A new very-small-bore Simmons guiding sheath for transradial neurointervention: Technical note and initial experience.

Transradial access during neurointerventions has increased in popularity because of reduced complications and patient preference. Nevertheless, transradial cannulation into the left common carotid artery can be difficult technically because of the lack of catheter support in the aortic arch. Furthermore, the use of large sheaths can increase the risk of complications at the access site. Here, we developed a new very-small-bore transradial system using a 3F Simmons guiding sheath, to increase the procedural success rate and minimize access-site complications. This system can represent a valuable treatment option for neurointerventions and has the potential to expand the indications for transradial access.

Intraspinal canal platform system for coil embolization of anterior spinal artery aneurysm associated with spinal cord arteriovenous malformation: a case report and literature review.

BACKGROUND: The prognosis for spinal artery aneurysms associated with spinal cord arteriovenous malformations (AVMs) is poor because of the high rupture rate of aneurysms. However, endovascular treatment remains technically difficult because the catheter system must be constructed via the small-caliber anterior spinal artery (ASA) or posterior spinal artery (PSA), which feeds functionally eloquent spinal cord. A 2.6F Carnelian HF-S microcatheter (Tokai Medical Products, Aichi, Japan) has been specifically designed to assist a 1.6F Carnelian MARVEL S microcatheter (Tokai Medical Products) as a small-profile 'platform catheter' close to the target lesion. Here we present a prenidal ASA aneurysm treated using a 2.6F Carnelian HF-S microcatheter as an intraspinal canal platform catheter and review related literature. CASE PRESENTATION: A 50-year-old man presented with a subarachnoid haemorrhage due to cervical spinal cord AVM. Diagnostic vertebral angiography revealed the AVM supplied by the PSA originated from the right C2 segmental artery and ASA arising from the right V4 segment. Superselective angiography for each feeder was achieved through a 2.6F Carnelian HF-S microcatheter, and a prenidal ASA aneurysm was diagnosed, which was clinically consistent with haemorrhagic origin. A 1.6F Carnelian MARVEL S microcatheter was cannulated into the aneurysm through the 2.6F Carnelian HF-S microcatheter positioned at the ASA. The aneurysm coiling was successfully performed without system instability or periprocedural complications. CONCLUSIONS: Only a few cases have described endovascular treatment for spinal artery aneurysms. To date, no reports have been published regarding the use of an intraspinal canal platform catheter to treat spinal artery aneurysms. A 2.6F Carnelian HF-S microcatheter served as a useful intraspinal canal platform catheter for coil embolization of the ASA aneurysm. This system can provide excellent accessibility and controllability for endovascular treatment of spinal artery lesions.

Real-time angiography in endovascular revascularization of intracranial atherosclerotic internal carotid artery stenosis under proximal balloon protection: "Retrograde suction-injection" technique and literature review.

Intracranial angioplasty/stenting is a treatment option for patients with symptomatic intracranial atherosclerotic disease refractory to aggressive medical treatment. However, it carries a risk of procedure-related embolism as well as reperfusion hemorrhage and in-stent thrombosis. We have devised a new embolic protection system which can achieve both total ipsilateral internal carotid artery (ICA) embolic protection and real-time visualization of the target lesion during endovascular revascularization of intracranial atherosclerotic disease below the carotid T junction. Herein, we describe a case of medically refractory symptomatic intracranial atherosclerotic ICA stenosis successfully treated with this method.

Contralateral Transradial Access for Coil Embolization of Distal Anterior Cerebral Artery Aneurysm Associated With a Steep Ipsilateral A1-A2 Angle.

