While mechanical thrombectomy is known to be effective for distal medium vessel occlusion (DMVO) as well as large vessel occlusion, tortuous DMVO are predisposed to vessel injury during stent retriever thrombectomy. Furthermore, getting access to the thrombus may be difficult during suction thrombectomy using a dedicated suction catheter. Most studies describe DMVO treatment using stent retrievers and dedicated suction catheters, but there are limited studies reporting DMVO treated with suction thrombectomy using a microcatheter. Herein, we describe three cases of DMVO treated with suction thrombectomy that was performed using a microcatheter and subsequently showed good results. Therefore, suction thrombectomy using a microcatheter is a viable alternative treatment for tortuous DMVO.

Aortic dissection is one of the causes of acute ischemic stroke. Endovascular recanalization therapy (EVT) has emerged as an essential treatment for acute ischemic stroke due to large artery occlusion. However, it is rarely performed in the situation of hidden aortic dissection (AD). Two patients presented to the emergency room with focal neurologic deficits. The first patient was diagnosed with right internal carotid artery (ICA) occlusion. Angiography revealed that the ICA was occluded by the dissection flap. After a stent deployment in the proximal ICA, the antegrade flow was restored. The patient was diagnosed with AD on chest computed tomography (CT) after EVT. For the second patient, intraarterial thrombectomy was performed to treat left middle cerebral artery occlusion. AD was first detected on echocardiography, which was performed after EVT. Herein, we report successful endovascular recanalization therapy performed in two patients with acute ischemic stroke in the situation of undiagnosed aortic dissection. We also reviewed previous case reports and relevant literature.

Syncope is a common symptom in clinical practice. Rotational vertebral artery occlusion syndrome, also referred to as Bow Hunter’s syndrome (BHS), is a rare condition associated with syncope and is caused by mechanical occlusion or stenosis secondary to mechanical compression of the vertebral artery during head rotation. BHS is associated with a multifactorial etiology; however, in most cases, this condition is attributed to degenerative changes. A 53-year-old man visited our hospital for the evaluation of fainting and dizziness episodes that occurred when he turned his head. Evaluation as an outpatient in the Department of Neurology showed a positive result on the Frenzel goggle test. Transfemoral cerebral angiography performed at the Department of Neurosurgery revealed stenosis of the proximal right vertebral artery. Complete occlusion of the vertebral artery was observed, and the head was turned to the right. Decompression and fusion were performed, and the contributory lesion was completely removed. Postoperative imaging confirmed complete removal of the spur and sufficient vertebral artery decompression; the patient’s symptoms resolved postoperatively.

Symptomatic Rathke’s cleft cysts (RCCs) can be treated by surgical procedures, usually through an endonasal transsphenoidal corridor using either a microscope or an endoscope. We report a large suprasellar extended RCC causing obstructive hydrocephalus, which was efficiently managed by a novel surgical route named “reverse” trans-sellar approach using transventricular neuroendoscopy. A 48-yearold woman complained of persistent headache and a tendency to fall that had begun 6 months previously. The images obtained from MRI scan showed intra- and supra-sellar cystic masses occupying the third ventricle with obstruction of the foramina of Monro and the aqueduct of Sylvius. The cystic wall showed a slight enhancement, and the cystic contents showed iso-signal intensity on T1-and T2-weighted images. Instead of trans-nasal trans-sellar surgery, we decided to operate using a conventional transventricular endoscope. A thin cystic capsule, which blocked the foramina of Monro and the aqueduct of Sylvius, was fenestrated and removed and a third ventriculostomy was performed. The defect in the infundibulum between sellar and suprasellar cysts was widened and used as a corridor to drain cystic contents (reverse trans-sellar route). The final pathological finding revealed an RCC with focal metaplasia. We efficiently managed a large RCC by transventricular neuroendoscopic surgery with cyst fenestration and third ventriculostomy and simultaneously drained the sellar contents using a novel surgical route. Reverse trans-sellar neuroendoscopic surgery is a relevant treatment option for selective patients with large suprasellar extensions of RCCs.

Background: Anterior choroidal artery (AchA) aneurysms are usually small in diameter because of the size of the involved artery and are often wide-necked. Coil embolization of AchA aneurysm is thus challenging because of serious risks, such as thromboembolic occlusion of artery and perforation of aneurysm dome. Therefore, aneurysmal neck clipping remains widely performed despite a recent increase in the use of coil embolization for aneurysm treatment. We report the treatment results of AchA aneurysms mostly (92.3%) treated with coil embolization at our institute. Methods: The database and medical records of patients who underwent coil embolization for AchA aneurysms were retrospectively analyzed. The clinical and imaging results and procedure-related complications were investigated after coil embolization performed between January 2006 and March 2022 at our institute. Results: In total, 96 AchA aneurysms comprising 65 unruptured and 31 ruptured aneurysms, including only 1 ruptured aneurysm (1.0%) re-embolized at postoperative day 192 because of coil compaction, were evaluated. After the initial coil embolization, complete occlusion was attained in 41, residual neck in 45, and residual aneurysm in 10 patients. Follow-up radiological studies after 6–174 months were performed for 80 aneurysms. Complete occlusion was noted in 57 patients, residual neck in 22, and residual aneurysm in 1. The dysarthria experienced by one (1.0%) patient was the only symptomatic procedure-related complication. After coil embolization, neither delayed new rupture nor re-rupture was observed. Conclusions The results of this study demonstrate that coil embolization is a safe and effective treatment option for patients with AchA aneurysms.

