Site and Rate of Occlusive Disease in Cervicocerebral Arteries: A CT Angiography Study of 2209 Patients with Acute Ischemic Stroke

Classification and management strategy of spontaneous carotid artery dissection

OBJECTIVE

Spontaneous carotid artery dissections (sCADs) are the common cause of stroke in middle-aged and young people. There is still a lack of clinical classification to guide the management of sCAD. We reviewed our experience with 179 patients with sCAD and proposed a new classification for sCAD with prognostic and therapeutic significance.

METHODS

This is a retrospective review of prospectively collected data from June 2018 to June 2023 of patients with sCAD treated at a large tertiary academic institution in an urban city in China. Based on imaging results, we categorize sCAD into four types: type Ⅰ, intramural hematoma or dissection with <70% luminal narrowing; type Ⅱ, intramural hematoma or dissection with ≥70% luminal narrowing; type Ⅲ, dissecting aneurysm; type ⅣA, extracranial carotid artery occlusion; and type ⅣB, tandem occlusion. We compared the clinical data and prognostic outcomes among various types of sCADs.

RESULTS

A total of 179 patients and 197 dissected arteries met the inclusion criteria. The mean age of the 179 patients with sCAD was 49.5 years, 78% were male, and 18 patients (10%) had bilateral sCAD. According to our classification, there were 56 type Ⅰ (28.4%), 50 type Ⅱ (25.4%), 60 type Ⅲ (30.5%), and 31 type Ⅳ (15.7%) dissections. During a mean hospitalization length of 11.4 ± 47.0 days, there were nine recurrent strokes (4.6%) after medical treatment, two type Ⅲ dissections (1.0%), seven type Ⅳ dissections (3.6%), all ipsilateral, and one death. Overall, there were seven (3.6%, 1 type Ⅰ dissection, 3 type Ⅱ dissections, 2 type Ⅲ dissections, and 1 type Ⅳ dissection) recurrent strokes and three (1.5%, all type Ⅲ dissections) recurrent transient ischemic attacks in patients treated with just medical therapy during the follow-up period, all ipsilateral, with a mean follow-up of 26 months (range, 3-59 months). These patients did not undergo further intervention due to the high difficulty associated with endovascular treatment (EVT) or the mild nature of recurrent cerebral ischemic symptoms. Twenty-nine type I dissections (51.8%) were completely recanalized after antithrombotic therapy. A total of 19 type II dissections (38%) and 44 type III dissections (73%) received EVT for persistent flow-limited dissections, enlargement of dissecting aneurysms, or aggravation of neurological symptoms despite antithrombotic therapy. Type Ⅳ dissections are more likely to lead to the occurrence of ischemic stroke and presented with more severe symptoms. Eight type IVB dissections (33%) received acute phase intervention due to distal thromboembolism or aggravation of neurological symptoms after medical treatment. In terms of cerebral ischemic events and mortality, there were no statistically significant differences among the four types of sCAD (all P > .05). Favorable outcome was achieved in 168 patients (93.9%).

CONCLUSIONS

This study proposed a novel and more comprehensive classification method and the modern management strategy for sCAD. Antithrombotic therapy is beneficial to reduce the risk of recurrent stroke for stable sCAD. Non-emergent EVT can be an alternative therapeutic approach for patients who meet indications as in type II to IVA dissections. Urgent procedure with neurovascular intervention is necessary for some type IVB dissections. The short-term results of EVT for sCAD are encouraging, and long-term device-related and functional outcomes should undergo further research.

Auditing the Findings of Computed Tomographic Angiographic Examinations Using 160-Slice Scanner: Analysis of 5-Year Experiences from Northwestern Nigeria

Background

Computed tomographic angiography (CTA) is a promising tool for the rapid characterisation of the anatomy and structural lesions of the vascular system.

Aim/Objectives

The aims/objectives of the study were to determine the frequency and pattern of vascular lesions in northern Nigeria. We also set to determine the agreement between clinical and CTA diagnosis of vascular lesions.