OBJECTIVE: Endovascular treatment of distal anterior cerebral artery aneurysms is commonly addressed via the ipsilateral A1 segment of the anterior cerebral artery. However, when the parent pericallosal artery has a sharp ipsilateral A1-A2 angle, catheterization through the ipsilateral A1 segment can potentially result in vessel injury, catheter kinking, and/or compromised/stagnant anterior cerebral artery flow. Here, we present a case of a distal anterior cerebral artery aneurysm associated with a steep ipsilateral A1-A2 angle treated with contralateral transradial coil embolization. CASE PRESENTATION: A 91-year-old woman presented with a ruptured left distal anterior cerebral artery aneurysm at the A3 segment. The parent pericallosal artery had a steep ipsilateral A1-A2 angle. To safely achieve coil embolization of the aneurysm, a contralateral transradial system via the right A1 segment was employed. Although a secondary ipsilateral transradial system was required for contrast injection, aneurysm obliteration was successfully achieved without vessel injury or system instability. CONCLUSION: The A1-A2 angle can be a key anatomical factor in the endovascular treatment of distal anterior cerebral artery aneurysms. The contralateral transradial system is a useful treatment option for distal anterior cerebral artery aneurysms associated with sharp ipsilateral A1-A2 angles. However, if the distal anterior cerebral artery aneurysm cannot be clearly visualized through the contralateral system, an ipsilateral system will be required for contrast injection.

Transradial quadraxial system for coil embolization of distal anterior cerebral artery aneurysms: A radial-first center case series and literature review.

PURPOSE: Endovascular treatment is technically challenging as distal anterior cerebral artery (DACA) aneurysms have distal location, small-caliber parent artery, and small size/wide neck. This study evaluated the feasibility and safety of the transradial approach (TRA) with a radial-specific neurointerventional guiding sheath as the first-line technique for DACA aneurysms. METHODS: We retrospectively analyzed an institutional database of consecutive patients with DACA aneurysm who underwent coil embolization using TRA. Ten consecutive patients were included in this study. After the radial-specific 6F Simmons guiding sheath (0.088″ inner diameter) was completely engaged into the target common carotid artery, a quadraxial system (6F Simmons guiding sheath/6F intermediate catheter/3.2F intermediate catheter/single microcatheter) was used for embolization. Then, we assessed for procedural success, angiographic outcomes, and procedure-related or vascular access site complications. RESULTS: Embolization procedures were conducted using simple coiling in eight and stent-assisted coiling with the trans-cell approach in two patients. The embolization procedure was successful in all patients (n = 10). Moreover, none presented with catheter kinking, parent artery flow stagnation, or system instability during the procedure. Immediate postprocedural angiography revealed complete obliteration in six and residual neck in four patients. Then, eight patients underwent follow-up angiography at a mean of 7.1 months, and none developed recanalization or required retreatment. The postprocedural course was uneventful, and there were no complications. CONCLUSION: The transradial quadraxial system had the ability to achieve sufficient stability and kink resistance in DACA aneurysm embolization. Thus, this method was feasible and safe and had a high success rate.

Pediatric Case of Life-Threatening Stroke Caused by Reversible Cerebral Vasoconstriction Syndrome with Spontaneous Cervical Internal Carotid Artery Vasospasm: A Case Report.

Pediatric reversible cerebral vasoconstriction syndrome (RCVS) and spontaneous cervical internal carotid artery (ICA) vasospasm are rare conditions; the former is commonly associated with a favorable prognosis. A healthy 13-year-old girl presented with thunderclap headache, followed by left hemiparesis, during a curling match. Six days after onset, left hemiparesis worsened to hemiplegia. Magnetic resonance imaging showed progressive cerebral infarction caused by severe right middle cerebral artery and cervical ICA stenosis. She became comatose because of impending uncal herniation. Emergent surgical decompression was performed. Then, 59 days after onset, her multiple stenoses improved, which was consistent with RCVS concomitant with spontaneous cervical ICA vasospasm. This is the first case of RCVS that concurrently developed spontaneous cervical ICA vasospasm. The patient developed life-threatening stroke due to the hemodynamic impairment of the affected intracranial and cervical arteries. Spontaneous extracranial supra-aortic artery vasospasm can be a poor prognostic predictor of RCVS.

T-Configuration Stent Placement for Carotid Bifurcation Stenosis Co-Existing with Ipsilateral Intracranial Stenosis: A Case Report and Literature Review.

In patients with carotid bifurcation stenosis co-existing with ipsilateral intracranial artery stenosis, combined treatment with carotid artery stenting (CAS)/carotid endarterectomy (CEA) and extracranial-to- intracranial (EC-IC) bypass can be a useful option to prevent future ischemic stroke events. EC-IC bypass requires a sufficient antegrade flow in the ipsilateral external carotid artery. However, standard CAS/CEA occasionally lead to external carotid artery occlusion. Herein, we present a case of successful one-stage endovascular revascularization of both the antegrade internal and external carotid artery flow using the carotid T-stent technique for carotid bifurcation stenosis co-existing with ipsilateral middle cerebral artery stenosis.

