Objective: Intraprocedural rupture (IPR) is a rare complication that can occur during endovascular treatment (EVT) of unruptured intracranial aneurysms (UIAs). However, it leads to high morbidity and mortality rates. Others have showed that coil flexibility is a risk factor for IPR. Neuroform Atlas (NA) stents can be deployed with 0.0165-inch microcatheters to enable stent assisted coiling (SAC) with a high likelihood. Undersized flexible coils can be inserted initially during SAC. This study aimed to determine whether SAC using NA and highly flexible coils for UIAs can be conducted without IPR.

Methods: We retrospectively analyzed nine consecutive patients (mean age, 73.2 years; female, n = 6) who underwent SAC for UIAs combined with NA stents and undersized flexible coils between January 2017 and December 2019. Two aneurysms were located at the internal carotid artery (ICA), and one each was located at the ICA-posterior communicating, anterior communicating, middle cerebral, vertebral, vertebra-posterior inferior cerebral and basilar arteries. The mean size of the aneurysms was 4.6 (range, 3.1–8.6) mm. SAC proceeded using the jailing technique. All coils were selected from among the most flexible coils available. We retrospectively assessed technical success rates, aneurysm occlusion at final digital subtraction angiography (DSA), volume embolization ratios (VERs), rates of IPR and symptomatic stroke within 30 days, angiographic findings of aneurysm occlusion at 3 months post-procedure and late adverse events (frequency of aneurysmal rupture, ipsilateral ischemic stroke, and retreated targeted aneurysms).

Results: The technical success rate was 100%. Complete occlusion (CO) was immediate in 8 (89%) patients and a neck remnant persisted in 1 (11%). No IPR or symptomatic stroke developed within 30 days. During a mean follow-up period of 11.8 months, CO persisted in 8 (89%) patients. No late adverse events occurred.

Conclusion: The early clinical and angiographic findings of SAC for UIAs combined with an NA stent and undersized flexible coils were favorable for this series.

Objective: Endovascular treatment of anterior communicating artery aneurysms is difficult due to their complex anatomical structure. We retrospectively analyzed the relationships among the anatomical features, initial microcatheter positions, and initial occlusion outcomes.

Methods: In all, 66 cases were treated at our hospital. We investigated the relationships among the anatomical features of the aneurysm and A1 segment of the anterior cerebral artery (ACA), treatment procedures, and initial occlusion outcomes. We divided the initial microcatheter positions into greater and lesser curvatures based on the curvature from A1 to the aneurysm, and evaluated the outcomes.

Results: In total, 54 out of 66 patients (82%) achieved complete obliteration (CO) or had residual neck (RN) aneurysms, and 12 had residual aneurysms (RAs: 18%). Neck diameters and superior position aneurysms were correlated with initial occlusion outcomes in the multivariate analysis. The relationship between initial occlusion outcomes and initial microcatheter positions in superior position aneurysms (37 patients) was then examined. Eleven out of 26 patients (42.3%) had residual aneurysms at the greater curvature microcatheter position, whereas no residual aneurysms were detected at the lesser curvature microcatheter position. The A1 angle was not correlated with the outcomes.

Conclusion: Wide-necked aneurysms and superior position aneurysms were identified as factors leading to incomplete occlusion in the endovascular treatment of anterior communicating artery aneurysms. The microcatheter position at the greater curvature in superior position aneurysms was a factor for incomplete occlusion. This suggests that guiding the microcatheter to the lesser curvature position of A1 is important in the treatment of superior position aneurysms.

Objective: Persistent primitive trigeminal artery (PPTA) is a rare condition in which a fetal carotid-basilar anastomosis persists into adulthood. PPTA aneurysms often necessitate endovascular treatment and adjunctive techniques, such as stent- or balloon-assisted techniques, are sometimes selected. This case report describes two women in their sixties with unruptured right PPTA aneurysms who underwent stent-assisted coil embolization procedures, with consideration of the anatomical features in each case.