Materials and Methods

We study patients that had CTA studies over a 5-year period. In total, 361 patients were referred for CTA, but only the records of 339 of them were retrieved and analysed. The information about patients' characteristics, clinical diagnosis, and the findings on CTA was also retrieved and analysed. The categorical data results were expressed as proportions and percentages. The Cohen's kappa coefficient (κ statistic) was used to determine the agreement between the clinical and CTA findings. A P value of <0.05 was considered statistically significant.

Results

The mean (standard deviation) age of the subjects was 49.3 (17.9) years with a range of 1-88 years, consisting of 138 (40.7%) females. Up to 223 patients had various abnormalities on CTA. There were 27 (8.0%) cases of aneurysms, eight (2.4%) cases of arteriovenous malformations, and 99 (29.2%) cases of stenotic atherosclerotic disease. There was a significant agreement between the clinical diagnosis and corresponding findings on CTA showed for intracranial aneurysms (k = 15.0%; P < 0.001), for pulmonary thromboembolism (k = 4.3%; P < 0.001), and for coronary artery disease (k = 34.5%; P < 0.001).

Conclusions

The study found that close to 70% of the patients referred for CTA have abnormal findings, out of which stenotic atherosclerosis and aneurysm are the common findings. Our findings highlighted the diagnostic value of CTA variety of clinical conditions and underscored the prevalence of many vascular lesions in our environment, which hitherto were regarded as uncommon.

Ischemic stroke on hormonal contraceptives: Characteristics, mechanisms and outcome

Introduction

Systemic contraceptives increase the risk of ischemic stroke but little is known about the characteristics, mechanisms and long-term outcome post stroke of patients on hormonal contraception. We sought to To assess characteristics and outcome of acute ischemic stroke (AIS) in young women using systemic hormonal contraceptives (SHC) and compare them to strokes in non-contraceptive users.

Patients and methods

Using the Acute STroke Registry and Analysis of Lausanne (ASTRAL), we analyzed demographics, risk factors, clinical, radiological and treatment data of consecutive female patients of <50 years between 2003 to 2015. We compared groups with and without SHC in a logistic regression analysis.

Results

Of the 179 female patients of <50 years during the observation period, 57 (39.6%) used SHC, 71.9% of whom, a combined oral contraceptive pill. On logistic regression contraceptive users were significantly younger but had comparable stroke severity. They had less migraine with aura and tobacco use, and more hyperlipidaemia. Also, contraceptive users had significantly less intra and extracranial stenosis and occlusion on arterial imaging, but more focal hypoperfusion on CT-perfusion. Undetermined mechanism of stroke was more frequent with SHC users, whereas rare mechanisms were more frequent in non-users. The contraceptive user group had a more favourable adjusted 12-month outcome with significantly fewer ischemic recurrences after stopping systemic contraception in all.

Conclusion

Contraceptive users with ischemic strokes are younger and have lesser tobacco use and migraine with aura and more hyperlipidemia. Their stroke mechanism is more often undetermined using a standardised work-up, and their adjusted long-term outcome is more favourable with less stroke recurrence.

Superficial Temporal Artery-Posterior Cerebral Artery Bypass for the Treatment of Chronic Basilar Artery Occlusion

OBJECTIVE

To investigate the effect of superficial temporal artery-posterior cerebral artery (STA-PCA) bypass on chronic basilar artery occlusion (CBAO).

METHODS

A total of 4 patients who underwent STA-PCA bypass between January 2018 and October 2019 were enrolled in this study. Cerebral blood perfusion, ischemic events, STA diameter and blood flow changes, modified Rankin scale score (mRS), and National Institutes of Health Stroke Scale (NIHSS) score changes were recorded before and after bypass surgery.