Novel Orange Color Pigments Based on La3LiMnO7.

La3LiMn1-xTixO7 (0 ≤ x ≤ 0.05) samples were synthesized by a solid-state reaction method, and a single-phase form was observed for the samples in the range of x ≤ 0.03. Crystal structure, optical properties, and color of the La3LiMn1-xTixO7 (0 ≤ x ≤ 0.03) samples were characterized. Strong optical absorption was observed at a wavelength between 400 and 550 nm, and a shoulder absorption peak also appeared around 690 nm in all samples; orange colors were also exhibited. Among the samples synthesized, the most brilliant orange color was obtained at La3LiMn0.97Ti0.03O7. The redness (a*) and yellowness (b*) values of this pigment were higher than those of the commercially available orange pigments. Therefore, the orange color of this pigment is brighter than those of the commercial products. Since the La3LiMn0.97Ti0.03O pigment is composed of non-toxic elements, it could be a new environmentally friendly inorganic orange pigment.

Wrap-clipping as a rescue surgical technique for vessel perforation due to stent strut: a technical note.

BACKGROUND: Arterial injury related to stent strut is rare during stent-assisted coil embolization. METHOD: The patient underwent stent-assisted coil embolization for a right middle cerebral artery aneurysm. At this time, the parent arterial injury at M1 portion of the middle cerebral artery resulted in subarachnoid hemorrhage. The arterial penetration caused by the stent strut was repaired with wrap-clipping. RESULTS: Postoperative angiograms demonstrated the complete obliteration of the arterial injury. The patient was discharged without neurological deficits. Neither recurrence nor stenosis was observed after surgery. CONCLUSIONS: Wrap-clipping is a useful procedure to repair the arterial injury due to the stent strut.

Calcified ectopic TSH-secreting pituitary adenoma mimicking craniopharyngioma: a rare case report and literature review.

Among pituitary adenomas, which are relatively common brain tumors, elements of ectopic, thyroid-stimulating hormone (TSH) secretion, and intratumoral calcification are unusual. Here, we present an extremely rare case of a calcified ectopic TSH-secreting pituitary adenoma arising from the pars tuberalis mimicking craniopharyngioma based on neuroimaging findings. To our knowledge, this is the first case report of calcified ectopic TSH-secreting pituitary adenoma without symptoms of excessive thyroid hormone secretion.

Forearm access for carotid artery stenting using the dual protection of flow reversal and distal filter: Trans-forearm dual protection technique.

BACKGROUND: Although transfemoral carotid artery stenting (CAS) is widely performed for carotid stenosis, serious or even fatal complications such as embolic and access site complications can still occur. We devised a novel dual protection system with continuous flow reversal to the cephalic vein of the forearm in transradial CAS, referred to as the "trans-forearm dual protection" technique. METHODS: A 75-year-old man with a diagnosis of symptomatic left cervical internal carotid artery (ICA) stenosis underwent CAS using the trans-forearm dual protection technique. RESULTS: A 4F sheath was introduced into the cephalic vein of the right forearm. After an 8F balloon-guiding catheter was navigated into the left common carotid artery (CCA) via right sheathless radial access, a distal filter protection device was advanced into the high cervical ICA. The 8F balloon-guiding catheter was inflated and connected to the 4F sheath with a blood filter interposed. Under the dual protection of flow reversal and distal filter, the CAS procedure was performed. The postprocedural course was uneventful. Diffusion-weighted imaging 2 days after the procedure showed no evidence of ischemic stroke. The patient was discharged home without any complications 1 week after the procedure. Carotid duplex ultrasound performed 9 months after the procedure showed no signs of restenosis. CONCLUSIONS: This method allows for CAS under the dual protection of flow reversal and filter device protection via the trans-forearm access, reducing the risk of embolism and access site complications. Therefore, the trans-forearm dual protection technique can be a useful option for CAS.

