DWI-pc-ASPECT score in basilar artery occlusion: is 6 points or less always indicative of a bad outcome?

Efficacy of Endovascular Thrombectomy in Acute Basilar Artery Occlusion with Low PC-ASPECTS: A Nationwide Prospective Registry-Based Study

OBJECTIVE

We evaluated the efficacy of endovascular thrombectomy (EVT) on the functional outcome of patients with acute basilar artery occlusion and low posterior circulation acute stroke prognosis early computed tomography score (PC-ASPECTS).

METHODS

We identified patients with acute ischemic stroke due to basilar artery occlusion and PC-ASPECTS of 6 or less, presenting within 24 h between August 2008 and April 2022. The primary outcome was a favorable functional outcome, defined as a modified Rankin Scale (mRS) score of 0-3 at 90 days. The secondary outcomes included an mRS score of 0-2, a favorable shift in the ordinal mRS scale, the occurrence of symptomatic intracranial hemorrhage (sICH), and mortality at 90 days. We compared the outcome of patients treated with EVT and those without EVT, using the inverse probability of treatment weighting methods.

RESULTS

Out of 566 patients, 55.5% received EVT. In the EVT group, 106 (33.8%) achieved favorable outcomes, compared to 56 patients (22.2%) in the conservative group. EVT significantly increased the likelihood of achieving a favorable outcome compared to conservative treatment (relative risk [RR] 1.39, 95% confidence interval [CI], 1.11-1.74, p = 0.004). EVT was associated with a favorable shift in the mRS (RR 1.85, 95% CI, 1.49-2.29, p < 0.001) and reduced mortality without an increase in the risk of sICH. It did not have an impact on achieving an mRS score of 0-2.

INTERPRETATION

Patients with acute basilar artery occlusion and a PC-ASPECTS of 6 or less might benefit from EVT without an increasing sICH. ANN NEUROL 2024;95:788-799.

Automated ASPECTS calculation may equal the performance of experienced clinicians: a machine learning study based on a large cohort

OBJECTIVES

The Alberta Stroke Program Early CT Score (ASPECTS) is a semi-quantitative method to evaluate the severity of early ischemic change on non-contrast computed tomography (NCCT) in patients with acute ischemic stroke (AIS). In this work, we propose an automated ASPECTS method based on large cohort of data and machine learning.

METHODS

For this study, we collected 3626 NCCT cases from multiple centers and annotated directly on this dataset by neurologists. Based on image analysis and machine learning methods, we constructed a two-stage machine learning model. The validity and reliability of this automated ASPECTS method were tested on an independent external validation set of 300 cases. Statistical analyses on the total ASPECTS, dichotomized ASPECTS, and region-level ASPECTS were presented.

RESULTS

On an independent external validation set of 300 cases, for the total ASPECTS results, the intraclass correlation coefficient between automated ASPECTS and expert-rated was 0.842. The agreement between ASPECTS threshold of ≥ 6 versus < 6 using a dichotomized method was moderate (κ = 0.438, 0.391-0.477), and the detection rate (sensitivity) was 86.5% for patients with ASPECTS threshold of ≥ 6. Compared with the results of previous studies, our method achieved a slight lead in sensitivity (67.8%) and AUC (0.845), with comparable accuracy (78.9%) and specificity (81.2%).

CONCLUSION

The proposed automated ASPECTS method driven by a large cohort of NCCT images performed equally well compared with expert-rated ASPECTS. This work further demonstrates the validity and reliability of automated ASPECTS evaluation method.

CLINICAL RELEVANCE STATEMENT

The automated ASPECTS method proposed by this study may help AIS patients to receive rapid intervention, but should not be used as a stand-alone diagnostic basis.

KEY POINTS

NCCT-based manual ASPECTS scores were poorly consistent. Machine learning can automate the ASPECTS scoring process. Machine learning model design based on large cohort data can effectively improve the consistency of ASPECTS scores.

