Journal of Neuroendovascular Therapy
Online ISSN : 2186-2494
Print ISSN : 1882-4072
ISSN-L : 1882-4072
早期公開論文
早期公開論文の27件中1~27を表示しています
  • Haruki Amano, Yasuyuki Tatsuta, Yukitaka Yamashita, Naotsugu Hashiguch ...
    論文ID: tn.2024-0044
    発行日: 2024年
    [早期公開] 公開日: 2024/11/06
    ジャーナル オープンアクセス 早期公開

    Objective: Mechanical thrombectomy (MT) for acute ischemic stroke usually requires blind procedures when endovascular devices are advanced into the occluded vessels. Therefore, the visualization of occluded vessels could potentially achieve safer procedures, shorter procedural time, and progression of the reperfusion rate. We report on the usefulness of a novel technique in which a 3D roadmap of occluded vessels was created from a rapid 3D proton density-weighted (PDW) variable refocusing flip angle and turbo spin echo (VRFA-TSE) method.

    Case Presentation: 3D PDW VRFA-TSE imaging was performed in addition to routine MRI for 2 patients with middle cerebral artery occlusion. With the adjustments to the imaging parameters, we were able to perform 3D PDW imaging in less than 1 minute. Subsequently, a 3D image of the occluded vessels was constructed from these images. To create a 3D roadmap, the 3D PDW images were positioned with cone beam CT images obtained before MT using 3D-3D fusion. Because a neurological technician performed the imaging processing while doctors and nurses prepared for MT, practical loss time was approximately 2 minutes. MT was performed with reference to the 3D roadmap, and the occluded lesion was recanalized without complications in both patients. The 3D roadmap of the occluded vessels was well-matched with the recanalized vessels.

    Conclusion: A 3D roadmap created from rapid 3D PDW imaging is a useful assistance technique for MT that allows the visualization of occluded vessels.

  • Toru Kurokawa, Yuko Tanaka, Takeru Umemura, Junkoh Yamamoto
    論文ID: tn.2024-0085
    発行日: 2024年
    [早期公開] 公開日: 2024/11/06
    ジャーナル オープンアクセス 早期公開
    電子付録

    Objective: This report describes the creation of a freestanding cerebrovascular model with an attached Luer valve device and a bridge.

    Case Presentation: A left internal carotid artery aneurysm was discovered during a detailed examination of headaches in a 70-year-old woman. A vascular lumen model was created for the pretreatment simulation. The addition of a male Luer valve and bridge to the vascular lumen model created using the multistep vascular wall thickness method facilitated lumen washing, support material removal, self-support, and compatibility with medical devices.

    Conclusion: By adding Luer valves and struts and creating cerebral vascular lumen models with appropriate vessel wall thicknesses, we can enhance their efficiency, strength, and utility in preoperative simulations.

  • Kenji Yamada, Masashi Ikota, Nozomi Ishijima, Yoshikazu Yoshino
    論文ID: cr.2024-0071
    発行日: 2024年
    [早期公開] 公開日: 2024/10/31
    ジャーナル オープンアクセス 早期公開

    Objective: Dural arteriovenous fistulas (dAVFs) in the paracavernous sinus of the sphenoid wing often present challenges for transvenous access because of their complex venous drainage patterns. Herein, we report the successful diagnosis and treatment of a greater sphenoid wing dAVF using a percutaneous transvenous approach via the Labbé vein.

    Case Presentation: A 48-year-old woman presented with tinnitus and was diagnosed with a greater sphenoid wing dAVF. The dAVF was fed by multiple meningeal arteries from the accessory meningeal artery. Shunted blood drained retrogradely into the superficial middle cerebral vein (SMCV) and bilateral inferior petrosal sinus (IPS) via the cavernous sinus (CS). Although communication was observed between the shunt pouch and the lateral part of the CS, the tortuous and narrow nature of this connection suggests difficulty in accessing the shunt pouch via the IPS. Conversely, the SMCV, which served as the primary outflow pathway, was adequately connected to the vein of Labbé with minimal difficulty, facilitating the passage of the microcatheter. The percutaneous transvenous approach via the Labbé vein successfully reached the SMCV and achieved complete obliteration with selective transvenous embolization (TVE) using coils. The symptoms of the patient improved postoperatively, and the patient was discharged without complications.

    Conclusion: Greater sphenoid wing dAVFs often rely on the SMCV as the major drainage route, making venous approaches challenging. The route via the vein of Labbé through the cortical veins to reach the SMCV proved to be a valuable access route for TVE of greater sphenoid wing dAVFs.

  • Bumpei Yamasaki, Rei Goto, Hirotoshi Imamura, Jinichi Sasanuma
    論文ID: oa.2024-0058
    発行日: 2024年
    [早期公開] 公開日: 2024/10/29
    ジャーナル オープンアクセス 早期公開

    Objective: Mechanical thrombectomy (MT) is an important procedure in the treatment of acute cerebral infarction, and its effectiveness depends largely on timely intervention after the onset. In the United States, a tiered accreditation system of stoke centers has been established to provide MT efficiently. In Japan, however, despite the large number of medical institutions performing MT, the establishment of a tiered accreditation system has yet to be seen. The low number of cases treated per institution raises concerns about the economic sustainability of MT in Japan because significant capital and human resource investment are required. This study aims to investigate the cost structure of MT procedure and the break-even point in 2 different hospital settings in Japan.

