Carotid Artery Stenting Using a Closed-Cell Stent-in-Stent Technique for Unstable Plaque.

Purpose: To examine whether carotid artery stenting (CAS) of stenoses with unstable plaque using a closed-cell stent-in-stent technique prevents plaque protrusion. Materials and Methods: Between December 2014 and August 2018, 35 consecutive patients (mean age 75.8 years; 29 men) with carotid artery stenosis (20 symptomatic) and unstable plaque diagnosed by magnetic resonance imaging were prospectively analyzed. Mean diameter stenosis was 83.5%. All CAS procedures were performed with stent-in-stent placement of Carotid Wallstents using an embolic protection device and conservative postdilation. The technical success rate, incidence of plaque protrusion, ischemic stroke rate within 30 days, and new ipsilateral ischemic lesions on diffusion-weighted imaging (DWI) within 48 hours after CAS were prospectively assessed. Follow-up outcomes included the incidences of ipsilateral stroke and restenosis. Results: The technical success rate was 100%. No plaque protrusion or stroke occurred in any patient. New ischemic lesions were observed on DWI in 10 (29%) patients. During the mean 11.6-month follow-up, no ipsilateral strokes occurred. Two (6%) patients developed asymptomatic restenosis recorded as 53% lumen narrowing and occlusion, respectively. Conclusion: CAS using a closed-cell stent-in-stent technique for unstable plaque may be useful for preventing plaque protrusion and ischemic complications.

Carotid Artery Stenting for Near Occlusion with Full Collapse.

OBJECTIVE: Carotid near occlusions show a lower risk of stroke than other types of severe stenosis. However, emerging evidence suggests that near occlusion with full collapse differs from that without full collapse. The results of treatment with carotid artery stenting for near occlusion with full collapse are presented. METHODS: Between March 2007 and December 2020, 18 of 477 carotid artery stenting procedures were performed in patients with near occlusion with full collapse (3.8%). A total of 17 men and one woman with a mean age of 76.1 years were included. Eleven patients (61%) were symptomatic. The technical success rate, incidence of symptomatic stroke within 30 days, new ipsilateral ischemic lesions on diffusion tensor imaging within 48 hours after carotid artery stenting, and follow-up results (ipsilateral stroke rate and restenosis rate) were retrospectively assessed. RESULTS: The technical success rate was 100%. All carotid artery stenting procedures were performed using embolic protection devices. No symptomatic stroke occurred within 30 days. New ipsilateral ischemic lesions on magnetic resonance imaging were observed in 16.7% (3/18) of patients. Asymptomatic minor cerebral hemorrhage occurred in 2 patients (11.1%) with cerebral hyperperfusion syndrome. The median follow-up period was 77 months. Asymptomatic restenosis of 50% occurred in one patient (5.5%), and asymptomatic occlusion occurred in one patient (5.5%). During follow-up, no patients experienced ipsilateral stroke. Three patients (16.7%) died from nonneurological causes. CONCLUSIONS: Carotid artery stenting for near occlusion with full collapse seems to be a feasible and safe procedure that can be performed by an experienced neuro-interventional team.

Usefulness of contrast-enhanced magnetic resonance angiography for follow-up of coil embolization with the enterprise stent for cerebral aneurysms.

OBJECTIVE: The aim of this study was to determine the feasibility and usefulness of contrast-enhanced magnetic resonance angiography (CE-MRA) and 3-dimensional (3D) time-of-flight (TOF) MRA for follow-up of intracranial aneurysms treated using the Enterprise stent. METHODS: Five aneurysm cases using the Enterprise stent were prospectively analyzed and were followed up with CE-MRA, 3D TOF MRA, and digital subtraction angiography (DSA). Depictions of parent artery lumen and the aneurysm neck with 3D TOF MRA and CE-MRA were compared with those of DSA. RESULTS: In all cases, on 3D TOF MRA, it was difficult to evaluate the parent artery lumen and aneurysm neck owing to the significant artifacts from the stent. Contrast-enhanced MRA sufficiently demonstrated parent artery lumen and aneurysm neck distinctly and as clear as DSA did in all cases. CONCLUSIONS: For follow-up after coiling with an Enterprise stent, CE-MRA may be necessary to avoid susceptibility artifacts caused by the stent.