RESULTS

The average time from basilar artery occlusion (confirmed by cerebral angiography or computed tomography angiography) to operation was 76 ± 38.89 days (range: 30-120 days). Average scores on the NIHSS were 6.8 ± 1.26 (5-8) and 5.2 ± 2.06 (3-7) before and after treatment, respectively. mRS scores averaged 1.8 ± 0.5 (1-2) and 1.5 ± 0.58 (1-2) points, respectively. There were no obvious complications or further stroke during the follow-up. The STA diameter and flow rate were significantly increased at 12 months after operation (P < 0.05).

CONCLUSIONS

STA-PCA bypass can improve cerebral blood flow perfusion in CBAO patients. The diameter and flow of the superficial temporal artery can be increased to meet the demand of blood supply.

Endovascular Treatment of Acute Ischemic Stroke

PURPOSE OF REVIEW

This article reviews the actual indications for mechanical thrombectomy in patients with acute ischemic stroke and how the opportunities for endovascular therapy can be expanded by using the concept of clinical-imaging or perfusion-imaging mismatch (as a surrogate for salvageable tissue) rather than time of ischemia.

RECENT FINDINGS

Six randomized controlled trials undoubtedly confirmed the benefits of using endovascular thrombectomy on the clinical outcome of patients with stroke with large vessel occlusion within 6 hours from symptom onset compared with those receiving only standard medical care. In a meta-analysis of individual patient data, the number needed to treat with endovascular thrombectomy to reduce disability by at least one level on the modified Rankin Scale for one patient was 2.6. Recently, the concept of "tissue window" versus time window has proved useful for selecting patients for mechanical thrombectomy up to 24 hours from symptom onset. The DAWN (DWI or CTP Assessment With Clinical Mismatch in the Triage of Wake-Up and Late Presenting Strokes Undergoing Neurointervention) trial included patients at a median of 12.5 hours from onset and showed the largest effect in functional outcome ever described in any acute stroke treatment trial (35.5% increase in functional independence). In DEFUSE 3 (Diffusion and Perfusion Imaging Evaluation for Understanding Stroke Evolution 3), patients treated with mechanical thrombectomy at a median of 11 hours after onset had a 28% increase in functional independence and an additional 20% absolute reduction in death or severe disability.

SUMMARY

For patients with acute ischemic stroke and a large vessel occlusion in the proximal anterior circulation who can be treated within 6 hours of stroke symptom onset, mechanical thrombectomy with a second-generation stent retriever or a catheter aspiration device should be indicated regardless of whether the patient received treatment with intravenous (IV) recombinant tissue plasminogen activator (rtPA) in patients with limited signs of early ischemic changes on neuroimaging. Two clinical trials completely disrupted the time window concept in acute ischemic stroke, showing excellent clinical outcomes in patients treated up to 24 hours from symptom onset. Time of ischemia is, on average, a good biomarker for tissue viability; however, the window of opportunity for treatment varies across different individuals because of a range of compensatory mechanisms. Adjusting time to the adequacy of collateral flow leads to the concept of tissue window, a paradigm shift in stroke reperfusion therapy.

Association Between Occlusion Type and Etiology of Acute Intracranial Large Artery Occlusion

Objective: To investigate the diagnostic efficiency of truncal-type occlusion and branching-site occlusion in determining the etiology of intracranial large artery occlusion related acute ischemic stroke (AIS).

Methods: Patients with intracranial large artery occlusion related AIS who received stent retriever (SR) thrombectomy from November 2014 to June 2019 were included in the study. All patients underwent angiography before SR thrombectomy, which was used to evaluate the occlusion type. Differences in the distribution of occlusion types in intracranial atherosclerosis (ICAS) and embolism were assessed, and the diagnostic indicators, including the area under the ROC curve (AUC), sensitivity, and specificity were calculated.

Results: Of the 115 AIS patients with intracranial large artery occlusion, 42 were classified as having ICAS, and 73 having an embolism. In the ICAS group, branching-site occlusion was responsible for 3 (7%) cases and truncal-type occlusion for 39 (93%) cases, while in the embolism group, branching-site occlusion was responsible for 66 (90%) cases and truncal-type occlusion for 7 (10%) cases; the difference was statistically significant (all P < 0.01). The AUC for ICAS predicted by truncal-type occlusion was 0.916, with a sensitivity of 92.86%, and specificity of 90.41%.