    Methods: We conducted a detailed cost analysis of MT at 2 distinct hospitals: Hospital A, a large public hospital in a government-designated city, and Hospital B, a private non-profit hospital in the Tokyo metropolitan area. Data collection involved face-to-face interviews with department heads and a structured survey based on the Japanese Hospital Accounting Standards, focusing on material, labor, and facility-related costs. Break-even points were calculated considering both fixed and variable costs, with adjustments made for the shared use of facilities in Hospital B.

    Results: The total cost per case was 349256 yen in Hospital A and 245150 yen in Hospital B, respectively. The total cost per case was elevated to 559866 yen assuming only MT was performed at Hospital B. This figure was significantly higher than the reimbursement price of MT (331500 yen). The number of procedures needed to exceed the break-even point for MT was approximately 290 cases per year in Hospital A and 125 cases per year in Hospital B, respectively.

    Conclusion: We conducted a break-even analysis of MT based on an interview survey. The number of cases required to cross the break-even point for MT alone was much higher than the actual number of MT procedures being performed in the 2 hospitals.

  • Shuhei Yamada, Hajime Nakamura, Tomofumi Takenaka, Yohei Nakamura, Tom ...
    論文ID: oa.2024-0078
    発行日: 2024年
    [早期公開] 公開日: 2024/10/29
    ジャーナル オープンアクセス 早期公開

    Objective: Symptomatic vasospasm (SVS) affects the outcomes of patients with subarachnoid hemorrhage (SAH) and often requires endovascular treatment. Hyponatremia is a predictor of SVS; however, no guidelines have recommended an absolute serum sodium value for SVS prevention. This study aimed to identify factors that influence SVS in patients with low-grade SAH and determine a specific threshold of serum sodium level that predicts SVS.

    Methods: We conducted a multicenter, retrospective study of 216 patients with aneurysmal SAH grades I–III (World Federation of Neurological Societies scale). Patients were divided into the endovascular treatment-needed vasospasm (etVS) group (n = 29) and non-etVS group (n = 187). The minimum serum sodium level (minNa) was determined in the initial 2 weeks after SAH onset.

    Results: The minNa of the etVS group (median 132 mmol/L) was significantly lower compared to that of the non-etVS group (median 136 mmol/L) (p <0.001). The receiver operating characteristic curve revealed that a threshold minNa of 133 mmol/L predicted the development of etVS (sensitivity 0.797 and specificity 0.552), and the area under the curve was 0.703 (95% confidence interval [CI]: 0.591–0.815). The odds ratios for etVS in patients with a minNa ≤128 mmol/L and 129–132 mmol/L were 6.79 (95% CI: 2.24–20.51) and 2.96 (95% CI: 0.90–9.73), respectively, when compared to those with a minNa 133–136 mmol/L.

    Conclusion: Serum sodium levels were a predictor of etVS in patients with low-grade SAH. This is the first study to identify a threshold of serum sodium level for predicting etVS, aiding clinicians in setting a management goal for SVS prevention.

  • Takao Kojima, Takuya Maeda, Yuhei Ito, Haruhiko Kikuta, Masazumi Fujii
    論文ID: ra.2024-0073
    発行日: 2024年
    [早期公開] 公開日: 2024/10/29
    ジャーナル オープンアクセス 早期公開

    Onyx (Medtronic, Minneapolis, MN, USA) is a non-adhesive liquid embolic agent composed of an ethylene vinyl alcohol (EVOH) copolymer dissolved in dimethyl sulfoxide (DMSO). Onyx is explicitly designed for use in interventional neuroradiological procedures. Onyx’s unique formulation allows controlled delivery and solidification within the target vessel, providing durable occlusion of abnormal vascular structures such as arteriovenous malformations and dural arteriovenous fistulas. This report reviews the basic understanding of the use of Onyx in interventional neuroradiology. The hydrophilic properties of the agent facilitate its smooth delivery through microcatheters, ensuring precise navigation and deposition within vascular malformations under fluoroscopic guidance. When Onyx was injected into the target vessel, the vessel was embolized as the solvent (DMSO) diffused into the blood and EVOH precipitated to form a durable cast. Onyx liquid embolic agents substantially advance the endovascular treatment of intracranial vascular lesions.

  • Shanshan Cao, Duyi Zhang, Dayu Wu, Tianyi Li, Jialan Sun, Wei Zhu, Xue ...
    論文ID: cr.2024-0059
    発行日: 2024年
    [早期公開] 公開日: 2024/10/23
    ジャーナル オープンアクセス 早期公開

    Objective: Giant aneurysms of the cavernous segment of the internal carotid artery presenting as acute ischemic stroke (AIS) are rare and often misdiagnosed. Limited treatment experience further complicates management.

    Case Presentation: A 70-year-old female presented with acute right middle cerebral artery (MCA) occlusion due to a dislodged thrombus from a giant internal carotid aneurysm. Emergency multimodal brain imaging techniques, including CT, CTA, and DSA, were used to clarify the diagnosis. Given the giant aneurysm's interference, cross-circulation thrombectomy via the anterior communicating artery was performed to revascularize the occluded artery. The patient achieved a relatively good outcome due to timely reperfusion.

    Conclusion: This case highlights the importance of advanced imaging and innovative surgical techniques in managing complex cerebrovascular conditions, offering insights for future treatment of giant intracranial aneurysms with cerebral embolization.