Case Presentations: One patient presented with an aneurysm at the bifurcation of the PPTA and the basilar artery (BA), which was classified as Saltzman type 1 with a hypoplastic vertebral artery (VA)-BA system. A stent was deployed from the BA to the PPTA to cover the neck of the aneurysm and coil embolization was performed. The second patient presented with an aneurysm at the bifurcation of the PPTA and the internal carotid artery (ICA), which was classified as Saltzman type 2 with a hypoplastic VA-BA system. A stent was deployed from the PPTA to the petrous segment of the ICA covering the neck of the aneurysm and coil embolization was performed. In both patients, the 1-year follow-up digital subtraction angiography (DSA) showed that the aneurysms had not recurred.

Conclusion: The PPTA aneurysms were successfully treated with stent-assisted coil embolization. The treatment strategy should be devised in accordance with both the lesion site and the PPTA variant.

Objective: Rupture of blood blister-like aneurysm (BBA) of the internal carotid artery (ICA) may result in fatal subarachnoid hemorrhage (SAH). Open surgery including bypass surgery has been performed to treat the aneurysm. Recently, endovascular treatment is developing for the treatment of cerebral aneurysm. Here, we report a case of ruptured BBA of the ICA, treated by endovascular trapping and review the literatures.

Case Presentation: A 37-year-old woman was brought to our hospital to treat SAH. Computed tomography (CT) angiography showed no apparent cause of the hemorrhage except for the minor dilation of the C2 portion of the left ICA. After 3 days, the CT angiography demonstrated progression of the dilation with the formation of a bleb. Evaluating collateral circulation through anterior communicating artery, endovascular trapping of the ICA was performed. Although she suffered minor ischemic stroke postoperatively, the symptoms recovered completely and discharged without neurological deficit.

Review of Literatures: we reviewed the 11 cases of ruptured BBA treated by endovascular trapping. The results of ICA occlusion based on the evaluation of collateral circulation were satisfactory because rebleeding as well as regrowth of the aneurysm were prevented. However, hemodynamic compromise and treatment for vasospasm following SAH are considered.

Conclusion: Rebleeding from BBA of the ICA should be prevented first and ischemic complication is avoided secondary. Endovascular trapping following evaluation of the collateral circulation is definitive treatment of BBA of the ICA.

Objective: We report the case of a cavernous sinus dural arteriovenous fistula (CSdAVF) treated by transvenous embolization (TVE) via the jugular venous arch (JVA) connecting bilateral superficial cervical veins.

Case Presentation: A male patient in his 50s presenting with diplopia and headache was diagnosed with a CSdAVF. The first session of TVE resulted in incomplete obliteration of the fistula due to poor accessibility through the inferior petrosal sinus (IPS), and postoperative computed tomography angiography (CTA) disclosed a newly developed drainage route into the facial vein (FV) connecting to the anterior jugular vein (AJV) and the JVA. The patient underwent the second session of TVE through the JVA, FV, and the superior ophthalmic vein (SOV), and obliteration was achieved.

Conclusion: There is a considerable variation in the anatomy of facio-cervical veins in patients with CSdAVF. Meticulous preoperative evaluation of the venous drainage route using modern diagnostic tools is indispensable to achieve successful results in patients with CSdAVF.

Objective: We report a case of cardioembolic stroke treated by mechanical thrombectomy (MT) via the transfemoral approach under the assistance of intra-aortic balloon pumping (IABP).

Case Presentation: A 64-year-old man suddenly developed consciousness disturbance, aphasia, and left hemiparesis during intensive care for acute myocardial infarction (AMI) with IABP. The patient was transferred to our hospital and diagnosed with acute right middle cerebral artery (MCA) occlusion. We performed MT using a balloon-guiding catheter via the transfemoral approach and achieved complete recanalization.

Conclusion: Endovascular therapy for acute MCA M1 occlusion via the transfemoral route was safe even when the patient was treated using IABP.

Objective: We report a case of cerebral embolism from a bacterial embolus due to infective endocarditis (IE) during treatment of bacterial meningitis.

