Acute Occlusion of the Distal Internal Carotid Artery : Single Center Experience in 46 Consecutive Cases, review of the literature and proposal of a classification

Accuracy of Computed Tomography Angiography for Diagnosing Extracranial Mural Lesions in Patients with Acute Internal Carotid Artery Occlusion: Correlation with Digital Subtraction Angiography

Extracranial carotid mural lesions (CML), caused by atherosclerosis or dissection, are frequently observed in acute internal carotid artery (ICA) occlusion, often requiring angioplasty or stenting. This study aimed to assess the diagnostic accuracy of computed tomography angiography (CTA) in differentiating extracranial CML from thromboembolic etiology in acute ICA occlusion in patients eligible for endovascular treatment. Two neuroradiologists retrospectively studied patients with apparent extracranial ICA occlusion on CTA. Patients were divided into two groups: thromboembolism and CML, based on findings from CTA and digital subtraction angiography (DSA). CTA sensitivity and specificity were calculated using DSA as the gold standard. Occlusive patterns and cervical segment widening were evaluated for atherosclerosis, dissection, and thromboembolism etiologies. CTA had a sensitivity of 84.91% (74.32-95.49%) and a specificity of 95.12% (87.31-100%) in detecting extracranial CML. Atherosclerosis was the most common cause, distinguishable with high accuracy using CTA (p < 0.001). No significant differences were found in occlusive patterns between dissection and thromboembolism (p = 0.568). Cervical segment widening was only observed in dissection cases due to mural hematoma. Conclusions: CTA accurately differentiates extracranial CML from thromboembolic etiology in acute ICA occlusion. The pattern of the occlusion and the artery widening help to establish the location and the etiology of the occlusion.

Endovascular treatment for anterior cerebral artery occlusions

BACKGROUND

We sought to examine the feasibility, safety and preliminary efficacy of anterior cerebral artery (ACA) occlusions in patients undergoing endovascular treatment.

METHODS

Four hundred five consecutive patients with large-vessel occlusion treated with endovascular treatment were analysed to identify all patients with acute ACA occlusion who underwent endovascular treatment.

RESULTS

Twenty had ACA occlusion (primary ACA occlusion: 9, rescue ACA occlusion: 11), 395 patients had other occlusions (internal carotid artery and MCA). The median [IQR] mRS score in the third month was significantly higher in the ACA-rescue occlusion group versus the ACA-primary occlusion group. The rate of haematoma in patients with ACA-occlusions was significantly higher compared with the ACA-primary occlusion group. Moreover, the three-month mortality rate was higher in patients with ACA-rescue than the patients with ACA-primary.

CONCLUSIONS

Although endovascular treatment can be considered in patients with primary ACA occlusions, our data suggest that future clinical trials are needed to determine the efficacy of endovascular treatment for ACA occlusions. Unfavourable outcomes in our study were considered to occur in the rescue ACA occlusions.

Acute intracranial internal carotid artery occlusion: Extension and location of the thrombus as an influencing factor in Computed Tomography angiography findings

Purpose

Acute intracranial internal carotid artery (ICA) occlusion can mimic an extracranial affectation on Computed Tomography angiography (CTA). This fact could be explained by the extension of the thrombus in the ICA concerning its arterial branches. This study aims to determine how this factor may influence imaging findings.

Methods

A retrospective study was conducted from a single-center database of patients undergoing mechanical thrombectomy due to ICA occlusion between October 2017 and March 2022 (n = 77). Patients with acute intracranial ICA occlusion were included (n = 29) and divided into two groups, according to ICA opacification on CTA: the discernible extracranial ICA or group D, and the pseudo-occlusion or group P. Patency of posterior communicating, anterior choroidal, and ophthalmic arteries on digital subtraction angiography were collected to determine thrombus extension. Sensitivity and specificity were calculated for CTA.

Results

Significant differences were found in DSA between group P (n = 17) and group D (n = 12) in the frequency of patency of major artery branches: the presence of posterior communicating (PCOM) and anterior choroidal arteries (AChA) was observed in 2 patients in group P vs. 10 in group D (p < 0.001); whereas the patency of the ophthalmic artery (OA) was visualized in 10 patients in group P vs. 12 in group D, p = 0.023). For the diagnosis of isolated intracranial ICA occlusion, CTA had a sensitivity of 43.5% and a specificity of 97.2%.

Conclusions

The location and extent of the thrombus in the intracranial ICA concerning major artery branches may influence CTA findings.

Comparison of First-Pass Effect in Aspiration vs. Stent-Retriever for Acute Intracranial ICA Occlusion

The purpose of this study is to evaluate the best endovascular approach (aspiration or stent-retriever) and the impact of stent retriever size and length on clinical and angiographic outcomes in patients with acute intracranial ICA occlusion. We conducted a retrospective analysis of a prospective database of consecutive patients with acute intracranial ICA occlusion undergoing endovascular treatment in four Comprehensive Stroke Center between June-2019 and December-2020. We include 121 patients; Stent-retriever (SR) was used as first technical approach in 107 patients (88.4%) and aspiration was used in 14 patients (11.6%). SR group had higher rate of FPE compared to aspiration group (29 vs. 0%, p = 0.02). In SR subgroup, treatment highlighted higher FPE in the 6 × 50 SR (37.7%), than in the rest of the SR which are 21.2% (4–5 mm size and 20–50 mm length SR) and 19% (6 mm size and 25–40 mm length SR), but it was not found to be statistically significant. There were no other significant differences across the groups regarding primary angiographic or clinical outcomes. In our intracranial ICA occlusion series, stent retrievers were superior to direct aspiration in obtaining FPEs and mFPEs, and longer devices achieved better results with no statistically significant difference. Further studies evaluating the effects of different ICA clot removal approaches are warranted to confirm these results.

