Objective: The effects of treatment methods for ruptured aneurysms on the incidence of vasospasm and normal pressure hydrocephalus (NPH) following subarachnoid hemorrhage (SAH) are controversial. We retrospectively examined the Nagasaki SAH registry data, and the complication rates of symptomatic vasospasm and NPH were analyzed based on the treatment methods.

Methods: Between January 2015 and December 2017, 800 SAH patients were registered from 18 hospitals, and their age, sex, World Federation of Neurological Societies (WFNS) grade, Fisher group, size and location of cerebral aneurysms, treatment methods, incidence of symptomatic vasospasm and shunt-dependent hydrocephalus, and prognosis (discharge or 3 months later) were retrospectively analyzed. The effects of treatment methods for the ruptured aneurysm on the incidence of symptomatic vasospasm and shunt-dependent hydrocephalus were then statistically analyzed.

Results: The mean age was 66.2 years old. There were 245 (30.6%) male patients and 555 (69.3%) female patients. Cerebral aneurysms were identified in 708 patients (87.5%) and surgical treatments were performed for 620. Neck clipping was employed in 416 patients (67.1%) and coil embolization was employed in 180 (29.0%). Symptomatic vasospasm developed in 118 (28.4%) in the clipping group and 30 (16.7%) in the coiling group (P = 0.0024). NPH developed in 148 (35.6%) in the clipping group and 42 (23.3%) in the coiling group (P = 0.0032). Vasospasm was listed as a major factor for an unfavorable outcome in 23 patients (8.9%) and as a minor factor in 33 (13.3%). NPH was listed as a major factor for an unfavorable outcome in 19 patients (3.5%) and as a minor factor in 46 (18.5%).

Conclusions: The multicenter registry study demonstrated lower incidences of both symptomatic vasospasms and NPH in the coiling group than in the clipping group. This superiority may result in better outcomes in the coiling group.

Objective: Mechanical thrombectomy for acute large vessel occlusion (LVO) is currently widely performed. However, rescue treatment (RT), such as percutaneous transluminal angioplasty (PTA) and stenting, is occasionally required, particularly in the case of atherothrombotic brain infarction (ATBI) or dissection. As RT requires higher levels of therapeutic skills and additional devices, early prediction of its performance and preparation are important. We retrospectively investigated the pre-therapeutic factors for predicting the necessity of RT.

Methods: We reviewed 149 consecutive patients who underwent mechanical thrombectomy for acute LVO between April 2014 and December 2019. Eight patients were excluded because of missing clinical data. RT was performed when severe stenosis was observed in occluded vessels or proximal to them during mechanical thrombectomy. We investigated pre-therapeutic neurological, laboratory, and radiological findings in the 141 remaining patients, and compared them between RT and non-RT groups.

Results: RT was performed on 23 of the 141 patients. We found four pre-therapeutic factors with significantly different rates between RT/non-RT as follows: (1) Atrial fibrillation 8.7%/71.1% (p <0.001), (2) diabetes mellitus 39.1%/19.5% (p = 0.04), (3) susceptibility vessel sign (SVS) by T2-weighted imaging 17.4%/66.1% (p <0.001), and (4) tapered occlusion by magnetic resonance angiography (MRA) 47.8%/11.9% (p <0.001). The plasma level of brain natriuretic peptide (BNP) was also significantly different between the two groups. When the BNP level was less than 70 pg/mL, the sensitivity for being in the RT group was 86.9% and the specificity was 83.5%.

Conclusion: Pre-therapeutic findings, such as diabetes mellitus, tapered occlusion, absence of atrial fibrillation, negative SVS, and BNP level less than 70 pg/mL, are predictors of RT in mechanical thrombectomy.

Objective: The efficacy of endovascular treatment for middle cerebral artery (MCA) aneurysms remains controversial. However, recent studies have reported the safety of endovascular treatment for MCA aneurysms. In this study, we studied the efficacy and clinical outcomes of endovascular treatment for MCA aneurysms in our hospital and the morphology and anatomy of MCA aneurysms that were suitable for endovascular treatment.

Methods: We retrospectively analyzed 26 cases of MCA aneurysms which had undergone endovascular treatment at our institution between January 2015 and October 2018. We studied sizes and shapes of the aneurysms, clinical and angiographical outcomes one year after the treatment, and complications in these 26 patients. We also compared the differences in these parameters of the 26 patients with those of 61 other patients who were treated with clipping during the same period.