  • Takao Koiso, Yoji Komatsu, Daisuke Watanabe, Hisayuki Hosoo, Masayuki ...
    論文ID: oa.2024-0054
    発行日: 2024年
    [早期公開] 公開日: 2024/10/19
    ジャーナル オープンアクセス 早期公開

    Objective: Middle cerebral artery (MCA) aneurysms are difficult to treat with coil embolization (CE) due to their location and shape, but the number of CE-treated MCA has gradually increased as treatment techniques have improved. However, the outcomes of CE for ruptured MCA aneurysms are poorly understood. This study aimed to evaluate the outcomes of CE for ruptured MCA aneurysms.

    Methods: We retrospectively analyzed the medical records of patients with aneurysmal subarachnoid hemorrhages (aSAH) that were treated with CE between 2013 and 2020, and compared the differences in outcomes depending on aneurysm location.

    Results: A total of 468 patients with aSAH were included: 39 patients had ruptured MCA aneurysms (group M), and 429 had ruptured aneurysms at other sites (group O). There were no significant differences between the background characteristics of the 2 groups. Also, there were no significant intergroup differences in occlusion status, the frequency of complications such as ischemia, hemorrhaging, rebleeding, retreatment, or the modified Rankin Scale score at discharge. However, intracerebral hemorrhage (ICH) removal was required significantly more frequently in group M than in group O (10.3% vs. 0.5%, p = 0.0006). By case-matching analysis, there were no significant differences in these outcomes. All MCA cases that needed removal had more than 36 ml of hematoma volume. Logistic regression analysis showed that the existence of ICH at onset was a poor prognostic factor for ruptured MCA aneurysms.

    Conclusion: CE for ruptured MCA aneurysms produced acceptable outcomes in selected cases. However, the indications for CE in patients with ICH should be carefully considered.

  • Naoya Kidani, Nobuyuki Hirotsune
    論文ID: ra.2024-0055
    発行日: 2024年
    [早期公開] 公開日: 2024/10/17
    ジャーナル オープンアクセス 早期公開

    Various types of embolic substances are used in endovascular therapy, and understanding their characteristics, including shape and kinetics, is essential for proper use. Cyanoacrylate is a typical liquid embolization agent that can be applied to many cerebral neurovascular lesions. It is injected as a mixture with ethiodized oil to provide radiopacity and regulate the polymerization rate. This review describes the characteristics, action mechanisms, techniques of use, and potential pitfalls of using cyanoacrylate-ethiodized oil mixtures for embolization.

  • Ryuta Yasuda, Naoki Toma, Seiji Hatazaki, Fuki Goto, Shota Ito, Yotaro ...
    論文ID: cr.2024-0068
    発行日: 2024年
    [早期公開] 公開日: 2024/10/08
    ジャーナル オープンアクセス 早期公開

    Objective: A Leonis Mova (LM; SB Kawasumi, Kanagawa, Japan), one of the steerable microcatheters, has a remote-controlled flexible catheter tip manipulated with a dial in the hand grip, which enables operators to overcome complicated branching in endovascular surgeries. We report a case of a pituitary tumor in which the LM worked effectively as a distal access catheter (DAC) in tumor embolization.

    Case Presentation: A female patient in her 70s complained of bitemporal hemianopsia, and an MRI revealed a pituitary tumor that appeared hypervascular. The right internal carotid artery angiography demonstrated a prominent stain from a tumor vessel derived from the meningohypophyseal trunk (MHT). Tumor embolization was scheduled before its removal due to the hypervascularity. In the tumor embolization, the tip of the LM was bent toward the orifice of the right MHT, through which a 1.3F–1.8F 155 cm microcatheter along with a 0.010-inch 200 cm microguidewire was advanced. Locking the LM tip provided good support for the microcatheter and the microguidewire to proceed to the tumor vessel. Successful tumor embolization was achieved with an injection of 0.21 ml of 12.5% n-butyl-cyanoacrylate. Thanks to the tumor embolization, gross total removal of the pituitary tumor was transshenoidally accomplished with the least blood loss. Histopathological diagnosis of pituicytoma was made, and the intraoperative blood loss of 100 ml seemed small for this histology. The patient recovered from the bitemporal hemianopsia and was discharged without a blood transfusion.

    Conclusion: This is the first report in which the LM was used and well worked in tumor embolization as a DAC.

  • Bumpei Yamasaki, Rei Goto, Hirotoshi Imamura, Nobuyuki Sakai
    論文ID: oa.2024-0057
    発行日: 2024年
    [早期公開] 公開日: 2024/10/05
    ジャーナル オープンアクセス 早期公開

    Objective: This study aimed to simulate patient transportation to a mechanical thrombectomy (MT)-capable hospital within 60 minutes, taking into account patient volume (demand side of healthcare) and hospital capacity to accept patients (supply side of healthcare).

    Methods: Simulations were conducted in Hyogo Prefecture, Japan. The estimates of the annual number of patients with stroke eligible for MT in 2020 were based on the incidence of stroke by age group and the percentage of patients with stroke indicated for MT in existing publications. Patients were then randomly placed on a 1 km2 mesh map. The patients were randomly generated 100 times using R software (version 4.1.2; R Foundation for Statistical Computing, Vienna, Austria). Hospitals were selected based on 2 criteria: (1) actual provision patterns (39 hospitals) and (2) consolidated patterns (12 hospitals). Simulations were performed using ArcGIS Pro (version 10.8; Esri, Redlands, CA, USA) and Network Analyst extension (Esri) in 3 cases: (1) number of patients estimated from the population in 2020 transported to hospitals that provided MT, (2) number of patients estimated based on the 2020 population transported to selected hospitals in the case of consolidation, and (3) number of patients estimated based on 2040’s projected population and transportation to the selected hospitals.