Initial Experience of Coil Embolization for Unruptured Intracranial Aneurysm Combined with Neuroform Atlas and Undersized Flexible Coils.

Objective: Intraprocedural rupture (IPR) is a rare complication that can occur during endovascular treatment (EVT) of unruptured intracranial aneurysms (UIAs). However, it leads to high morbidity and mortality rates. Others have showed that coil flexibility is a risk factor for IPR. Neuroform Atlas (NA) stents can be deployed with 0.0165-inch microcatheters to enable stent assisted coiling (SAC) with a high likelihood. Undersized flexible coils can be inserted initially during SAC. This study aimed to determine whether SAC using NA and highly flexible coils for UIAs can be conducted without IPR. Methods: We retrospectively analyzed nine consecutive patients (mean age, 73.2 years; female, n = 6) who underwent SAC for UIAs combined with NA stents and undersized flexible coils between January 2017 and December 2019. Two aneurysms were located at the internal carotid artery (ICA), and one each was located at the ICA-posterior communicating, anterior communicating, middle cerebral, vertebral, vertebra-posterior inferior cerebral and basilar arteries. The mean size of the aneurysms was 4.6 (range, 3.1-8.6) mm. SAC proceeded using the jailing technique. All coils were selected from among the most flexible coils available. We retrospectively assessed technical success rates, aneurysm occlusion at final digital subtraction angiography (DSA), volume embolization ratios (VERs), rates of IPR and symptomatic stroke within 30 days, angiographic findings of aneurysm occlusion at 3 months post-procedure and late adverse events (frequency of aneurysmal rupture, ipsilateral ischemic stroke, and retreated targeted aneurysms). Results: The technical success rate was 100%. Complete occlusion (CO) was immediate in 8 (89%) patients and a neck remnant persisted in 1 (11%). No IPR or symptomatic stroke developed within 30 days. During a mean follow-up period of 11.8 months, CO persisted in 8 (89%) patients. No late adverse events occurred. Conclusion: The early clinical and angiographic findings of SAC for UIAs combined with an NA stent and undersized flexible coils were favorable for this series.

Hyponatremia is predictable in patients with aneurysmal subarachnoid hemorrhage--clinical significance of serum atrial natriuretic peptide.

PURPOSE: Serum atrial natriuretic peptide (ANP) that is elevated after aneurysmal subarachnoid hemorrhage (SAH) causes diuresis and natriuresis (cerebral salt wasting) and might exacerbate delayed ischemic neurological deficit (DIND). We investigated relationships among hyponatremia, serum ANP elevation, and the onset of DIND after SAH. MATERIALS AND METHODS: Thirty-nine consecutive patients (15 women and 24 men) with SAH were assigned to a normonatremia group or a group that developed hyponatremia after SAH. Serum ANP and brain natriuretic peptide were assessed after SAH. All patients remained normovolemic and normotensive. We attributed DIND to vasospasm only in the absence of other causes and when supported by cerebral angiography. RESULTS: Hyponatremia developed after SAH in 11 patients (28.2%), among whom serum ANP concentrations at 0 and 3 days thereafter were significantly increased. Furthermore, DIND developed in five (45.5%) and two (7.1%) hyponatremic and normonatremic patients, respectively (P < 0.05). The serum ANP levels on day 0 after SAH were higher in Hunt and Kosnik grades 3-4 than in 1-2 and in Fisher groups 3-4 than in 1-2 (P < 0.05). CONCLUSIONS: Increasing serum ANP concentrations were independently associated with hyponatremia resulting in DIND. Early treatment of hyponatremia might prevent DIND in patients after SAH.

Virtual surgical planning for superficial temporal artery to middle cerebral artery bypass using three-dimensional digital subtraction angiography.

