale (mRS) score of 2.

Case 2: A 55-year-old man underwent AAR for AAD, but asymptomatic left CAD remained. Two weeks after the operation, he presented with slight signs of aphasia. Aspirin was prescribed and follow-up was performed, but his symptoms did not improve. He underwent magnetic resonance imaging in our department, which revealed acute cerebral infarction on the left pars opercularis and an artery-to-artery embolism from CAD. CAS was performed via the retrograde approach with direct puncture of the normal left common carotid artery using IVUS. He was discharged with no complications and a mRS score of 1.

Conclusion: IVUS can be useful for CAS to confirm the true lumen and extension of long CAD lesions developing from AAD.

Objective: We report two cases of dural arteriovenous fistula (DAVF) treated by coil embolization of the affected sinus and fistula via a feeding artery instead of transvenous embolization (TVE) due to the difficulty of the transvenous approach.

Case Presentation: An 82-year-old man was diagnosed with transverse sinus (TS) DAVF. A microcatheter was inserted into the isolated TS through the fistula via the middle meningeal artery (MMA), which was the feeding artery of the DAVF. The DAVF was occluded by coil embolization of the isolated sinus and fistula. A 79-year-old man was diagnosed with cavernous sinus (CS) DAVF. A microcatheter was inserted into the CS through the fistula via an accessory meningeal artery (AMA), which was the feeding artery of the DAVF. The DAVF was occluded by coil embolization of the affected sinus and fistula.

Conclusion: These cases suggested that transarterial sinus coiling is one of the effective treatment options for DAVF.

Objective: This report presents a case of mechanical thrombectomy for left internal carotid artery (ICA) terminal portion occlusion performed by left common carotid artery recanalization during hospitalization after diagnosing bilateral common carotid artery occlusion due to Takayasu arteritis.

Case Presentation: A 25-year-old woman with fever and cervix pain a few months ago visited our department after repeated transient aphasic attacks. Magnetic resonance imaging (MRI) demonstrated diffuse infarction in the left middle cerebral artery (MCA) area, and she was diagnosed with Takayasu arteritis due to bilateral common carotid artery occlusion and left subclavian artery stenosis. On the 20th day of hospitalization, the terminal portion of the left ICA was occluded and thrombectomy was performed after balloon dilation of the left common carotid artery. Lastly, left common carotid artery stenting was performed. Aphasia and sensory disturbance remained, but she was transferred to a rehabilitation hospital with a modified Rankin Scale (mRS) of 2 on the 65th day of hospitalization. Antithrombotic and immunosuppressive therapy were performed, and restenosis did not develop.

Conclusion: Angioplasty and stenting of common carotid artery occlusion can be effective treatments in thrombectomy for intracranial occlusion due to Takayasu disease.

Objective: We report a case of a wide-necked internal carotid-posterior communicating (IC-Pcom) artery aneurysm treated by the retrograde T-stent technique in which a stent was also placed in the Pcom artery via the posterior circulation.

Case Presentation: A 35-year-old woman was diagnosed with an unruptured right IC-Pcom artery aneurysm (maximum diameter: 11 mm, neck diameter: 8.5 mm) during a detailed examination for vertigo. The Pcom artery (2.1 mm) branched from the aneurysmal dome. A microcatheter was guided in retrograde via the Pcom artery from the posterior circulation. A low-profile visualized intraluminal support (LVIS) Jr. 2.5 mm × 17 mm was deployed from the internal carotid artery (ICA) to the Pcom artery, and then, an LVIS 4.5 mm × 23 mm was deployed while pressing the flare of the LVIS Jr. protruding into the ICA. T configuration stenting was completed, and the coil was inserted as tightly as possible.

Conclusion: The retrograde T-stent technique, which has the advantage of optimal stent positioning, is useful for preserving a Pcom artery branching from the aneurysmal dome.

Objective: We report a simplified method of manual transfusion with a one-way valve during carotid artery stenting (CAS) with flow reversal.

Case Presentation: A 77-year-old man with cervical internal carotid artery stenosis who developed vulnerable plaques was scheduled for CAS using flow reversal. Blood flow reversal was naturally caused by the arteriovenous pressure gradient, and a method with a one-way valve, which enables simplified manual transfusion using a syringe technique, was used for the patient. CAS was completed without distal embolization.

Conclusion: Manual transfusion can be simplified using a one-way valve in cases of flow reversal during CAS, which often require complicated procedures.

Objective: We report a case of mechanical thrombectomy (MT) via the distal transradial approach (dTRA) and technical tips.

Case Presentation: An 89-year-old woman was transferred to our hospital due to back pain after a fall and sudden-onset left hemiparesis. We performed MT because three-dimensional computed tomography angiography (3D-CTA) revealed right middle cerebral artery (MCA) occlusion. The access route was Type 3 aortic arch. The abdominal aorta and common iliac artery were tortuous and partially dissected, and she had a lumbar vertebra fracture. We selected dTRA in consideration of safety, ease of access, and less postoperative postural restriction. The first pass resulted in complete recanalization using an aspiration catheter and stent retriever. Her symptoms rapidly improved and she was discharged with a modified Rankin Scale score of 1.

Conclusion: dTRA in MT may be a treatment option.