    Results: In Case 1, the estimated annual number of patients undergoing MT in 2020 was 976. The average number of patients undergoing MT and transported was 961, indicating that 98% (961/976) of the total generated patients could be transported within 60 min. In Case 2, the average number of patients undergoing MT and transported was 940, indicating that 96.3% (940/976) of the total patients could be transported within 60 min. In Case 3, the average number of patients undergoing MT and transported was 1184, showing that 95.1% (1184/1244) of the total generated patients could be transported within 60 min. A few patients in rural areas and remote islands required longer transport times.

    Conclusion: The simulations showed that patient estimates from the incidence of cerebral infarction by age group and the percentage of patients with stroke indicated for MT were similar to the actual values. The simulation was closed to reality when both the supply and demand sides of healthcare were considered. Thus, this simulation study informs future healthcare policy by demonstrating the geographic distribution of human and capital resources and potential cost reduction through consolidation, taking into account demographic changes.

  • Hideaki Shigematsu, Azusa Sunaga, Takuya Yonemochi, Akihiro Hirayama, ...
    論文ID: oa.2024-0050
    発行日: 2024年
    [早期公開] 公開日: 2024/10/04
    ジャーナル オープンアクセス 早期公開

    Objective: Prehension of the position of the microcatheter tip under fluoroscopy during cerebral aneurysm embolization is critical to prevent intraoperative rupture of the aneurysm, even if the first marker at the tip is obscured by coils in the aneurysm. This study presents our initial experience with a sub-marker catheter, which includes an additional marker positioned 5 mm from the tip, designed to facilitate accurate positioning of the microcatheter tip.

    Methods: We analyzed cases of cerebral aneurysms treated with sub-marker catheters at our hospital from July 2022 to September 2023. Single catheter embolization served as the primary treatment option, with balloon-assisted or stent-assisted techniques utilized only when necessary.

    Results: During the study period, 18 patients with cerebral aneurysms were treated using sub-marker catheters. The median age of these patients was 65 years, comprising 8 men and 10 women. The aneurysms had a median maximum diameter of 6.2 mm, ranging from 5.0 to 16.8 mm. Among the 18 treated patients, 14 had unruptured aneurysms and 4 had ruptured aneurysms. Treatment methods included single catheter embolization in 10 patients, double catheter embolization in 3, stent-assisted embolization in 3, balloon-assisted embolization in 1, and flow diverter placement combined with coil embolization in 1. The sub-marker was consistently visible under fluoroscopy, aiding the precise positioning of the microcatheter tip without interference from the coils. No complications occurred, and successful embolization was achieved in all cases.

    Conclusion: The sub-marker catheter appears valuable for safely performing aneurysm embolization.

  • Satoshi Koizumi, Motoyuki Umekawa, Shigeta Fujitani, Hideaki Ono, Sato ...
    論文ID: ra.2024-0062
    発行日: 2024年
    [早期公開] 公開日: 2024/10/01
    ジャーナル オープンアクセス 早期公開

    This review discusses the use of N-butyl cyanoacrylate (NBCA) in various neuroendovascular treatments. Despite the increase in the ONYX, NBCA continues to have significant usage. It is particularly useful for the treatment of arteriovenous malformations (AVM) and dural arteriovenous fistulas (dAVFs). Comparative studies have suggested that ONYX and NBCA are equally effective and safe for the treatment of AVM. However, the choice between the two depends on specific situations, such as the characteristics of the feeding arteries. NBCA is recommended for tortuous feeders, high-flow fistulous feeders, and feeders with a short margin of reflux, owing to the procedural risks posed by ONYX. The use of NBCA is also prominent in dAVF embolization. While achieving total occlusion solely with NBCA can be challenging, NBCA adheres to the vessel wall and encourages thrombus formation, aiding in fistula obliteration. In addition to AVM and dAVF, NBCA is used to treat chronic subdural hematoma and craniofacial vascular injuries. Embolization using NBCA is beneficial because of its deep penetration into the target tissue. For craniofacial injuries, NBCA embolization provides secure hemostasis within a short time. Neuroendovascular physicians should understand the characteristics of NBCA as a liquid embolic material and have expertise in the technical aspects of NBCA embolization, even in the ONYX era.

  • Kenichi Sato, Yasushi Matsumoto, Masayuki Ezura, Hidenori Endo
    論文ID: ra.2024-0049
    発行日: 2024年
    [早期公開] 公開日: 2024/09/27
    ジャーナル オープンアクセス 早期公開

    Objective: The authors aimed for a systematic review to clarify the current role of transarterial embolization (TAE) in the management of brain arteriovenous malformations (BAVMs).

    Methods: A search was conducted on PubMed, using the following terms; “brain arteriovenous malformation,” “cerebral arteriovenous malformation,” “endovascular treatment,” and “transarterial embolization.” Studies reporting the efficacy and safety of endovascular treatment for BAVMs, performed either as a standalone treatment or in conjunction with surgery or radiosurgery, were included. The final search was conducted in December 2023. Only articles written in English were reviewed. The references of publications of interest were also screened. Studies on transvenous embolization were excluded. More than 100 articles on the treatment of BAVMs were reviewed.