Conclusion: Truncal-type occlusion showed a high predictability of ICAS. Determine the etiology of intracranial large artery occlusion related AIS before SR thrombectomy may be most helpful in setting up optimal endovascular treatment strategies.

Standard Diffusion-Weighted Imaging in the Brain Can Detect Cervical Internal Carotid Artery Dissections

BACKGROUND AND PURPOSE

The ICA is the most common site of cervical artery dissection. Prompt and reliable identification of the mural hematoma is warranted when a dissection is clinically suspected. The purpose of this study was to assess to capacity of a standard DWI sequence acquired routinely on the brain to detect dissecting hematoma related to cervical ICA dissections.

MATERIALS AND METHODS

This was a retrospective study of a cohort of 110 patients younger than 55 years of age (40 women; mean age, 46.79 years) admitted at the acute phase of a neurologic deficit, headache, or neck pain and investigated by at least a standard 3T diffusion-weighted sequence of the brain. Among them were 50 patients (14 women; mean age, 46.72 years) with subsequently confirmed ICA dissection. In the whole anonymized cohort, both a senior and junior radiologist separately assessed, on the DWI sequences only, the presence of a crescent-shaped or circular hypersignal projecting on the subpetrosal segment of the ICA arteries, assuming that it would correspond to a mural hematoma related to an ICA dissection.

RESULTS

The senior radiologist found 46 subpetrosal hyperintensities in 43/50 patients with ICA dissection and none in patients without dissection (sensitivity, 86%; specificity, 100%). The junior radiologist found 48 subpetrosal hyperintensities in 45/50 patients with dissection and none in patients without dissection (sensitivity, 90%; specificity, 100%).

CONCLUSIONS

In our cohort, a standard DWI sequence performed on the brain at the acute phase of a stroke or for a clinical suspicion of dissection detected nearly 90% of cervical ICA dissections.

Associated Factors and Long-Term Prognosis of 24-Hour Worsening of Arterial Patency After Ischemic Stroke

Background and Purpose- Early arterial recanalization in acute ischemic stroke is strongly associated with better outcomes. However, early worsening of arterial patency was seldom studied. We investigated potential predictors and long-term prognosis of worsening of arterial patency at 24 hours after stroke onset. Methods- Patients from the Acute Stroke Registry and Analysis of Lausanne registry including admission and 24-hour vascular imaging (computed tomography or magnetic resonance angiography) were included. Worsening of arterial patency was defined as a new occlusion and significant stenosis in any extracranial or intracranial artery, comparing 24 hours with admission imaging. Variables associated with worsening of arterial patency were assessed by stepwise multiple logistic regression. The impact of arterial worsening on 3-month outcome was investigated with an adjusted modified Rankin Scale shift analysis. Results- Among 2152 included patients, 1387 (64.5%) received intravenous thrombolysis and endovascular treatment, and 65 (3.0%) experienced 24-hour worsening of arterial patency. In multivariable analysis, history of hypertension seemed protective (adjusted odds ratio [aOR], 0.45; 95% CI, 0.27-0.75) while higher admission National Institutes of Health Stroke Scale (aOR, 1.06; 95% CI, 1.02-1.10), intracranial (aOR, 4.78; 95% CI, 2.03-11.25) and extracranial stenosis (aOR, 3.67; 95% CI, 1.95-6.93), and good collaterals (aOR, 3.71; 95% CI, 1.54-8.95) were independent predictors of worsening of arterial patency. Its occurrence was associated with a major unfavorable shift in the distribution of the modified Rankin Scale at 3 months (aOR, 5.97; 95% CI, 3.64-9.79). Conclusions- Stroke severity and admission vascular imaging findings may help to identify patients at a higher risk of developing worsening of arterial patency at 24 hours. The impact of worsening of arterial patency on long-term outcome warrants better methods to detect and prevent this early complication.

