Objective: The influence of stent cell design on cerebral embolism after carotid artery stenting (CAS) is not well understood. The purpose of this study was to evaluate the influence of stent cell design on the incidence of periprocedural cerebral embolism in tailored CAS.
Materials and Methods: A total of 114 symptomatic and asymptomatic cases of carotid artery stenosis were treated with CAS. The stent type included closed-cell stent and open-cell stent (48 closed-cell and 66 open-cell stents). Procedural, imaging, and clinical outcomes were retrospectively assessed and compared between the closed-cell stent group and the open-cell stent group.
Results: Periprocedural neurological complications were not significantly different between the two groups (p = 0.4). The presence of new ischemic lesions and number of new ischemic lesions on post procedural examination were not significantly different between the two groups (p = 0.32, p = 0.4).
Conclusion: Stent selection according to the morphological and clinical characteristics is thought to be important to reduce periprocedural ischemic complications.
Objective: The stability of the microcatheter is important in safe coil deployment. However, quantitative information regarding the relationship between the microcatheter shape and stability is limited. We investigated deformation characteristics of the microcatheter by applying loads to the tip of a placed microcatheter using numerical analysis.
Materials and Methods: Microcatheter models were prepared by connecting cylindrical rigid segments with coil springs. Four types of models with shapes mimicking parts of a blood vessel and three types of models with shapes that come into contact with the vascular wall on the opposite side of the aneurysm were prepared.
Results: When the distance between the tip of the microcatheter and the position of its contact with the vascular wall exceeded 12 mm, the suppressive effect on displacement of the microcatheter tip was markedly reduced. When this distance was less than 6 mm, the microcatheter shape exerted a greater effect on the stability than the distance.
Conclusion: These results suggest that not only the position of contact of the microcatheter with the vascular wall but also the shape of the microcatheter near the aneurysm plays an important role in securing the stability.
Objective: Cerebral hyperperfusion syndrome (CHS) including intracranial hemorrhage (ICH) is a serious complication after carotid artery stenting (CAS). Therefore, neurointerventionalists in Japan commonly stratify the risk for CHS preprocedurally in CAS candidates using various imaging tests that are available, and sometimes performed preventive methods against CHS, such as staged angioplasty (SAP), undersized-balloon angioplasty followed by delayed CAS. In the current study, we used a nationwide questionnaire survey to clarify the current status of the periprocedural management against CHS and the 30-day outcomes of patients with a high risk of CHS after undergoing CAS or endovascular carotid revascularization procedures, such as SAP or stand-alone angioplasty. This study specifically analyzed the data for the periprocedural management against CHS.
Materials and Methods: Between June and August 2014, questionnaires were emailed to all of the neurointerventional specialists certified by the Japanese Society for Neuroendovascular Therapy (JSNET). If two or more specialist physicians belonged to an institute, a representative physician of the institute answered the questionnaire. This study focused on 14 items of the questionnaire that were directed at examining the preprocedural imaging tests done to evaluate the risk of CHS, the periprocedural management strategies used to prevent CHS, and the postprocedural imaging tests to detect hyperperfusion phenomenon, among others.
Results: Replies were obtained from 154 institutes which represented 336 JSNET-certified neurointerventional specialists. Preprocedural imaging tests done to evaluate the risk of CHS were performed in 144 institutes (93.5%), with single-photon emission CT (SPECT) the most used modality in 88.2% of the institutes. Acetazolamide challenge was performed in 114 (89.8%) of 127 institutes that used preprocedural SPECT evaluation. Of the institutes performing preprocedural CHS-risk evaluation, general anesthesia was administered during the procedure in 44.4%, periprocedural edaravone (a free radical scavenging agent) was used in 52.1%, and periprocedural strict blood pressure control was performed in 91.7%. Postprocedural intravenous anticoagulation therapy was not used for patients with a high risk of CHS in 63.2%. Postprocedural imaging tests to detect hyperperfusion phenomenon were undertaken in 99.3% of the institutes performing preprocedural CHS-risk evaluation. The leading imaging modality, SPECT, was used in 78.3%. SAP was attempted or performed in 27.1% of the institutes.
Conclusion: The present study demonstrated that Japanese practitioners attempt to prevent CHS after carotid endovascular revascularization procedures. Most Japanese neurointerventionalists preprocedurally evaluated the risk of CHS in CAS candidates primarily using SPECT with acetazolamide challenge. The penetration rate for SAP was 27.1% of the institutes.
Objective: When internal carotid artery occlusion is performed for the treatment of an aneurysm, it is important to judge whether or not bypass surgery should be performed for the prevention of complications by the balloon occlusion test (BOT), but there are no clear criteria for the judgment. In this study, we evaluated the long-term results in patients who underwent internal carotid artery occlusion without bypass surgery.
Methods: In all, 33 patients with 34 aneurysms who showed no symptoms, a venous phase delay of within 2 seconds, and a mean stump pressure of ≥40 mmHg on a 20-minute BOT between April 2001 and March 2015 and were treated by endovascular internal carotid artery occlusion under local anesthesia without bypass surgery were evaluated.
