Objective: The association between stent design and post-stent intravascular findings after carotid artery stenting (CAS) was evaluated.

Methods: Among the 79 patients who underwent CAS between March 2016 and June 2020 at our institution, we retrospectively analyzed 65 patients with full post-stent intravascular evaluation by both optical frequency domain imaging and angioscopy. All CAS procedures were performed under the flow reversal method, and the stent selection was determined by each operator’s discretion, depending on the vessel anatomy or plaque characteristics. The patient’s characteristics, plaque characteristics, ischemic complication, and post-stent intravascular findings (plaque protrusion, vessel wall apposition of stent) were compared between the closed-cell and open-cell stent groups.

Results: The closed-cell group (n = 34) had more high-risk plaques, such as symptomatic lesions or intraplaque hemorrhages, on MRI compared with the open-cell group (n = 31). There was no difference in the rate of ischemic complications between the groups. Although there was no difference in the frequency of plaque protrusion between the two, the maximum height of the protruded plaque was higher in the open-cell group (320 vs. 612 μm, p = 0.003) and incomplete apposition was higher in the closed-cell group (85.3 vs. 6.5%, p <0.0001).

Conclusion: The open-cell stent provided better apposition but had larger plaque protrusion. The need for a new hybrid stent that combines the merits of both open- and closed-cell stents was suggested.

Objective: Coil embolization for the treatment of internal carotid artery–posterior communicating artery aneurysms (PComAAn) associated with oculomotor nerve palsy (ONP) remains controversial in terms of the therapeutic effect to improve ONP. Patients with PComAAn treated in our hospital were retrospectively analyzed to evaluate the effectiveness of coil embolization on ONP.

Methods: Twenty-three patients who had coil embolization for PComAAn with ONP were included in the analysis. In the evaluation of postoperative outcome of ONP, complete resolution of all symptoms was considered as a total recovery. ONP with a few residual symptoms that are stable and not disabling was considered as a subtotal recovery and that with only a slight improvement as a partial recovery.

Results: Preoperative ONP was complete palsy in 14 and partial palsy in nine cases. The mean maximum diameter of the aneurysms was 9.1 ± 3.5 mm (3–17 mm), and the mean time from the onset to treatment was 46.3 ± 98.4 days (0–300 days). The embolization state immediately after the procedure was complete occlusion in seven, neck remnant in eight, and body filling (BF) in eight cases. Total recovery was observed in nine, subtotal recovery in 11, and partial recovery in three cases. The mean time to any improvement in ONP was 6.0 ± 6.0 months (0.5–25 months). Comparing 20 cases with total plus subtotal recovery and three cases with partial recovery, five (25.0%) and three (100%) cases showed BF immediately after the procedure, respectively, which was statistically significant (P = 0.015).

Conclusion: The analysis indicated that coil embolization for the treatment of PComAAn with ONP resulted in satisfactory recovery of ONP in 87% of the cases and the outcome of aneurysm embolization was related to improvement in ONP.

Objective: We report a case in which coil embolization using crossing Y-configuration stenting was effective for an internal carotid-posterior communicating artery (IC-PC) aneurysm with repeated recurrence after clipping.

Case Presentation: The patient was a 57-year-old woman. Nine months after undergoing clipping for a ruptured right IC-PC aneurysm at 55 years of age, she developed a second subarachnoid hemorrhage (SAH) due to recurrence of the aneurysm and underwent clipping at the same site. A third SAH due to rupture of the left IC-PC aneurysm developed 1.5 years after the second clipping. Simultaneously, recurrence of a right IC-PC aneurysm was noted and she was referred to our department. The recurrent right IC-PC aneurysm was considered to have originated from the distal to the initial neck. It was 7 mm in size and had an irregularly shaped wide neck. As it was assumed that there would be marked adhesion due to repeated surgery, we decided to treat the aneurysm by coil embolization instead of direct surgery. Although the aneurysm neck partially involved the posterior communicating artery (Pcom), tight packing with a minimal residual neck was required. Therefore, crossing Y-configuration stenting was deployed on the internal carotid artery and Pcom using two Neuroform Atlas stents, and coil embolization was performed by the jail technique. The recurrent aneurysm was obliterated. There were no deficits or thrombotic complications after surgery. On DSA follow-up, no compaction or recurrence was observed, and the Pcom was well visualized one year later.

Conclusion: Coil embolization by crossing Y-configuration stenting is a viable treatment option for a recurrent IC-PC wide neck aneurysm.

Objective: Parkinsonism caused by dural arteriovenous fistula (DAVF) is very rare, however, it is reversible by endovascular treatment. We herein report a case of parkinsonism caused by DAVF with review of previous literature.