OBJECTIVE: To introduce reliable and minimally invasive virtual surgical planning for superficial temporal artery to middle cerebral artery (STA-MCA) bypass surgery using three-dimensional (3-D) rotational reconstruction digital subtraction angiography (DSA). METHODS: Twenty-eight consecutive patients (11 women and 17 men) with cerebrovascular insufficiency due to internal carotid artery (ICA) or middle cerebral artery (MCA) occlusion (n = 16), ICA or MCA stenosis (n = 6), and moyamoya or moyamoya-like disease (n = 6) underwent rotational DSA. Anatomical locations of the appropriate donor branch of the STA, the most suitable recipient of MCA and squamous sutures on the skull surface, were visualized using 3-D reconstruction imaging. Localization of the minicraniotomy, the skin incision on top of the superficial temporal artery branch, and the anastomosis point were accurately determined by virtual surgical planning. RESULTS: According to preoperative assessments, the minimum necessary skin incision and small craniotomy were successfully achieved. The preselected artery was found without additional craniotomy and anastomosed at the putative point in all patients. Perioperative complications did not arise and all bypasses remained patent on follow-up. CONCLUSION: Preoperative 3-D virtual surgical planning assessments are exactly consistent with operative findings. Such assessments avoid unnecessary manipulation and simplify the surgical procedure. This imaging technique is helpful for planning STA-MCA bypass surgery.

Multiple cerebral aneurysms associated with Takayasu arteritis successfully treated with coil embolization.

The cerebrovascular complications of Takayasu arteritis are primarily related to the presence of occlusive lesions. Cerebral aneurysms rarely occur as complications; only 18 cases have been reported thus far. The use of coil embolization to treat cerebral aneurysms occurring as a complication of Takayasu arteritis has not been previously reported. We report a case of Takayasu arteritis with a basilar tip aneurysm and a P1 segment aneurysm of the left posterior cerebral artery that were successfully treated with coil embolization. Because coil embolization for cerebral aneurysms associated with Takayasu arteritis requires the use of limited access routes that have extremely curved and tortuous courses, catheter navigation was difficult. The guide catheter, microcatheter, and guidewire must be selected and navigated with greater care than is usually required for common aneurysm embolization.

Initial experience of using the filter protection device during carotid artery stenting in Japan.

PURPOSE: No filter protection devices for carotid artery stenting (CAS) have been formally approved for use in Japan; however, as of April 2008, the Angioguard XP (AGXP) was approved. This article describes our initial results using the AGXP during CAS for the treatment of carotid artery stenosis. MATERIAL AND METHODS: A group of 15 patients (14 men) with a mean age of 72.3 years (range 53-81 years) were treated by CAS using the AGXP. Among them, 10 were symptomatic with >50% stenosis of the common or internal carotid artery (ICA), and 5 were asymptomatic with >70% stenosis. The rates of technical success, periprocedural stroke, ICA flow impairment, filter movement, and development of new ischemic lesions on diffusion-weighted imaging (DWI) were assessed. RESULTS: CAS using the AGXP was successful in all cases. There was one minor stroke, and flow impairment occurred in six patients. Filter movement averaged 1.9 vertebral bodies. DWI showed new ipsilateral ischemic lesions in eight of the patients. CONCLUSION: Initial clinical experience using the AGXP for CAS has been generally sufficient. However, attention must be paid to three problems when using the AGXP: the filter may move after placement; the filter may disturb blood flow in the ICA; and debris may pass around the filter.

Successful percutaneous transluminal angioplasty and stenting for symptomatic intracranial vertebral artery stenosis using intravascular ultrasound virtual histology.

This is the first report of percutaneous transluminal angioplasty (PTA) of an intracranial artery applying intravascular ultrasound virtual histology (IVUS-VH), which has been recently developed for tissue characterization of coronary artery plaque. We report a case of successful PTA and stenting for symptomatic intracranial vertebral artery stenosis using IVUS-VH.

Carotid Artery Stenting: Investigation of Plaque Protrusion Incidence and Prognosis.