Endovascular thrombectomy for basilar-artery occlusion: A meta-analysis with trial sequential analysis

Background and purpose

Basilar-artery occlusion (BAO) usually accounts for devastating neurologic sequelae, poor prognosis, and even death. While endovascular thrombectomy (EVT) is the most successful treatment for anterior circulation stroke with large vessel occlusion, its effectiveness in treating acute BAO is still debatable. Our aim is to compare the efficacy and safety between EVT and conservative medical treatment (CMT) in BAO.

Methods

Up until May 2022, relevant literature was gathered using searches in Embase, PubMed, and the Cochrane Library. The primary outcomes were defined as good functional outcome (modified Rankin Scale 0-2) and favorable functional outcome (modified Rankin Scale 0-3) at 3 months between EVT and CMT groups. The secondary outcomes included mortality at 3 months, symptomatic intracerebral hemorrhage (ICH), and any ICH.

Results

Eight studies involving 3733 patients with BAO were enrolled 2573 individuals underwent EVT, and the remaining 1160 patients received CMT. Compared with CMT, EVT achieved more favorable functional outcome (odds ratio (OR) 1.26, 95% CI 1.03-1.55, I2 = 54%, p = 0.05) in BAO. The good functional outcome showed a similar tendency (OR 1.23, 95% CI 0.97-1.57, I2 = 63%, p = 0.02) as well. EVT decreased mortality at 3 months (OR 0.81, 95% CI 0.70-0.93, I2 = 31 %, p = 0.19), although having a tendency to cause symptomatic ICH (OR 2.91, 95% CI 1.38-6.18, I2 = 22 %, p = 0.27).

Conclusions

EVT in BAO provides superior functional outcomes and less mortality compared with CMT. Even though EVT has the propensity to cause symptomatic ICH, EVT nevertheless improved posterior circulation stroke.

Basilar artery occlusion: A review of clinicoradiologic features, treatment selection, and endovascular techniques

Basilar artery occlusion (BAO) is an infrequent but often fatal subtype of stroke. Predicting outcomes and selecting patients for endovascular therapy (EVT) remains challenging. Advances in neuroimaging and the development of prognostic scoring systems have augmented clinical decision-making over time. Recent randomized trials, BEST (Basilar Artery Occlusion Endovascular Intervention vs. Standard Medical Treatment), BASICS (Basilar Artery International Cooperation Study), BAOCHE (Basilar Artery Occlusion CHinese Endovascular Trial) and ATTENTION (Endovascular Treatment for Acute Basilar Artery Occlusion), compared EVT and medical management for patients with BAO. These trials yielded mixed results. The former two suggested unclear benefit while the latter two supported a benefit of EVT. While all had limitations, most providers agree caution should be exercised when excluding patients from EVT who may stand to benefit. Further studies are therefore needed to determine the effectiveness, safety, selection criteria, and optimal technical approach for EVT among patients with BAO. Hyperacute-phase advanced imaging can offer several benefits to aid decision making. It is reasonable to exclude patients with low National Institutes of Health Stroke Scale (NIHSS), large imaging-proven cores, and evidence of perforator occlusion by branch atheromatous disease. Herein, we review the clinical presentation, imaging work-up, treatments, and clinical outcomes for BAO, while highlighting knowledge gaps in treatment selection and technique.

Endovascular therapy for acute stroke with a large infarct core: A systematic review and meta-analysis

OBJECTIVE

In this meta-analysis, we aimed to investigate the efficacy and safety of endovascular treatment (EVT) for acute ischemic stroke (AIS) patients with large core infarct.

METHODS

Three online databases of Web of Science, PubMed and Scopus were systematically searched. Original studies which evaluated AIS participants with large core infarction who underwent EVT were included. R statistical software was used for statistical analyses. Effect sizes were presented with odds ratios (ORs) with their 95% confidence intervals (CIs). The effect sizes were pooled using random effects modeling.