    Results: Advances in endovascular techniques and devices have enabled TAE as a treatment modality for BAVMs, to achieve higher embolization rates. Thus, curative TAE for some BAVMs with suitable angioarchitecture has become possible. The efficacy of presurgical TAE in the treatment of low Spetzler-Martin grade BAVMs is limited; however, TAE is effective for intermediate grade BAVMs. Several reports using propensity-matched analyses reevaluated the therapeutic efficacy of pre-/post-radiosurgical TAE for BAVMs with radiosurgery-resistant lesions such as large nidus, fistulous components, and associated aneurysms. The complication rate of TAEs as a treatment modality for BAVMs is approximately 10%, and hemorrhagic complications occur in approximately 5% of cases. Despite recent advances, substantial improvements have not been observed in the morbidity and mortality associated with TAEs for the treatment of BAVMs.

    Conclusion: TAE for the treatment of BAVMs is primarily performed in an adjuvant manner; however, recent advances have made standalone embolization possible. A multidisciplinary team should evaluate each case independently. Furthermore, as per recent studies, inclusive of meta-analyses, the efficacy and safety of TAEs for the treatment of BAVMs have not been elucidated. Thus, the manifestations and characteristics of BAVMs, in addition to the objective of performing a TAE, should be deliberated carefully before the endovascular procedure, to avoid complications.

  • Nobuyuki Mitsui, Hajime Wada, Masato Saito, Hirotaka Sato, Manabu Kino ...
    論文ID: oa.2024-0042
    発行日: 2024年
    [早期公開] 公開日: 2024/09/21
    ジャーナル オープンアクセス 早期公開

    Objective: Contrast-induced encephalopathy (CIE) is a rare but severe complication that can occur following intravascular treatment of intracranial vascular disease. Although CIE is considered a transient neurological disorder, its natural history, pathophysiology, and risk factors are poorly understood. Contrast leakage (CL) is a more frequently observed adverse event than CIE and can lead to CIE. This retrospective study aimed to elucidate the clinical characteristics of CL and CIE and identify the risk factors for each.

    Methods: We retrospectively reviewed the medical records of 61 patients with unruptured intracranial aneurysms who were treated at our institution between January 2019 and May 2023. Risk factors for CIE and CL were identified by Fisher’s exact test for univariate analysis of categorical variables and by unpaired t-test for continuous variables. One-way analysis of variance (ANOVA) was conducted, followed by the Tukey-Kramer test for multiple comparisons.

    Results: Of the 61 patients, 22 (36%) had CL and 4 (6%) had CIE. Among the clinical characteristics analyzed, older age (p = 0.031), larger aneurysm (p = 0.003), lower serum creatinine (p = 0.026), and use of a distal access catheter (p = 0.030) were significant risk factors for CL. CIE occurred only in CL-positive patients (p = 0.014). Of the 4 patients with CIE, neurological symptoms improved within 3 days in 3 patients, and neurological deficit persisted in 1 patient.

    Conclusion: Older age, larger aneurysm, lower serum creatinine, and use of a distal access catheter are risk factors for developing CL, and female sex and greater volume of contrast medium are potential risk factors. No risk factors for developing CIE from CL were identified.

  • Katsuya Saito, Go Ikeda, Yoshimitsu Akutsu, Yusuke Morinaga, Shunsuke ...
    論文ID: cr.2024-0015
    発行日: 2024年
    [早期公開] 公開日: 2024/09/19
    ジャーナル オープンアクセス 早期公開

    Objective: We describe two cases of myelopathy onset due to intracranial dural arteriovenous fistulas (DAVFs) and present a literature review.

    Case Presentation: (Case 1) A 44-year-old man with subacute onset myelopathy underwent an MRI and DSA. MRI showed T2-hyperintensity from the medulla oblongata to the cervical spinal cord with vascular flow voids, suggestive of a spinal DAVF. Unexpectedly, cerebral angiography revealed a tentorial DAVF. (Case 2) A 47-year-old man with progressive myelopathy underwent a head and spinal MRI. Head MRI and MRA were considered to be normal. Spinal MRI revealed T2-hyperintensity in the cervical spinal cord without obvious vascular flow voids around the spinal cord. Contrast-enhanced MRI showed a patchy gadolinium enhancement in the same spinal cord region with the enhancement of perimedullary vessels. Although myelitis was initially suspected, subsequently spinal DAVF was suspected because cervical CTA revealed abnormal spinal venous drainage. Unexpectedly, cerebral angiography identified a foramen magnum DAVF.

    Conclusion: Regarding unexplained cervical myelopathy, even the absence of spinal cord surface vascular flow voids cannot necessarily exclude venous congestive myelopathy due to the DAVFs. In such cases, the contrast-enhanced MRI and cervical CTA are useful for visualizing abnormal vessels around the brain stem and the cervical spine. Especially, the co-presence of the abnormal vessels around the brain stem can suggest the intracranial DAVFs. Not only spinal DAVFs but also intracranial DAVFs should be considered as the differential diagnoses for venous congestive cervical myelopathy, in which cases cerebral angiography including carotid angiography is essential.

  • Yoshiro Ito, Yuji Matsumaru, Hisayuki Hosoo, Shun Tanaka, Kota Araki, ...
    論文ID: oa.2024-0041
    発行日: 2024年
    [早期公開] 公開日: 2024/09/14
    ジャーナル オープンアクセス 早期公開

    Objective: Although embolization of cerebral arteriovenous malformations (AVM) is widely performed as an adjunctive therapy before microsurgery or radiosurgery, there is no high-level evidence to ascertain its effectiveness. However, the technology for endovascular devices has improved. Therefore, this study aimed to identify the chronological changes in AVM embolization due to advances in endovascular treatment devices.