Radiation-induced cavernous hemangiomas (RICHs) have been increasingly reported as a late complication after conventional radiotherapy. RICH after stereotactic radiosurgery (SRS) is extremely rare and the few cases have been reported to demonstrate their properties. A 72-year-old female patient presented with progressive neurologic deficits. She underwent tumor surgery for meningioma 13 years ago and two times of SRS for treating a residual tumor. Newly-developed mass was 4.3 cm-sized heterogeneously enhancing mass with severe cerebral edema. She underwent surgical resection and the histologic examinations revealed organized hematoma. Finally, it was diagnosed as a RICH following SRS based on radiological and histological findings and a history of multiple radiosurgeries. Clinical, radiological, and histological features of a RICH following SRS were discussed in this report.

Background: and Purpose: Neural stem cells (NSCs) have the ability to regenerate, proliferate, and differentiate, enabling them to play important roles in the recovery of the damaged nervous system. However, in neurodegenerative diseases such as Alzheimer's disease (AD), the NSCs are damaged as well. Glia-like cells from human mesenchymal stem cells (ghMSCs) are functionally enhanced adult stem cells. In the present study, we investigated whether ghMSCs could protect NSCs from amyloid beta (Aβ)-mediated toxicity. Methods: Rat NSCs were obtained from E13–14 fetal rat cortices. NSCs were seeded in pre-coated plates, and the next day, cells were simultaneously treated with 20 μM Aβ and 0.4 μm pore insert well-seeded ghMSCs. After 48 hours of co-treatment, cell viability and proliferation were evaluated. After 2 hours of co-treatment, western blotting was performed to measure inflammasome-related factors, such as NOD-like receptor family pyrin domain containing 3, caspase-1, and interleukin-1β. Results: The results showed that ghMSCs increased viability and proliferation and reduced the toxicity of NSCs injured by Aβ by reducing the NRLP3 inflammasome activation of NSCs induced by Aβ. Conclusions In this study, we confirmed that ghMSCs could protect NSCs in an in vitro model of AD through the regulation of inflammatory response.

The crossing Y-stent method is one of the indispensable techniques to achieve sufficient neck coverage during coil embolization of bifurcation aneurysms with a wide neck and/or branch incorporation. However, the inevitable hourglass-like expansion of the second stent at the crossing point can result in insufficient vessel wall apposition, reduced aneurysm neck coverage, delayed endothelialization, and subsequent higher risks of acute or delayed thrombosis. It also interferes with engagement of the microcatheter into the aneurysm after stent installation. We expected to be able to reduce these disadvantages by installing a noncrossing type Y-stent using the Solitaire AB stent, which is fully retrievable with a tapered proximal end. Here we report the techniques and two successful cases.

Background: and Purpose: Neural stem cells (NSCs) have the ability to regenerate, proliferate, and differentiate, enabling them to play important roles in the recovery of the damaged nervous system. However, in neurodegenerative diseases such as Alzheimer's disease (AD), the NSCs are damaged as well. Glia-like cells from human mesenchymal stem cells (ghMSCs) are functionally enhanced adult stem cells. In the present study, we investigated whether ghMSCs could protect NSCs from amyloid beta (Aβ)-mediated toxicity. Methods: Rat NSCs were obtained from E13–14 fetal rat cortices. NSCs were seeded in pre-coated plates, and the next day, cells were simultaneously treated with 20 μM Aβ and 0.4 μm pore insert well-seeded ghMSCs. After 48 hours of co-treatment, cell viability and proliferation were evaluated. After 2 hours of co-treatment, western blotting was performed to measure inflammasome-related factors, such as NOD-like receptor family pyrin domain containing 3, caspase-1, and interleukin-1β. Results: The results showed that ghMSCs increased viability and proliferation and reduced the toxicity of NSCs injured by Aβ by reducing the NRLP3 inflammasome activation of NSCs induced by Aβ. Conclusions In this study, we confirmed that ghMSCs could protect NSCs in an in vitro model of AD through the regulation of inflammatory response.

Objective: As the average life span in modern society continues to increase, much interest is focused on high-risk procedures in elderly patients, including major surgical operations. We investigated the results of endovascular coiling of unruptured intracranial aneurysms (UIA) in patients over 80 years of age. Methods: We retrospectively analyzed 39 patients aged over 80 years who underwent coil embolization for UIA between April 2007 and April 2019 at our hospital. Results: Complete occlusion on digital subtraction angiography (DSA) immediately after surgery was performed in 44 (84.6%) of 52 cases of cerebral aneurysms. Four patients (7.7%) had residual aneurysmal necks, and four (7.7%) had contrast flow in the aneurysmal sac. Follow-up magnetic resonance angiography (mean: 8.2 months) was performed in 37 aneurysms in 24 patients. There was evidence of blood flow in the neck in seven cases (18.9%) and aneurysm in two cases (5.4%). Follow-up DSA (mean: 20.5 months) was performed in 14 aneurysms in 11 patients, and 11 aneurysms (78.6%) had complete occlusion, 1 aneurysm (7.1%) had an aneurysmal neck, and 2 aneurysms (14.3%) had contrast filling into the aneurysmal sac. Coil embolization procedure-related complications occurred in 3 patients (7.7%). Cerebral infarction occurred in 1 (2.6%), arterial dissection in 1 (2.6%), and hypoesthesia in 1 (2.6%). Conclusions Active treatment of UIA in elderly patients over 80 years of age through endovascular coil embolization can be considered.