Case Presentation: During treatment of bacterial meningitis, an 82-year-old woman developed left middle cerebral artery embolism. Mechanical thrombectomy was performed, and the yellowish-white emboli were retrieved. From the culture and pathological findings of the embolus, the same bacteria as the meningitis, Streptococcus gordonii, was identified and was considered to originate from IE. She was treated by postoperative antibiotics, but was transferred to the rehabilitation hospital on the 37th postoperative day due to slight right hemiparesis.

Conclusion: We should always consider bacterial embolism in acute ischemic stroke combined with bacterial meningitis.

Objective: To report a case of mechanical thrombectomy (MT) for internal carotid artery (ICA) occlusion in a patient with polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes (POEMS) syndrome, a rare systemic disease associated with plasma cell proliferation.

Case Presentation: A 52-year-old woman was taking steroids due to autoimmune hepatitis. She was diagnosed with acute cerebral infarction due to left ICA occlusion. Although MT was performed, recanalization was not achieved. Therefore, recanalization was carried out using a vasodilator and percutaneous transluminal angioplasty (PTA) in combination.

Conclusion: PTA may be effective for large-vessel occlusion (LVO) in patients with POEMS syndrome.

Objective: Segmental arterial mediolysis (SAM) is a non-inflammatory and non-atherosclerotic vascular disease characterized by segmental medial defect/necrosis of muscular arteries as a result of mediolysis. SAM affects the visceral and intracranial arteries, and causes arterial dissection and aneurysm. We report a case of aneurysmal subarachnoid hemorrhage (SAH) followed by hemoperitoneum due to a ruptured visceral artery aneurysm.

Case Presentation: A 54-year-old man developed SAH from a ruptured anterior communicating artery aneurysm, which was clipped on the same day. Thereafter, he was treated to prevent cerebral vasospasm. Six days after onset, he developed acute anemia and his blood pressure decreased, suggesting hemorrhagic shock. Hemoperitoneum was detected on computed tomography and abdominal angiography was performed. Irregular and stenotic arterial findings, and an unusual aneurysm with contrast stasis were found in a branch vessel from the right gastroepiploic artery. SAM was diagnosed based on the clinical course and angiographic characteristics. Endovascular treatment consisted of embolization of the visceral artery aneurysm with liquid embolic material. after embolization, the vital signs stabilized and he recovered from shock. Acute treatment for SAH was continued. Although the patient did not develop vasospasm-related sequelae, he was transferred to the rehabilitation hospital 7 weeks after onset and his modified Rankin Scale score at 3 months after onset was 2.

Conclusion: Visceral artery aneurysm associated with SAM should be considered as the cause of hemoperitoneum with hemorrhagic shock during the acute phase of SAH.

Purpose: Endovascular therapy (EVT) through the tortuous access route is increasingly performed in neurovascular procedures. In the posterior circulation through the vertebral artery (VA), ischemic complications, including vessel dissection and cerebral vessel infarction, are sometimes observed, especially during navigation of the guiding catheter, because of small vessel diameter and tortuous origin. We describe an adjunctive technique for passing the guiding catheter safely to the tortuous VA and reducing ischemic complication using respiratory displacement of the aortic arch.

Case Presentations: The guidewire is advanced to the origin of the VA until it is caught in the tortuosity. Then we instruct the patient to take a maximum deep inspiration and hold his or her breath. In this manner, the aortic arch and side branches are dislocated to the caudal direction, which reduces the tortuosity of the VA origin and facilitates passage of the guidewire. Here, we discuss three representative cases which demonstrate that our techniques are effective in navigating the catheter to the tortuous VA.

Conclusion: In the EVT of a patient who has a tortuous VA, respiration control under local anesthesia, maximum deep inspiration, and breath holding induce the respiratory dislocation of the aortic arch. This enables safe navigation of the guiding catheter, reduces the likelihood of interruption in blood flow, and helps avoid dissection and ischemic complications during EVT.