Neurointervention最新文献

Purpose: To compare the embolization effects of a non-fibered pushable coil with a conventional fibered pushable coil in an in vitro bench-top experiment.

Materials and methods: A simplified vascular phantom with 4 channels (1 for the non-fibered coil, 1 for the fibered coil, and 2 for continuous circuit flow) was used. A single coil of the longest length was inserted to evaluate the effect of single-coil embolization, and 3 consecutive coils were inserted to assess the effect of multiple-coil embolization. Post-embolization angiography was performed to obtain flow variables (time to peak [TTP], relative peak intensity [rPI], and angiographic flow reduction score [AFRS]) from time density curves. The packing densities of the two coil types were calculated, and the AFRS of each channel was determined by dividing the TTP by the rPI.

Results: When inserting a single coil, the conventional fibered coil demonstrated better flow reduction, as indicated by a higher AFRS (25.6 vs. 17.4, P=0.034). However, the non-fibered coil exhibited a significantly higher packing density (12.9 vs. 2.4, P=0.001). Similar trends were observed with multiple coils.

Conclusion: The conventional fibered pushable coil showed better flow reduction efficiency, while the non-fibered pushable coil had a higher packing density, likely due to the flexibility of the coil loops. A better understanding of the distinct characteristics of different pushable coils can enhance the outcomes of various vascular embolization.

Vertebral artery stump syndrome (VASS) is a rare condition that can cause posterior circulation ischemic stroke due to occlusion of the ipsilateral vertebral artery (VA) orifice, resulting in blood flow stagnation and embolus formation. Although there is no established treatment for this condition, we observed 3 cases of VASS out of 326 acute ischemic stroke cases at a single institution from April 2021 to October 2022. Despite the best possible antithrombotic treatment, all 3 patients had recurrent ischemic strokes. One patient underwent drug-eluting stenting of the VA orifice to relieve occlusive flow. The other 2 patients received coil embolization, which resulted in the disappearance of their culprit collateral flow. None of the patients had recurrent ischemic strokes after endovascular intervention. Based on our observations, stenting and coil embolization are effective methods for preventing future recurrences of VASS.

Purpose: Cutting balloon-percutaneous transluminal angioplasty (CB-PTA) is a feasible treatment option for in-stent restenosis (ISR) after carotid artery stenting (CAS). However, the longterm durability and safety of CB-PTA for ISR after CAS have not been well established.

Materials and methods: We retrospectively reviewed medical records of patients with ISR after CAS who had been treated with CB-PTA from 2012 to 2021 in our center. Detailed information of baseline characteristics, periprocedural and long-term outcomes, and follow-up imaging was collected.

Results: During 2012-2021, a total of 301 patients underwent CAS. Of which, CB-PTA was performed on 20 lesions exhibiting severe ISR in 18 patients following CAS. No patient had any history of receiving carotid endarterectomy or radiation therapy. These lesions were located at the cervical segment of the internal carotid artery (n=16), proximal external carotid artery (n=1), and distal common carotid artery (n=1). The median time interval between initial CAS and detection of ISR was 390 days (interquartile range 324-666 days). The follow-up period ranged from 9 months to 9 years with a median value of 21 months. Four patients (22.2%) were symptomatic. The average of stenotic degree before and after the procedure was 79.2% and 34.7%, respectively. Out of the 18 patients receiving CB-PTA, 16 (88.9%) did not require additional stenting, and 16 (88.9%) did not experience recurrent ISR during the follow-up period. Two patients who experienced recurrent ISR were successfully treated with CB-PTA and additional stenting. No periprocedural complication was observed in any case.

Conclusion: Regarding favorable periprocedural and long-term outcomes in our single-center experience, CB-PTA was a feasible and safe option for the treatment of severe ISR after CAS.

Artificial intelligence (AI) is revolutionizing stroke care by enhancing diagnosis, treatment, and outcome prediction. This review examines 505 original studies on AI applications in ischemic stroke, categorized into outcome prediction, stroke risk prediction, diagnosis, etiology prediction, and complication and comorbidity prediction. Outcome prediction, the most explored category, includes studies predicting functional outcomes, mortality, and recurrence, often achieving high accuracy and outperforming traditional methods. Stroke risk prediction models effectively integrate clinical and imaging data, improving assessments of both first-time and recurrent stroke risks. Diagnostic tools, such as automated imaging analysis and lesion segmentation, streamline acute stroke workflows, while AI models for large vessel occlusion detection demonstrate clinical utility. Etiology prediction focuses on identifying causes such as atrial fibrillation or cancer-associated thrombi, using imaging and thrombus analysis. Complication and comorbidity prediction models address stroke-associated pneumonia and acute kidney injury, aiding in risk stratification and resource allocation. While significant advancements have been made, challenges such as limited validation, ethical considerations, and the need for better data collection persist. This review highlights the advancements in AI applications for addressing key challenges in stroke care, demonstrating its potential to enhance precision medicine and improve patient outcomes.