    Methods: This retrospective study included 24 patients who underwent 31 embolization procedures between January 2018 and August 2023. Embolization plus microsurgery, embolization plus radiosurgery, and embolization alone were performed in 15 (62.5%) patients and 21 embolization procedures, 2 (8.3%) patients and 2 procedures, and 7 (29.2%) patients and 8 procedures, respectively. We assessed chronological changes in endovascular treatment devices and evaluated clinical outcomes (ideal position of microcatheter, vessel perforations, symptomatic complications) from January 2018 to December 2020 and from January 2021 to August 2023 based on the chronological changes in endovascular treatment devices.

    Results: Intermediate catheters were employed in 29 (93.5%) procedures. Brands of intermediate catheters and microcatheters significantly changed around 2021. No differences were observed in the embolic materials. The ideal position of the microcatheter was achieved significantly more in 2021–2023 than in 2018–2020 (72.1% vs. 48.4%, p = 0.04). Vessel perforation by microcatheters in 2018–2020 and 2021–2023 occurred in 3 (18.8%) and 1 (6.7%) procedures (p = 0.32), respectively. Symptomatic complications in 2018–2020 and 2021–2023 occurred in 3 (18.8%) and 0 (p = 0.08) procedures, respectively. Complete obliteration was achieved in 18 of 24 patients (75.0%). Favorable clinical outcomes (modified Rankin Scale score 0–2) were observed in 20 of 24 (83.3%) patients at the final follow-up.

    Conclusion: The advancement in endovascular devices for AVM has enabled effective and safe embolization, potentially enhancing the outcomes of microsurgical interventions.

  • Michihiro Tanaka
    論文ID: ra.2024-0037
    発行日: 2024年
    [早期公開] 公開日: 2024/08/06
    ジャーナル オープンアクセス 早期公開

    Brain arteriovenous malformations (AVMs) are intricate networks of blood vessels in which arteries connect directly to veins, bypassing the capillary system. This aberration can lead to serious neurological manifestations, including seizures, headaches, and hemorrhagic strokes. The embryonic development of AVMs implicates possible disruptions in arteriovenous differentiation during angiogenesis, improper regression of the primary capillary plexus, or the retention of fetal vasculature as contributing factors. Additionally, genetic mutations and environmental influences during pregnancy may facilitate AVM formation, with identified mutations in genes such as endoglin, activin receptor-like kinase 1, SMAD family member 4, and RAS p21 protein activator 1 disrupting vascular development. Such mutations are associated with conditions like hereditary hemorrhagic telangiectasia and capillary malformation-arteriovenous malformation syndrome, thus highlighting the essential role of genetic counseling in AVM management. This review underscores the importance of a deep comprehension of the embryological and genetic foundations of AVMs to refine diagnostic, therapeutic, and prognostic approaches. The paper advocates for advanced research on intervention strategies and emphasizes the significance of a genetics-focused approach in the clinical management of AVMs.

  • Masaomi Koyanagi, Masanori Goto, Junichi Takeda, Ryu Fukumitsu, Tadash ...
    論文ID: ra.2024-0035
    発行日: 2024年
    [早期公開] 公開日: 2024/07/01
    ジャーナル オープンアクセス 早期公開

    Brain arteriovenous malformations (bAVMs) are uncommon vascular lesions found in young individuals exhibiting diverse clinical manifestations ranging from asymptomatic to spontaneous intracranial hemorrhage, seizures, or headaches. Despite improvements in endovascular tools and methods, standalone transarterial embolization seldom achieves success rates surpassing 50%, even when employing ethylene vinyl alcohol copolymers. Transvenous embolization (TVE) emerges as a promising option, especially for bAVMs situated distally or inaccessible through arterial routes. Despite the possibility of achieving high angiographic cure rates, concerns regarding hemorrhagic complications persist, limiting its adoption. This review article outlines the indications and methodology of TVE, discusses complications, and highlights the essential expertise needed for the safe execution of TVE along with strategies to mitigate associated risks. Clinical results reveal promising outcomes in terms of obliteration rates and favorable neurological results, although challenges persist, particularly regarding device accessibility and risk management. Despite these challenges, TVE remains a valuable alternative for managing bAVMs, particularly for cases resistant to surgical intervention, emphasizing the significance of careful patient selection and procedural expertise.

  • Hirofumi Matsubara, Yusuke Egashira, Yukiko Enomoto
    論文ID: ra.2024-0016
    発行日: 2024年
    [早期公開] 公開日: 2024/06/22
    ジャーナル オープンアクセス 早期公開

    Thromboembolism is one of the main causes of severe complications in the endovascular treatment of cerebral aneurysms, and antiplatelet therapy (APT) is necessary to prevent such complications. Conversely, prolonged APT has the potential risk of hemorrhagic complications; therefore, the timing of dose reduction or discontinuation is an important aspect of periprocedural APT. However, no clinical evidence of an optimal regimen of APT for cerebral aneurysms exists, and the selection, dosage, duration, or combination of antiplatelets has been dependent on physicians for unruptured or ruptured cerebral aneurysms. Many reports have shown that preoperative APT can reduce ischemic complications without increasing hemorrhagic complications, and some reports have shown that the P2Y12 reaction unit (PRU) value measured using the VerifyNow (Werfen, Barcelona, Spain) system is associated with periprocedural ischemic and hemorrhagic complications. Appropriate dose and duration management adjustments based on the platelet reactivity test, aneurysm morphology, treatment, and patient background may contribute to good outcomes. Although accumulating evidence exists regarding the efficacy of preoperative APT, there is no evidence regarding the optimal duration or discontinuation of APT.