RESULTS

Including 47 studies and 15,173 patients, this meta-analysis showed that compared with medical management (MM), EVT was significantly associated with decreased odds of mortality (0.67, 95% CI: 0.51-0.87) and increased odds of favorable outcomes, including a modified Rankin Scale of 0-3 (2.36, 95% CI: 1.69-3.291) and of 0-2 (3.54, 95% CI: 1.96-6.4) in 90 days and remarkable improvement in National Institutes of Health Stroke Scale within 48 h after the procedure (3.6, 95% CI:1.32-9.79). Besides, there was a higher chance of intracranial hemorrhage (ICH) development (1.88, 95% CI: 1.32-2.68) but not symptomatic ICH (1.34, 95% CI: 0.78-2.31) in those who underwent EVT.

CONCLUSION

Our study suggests that EVT might be an effective and relatively safe treatment option for the treatment of AIS patients with large vessel occlusion who have large core infarcts, although more large-scale trials are needed to consolidate the results and to make inclusion criteria and the patient selection process clearer.

Imaging predictors of clinical outcomes after endovascular treatment in MRI-selected patients with acute basilar artery occlusion

PURPOSE

We aimed to investigate the impact of baseline infarct area and collateral status (CS), which are imaging predictors of clinical outcome following stroke, after endovascular treatment (EVT) in MRI-selected patients with acute basilar artery occlusion (BAO).

METHODS

Patients with acute BAO who underwent EVT within 24 h after stroke from December 2013 to February 2021 were included in this retrospective, multicenter, observational study. The baseline infarct area was evaluated by the posterior circulation of Acute Stroke Prognosis Early Computed Tomography Score (pc-ASPECTS) using diffuse-weighted imaging (DWI), and CS was assessed by measuring the computed tomography angiography of the basilar artery (BATMAN) score and the posterior circulation collateral score (PC-CS) using magnetic resonance angiography (MRA). A Good outcome was defined as a modified Rankin scale score ≤ 3 at 3 months. For each imaging predictor, a multivariate logistic regression analysis was performed to evaluate its impact on good outcomes.

RESULTS

A total of 86 patients were analyzed, and 37 (43.0%) had a good outcome. The latter showed significantly higher pc-ASPECTS than those without good outcomes. In multivariate analyses, a pc-ASPECTS ≥ 7 was significantly associated with good outcomes (OR, 2.98 [95% CI, 1.10-8.13], P = 0.032), while PC-CS ≥ 4 (OR, 2.49 [95% CI, 0.92-6.74], P = 0.073) and BATMAN score ≥ 5 (OR, 1.51 [95% CI, 0.58-3.98], P = 0.401) were not.

CONCLUSIONS

In MRI-selected patients with acute BAO, pc-ASPECTS on DWI was an independent predictor of clinical outcomes after EVT, while the MRA-based CS assessments were not.

Vertebral to Basilar Thrombus Migration Post Intravenous Thrombolysis

Recombinant tissue plasminogen activator improves outcomes in acute ischemic stroke. Alteplase may result in thrombus migration (TM) distally to a critical arterial supply that can worsen perfusion to eloquent brain tissue. Alteplase-related stroke recanalization and clot migration in vertebral artery (VA) occlusion whereby the clot migrates to the basilar artery (BA) may be harmful. We identified seven subjects with isolated symptomatic vertebral occlusion. Two cases suffered early neurologic deterioration due to TM from VA to BA following alteplase. Precautionary transfer to thrombectomy centers may be warranted in alteplase-treated symptomatic VA occlusions in case of migration to basilar occlusion.

Tmax profile in computed tomography perfusion-based RAPID software maps influences outcome after mechanical thrombectomy in patients with basilar artery occlusion

BACKGROUND

Computed tomography perfusion (CTP) parameters have been shown to have predictive value for functional outcomes of patients with basilar artery occlusion (BAO). We report the predictive value of CTP-based software (CTP-Rapid Processing of Perfusion and Diffusion (RAPID); iSchemia View) for functional outcomes of patients with BAO after endovascular therapy (EVT).

METHODS

Patients with BAO who underwent EVT were retrospectively analyzed in our center from December 2019 to July 2021. Baseline characteristics and imaging parameters from non-contrast CT, CT angiography (CTA), and CTP-RAPID were collected for analysis.