Left Transradial Access Using a Radial-Specific Neurointerventional Guiding Sheath for Coil Embolization of Anterior Circulation Aneurysm Associated With the Aberrant Right Subclavian Artery: Technical Note and Literature Review.

BACKGROUND: Aberrant right subclavian artery (ARSA) is a rare condition, but the most common anomaly of the aortic arch. Although neurointerventions via transradial access (TRA) are becoming increasingly popular worldwide, transradial carotid cannulation has been extremely challenging in patients with an ARSA. Herein, we present a case of ARSA-associated anterior communicating artery (ACoA) aneurysm that was successfully treated with a radial-specific 6F Simmons guiding sheath via left TRA. We also review the relevant literature. METHODS: A 68-year-old-woman who was diagnosed as having an ARSA-associated ACoA aneurysm underwent simple coiling via left TRA. After the 6F Simmons guiding sheath was engaged into the right common carotid artery using the pull-back-technique, transradial quadraxial system (6F Simmons guiding sheath/6F intermediate catheter/3.2F intermediate catheter/coil-delivery microcatheter) was implemented. RESULTS: Simple coiling of the aneurysm was successfully achieved without catheter kinking or system instability. The postprocedural course was uneventful. A follow-up magnetic resonance angiography showed no evidence of recanalization 1 years 9 months after the procedure. CONCLUSIONS: Transradial anterior circulation intervention has been rarely used for patients with an ARSA due to unfavorable catheter trajectory. Left TRA using the 6F Simmons guiding sheath is a useful treatment option to address anterior circulation interventions for patients with an ARSA. Preoperative diagnosis of ARSA is necessary for the application of our method.

Real-Time Monitoring of Aneurysm Catheterization During Stent-Assisted Coiling for Irregularly Shaped Intracranial Aneurysms: The Scope Technique.

OBJECTIVE: Stent-assisted coiling (SAC) using the jailing technique is a well-established treatment for wide-neck intracranial aneurysms. However, low-volume packing, which is a key factor for aneurysm recanalization, can occur in patients with irregularly shaped aneurysms. We have devised a real-time monitoring system for aneurysm catheterization that allows the intentional placement of the jailed coil-delivery microcatheter and deployed stent, referred to as the "scope" technique. Herein, we present a case of irregularly shaped anterior communicating artery (ACoA) aneurysm successfully treated with SAC using this technique. METHODS: A 72-year-old woman diagnosed with an unruptured wide-neck ACoA aneurysm that was eccentric to the parent ACoA and overhanging posteriorly underwent SAC using this technique. Bilateral transradial quadraxial systems (6-Fr Simmons guiding sheath/6-Fr intermediate catheter/3.2-Fr intermediate catheter/microcatheter) were established via right and left internal carotid artery. The stent-delivery microcatheter was advanced into the left A2 via the right A1, leaving a 0.014″ microguidewire for visualization under fluoroscopic guidance. To place the coil-delivery microcatheter in the middle of the aneurysm after stent deployment, the coil-delivery microcatheter was cannulated into the aneurysm via the left A1, intendedly through the posterior side of the stent-delivery microcatheter in the down-the-barrel view of the parent ACoA (the scope technique). RESULTS: After stent deployment, SAC of the aneurysm was successfully achieved. CONCLUSIONS: Using this technique, the coil-delivery microcatheter was cannulated into the aneurysm, while monitoring its positional relationship with the stent-delivery microcatheter in real time. This technique is a useful treatment option for irregularly shaped and wide-neck aneurysms.

Surgical Trapping of a Cavernous Carotid Aneurysm Causing Carotid Cavernous Fistula After Flow Diverter Placement: Technical Note and Literature Review.