Results: The median aneurysm size was 6.1 mm (1.8–29.9 mm), with the shapes of the aneurysms irregular in 8, and round in the other 18 cases. Four cases (15.4%) had ruptured aneurysms. All aneurysms were treated with assist techniques; 8 (30.8%) were treated by stent-assisted technique and 18 (69.2%) were treated by balloon-assisted technique and endovascular treatment was successfully performed in all (100%) cases. While the aneurysms were completely obliterated in 22 of them (84.6%), the remaining 4 cases (15.4%) had neck remnants. We observed periprocedural complications in 5 of the 26 (19.2%) aneurysms, all of which were transient and completely recovered during the follow-up period. The efficacy and complication rates were not different from the MCA aneurysms treated with clipping. All MCA aneurysms arising from the M1 trunk were treated with endovascular treatment, and those with a round shape with the axis not deviating from M1 were also treated with endovascular treatment.

Conclusion: Endovascular treatment for MCA aneurysms is safe and effective together with adjunctive techniques such as balloon-assisted technique or stent-assisted technique. Thus, M1 trunk aneurysms and MCA bifurcation aneurysms with a round shape along the same axis of MCA may be good indications for endovascular treatment. However, long-term clinical and angiographical outcomes remain unknown. Thus, further studies are needed to address the existing limitations.

Objective: The purpose of this study was to examine the efficacy and safety of mechanical thrombectomy in patients with acute occlusion of a large cerebral artery in the anterior circulation beyond 6 hours of the time last known to be well using the real-world clinical data collected from non-urban areas of Japan.

Methods: We analyzed a retrospective multicenter database collected at 10 thrombectomy capable primary stroke centers in Fukushima Prefecture. In all, 188 patients were presenting a large cerebral artery occlusion in the anterior circulation, that is, internal carotid and middle cerebral artery (M1 and M2 segment). In all, 158 patients received mechanical thrombectomy within 6 hours from symptom onset (early time window), and 30 patients exceeded 6 hours (late time window). We compared the patient background, outcomes, and safety variables between the two groups. The modified Rankin Scale (mRS) score of 0–2 at 90 days after treatment and the incidence of symptomatic intracranial hemorrhage were compared between groups to evaluate treatment efficacy and safety.

Results: There was no significant difference in the proportion of mRS score 0–2 at 90 days after treatment (51.3 vs. 46.7%: P = 0.644). However, symptomatic intracranial hemorrhage was more frequent in the late time window group (7.0 vs. 16.7%: P = 0.081). Symptomatic intracranial hemorrhage was a significant factor of a poor functional outcome in the late time window group (P = 0.022).

Conclusion: This study reflects the real-world results of mechanical thrombectomy in the non-urban areas of Japan. The treatment efficacy in the late time window patients was equivalent to that in the early time window patients. On the other hand, the incidence of symptomatic intracranial hemorrhage showed a trend to high in patients beyond 6 hours, which was a significant factor related to a poor functional outcome.

Objective: In coil embolization of ruptured cerebral aneurysms, intraoperative cerebral aneurysm re-rupture and thromboembolism are of concern. A good embolic condition can be expected by adjunctive techniques, but there is an increased risk of complications. We investigated the treatment results by coil embolization procedures for ruptured cerebral aneurysms.

Methods: Between January 2016 and December 2019, 75 ruptured saccular cerebral aneurysms were treated by coil embolization at our hospital. The background factors, results of aneurysm embolization, intraoperative re-rupture, symptomatic cerebral embolism, and other factors were investigated retrospectively. We compared and examined these factors based on the procedure.

Results: The mean age was 62.8 and there were 57 female patients (76.0%). The single catheter technique (SCT) was used in 44 cases (58.7%) and the adjunctive technique was used in 31 cases (41.3%). Complete obliteration (CO) was achieved in 24 cases (32.0%), there was a neck remnant (NR) in 23 (30.7%), body filling (BF) was observed in 28 (37.3%), intraoperative re-rupture occurred in 7 (9.3%), and symptomatic cerebral embolism developed in 6 (8.0%), but no postoperative re-rupture was observed. Retreatment was required in only three cases of SCT. On comparison by procedure, the incidence of symptomatic cerebral embolism was significantly lower in SCT group than in the adjunctive technique group (2.3% vs 16.1%, p = 0.04).

Conclusion: Among the cases of coil embolization for ruptured cerebral aneurysms at our hospital, SCT resulted in a lower incidence of symptomatic cerebral embolism than adjunctive techniques. It is essential to select an appropriate procedure in each case by understanding the characteristics of each procedure.

Objective: To ensure safe coil embolization for intracranial aneurysms, it is important to investigate the contact force between the coil and the aneurysm wall. However, it is unclear how the catheter tip position and the diameter of the secondary loop of the coil influence the contact force. In this study, we measured the contact force between a coil and an aneurysm biomodel under different conditions.