Radiological Eye Deviation as a Predictor of Large Vessel Occlusion in Acute Ischaemic Stroke

BACKGROUND

Detection of large vessel occlusion (LVO) is required for endovascular therapy in acute ischemic stroke (AIS) but CT angiography (CTA) is not always performed at primary stroke centers. Eye deviation on CT brain has been associated with improved stroke detection, but comparisons with angiographic status have been limited. This study sought to determine if radiological eye deviation was associated with LVO.

METHODS

All AIS patients given intravenous thrombolysis who had acute CTA performed in 2 stroke units were reviewed over 2013-2015 for the presence of LVO. Eye deviation was determined by 2 clinicians blinded to LVO status. Logistic regression was performed to determine which factors predicated LVO.

RESULTS

Total 195 AIS patients with acute CTA were identified; 124 (64%) had LVO. Median age was 72 (IQR 64-82) years, median National Institutes of Health Stroke Scale (NIHSS) was 12 (IQR 7-14). LVO patients had a higher NIHSS (15 versus 7, p < .01) and were more likely to have eye deviation on CT brain (71% versus 22.5%, p < .01). Logistic regression confirmed NIHSS score and eye deviation were associated with LVO, with odds ratios of 1.15 (per point) and 5.13 respectively. NIHSS less than equal to 11 gave greatest sensitivity (78.5%) and specificity (76.1%) for LVO with a positive predictive value of 84.7%. Eye deviation was similar with sensitivity 71%, specificity 77.5%, and 84.6%.

CONCLUSIONS

Eye deviation on CT brain is strongly associated with LVO. Presence of eye deviation on CT should alert clinicians to probability of LVO and for formal angiographic testing if not already performed.

Efficacy and safety of endovascular treatment in acute ischemic stroke due to cervical artery dissection: A 15-year consecutive case series

Background

Limited observational data are available on endovascular treatment in acute ischemic stroke due to cervical artery dissection. Three studies comparing endovascular treatment with standard medical therapy or intravenous thrombolysis in cervical artery dissection-related acute ischemic stroke did not demonstrate superiority of endovascular treatment. Efficacy and the choice of endovascular treatment technique in this setting remain to be established.

Aims

To assess the potential efficacy and safety of endovascular treatment compared to intravenous thrombolysis alone or to no revascularization treatment in our center.

Methods

We selected all consecutive patients with cervical artery dissection-related acute ischemic stroke and intracranial occlusion from the Acute STroke Registry and Analysis of Lausanne between 2003 and 2017. We compared clinical and neuroimaging data of patients treated by endovascular treatment versus patients receiving intravenous thrombolysis or patients without revascularization treatment. Safety analysis included symptomatic intracranial hemorrhage, major radiological hemorrhages (parenchymal hematoma 1, parenchymal hematoma 2, and subarachnoid hemorrhage) and mortality within seven days. We assessed favorable clinical outcome (modified Rankin Scale 0-2) at three months using a binary logistic regression model.

Results

Of the 109 patients included, 24 had endovascular treatment, 38 received intravenous thrombolysis alone, and 47 had no revascularization treatment. Endovascular treatment patients had a higher rate of recanalization at 24 h. Major radiological hemorrhages occurred more often in endovascular treatment patients (all with bridging therapy) than in patients without revascularization treatment (p = 0.026), with no differences in symptomatic intracranial hemorrhage or mortality within seven days. Favorable clinical outcome at three months did not differ between groups (endovascular treatment versus intravenous thrombolysis p = 0.407; endovascular treatment versus no revascularization treatment p = 0.580).

Conclusions

In this single-center cohort of cervical artery dissection-related acute ischemic stroke with intracranial occlusion, endovascular treatment with prior intravenous thrombolysis may increase the risk of major radiological but not symptomatic intracranial hemorrhage. Despite the lack of clear superiority in our cohort, endovascular treatment should currently not be withheld in these patients.