BACKGROUND: Flow diverter (FD) treatment is a promising therapeutic strategy for intracranial aneurysms such as cavernous carotid aneurysms (CCAs). Direct cavernous carotid fistula (CCF) caused by delayed rupture of FD-treated CCAs has been reported, and endovascular therapy has been used in the literature. Surgical treatment is warranted for patients who have failed or are ineligible for endovascular treatment. However, no studies have evaluated surgical treatment to date. Here, this paper presents the first case of direct CCF due to delayed rupture of an FD-treated CCA managed with surgical internal carotid artery (ICA) trapping with bypass revascularization, in which the intracranial ICA with FD placement was successfully occluded with aneurysm clips. METHODS: A 63-year-old man with a diagnosis of large symptomatic left CCA underwent FD treatment. The FD was deployed from the supraclinoid segment of the ICA distal to the ophthalmic artery to the petrous segment of the ICA. Since angiography 7 months after the FD placement showed progressive direct CCF, left superficial temporal artery-middle cerebral artery bypass followed by ICA trapping was performed. RESULTS: The intracranial ICA proximal to the ophthalmic artery where the FD was placed was successfully occluded using two aneurysm clips. The postoperative course was uneventful. Follow-up angiography 8 months after the surgery confirmed complete obliteration of the direct CCF and CCA. CONCLUSIONS: The intracranial artery in which the FD was deployed was successfully occluded with two aneurysm clips. ICA trapping can be a feasible and useful therapeutic option to treat direct CCF caused by FD-treated CCAs.

Transradial Stent-Assisted Coiling Using "Dual-Jailing" Technique for Kissing Aneurysms of the Internal Carotid Artery: Technical Note and Literature Review.

BACKGROUND: Kissing aneurysms are an unusual type of multiple intracranial aneurysms having different origins with partially adherent walls. Although endovascular treatment is a useful alternative to surgical clipping, endovascular management for small wide-necked kissing aneurysms has not been adequately investigated to date. Herein, we present a case of small wide-necked kissing aneurysms successfully treated with transradial stent-assisted coiling (SAC) using the "dual-jailing" technique. We also performed a review of the relevant literature. CASE PRESENTATION: A 64-year-old woman who was diagnosed with small wide-necked kissing aneurysms relating to the ophthalmic artery underwent SAC using the dual-jailing technique. After a 6F Simmons guiding sheath was delivered into the target common carotid artery via transradial access, a 6F intermediate catheter was navigated into the petrous internal carotid artery to achieve both triple microcatheter manipulation and contrast injection. Two coil-delivery microcatheters were cannulated into each aneurysm, followed by a Neuroform Atlas stent deployment over the aneurysm necks via a third stent-delivery microcatheter. By using the jailed microcatheters, SAC of the kissing aneurysms was successfully achieved, preserving the ophthalmic artery. The postprocedural course was uneventful. A follow-up magnetic resonance angiography showed no evidence of recanalization 2 years 3 months post procedure. CONCLUSIONS: The dual-jailing technique may provide simple and time-saving SAC compared with previous reported method. This technique can be a useful treatment option for small wide-necked kissing aneurysms.

Surgical revascularization for quasi-moyamoya disease associated with polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes (POEMS) syndrome: a case report and literature review.

POEMS (polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes) syndrome is a rare multisystem disease characterized by plasma cell dyscrasia and overproduction of vascular endothelial growth factor, which is related to disease activity. Recent treatment strategies have improved survival of patients suffering from this disorder; however, ischemic stroke remains a poor prognostic factor. POEMS patients with ischemic stroke frequently develop cerebral large artery stenosis/occlusion, followed by progressive stroke. Post literature review, we present an ischemic stroke case of quasi-moyamoya disease linked with this syndrome that was successfully treated with surgical revascularization. A 41-year-old woman diagnosed with POEMS syndrome developed progressive ischemic stroke due to quasi-moyamoya disease, despite decreased vascular endothelial growth factor level with lenalidomide and dexamethasone treatment. She underwent superficial temporal artery to middle cerebral artery bypass with encephalo-duro-myo-synangiosis bilaterally. The postoperative course was uneventful. Two years and five months after the stroke, neuroimaging demonstrated bypass patency, neovascularization after encephalo-duro-myo-synangiosis, and no recurrence of stroke. Our case is the first to report successful surgical revascularization for a POEMS patient. Surgical revascularization may be a useful treatment option for patients with quasi-moyamoya disease associated with POEMS syndrome, especially for those who develop refractory ischemic stroke despite reduced vascular endothelial growth factor level.

Smaller diameter sheaths are required to safely perform transradial neurointerventions.