Methods: A commercially available coil was inserted through a microcatheter into a silicone rubber aneurysm model at a constant speed (1 mm/s) using an automatic stage, and the contact force between the coil and the aneurysm wall was measured by a force sensor attached on the aneurysm model. The inner diameter of the spherical aneurysm was 5 mm. The effects of varying the position of the catheter tip (near dome, center, near neck) and the diameter of the secondary coil (4.5 mm) were evaluated.

Results: When the catheter tip was inserted more deeply into the aneurysm (especially near the dome), the contact force increased. The contact force also increased as the secondary coil diameter was increased with the catheter tip near and in the center of the dome.

Conclusion: These results suggest that the catheter tip position and the secondary coil diameter affect the contact force. In particular, the contact force should be considered large with the catheter tip near the dome to ensure safe coil deployment.

Objective: Rupture of intracranial aneurysms after tissue plasminogen activator (t-PA) administration for acute ischemic stroke with an unruptured cerebral aneurysm is rare. We report a case of ruptured cerebral aneurysm after t-PA administration.

Case Presentation: A 74-year-old woman with dysarthria and left hemiparesis was admitted to our hospital, and acute lacunar infarction was found in the right corona radiata. One hour after t-PA administration, she complained of sudden headache and nausea, and her consciousness level deteriorated. Subarachnoid hemorrhage due to rupture of the anterior communicating aneurysm was confirmed and coil embolization was performed.

Conclusion: T-PA administration for acute ischemic stroke with an unruptured cerebral aneurysm risks rupture of the cerebral aneurysm, and careful judgment is needed in each case.

Objective: Coronavirus disease 2019 (COVID-19) is characterized by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and presents with respiratory symptoms. Overall, 5.7% of COVID-19 patients with severe respiratory status have been reported to develop acute cerebrovascular diseases (CVDs), and 41.3% of COVID-19 cases were considered nosocomial infections. Therefore, Protected Code Stroke, which is a guideline for acute stroke management that takes into account the safety of healthcare workers, has been developed. We created an operational manual for COVID-19 in the endovascular treatment center of our hospital and report our experience treating acute stroke in a COVID-19 patient.

Case Presentation: A 67-year-old man presented with a 5-day history of fever. Chest CT showed ground glass opacity (GGO) on admission, and the polymerase chain reaction (PCR) test for COVID-19 was positive. Dysarthria, right-sided hemiparesis, and aphasia were discovered on the morning of the third day after hospitalization. MRI showed an acute ischemic stroke at the left corona radiata and occlusion of the left middle cerebral artery (MCA). Progression of right-sided hemiparesis and exacerbation of respiratory status developed after the MRI. Tracheal intubation was performed, and the patient was treated with intravenous alteplase and mechanical thrombectomy (MT). Recanalization of blood flow was not obtained, and the neurological deficits remained.

Conclusion: MT was performed for large-vessel occlusion (LVO) in a COVID-19 patient during the COVID-19 pandemic. Safety for healthcare workers and appropriate rapid treatment for acute stroke patients are both vital in the current environment.

Objective: There is no established method for preventing vertebral artery embolization in percutaneous transluminal angioplasty (PTA) for subclavian artery stenosis. We manually compressed the supraclavicular fossa outside the sternocleidomastoid muscle to disrupt vertebral artery blood flow and prevent embolism. We report the usefulness of this procedure.

Case Presentations: Between April 2017 and July 2018, three patients with severe stenosis of the subclavian artery of 80% or higher were examined. For these patients, subclavian artery stenting was performed. The approach was via the left brachial artery in one patient and right femoral artery in two patients. After crossing the lesion, the vertebral artery was manually compressed and angiography confirmed that blood flow was blocked. In all patients, stent placement was successfully performed and good dilatation was confirmed by angiography. There were no neurological complications and no findings suggestive of acute cerebral infarction were found on magnetic resonance imaging (MRI).

Conclusion: Prevention of distal embolism by manual compression is simple, does not require multiple catheters, and is useful for subclavian artery stenting.

Objective: We report a case of mid-thoracic spinal dural arteriovenous fistula (SDAVF) that was successfully treated by transarterial embolization using a distal access catheter (DAC).

Case Presentation: A 75-year-old male presented with about a 2-year history of slowly progressive bilateral lower extremity weakness and numbness. Spinal MRI revealed significant spinal cord lesions and flow voids below Th4. Spinal angiography revealed a mid-thoracic SDAVF. We performed a transarterial selective embolization using a 4.2Fr DAC combined with a 6Fr guiding catheter to obtain a stronger support. The fistula was completely occluded.

Conclusion: For endovascular embolization of SDAVF, especially in the case of mid-thoracic SDAVF, using a DAC can be one of the most powerful options to obtain a stronger support.