  • Takahiro Ota
    論文ID: ra.2024-0008
    発行日: 2024年
    [早期公開] 公開日: 2024/05/21
    ジャーナル オープンアクセス 早期公開

    Brain arteriovenous malformations (bAVMs) are associated with a high risk of intracerebral hemorrhage, which causes severe complications in patients. Although the genetic factors leading to hereditary bAVMs have been extensively investigated, their pathogenesis are still under study. This review examines updated data on the molecular and genetic aspects of bAVMs, the architecture of microvasculature, the roles of angiogenic factors, and signaling pathways. The compiled information may help us understand the pathogenesis of both sporadic and hereditary bAVMs and develop appropriate preemptive treatment approaches.

  • Ichiro Nakagawa, Masashi Kotsugi, Shohei Yokoyama, Ryosuke Maeoka, Hir ...
    論文ID: ra.2024-0014
    発行日: 2024年
    [早期公開] 公開日: 2024/04/16
    ジャーナル オープンアクセス 早期公開

    Optimal platelet inhibition is critical in patients with carotid and intracranial artery stenosis undergoing carotid artery stenting (CAS) and intracranial artery stenting (ICS). Many reports have highlighted the importance of dual antiplatelet therapy (DAPT) in reducing adverse neurological outcomes without a significant increase in bleeding complications during CAS. DAPT has commonly used CAS and ICS, typically with aspirin and clopidogrel, but clopidogrel resistance occurs in approximately 20% of Japanese and other Asian populations. One solution to clopidogrel resistance is using adjunctive cilostazol to suppress the frequency of stroke events and in-stent restenosis after CAS. Other antiplatelet agents such as prasugrel, ticagrelor, cangrelor, and glycoprotein (GP) IIb/IIIa inhibitors are under investigation. The duration of DAPT after CAS remains controversial, as a longer duration of DAPT after CAS is associated with lower rates of readmission for stroke, but increased risk of hemorrhagic complications. Regarding antithrombotic therapy in CAS with concomitant atrial fibrillation, the use of direct oral anticoagulants plus a P2Y12 inhibitor may be suggested for the optimal safety and efficacy of antithrombotic management. For emergent CAS in acute ischemic stroke (AIS), intraprocedural DAPT loading and GP IIb/IIIa inhibitors, as necessary, may improve stent patency without increasing the risk of intracranial hemorrhage. In ICS, aggressive antiplatelet therapy based on an assessment of platelet aggregation is also important to improve clinical outcomes. In addition, rescue stenting for AIS caused by intracranial atherosclerotic stenosis-related large vessel occlusion is gaining attention. GP IIb/IIIa inhibitors have shown promise, but are not approved in Japan. In conclusion, DAPT is essential for the perioperative management of CAS and ICS. Specific perioperative antithrombotic management remains unclear, but the potential benefits of antithrombotic agents must be weighed against the corresponding increased risk of bleeding complications.

  • Masatoshi Koga
    論文ID: ra.2024-0001
    発行日: 2024年
    [早期公開] 公開日: 2024/03/13
    ジャーナル オープンアクセス 早期公開

    Antithrombotic therapy plays a crucial role in secondary prevention following ischemic stroke from the acute phase. Numerous trials, along with a meta-analysis, contributed to establishing aspirin as the primary medication for secondary stroke prevention. According to the Cochrane Database of Systematic Review 2022, initiating antiplatelet therapy with aspirin at a dose of 160 mg to 300 mg daily within 48 hours of stroke onset reduces the risk of death or dependency at the end of follow-up. Other antiplatelet drugs, such as clopidogrel, cilostazol, prasugrel, and intravenous ozagrel sodium, are also available within the Japanese Health Care Insurance System. Two pivotal trials from the 2010s underscored the effectiveness and safety of dual antiplatelet therapy (DAPT) using aspirin and clopidogrel, administered for 21 days to 3 months following acute ischemic stroke or transient ischemic attack. However, the extension of DAPT with aspirin and clopidogrel beyond 3 months may result in substantial bleeding risks. Although prasugrel offers a rapid, potent, and consistent inhibition of platelet aggregation and can be used in place of clopidogrel, there is a lack of substantial real-world clinical data on its use in acute ischemic stroke. It is important to recognize that antiplatelet drugs might not be beneficial and could even increase the risk of hemorrhagic events in cardioembolic stroke. In cases of ischemic stroke with nonvalvular atrial fibrillation, direct oral anticoagulants are the primary choice if applicable. Warfarin continues to be the anticoagulant of choice for secondary stroke prevention in patients with mechanical valve replacements. In patients who have undergone intravenous thrombolysis, antithrombotic therapy is generally delayed for up to 24 hours, although there are no definitive guidelines for the period during and immediately after mechanical thrombectomy. This review provides an overview of the current status of antithrombotic therapy for acute ischemic stroke.