We read with great interest the paper titled "Transradial access with Simmons guiding catheter for carotid artery stenting: Feasibility and procedural complications in a single-center experience" by Muszynski et al. The authors concluded that a transradial carotid artery stenting (CAS) using a Glidesheath Slender 7F Introducer/7F Envoy Simmons 2 catheter system was feasible with a high procedural success rate and low access site complication rate. We completely agree with their conclusions. In this study, large-diameter sheaths were used. Large sheaths increase the risk of developing radial artery spasms. Interventionalists must be aware that radial artery spasm can not only require an access crossover, but can also cause severe access site complications, such as eversion or avulsion of the radial artery, catheter/sheath entrapment, and compartment syndrome. A 6F Simmons guiding sheath has a smaller outer diameter than the Glidesheath Slender 7F Introducer does, and it offers a large-bore working channel compatible with a 10-mm diameter Wallstent and Acculink. Transradial CAS with a 6F Simmons guiding sheath has previously yielded a high procedural success rate without serious access site complications. Nevertheless, we believe that a further decrease in the sheath diameter is required to safely perform transradial neurointerventions in more patients.

Transradial Mechanical Thrombectomy Using a Radial-specific Neurointerventional Guiding Sheath for Anterior Circulation Large-Vessel Occlusions: Preliminary Experience and Literature Review.

BACKGROUND: Transradial mechanical thrombectomy (MT) is increasingly used because it is associated with a low incidence of vascular access site complications. However, transradial carotid cannulation can be technically challenging to perform in patients with an unfavorable supra-aortic takeoff. In this study, the feasibility and safety of a new transradial MT system with a radial-specific neurointerventional guiding sheath-6F Simmons guiding sheath was evaluated-in patients with anterior circulation large-vessel occlusions. Additionally, a literature review was performed. METHODS: We retrospectively analyzed data from our institutional database about consecutive patients who underwent transradial MT for anterior circulation large-vessel occlusion. After the 6F Simmons guiding sheath was engaged into the target common carotid artery, a triaxial system (Simmons guiding sheath/aspiration catheter/microcatheter), was established. MT using the continuous aspiration prior to intracranial vascular embolectomy technique was performed. Then, procedural success rate, successful revascularization, and procedure-related complications were assessed. RESULTS: A total of 13 patients who had transradial MT were included in the analysis. All 13 patients underwent successful thrombectomy without catheter kinking or system instability, and 12 of them achieved successful revascularization (modified Thrombolysis in Cerebral Infarction score of ≥2b). No complications occurred. CONCLUSIONS: To the best of our knowledge, this is the first case series on transradial MT using a radial-specific neurointerventional system for anterior circulation large-vessel occlusions. This method may increase the success rate of transradial MT. Based on our initial experience, transradial MT, using this system, was feasible and safe for anterior circulation large-vessel occlusions.

New Distal Balloon Protection System for Transradial Carotid Artery Stenting After Percusurge Guardwire Withdrawal: Jailbreak Technique.

BACKGROUND: Embolic protection devices are commonly used to prevent cerebral embolism during carotid artery stenting (CAS). However, the PercuSurge Guardwire device, a distal balloon protection device, was discontinued in April 2021. We present a case of successful CAS using a new distal balloon protection system. The procedure, referred to as the jailbreak technique, was performed via transradial access. METHODS: A 67-year-old man underwent CAS, using the jailbreak technique, for right carotid stenosis with a vulnerable plaque. 6-French (Fr) and 4-Fr Simmons guiding sheaths were delivered into the right common carotid artery via the right and left transradial access, respectively. Distal balloon protection was provided using a 2.6-Fr dual-lumen balloon microcatheter (Pinnacle Blue 20, Tokai Medical Products, Aichi, Japan) via the 4-Fr Simmons guiding sheath. A 4.2-Fr catheter was coaxially delivered proximal to the balloon and distal to the lesion. RESULTS: After CAS was successfully performed via the 6-Fr Simmons guiding sheath, the Pinnacle Blue 20 was retrieved through the 4.2-Fr catheter without interfering with the distal stent flare and stent struts. Postprocedural neuroimaging revealed no evidence of ischemic stroke. CONCLUSIONS: The jailbreak technique allows distal balloon protection during transradial CAS. This is a useful treatment option for patients with carotid stenosis.