OBJECTIVES: This study sought to clarify the incidence and prognosis of PP in carotid artery stenting (CAS). BACKGROUND: Projections thought to be plaque may be observed inside the stent on angiography or intravascular ultrasound (IVUS) during CAS. Known as plaque protrusion (PP), the incidence and prognosis of this complication are unclear. METHODS: A total of 354 consecutive carotid atherosclerotic stenoses in 328 patients (285 men, 43 women; age range 51 to 97 years [mean age 73.6 years]; 158 symptomatic cases; stenosis rate, 50% to 99% [mean 81.0%]) who underwent CAS under IVUS between October 2007 and March 2016 were retrospectively analyzed. PP was defined as plaque seen inside the stent lumen on both digital subtraction angiography and IVUS. The incidence and prognosis (rate of stroke within 30 post-operative days) of PP and the rate of ischemic lesions on the treated side on diffusion-weighted imaging performed within 48 post-operative hours within the PP group were investigated. RESULTS: PP was observed in 9 cases (2.6%). Ischemic stroke occurred in 6 of 9 PP cases (66.7%; 1 major, 5 minor). Ischemic lesions were observed on diffusion-weighted imaging in 8 of 9 cases (88.9%). PP was strongly associated with perioperative ischemic stroke. A significant increase in PP susceptibility was observed with open-cell stent use and unstable plaque. CONCLUSIONS: The incidence of PP in CAS was 2.6%, with a high risk of ischemic complications if PP was observed. The present findings indicate the necessity of appropriate device selection to avoid PP.

Stent Placement for Severe Stenosis of the Left Common Carotid Artery with Internal-to-External Carotid Steal.

We report the case of a 64-year-old male with internal carotid artery (ICA)-to-external carotid artery (ECA) steal due to severe stenosis of the common carotid artery (CCA). Left CCA occlusion was initially diagnosed on 3-dimensional time-of-flight magnetic resonance angiography, but digital subtraction angiography revealed severe stenosis of the left CCA and retrograde flow through the left ICA feeding the left ECA. Diverted blood flow from ECA to ICA in cases with occlusion or severe stenosis of the CCA represents a well-known alternative collateral flow pattern called ECA-to-ICA steal. However, collateral flow from ICA to ECA is rarely observed and may be termed ICA-to-ECA steal. We treated CCA stenosis in our patient by carotid artery stenting (CAS) because his CCA stenosis had been gradually progressing since the initial ischaemic attack. Antegrade ICA flow subsequently recovered. To the best of our knowledge, this is the first report of ICA-to-ECA steal normalised by the treatment of CCA stenosis using CAS.

Pathogenesis of intraparenchymal epidermoid cyst in the brain: a case report and review of the literature.

BACKGROUND: Intracranial epidermoid cysts are relatively common; however, epidermoid cysts in the brain parenchyma are rare. In addition, the etiology of intraparenchymal epidermoid cysts is not clear. CASE DESCRIPTION: A 61-year-old woman presented with convulsive seizures. CT and MRI revealed a mass lesion in the right parietal lobe. With low-grade glioma as a preoperative diagnosis, the tumor was totally excised, but the subsequent pathologic diagnosis was epidermoid cyst. CONCLUSION: Exact preoperative diagnosis of this disease would be helpful in preventing chemical meningitis. The etiology is likely related to the time and locus of sequestration of ectodermal tissue during fetal development. Clarifying the pathogenesis will lead to effective preventive measures.

Carotid Wallstent placement difficulties encountered in carotid artery stenting.

PURPOSE: The present study aimed to identify the types of curved lesions that are difficult to place Carotid Wallstent (CWS). MATERIALS AND METHODS: The study targeted 31 consecutive carotid artery (CA) stenosis underwent carotid artery stenting using CWS. CWS placement success rate, stenosis location, lesion tortuosity, and relationship with stent placement failures were investigated. Lesion tortuosity was defined as the angle formed by 2 tangential lines between internal CA and common CA from the inflection point (IP) was defined as the center of lesion curvature. Stenosed lesions were classified into type A or B. Type A was defined as if the distal end of the stenosis was located proximal to the IP at a distance ≥0.5 of a vertebral body based on the posterior height of the 3rd vertebral body, otherwise was type B. RESULTS: The stent placement success rate was 93.5% (29/31). The 2 unsuccessfully stented lesions, both lesions were significantly different from other lesions by having a lesion tortuosity less than 90° and by belonging to type B. CONCLUSION: Since CWS placement is difficult in patients with CA stenosis located close to the IP at a lesion tortuosity ≤90°, open-cell stents should be considered as an alternative.