A rupture of a femoral pseudoaneurysm is an extremely rare complication of endovascular procedures, but its outcome can be life-threatening. In this report, we present a case of a femoral pseudoaneursym rupture in a patient in their early 90s following intra-arterial mechanical thrombectomy for acute ischemic stroke. Despite receiving medical and surgical interventions, the patient subsequently developed multiple organ failure, ultimately resulting in death. This case emphasizes the critical role of appropriate selection of vascular closure technique and careful post-procedural monitoring, particularly in high-risk patients.

Isolated posterior communicating artery (PCoA) aneurysms are rare, predominantly fusiform in morphology, and rarely present with subarachnoid hemorrhage. Endovascular management of this pathology is technically challenging due to extreme tortuosity, the artery course in the subarachnoid space, sharp angulations at PCoA junctions with the parent artery, and, at times, associations with either internal carotid artery or basilar artery occlusions. We present a case of a ruptured fusiform PCoA at the junction of middle and distal third with concomitant proximal basilar artery occlusion. The PCoA reforms the posterior circulation, making it a vital artery. Stent-assisted coiling was performed with extreme difficulty in achieving distal positioning of the stents in the basilar artery/posterior cerebral artery/distal PCoA due to artery tortuosity. There was technical difficulty in the stent deployment. After changing strategies to a larger diameter laser-cut stent, endovascular treatment could be performed. There were good angiographic and clinical outcomes with stable occlusion at 6-month-follow-up.

We present a case of delayed migration of an open-cell design carotid stent, which is a rare complication following carotid artery stenting (CAS). A 65-year-old patient with carotid artery stenosis underwent CAS with an open-cell stent, initially achieving successful deployment. However, 4 months later, the stent migrated and resulted in restenosis. The patient underwent balloon angioplasty and received an additional stent, leading to improved blood flow. The rarity of stent migration, particularly in the absence of risk factors, highlights the need for clinicians to be vigilant and consider early imaging follow-up for patients at risk of this complication after CAS.

Purpose: Low levels of low-density lipoprotein cholesterol (LDL-C) have been suggested to increase the risk of hemorrhagic transformation (HT) following acute ischemic stroke. However, the literature on the relationship between LDL-C levels and post-thrombectomy HT is sparse. The aim of our study is to investigate the association between LDL-C and delayed parenchymal hematoma (PH) that was not seen on immediate post-thrombectomy dual-energy computed tomography (DECT).

Materials and methods: A retrospective analysis was conducted on all patients with anterior circulation large vessel occlusion who underwent thrombectomy at a comprehensive stroke center from 2018-2021. Per institutional protocol, all patients received DECT immediately post-thrombectomy and magnetic resonance imaging or CT at 24 hours. The presence of immediate hemorrhage was assessed by DECT, while delayed PH was assessed by 24-hour imaging. Multivariable analysis was performed to identify predictors of delayed PH. Patients with hemorrhage on immediate post-thrombectomy DECT were excluded to select only those with delayed PH.

Results: Of 159 patients without hemorrhage on immediate post-thrombectomy DECT, 18 (11%) developed delayed PH on 24-hour imaging. In multivariable analysis, LDL-C (odds ratio [OR], 0.76; P=0.038; 95% confidence interval [CI], 0.59-0.99; per 10 mg/dL increase) independently predicted delayed PH. High-density lipoprotein cholesterol, triglyceride, and statin use were not associated. After adjusting for potential confounders, LDL-C ≤50 mg/dL was associated with an increased risk of delayed PH (OR, 5.38; P=0.004; 95% CI, 1.70-17.04), while LDL-C >100 mg/dL was protective (OR, 0.26; P=0.041; 95% CI, 0.07-0.96).

Conclusion: LDL-C ≤50 mg/dL independently predicted delayed PH following thrombectomy and LDL-C >100 mg/dL was protective, irrespective of statin. Thus, patients with low LDL-C levels may warrant vigilant monitoring and necessary interventions, such as blood pressure control or anticoagulation management, following thrombectomy even in the absence of hemorrhage on immediate post-thrombectomy DECT.

Transarterial embolization using Onyx is a well-established treatment for dural arteriovenous fistulas (DAVFs). However, complications can arise when Onyx migrates into the venous side, impairing the draining veins. We encountered a case where Onyx, injected through the arterial side, strayed into the jugular vein, forming a hairball-like structure. Our study aimed to investigate the underlying mechanism of this unusual phenomenon. We postulated that Onyx precipitates into thread-like shapes when passing through extremely narrow openings. To test this, we extruded Onyx from a syringe through a 27-gauge needle into a silicone tube with flowing water. By varying the flow speed, we observed the hardening behavior of Onyx. Under slow flow, the extruded Onyx quickly solidified at the needle tip, forming a round mass. Conversely, high-speed flow resulted in Onyx being dispersed as small pieces. We successfully replicated the formation of "Onyx threads" under continuous slow flow conditions, similar to our case. This phenomenon occurs when Onyx unexpectedly migrates to the draining vein through a tiny opening during transarterial embolization for arteriovenous shunt diseases. Early recognition and appropriate measures are necessary to prevent occlusive complications in the draining veins and the pulmonary system.