The crisis of the coronavirus disease (COVID-19) is causing damage to the social and medical community. However, extreme emergency neuro-interventions such as mechanical thrombectomy still require the healthcare workers to offer the appropriate treatment while preventing further spread of the infection. This article outlines the necessary steps in managing a possible COVID-19 patient starting from patient screening to personnel infection and environmental contamination measures.

Objective: There are regional disparities in endovascular thrombectomy, and problems with emergency transport systems and hospital collaboration when transferring need to be addressed. In this study, the clinical outcomes of endovascular thrombectomy for transferred patients were analyzed.

Methods: Acute ischemic stroke patients who underwent endovascular thrombectomy between January 2016 and March 2019 were enrolled. They were retrospectively reviewed and divided into the direct group and transfer group, and we compared treatment results and clinical outcomes between them.

Results: In all, 122 patients met the inclusion criteria, comprising 93 patients in the direct group and 29 patients in the transfer group. The time from onset to door of our hospital was longer in the transfer group than in the direct group (73 minutes vs. 158 minutes, P = 0.80), but the time from arrival to reperfusion was significantly shorter in the transfer group (139 minutes vs. 106 minutes, P = 0.001). As the time from onset to reperfusion did not differ significantly between the two groups (220 minutes vs. 256 minutes, P = 0.60), there was no significant difference in good outcome at discharge (38.7 vs. 41.3%, P = 0.79).

Conclusion: Clinical outcomes of transferred patients for endovascular thrombectomy may be equivalent to those of directly transported patients. Promoting close hospital cooperation may improve clinical outcomes and resolve regional disparities.

Objective: The efficacy and safety of aspiration thrombectomy using Penumbra catheter with acute large vessel occlusion in the anterior circulation have been reported in previous studies. In some cases, the carotid siphon (CS) is elongated, and with this anatomy, especially where there is bifurcation of the ophthalmic artery (OA), navigation of Penumbra catheters into distal internal carotid artery (ICA) is interrupted, which is known as the ‘ledge effect’. We investigate the anatomical characteristics of CS that cause interruption of navigation of the Penumbra catheter.

Methods: Between January 2015 and March 2018, mechanical thrombectomy using Penumbra 60 was performed on 51 patients with middle cerebral artery (MCA) or intracranial ICA occlusion. Patients were divided into two groups: The ‘ledge-effect’ group those in whom the Penumbra catheter was unable to be navigated into the distal ICA through the CS, and ‘no ledge-effect’ group those in whom this was possible. The anatomical characteristics of CS, the diameter of ICA, diameter of OA, OA/ICA ratio and radius of the CS were evaluated using angiographical imaging.

Results: The ‘ledge-effect’ group numbered eight cases (17%). Only the value of the CS radius was significantly smaller in the ledge-effect group (p = 0.0019), other parameters were not significantly different between the groups. The cutoff radius value was 3.62 mm.

Conclusion: The most notable anatomical factor affecting possibility of navigation of the Penumbra catheter through the CS was the CS radius. This could be useful information when devices used in mechanical thrombectomy are selected.

Objective: We report a case of reversible cerebral vasoconstriction syndrome (RCVS) that occurred during early pregnancy and improved by endovascular therapy (EVT).

Case Presentation: A 30-year-old Japanese woman at 8 weeks’ gestation presented with sudden occipital headache followed by left hemiparesis and convulsion. MRI on admission revealed acute infarction in the distribution of the right posterior cerebral artery (PCA), and MRA demonstrated multi-segmental vasoconstrictions in the posterior circulation. Since the episode and image findings were suggestive of RCVS and the patient was in the organogenesis period, intravenous magnesium sulfate was administered as a vasodilator. Her level of consciousness improved temporarily; however, she suddenly fell into a stupor on day 4 of the illness. Emergency MRI demonstrated a fresh infarction in the left side of pons, and the poorer visualization of the posterior circulation. We proposed selective intra-arterial infusion of nicardipine 1 mg over 1 minute through an indwelling microcatheter in the middle of the basilar artery. The left superior cerebellar artery (SCA) and P1 blood flow improved after the procedure. Her symptoms improved gradually, and follow-up MRA performed on day 15 was almost normal. Hence, we established a definite diagnosis of RCVS. She was discharged to recovery phase rehabilitation hospital with modified Rankin Scale 4 and National Institute of Health Stroke Scale (NIHSS) 5.

Conclusion: RCVS can occur in early pregnancy period, and EVT is a potential therapeutic option for RCVS in this condition.

Objective: Treatment of an unruptured aneurysm at the origin of duplicated middle cerebral artery (DMCA) by coil embolization using balloon remodeling has not been reported. We report a case of coil embolization using balloon remodeling for an unruptured aneurysm at the origin of DMCA.

Case Presentation: A 71-year-old female was found to have an unruptured aneurysm at the origin of DMCA during an examination for headache. Coil embolization using balloon remodeling for the wide neck aneurysm to preserve both the internal carotid artery (ICA) and DMCA was successful. The perioperative course was uneventful.

Conclusion: This treatment enables complete embolization, and preserves both the ICA and DMCA. Thus, it is useful for aneurysms at the origin of DMCA.

Objective: Among 36 cerebral aneurysm cases of stent-assisted coil embolization with the Neuroform Atlas since April 2017, there were three cases of stent migration during the operation. The status of stent deployment, cause of trouble, results of coil embolization, and complications were assessed.

Case Presentations: There were two cases with trouble during stent deployment, a case of internal carotid artery aneurysm, and a case of middle cerebral artery (MCA) aneurysm. The proximal marker of the stent was advanced during stent deployment with the simple pull maneuver, then a part of the stent migrated to the aneurysm sac in both cases. Stent migration to the aneurysm sac during microcatheter navigation by the trans-cell technique occurred in another MCA aneurysm case. No postoperative complications were observed, and a volume embolization ratio (VER) of 24.1%–33% was achieved in these three cases.

Conclusions: The Neuroform Atlas is a safe and convenient stent system. However, stent advancement during deployment and migration during trans-cell microcatheter navigation can occur.

Objective: We report a survived case of acute bilateral internal carotid artery occlusion successfully treated by mechanical thrombectomy.

Case Presentation: The patient was an 82-year-old right-handed man. Sudden consciousness disturbance and aphasia appeared, and cranial magnetic resonance angiography (MRA) revealed bilateral internal carotid artery occlusion. Cerebral angiography demonstrated occlusion between the cervical and cavernous portions of the bilateral internal carotid artery, and the growth of collateral circulation to the areas where the bilateral internal carotid artery perfused. We performed mechanical thrombectomy first on the left side, which was the main cause of his symptoms and relatively wide ischemic penumbra, and achieved recanalization of the bilateral internal carotid artery and suppressed extensive enlargement of the infarction.

Conclusion: Acute bilateral internal carotid artery occlusion requires an optimal treatment strategy based on the clinical symptoms and preoperative imaging.