Hemifacial spasm due to contralateral aneurysmal compression of the facial nerve successfully treated with endovascular coil embolization: case report.

BACKGROUND AND IMPORTANCE: Hemifacial spasm is usually caused by compression of the facial nerve at the root exit zone (REZ), whereas fusiform aneurysmal compression is extremely rare. The authors describe symptomatic hemifacial spasm caused by a contralateral fusiform aneurysm of the vertebral artery (VA) that was treated by endovascular coil embolization. CLINICAL PRESENTATION: A 55-year-old woman developed left hemifacial spasm that had gradually worsened over a period of 2 years before admission to our hospital. Cerebral angiography showed an elongated right VA fusiform aneurysm near the VA union that inclined toward the left side. The cause of the facial spasm was considered to be compression of the left facial nerve REZ by the aneurysm. Endovascular parent artery embolization including the aneurysm was performed. The hemifacial spasm disappeared within 3 months. CONCLUSION: Hemifacial spasm caused by contralateral VA fusiform aneurysm can be treated by intravascular parent artery occlusion with coil embolization.

Initial experience of carotid artery stenting using the Carotid WALLSTENT and FilterWire EZ in Japan.

PURPOSE: The Carotid WALLSTENT (CWS) and Filter-Wire EZ (FWEZ) embolic protection devices for use in carotid arterial stenting (CAS) were newly approved for national health insurance coverage in Japan in April 2010. This article describes our initial experience of CAS using the CWS and FWEZ. MATERIAL AND METHODS: A group of 14 patients (12 men, 2 women; mean age 70.1 years, range 59-83 years) with 15 carotid artery stenoses at high risk for carotid endarterectomy were treated by CAS using the CWS and FWEZ. Of these stenoses, 5 were symptomatic with ≥50% stenosis of the common or internal carotid artery (ICA), and 10 were asymptomatic with ≥80% stenosis. The rates of technical success, ICA flow impairment during filter protection, periprocedural ischemic stroke, 30-day major adverse events (MAEs) (stroke, death, myocardial infarction), and development of new ischemic lesions on diffusion-weighted imaging (DWI) were assessed. RESULTS: CAS was successful in all cases. There was no ICA flow impairment, periprocedural ischemic stroke, or MAEs. DWI showed new ipsilateral ischemic lesions in only one patient (6.7%). CONCLUSION: Our initial clinical experience using the CWS and FEWZ for CAS was generally excellent, and the incidence of postprocedural ischemic lesions was low.

[Increased urinary sodium excretion in the early phase of aneurysmal subarachnoid hemorrhage as a predictor of cerebral salt wasting syndrome].

Cerebral salt wasting syndrome (CSWS) in patients with aneurysmal subarachnoid hemorrhage (SAH) is considered to correlate with delayed ischemic neurological deficits (DIND) induced by cerebral vasospasm; however, its exact mechanism is still not well-known. The purpose of the present study is to evaluate the relationship between hyponatremia caused by CSWS and the increase of the urinary sodium excretion in early phase following SAH. Fifty-four patients with SAH were divided into 2 groups, normonatremia group and hyponatremia group which suffered hyponatremia after SAH. The hyponatremia group comprise 14 patients (26%) in whom the hyponatremia developed of the SAH. In this group, the serum level of sodium significantly decreased 7 days after SAH and then gradually normalised. Further, excretion of sodium in the urine tended to increase 3 days after SAH and significantly increased 7 days after SAH. In conclusion, the increased urinary sodium excretion in the early phase of SAH would serve as a predictive factor for CSWS after SAH. We consider that it is important to start sodium and fluid supplementation and inhibit natriuresis by fludrocortisone acetate administration before hyponatremia occurs in order to prevention delayed ischemic neurological deficits in SAH patients.