RESULTS

Among the 55 patients enrolled in this study, 22 (40.0%) achieved a good functional outcome (modified Rankin Scale score ≤3 at 90 days). In the univariate analysis, posterior circulation Alberta Stroke Program Early CT Score, Basilar Artery on CT Angiography score, posterior circulation CTA score, posterior communicating artery deficiency, perfusion deficit volume in time to maximum (Tmax) >4 s, Tmax >6 s, and mismatch volume were associated with functional outcomes (all p<0.05). In the multivariate analysis, perfusion deficit volume in Tmax >6 s (OR 1.011 (95% CI 1.001 to 1.020)) and posterior circulation CTA score (OR 0.435 (95% CI 0.225 to 0.840)) remained independent outcome predictors (all p<0.05).

CONCLUSIONS

Perfusion deficit volume in Tmax >6 s on CTP-RAPID imaging maps and basilar artery on CTA score have potential as functional outcome predictors in patients with BAO after EVT.

Decision-making strategies for reperfusion therapies: navigating through stroke trials gaps

Despite there being a robust amount of literature and numerous randomized clinical trials regarding acute ischemic stroke treatment, the trials have not included some frequent controversial situations for which decision-making strategies are an urgent and unmet need in clinical practice. This article tries to summarize the current evidence about some selected situations (mechanical thrombectomy in low ASPECTS, low NIHSS with proximal occlusion, acute basilar occlusion, distal and medium vessel occlusion, among others), make suggestions on how to approach them in clinical practice and show what to expect in acute stroke research in the near future.

Outcomes of acute basilar artery occlusion-real-world experience in a middle-income country

OBJECTIVES

Our goal was to describe outcomes in a single-center, real-world series of patients with acute basilar artery occlusion in a middle-income country. In addition, we assessed potential outcome predictors.

MATERIAL AND METHODS

Data from 28 patients were retrospectively reviewed. The primary outcome was death until last follow-up. Other outcomes were rates of favorable outcome until last follow-up and rates of intracranial hemorrhage. Outcomes were compared in subgroups according to several variables, including reperfusion (REP group) or no reperfusion (NOREP group) interventions, with chi-squared, Fisher's exact test, or Mann-Whitney tests.

RESULTS

The rate of overall intrahospital death was 46%. Death until last follow-up occurred in 8/17 (47%) in the REP and in 7/11 (63%) of the NOREP group. Favorable outcomes were observed in 35.7% of the patients: 8/17 (47%) in REP and in 2/11 (18.1%) in NOREP. NIH stroke scale scores were significantly lower in patients with favorable outcomes. Intracranial hemorrhage was observed in 6/28 (21.4%) of the patients (all in REP group). Twenty patients were treated with anticoagulants within the first 24 h. No hemorrhage was observed in those treated with enoxaparin, while three occurred in subjects treated with unfractionated heparin.

CONCLUSION

Together with other series, our results underscore the relevance of NIH stroke scale at admission as a prognostic marker, the importance of reperfusion to improve outcomes, and the need of clinical trials to compare the impact of treatment with anticoagulants within first 24 h in basilar artery occlusion.

Effects of and prognostic factors affecting endovascular mechanical thrombectomy of acute vertebrobasilar artery occlusion

PURPOSE

To investigate the clinical outcome and factors affecting the prognosis of endovascular mechanical thrombectomy of acute vertebrobasilar artery occlusion.

MATERIALS AND METHODS

Eighty-three patients with acute vertebrobasilar artery occlusion were treated with endovascular mechanical thrombectomy, and the recanalization rate, clinical outcomes at three months, modified DWI-PC-ASPECTS, and MRA-BATMAN scores were analyzed.