Functional Aplasia of the Contralateral A1 Segment Influences Clinical Outcome in Patients with Occlusion of the Distal Internal Carotid Artery

Background: The importance of an A1 aplasia remains unclear in stroke patients. In this work, we analyze the impact of an A1 aplasia contralateral to an acute occlusion of the distal internal carotid artery (ICA) on clinical outcomes. Methods: We conducted a retrospective study of consecutive stroke patients treated with mechanical thrombectomy at 12 tertiary care centers between January 2015 and February 2021 due to an occlusion of the distal ICA. Functional A1 aplasia was defined as the absence of A1 or hypoplastic A1 (>50% reduction to the contralateral site). Functional independence was measured by the modified Rankin Scale (mRS ≤ 2). Results: In total, 81 out of 1068 (8%) patients had functional A1 aplasia contralateral to distal ICA occlusion. Patients with functional contralateral A1 aplasia were more severely affected on admission (median NIHSS 18, IQR 15−23 vs. 17, IQR 13−21; aOR: 0.672, 95% CI: 0.448−1.007, p = 0.054) and post-interventional ischemic damage was larger (median ASPECTS 5, IQR 1−7, vs. 6, IQR 3−8; aOR: 1.817, 95% CI: 1.184−2.789, p = 0.006). Infarction occurred more often within the ipsilateral ACA territory (20/76, 26% vs. 110/961, 11%; aOR: 2.482, 95% CI: 1.389−4.437, p = 0.002) and both ACA territories (8/76, 11% vs. 5/961, 1%; aOR: 17.968, 95% CI: 4.979−64.847, p ≤ 0.001). Functional contralateral A1 aplasia was associated with a lower rate of functional independence at discharge (6/81, 8% vs. 194/965, 20%; aOR: 2.579, 95% CI: 1.086−6.122, p = 0.032) and after 90 days (5/55, 9% vs. 170/723, 24%; aOR: 2.664, 95% CI: 1.031−6.883, p = 0.043). Conclusions: A functional A1 aplasia contralateral to a distal ICA occlusion is associated with a poorer clinical outcome.

Initial Clinical Experience of Repeat Thrombectomy with a Retrieval Stent (RTRS) with Continuous Proximal Flow Arrest by Balloon Guide Catheter for Acute Intracranial Carotid Occlusion

Background

Balloon guide catheters (BGCs) have good performance in terms of radiological outcomes in acute ischemic thrombectomy. It is not uncommon for BGCs to be blocked by thrombi, especially in cases with acute intracranial internal carotid artery (ICA) occlusion. Our initial experience using repeat thrombectomy with a retrieval stent (RTRS) with continuous proximal flow arrest by BGC for acute intracranial ICA occlusion is presented.

Methods

In patients with acute intracranial ICA occlusion treated with RTRS, clinical data, including the National Institutes of Health Stroke Scale (NIHSS) score at admission and modified Rankin Scale (mRS) score at 90 days, and procedural data, including the Extended treatment in Cerebral Infarction (eTICI) score, procedural time, and complications, were analyzed.

Results

Thirty-two consecutive patients (12 men (37.5%); mean age: 73 years) were treated with RTRS using a BGC. The median NIHSS score was 19. The median puncture-to-reperfusion time was 46 minutes (range: 22-142 minutes). All patients were successfully revascularized; eTICI 2c or better recanalization was achieved in 30 (93.8%) patients. No procedure-related complications or symptomatic intracranial hemorrhage occurred. Two cases (6.3%) had distal emboli, but none had emboli to the anterior cerebral artery. Fourteen patients (43.8%) achieved a good outcome with an mRS score of 0-2 at 90 days, and 8 patients (25.0%) died.

Conclusions

In patients with intracranial ICA occlusion, RTRS with proximal flow arrest by BGC is effective and safe, achieving good clinical and angiographic outcomes. This method may reduce the incidence of distal emboli in thrombectomy with stent retrievers.

Mechanical Thrombectomy in Acute Terminal Internal Carotid Artery Occlusions Using a Large Manually Expandable Stentretriever (Tiger XL Device): Multicenter Initial Experience

Background: The recently introduced Tigertriever XL Device for treatment of cerebral vessel occlusions combines manual adjustability and maximum length in one device. In this study, we report our initial experience with the Tigertriever XL in terminal ICA occlusions. Methods: Retrospective multicenter analysis of acute terminal ICA occlusions treated by mechanical thrombectomy using the Tigertriever XL Device. Results: 23 patients were treated using the Tigetriever XL due to an acute occlusion of the terminal ICA. The overall successful reperfusion rate after a median of two maneuvers using the Tigertriever XL Device was 78.3% (mTICI 2b-3). In 43.5% (10/23) additional smaller devices were applied to treat remaining occlusions in downstream territories, which resulted in a final successful reperfusion rate of 95.7%. Device related complications did not occur. Two symptomatic intracerebral hemorrhages (sICH) were observed. Conclusions: The Tigertriever XL Device might be a helpful tool in the treatment of ICA terminus occlusions with large clot burden resulting in high reperfusion rates. This is mainly related to the manual adjustability of the device combined with the maximum length.