Results: There were no periprocedural deaths, periprocedural ischemic complications were observed in four patients (12%), and they persisted in two patients (6%). On postprocedural diffusion-weighted magnetic resonance (MR) imaging, high intensity signal areas were observed in 25 patients (75%). In all, 30 patients could be followed up on an outpatient basis, and symptomatic cerebral infarction, which was cardiogenic, was noted in one patient (3.3%) during a mean follow-up period of 65.3 months. The final evaluation using DSA or MRA, which was performed after a mean of 63.7 months, revealed aneurysm recurrence in one patient and de novo aneurysm formation in one patient.
Conclusion: With judgment of whether or not bypass surgery should be performed according to the results of the BOT, endovascular internal carotid artery occlusion is a safe treatment with a favorable long-term outcome.
Objective: The Pipeline Embolization Device (PED) (Covidien, Irvine, CA, USA) is an endovascular microcatheter delivery system for the curative reconstruction of parent arteries harboring large/giant, wide-necked, and fusiform intracranial aneurysms. Here, we describe our initial experience with the PED to evaluate its safety, complications, and effectiveness.
Methods: We retrospectively reviewed 23 consecutive patients who had received PED endovascular treatment of 23 intracranial aneurysms of the internal carotid artery between the petrous and superior hypophyseal segments between November 2015 and August 2016.
Results: A total of 11 complications were experienced by nine patients with a mean follow-up period of 6.5 months. Five major complications defined as ipsilateral stroke in four patients were encountered: two procedure-related ischemic strokes, one delayed ischemic stroke, and two intracerebral hemorrhages. In one patient, the symptom was persistent 3 months post-procedure. Of the other five patients with complications, four went on to recover completely 3 months post-procedure. Overall, the total complication rate for treatment with PED was 39.1% (9/23). Morbidity rate at 3 months post-procedure was 8.7% (2/23), and mortality rate 3 months post-procedure was 0%. Angiographic follow-up examination was carried out in 10 patients at 6 months and revealed no filling (0%) of aneurysm in four patients, entry remnant (<5%) in five, and subtotal filling (5%–95%) in another patient.
Conclusion: The PED placement is effective therapy for the treatment of large/giant and wide-necked intracranial aneurysms. Despite the relatively low rate of permanent complications associated with the PED, it is important to note that the total complication rate was not negligible.
Objective: Common carotid artery occlusion (CCAO) is much rarer than internal carotid artery occlusion (ICAO). Many cases of intracranial aneurysms due to hemodynamic stress caused by ICAO have been reported. On the other hand, only seven cases of intracranial ruptured aneurysms with CCAOs have been reported. We report the two patients with CCAOs and unruptured posterior cerebral artery (PCA) aneurysms.
Case Presentations: The two patients presented CCAOs and unruptured PCA aneurysms. Digital subtraction angiography (DSA) showed that these patients had collateral circulation from the ipsilateral vertebral artery to the internal carotid artery via the external carotid artery (ECA). We observed that the collateral circulation could become stagnant due to neck extension in patients with CCAO.
Conclusion: Physicians should be aware of this phenomenon and preoperatively determine whether ischemic symptoms occur under neck extension in patients with CCAOs accompanied by intracranial aneurysms.
Objective: Vertebro-vertebral arteriovenous fistula (VVAVF) is a rare disorder that often forms a high blood flow shunt. It is mostly due to trauma, but it is occasionally caused by systemic diseases. Segmental arterial mediolysis (SAM) is characterized by non-inflammatory/non-atherosclerotic segmental lysis of the arterial media and is often diagnosed due to intraperitoneal hemorrhage from a ruptured abdominal visceral artery.
Case Presentation: A 45-year-old male with right VVAVF presented with pulsating tinnitus and underwent coil embolization of the right vertebral artery around the fistula. Cerebral angiography disclosed multiple aneurysms in the head and neck region. Abdominal contrast-enhanced CT showed a dissecting aneurysm extending from the celiac artery to the splenic artery. Since impending rupture was suspected, the aneurysm was embolized later at the radiology department.
Conclusion: A case of VVAVF complicated by SAM is reported. If multiple arterial abnormalities are observed, systemic examination and appropriate intervention are important.
Objective: We treated a patient with carotid artery stenosis complicating scleroderma by carotid artery stenting (CAS) and achieved satisfactory dilation. Since scleroderma was suspected to have induced carotid artery stenosis, we report the case with a review of the literature.
Case Presentation: The patient was a 75-year-old woman diagnosed with scleroderma 8 years before. She thereafter developed polymyositis, liver cirrhosis, and stenosis of the bilateral internal carotid arteries; as progression of stenosis was observed, treatment was considered necessary. In consideration of the patient's general condition, CAS by the transbrachial approach was selected. There was no complication associated with the procedure, and satisfactory dilation could be achieved. No restenosis was observed 6 months after the procedure. The history of previous disorders and the results of antibody tests strongly suggested scleroderma as a cause of carotid artery stenosis.
Conclusion: We performed CAS in a patient with carotid artery stenosis suspected to have been caused by scleroderma and obtained a favorable outcome.