  • Naoki Akioka, Naoya Kuwayama, Satoshi Kuroda
    論文ID: ra.2023-0034
    発行日: 2023年
    [早期公開] 公開日: 2023/12/23
    ジャーナル オープンアクセス 早期公開

    The sphenoid wing dural arteriovenous fistulas (DAVFs) are clinically rare. They often present as non-sinus-type arteriovenous fistulas (AVFs) and may be associated with focal neurological deficits, intracranial venous hypertension, and intracranial hemorrhage. These cases are classified as lesser or greater sphenoid wing lesions. We searched the PubMed databases for studies evaluating the clinical presentation, surgical treatment, and endovascular treatment of these lesions and analyzed 37 cases from 22 papers. A total of 17 cases had lesser sphenoid wing AVFs, and the localization of the shunts could be divided into the sinus of the lesser sphenoid wing (SLSW) or the superficial middle cerebral vein (SMCV). Most SLSW AVFs drained into the cavernous sinus, but two cases drained directly into the deep middle cerebral vein via a bridging vein. All cases with shunts directly into the SMCV had reflux into the SMCV with varices. A total of 20 cases had shunts in the greater sphenoid wing, and the localization of the shunts varied, with shunt localization, and venous return morphology dependent on variations in middle fossa venous return. Most cases had shunts in the sphenobasal vein near the foramen ovale. However, some cases had shunts in the superior ophthalmic vein, sphenopetrosal vein, and laterocavernous sinus. Many were associated with cortical venous reflux. These lesions have been treated by surgical ligation of the drainage vein and transarterial or transvenous embolization. Recently, embolization has become the standard treatment for DAVFs due to advances in endovascular techniques. This paper reviewed and discussed the angioarchitecture, clinical presentation, and treatment of these lesions to clarify the characteristics of sphenoid wing DAVFs.

  • Yoichi Morofuji, Minoru Morikawa, Nobutaka Horie, Yuki Matsunaga, Tsuy ...
    論文ID: ra.2023-0023
    発行日: 2023年
    [早期公開] 公開日: 2023/09/05
    ジャーナル オープンアクセス 早期公開

    The clinical manifestations of dural arteriovenous fistulas (dAVFs) are highly variable and dependent on the hemodynamic properties and location of the fistula. The locations of the fistula are numerous and include the cavernous sinus, transverse–sigmoid sinus, superior sagittal sinus, inferior and superior petrosal sinuses, anterior condylar confluence, tentorium, anterior cranial fossa, middle fossa, foramen magnum, cranio-cervical junction, convexity, and spinal cord. These dAVFs can be divided into two types, “sinus type” and “non-sinus type,” based on their communication with dural shunts and cerebral veins. The sinus type involves direct communication between the arterial dural branch and one dural sinus, sometimes leading to recruitment of cortical veins. On the other hand, the non-sinus type is embedded into the dura, with the drainage always involving a cerebral vein and no communication with any sinus. Treatment options for these types of dAVFs differ; sinus-type dAVFs require normally sinus obliteration and occlusion of recruited veins, while non-sinus-type dAVFs require embolization of the drainage vein. Accurately classifying the type of fistula, sinus type or non-sinus type, is critical for developing a proper treatment plan. This review describes clinical characteristics and treatment of those non-sinus-type dAVFs involving unusual locations with illustrative cases.

  • Masafumi Hiramatsu, Tomohiko Ozaki, Rie Aoki, Shinri Oda, Jun Haruma, ...
    論文ID: ra.2023-0019
    発行日: 2023年
    [早期公開] 公開日: 2023/07/12
    ジャーナル オープンアクセス 早期公開

    Dural arteriovenous fistula (dAVF) of the foramen magnum (FM) region is rare. Moreover, the terminology of dAVF is very confusing in this region. In the narrow sense, the FM dAVF is the non-sinus-type dAVF with direct venous reflux to the medulla oblongata or spinal cord via the bridging veins (BVs) of the FM. Previous literature was systematically reviewed to investigate the clinical characteristics, angioarchitecture, and effective treatment of the FM dAVF. From the literature review, almost all the feeders of FM dAVF were dural branches. Spinal pial arteries were rarely involved as the feeder. All lesions had venous reflux to the medulla oblongata via medullary BVs. The FM dAVF is characterized by a significant male predominance and a high incidence of aggressive symptoms. The most common symptom is congestive myelopathy, followed by hemorrhage. The FM dAVF differs from the craniocervical junction (CCJ) arteriovenous fistula (AVF) and is similar to the thoracolumbar spinal dAVF. Direct surgery for the FM dAVF is effective and safe. Endovascular treatment for the FM dAVF may be more effective and has lower complication rates than that for the CCJ AVF.

  • Ichiro Nakagawa, Masashi Kotsugi, Shohei Yokoyama, Ryosuke Maeoka, Tom ...
    論文ID: ra.2023-0018
    発行日: 2023年
    [早期公開] 公開日: 2023/05/26
    ジャーナル オープンアクセス 早期公開

    Anterior cranial fossa (ACF) dural arteriovenous fistula (DAVF) is a rare lesion among cerebral DAVFs. This lesion shows significant bleeding risk because of the angioarchitecture, involving direct leptomeningeal retrograde venous drainage, as a nonsinus-type DAVF. Over the years, direct surgery has been considered the primary treatment for ACF DAVF, offering favorable clinical outcomes compared to a low complete obliteration rate with endovascular treatment and the relatively high risk of blindness due to central retinal artery occlusion with transophthalmic artery embolization. In recent years, however, significant improvements in DSA and 3D reconstruction imaging quality have allowed a much more precise understanding of the angioarchitecture of the shunt and vascular access route. In addition, advances in endovascular devices, including catheters and embolic materials, have facilitated microcatheter navigation into more distal vessels and more reliable closure of the fistulous point. Supported by such technological innovations, endovascular approaches to the treatment of ACF DAVF have been becoming successful first-line treatments. This article reviews the evolution of treatment strategies and the current status of endovascular treatment for ACF DAVF, with a particular focus on transarterial embolization.

feedback
Top