Case Presentation: An 87-year-old woman with parkinsonism and dementia was admitted to our hospital with disturbance of consciousness and aggravated parkinsonism symptoms. Plain CT revealed low-density areas in the brainstem and left cerebellar peduncle. Magnetic resonance images revealed hyperintense lesions on FLAIR, which had elevated apparent diffusion coefficient (ADC) values, in the same lesion of plain CT. However, no edematous change was detected. CT angiograms revealed obstruction of the left transverse and sigmoid sinuses. Dilations of the left superior petrosal sinus, left petrosal vein, and pontine veins were also noted. A low-density area on plain CT had a contrast effect. Cerebral angiography revealed a DAVF involving the left transverse sinus and fed by the left occipital and left middle meningeal arteries. Transarterial embolization (TAE) with Onyx obliterated the DAVF, and parkinsonism symptoms gradually improved. We reviewed 21 DAVF-derived parkinsonism cases, most of which were treated by TAE. Recent cases were treated with Onyx. In many cases, parkinsonism improved after endovascular treatment.

Conclusion: DAVF-derived parkinsonism is rare but treatable by endovascular therapy. DAVF should be one of the differential diagnosis of the parkinsonisms.

Objective: We report a patient with normal imaging findings at the onset of preceding headache who developed subarachnoid hemorrhage (SAH) due to intracranial vertebral artery dissection 7 days later.

Case Presentation: A 51-year-old woman with a history of chronic headache visited our emergency outpatient department with a complaint of mild to moderate right nuchal pain. CT, MRA, and MRI (diffusion-weighted image, T2-weighted image, FLAIR, MR cisternography, and basi-parallel anatomical scanning) were normal. Seven days later, she was admitted to our hospital with sudden disturbance of consciousness. CT revealed SAH and CTA demonstrated dilatation of the right vertebral artery (VA). The dilated lesion with an intimal flap on the right VA proximal to the posterior inferior cerebellar artery was confirmed on DSA. The dilated lesion and the proximal VA were occluded endovascularly using coils. The condition of the patient improved gradually, and she was transferred to the rehabilitation hospital on day 45 with a modified Rankin Scale score of 2.

Conclusion: The clinical course of the presented case, although rare, should be kept in mind in daily clinical practice.

Objective: We report a patient with acute bihemispheric infarction who underwent mechanical thrombectomy.

Case Presentation: A 76-year-old man suddenly developed coma and quadriplegia. Brain MRI and MRA revealed acute bihemispheric infarction due to occlusions of both the internal carotid arteries (ICAs). According to the DSA findings, we considered the left ICA as chronic occlusion and the right as acute. Mechanical thrombectomy for the right ICA occlusion was performed. Total recanalization was achieved using a stent retriever 181 minutes after onset. The left hemisphere was perfused by cross circulation through the anterior communicating artery, but the symptoms did not improve. MRI the day after thrombectomy showed extensive bihemispheric infarction. Recanalization for the bilateral hemispheres was maintained, although the left ICA remained occluded. He died 2 months later due to gastrointestinal bleeding.

Conclusion: Acute bihemispheric infarction due to occlusions of both ICAs is a rare entity. The symptoms are very severe and the therapeutic time window is extremely short because of absent collateral pathways. We should consider pre-existing carotid occlusive disease, determine whether the occlusions are acute or chronic, and perform prompt therapy. Further investigation is warranted to obtain a better outcome.

Objective: During percutaneous transluminal angioplasty (PTA) for the vertebral artery, occlusion of the subclavian artery using a balloon guiding catheter may be useful to prevent embolism of clots and/or debris distal to an atherosclerotic lesion. However, when placing a balloon guiding catheter at the intended vessels is difficult, it may be useful to use an aspiration catheter (AC) for mechanical thrombectomy as an intermediate catheter to suction way clots and/or debris. We report two cases in which PTA was performed for an atherosclerotic lesion at the intracranial vertebral artery using an AC, which ended without complications.

Case Presentations: Case 1: A 74-year-old man presented with dysarthria and was admitted to our hospital. MRI revealed severe left vertebral artery stenosis and diffuse cerebral infarct areas at the territory of the posterior circulation. The patient had an abdominal aortic aneurysm and abnormally shaped left tortuous subclavian artery. Therefore, we performed PTA and stenting via the left brachial artery. We guided a 6-Fr long sheath to the left subclavian artery, and a 6-Fr AC for thrombectomy was guided through the long sheath to the V4 portion of the left vertebral artery. Thereafter, PTA was carried out under manual aspiration from the AC. As restenosis at the atherosclerotic lesion occurred after PTA, we performed stenting using a coronary stent system for this lesion under manual aspiration from the AC. No new infarct areas were observed on post-procedural MRI. Case 2: A 74-year-old woman presented with dysarthria and was admitted to our hospital. MRI demonstrated basilar artery occlusion and diffuse cerebral infarct areas at the territory of the posterior circulation. As her symptom worsened after admission, we performed urgent mechanical thrombectomy. We first performed thrombectomy using a stent retriever and then performed PTA and stenting (PTAS) for residual basilar artery stenosis via the AC under manual aspiration.

Conclusion: When it is difficult to place a guiding catheter at the intended vessels during PTA, an AC may be useful to prevent distal embolization.