RESULTS

Following acute mechanical thrombectomy, the TICI 2B-3 score was achieved in all patients (100%). At three-month evaluation, 56 (67.5%) patients had good prognosis with the mRS score of 0-2, including 13 (23.2%) patients who had arterial occlusion caused by emboli and 43 (76.8%) who had atherosclerotic stenosis. In analyzing factors affecting the prognosis, a significant difference (P < 0.05) existed between patients with good (mRS 0-2) and poor (mRS 3-6) prognosis in the NIHSS (17.3 vs. 31.2, P = 0.000001), modified DWI-PC-ASPECTS (10.4 vs. 7.8, P = 0.021), and MRA-BATMAN (6.3 vs. 4.6, P = 0.003) scores. Univariate Logistic regression analysis demonstrated NIHS score ≥ 21, modified DWI-PC-ASPECTS score ≤ 8.5, and MRA-BATMAN score ≤ 6.5 to be the risk factors for poor prognosis. Multivariate Logistic regression analysis revealed NIHSS score ≥ 21 as an independent risk factor for poor prognosis.

CONCLUSION

Endovascular mechanical thrombectomy is safe and effective in recanalizing occluded vertebrobasilar artery occlusion, and NIHS score ≥ 21, modified DWI-PC-ASPECTS score ≤ 8.5, and MRA-BATMAN score ≤ 6.5 are the risk factors for poor prognosis.

Basilar artery occlusion presenting as sudden bilateral deafness: a case report

Background

Most sudden-onset hearing loss is due to otolaryngologic- and very rarely to cerebrovascular disease. We report a woman with sudden bilateral sensorineural hearing loss. This case suggests that even in the absence of brainstem or cerebellar signs, magnetic resonance imaging (MRI) and MR angiography (MRA) should be performed since such studies may reveal signs of life-threatening vertebrobasilar artery occlusion.

Case presentation

A 73-year-old Japanese woman with a history of hypertension, hyperlipidemia, and atrial fibrillation who suffered bilateral deafness with vertigo and vomiting was transferred from a local hospital to our department. On admission her consciousness was clear and vertigo was absent. Neurological examination revealed only bilateral sensorineural hearing loss. Head computed tomography (CT) returned no significant findings. The next morning she gradually developed severe drowsiness. Diffusion-weighted MRI demonstrated acute cerebral infarction in the brainstem and bilateral cerebellum; MRA showed basilar artery occlusion due to a cardioembolic thrombus. Revascularization was obtained by endovascular treatment. However, her condition worsened progressively during the following hours. CT revealed new brainstem lesions, massive cerebellar swelling, and obstructive hydrocephalus. She died on the second day after her admission.

Conclusions

When hearing loss is due to vertebrobasilar occlusive disease, the prognosis is very poor. We suggest that vertebrobasilar stroke be suspected in patients with bilateral sensorineural hearing loss who present with risk factors for stroke such as atrial fibrillation and other neurologic signs.

Values of Baseline Posterior Circulation Acute Stroke Prognosis Early Computed Tomography Score for Treatment Decision of Acute Basilar Artery Occlusion

BACKGROUND AND PURPOSE

This study aimed to analyze the impact of baseline posterior circulation Acute Stroke Prognosis Early Computed Tomography Score (pc-ASPECTS) on the efficacy and safety of endovascular therapy (EVT) for patients with acute basilar artery occlusion.

METHODS

The BASILAR was a nationwide prospective registry of consecutive patients with a symptomatic and radiologically confirmed acute basilar artery occlusion within 24 hours of symptom onset. We estimated the effect of standard medical therapy alone (SMT group) versus SMT plus EVT (EVT group) for patients with documented pc-ASPECTS on noncontrast CT, both as a categorical (0-4 versus 5-7 versus 8-10) and as a continuous variable. The primary outcomes included favorable functional outcomes (modified Rankin Scale ≤3) at 90 days and mortality within 90 days.

RESULTS

In total, 823 cases were included: 468 with pc-ASPECTS 8 to 10 (SMT: 71; EVT: 397), 317 with pc-ASPECTS 5 to 7 (SMT: 85; EVT: 232), and 38 with pc-ASPECTS 0 to 4 (SMT: 13; EVT: 25). EVT was associated with higher rate of favorable outcomes (adjusted relative risk with 95% CI, 4.35 [1.30-14.48] and 3.20 [1.68-6.09]; respectively) and lower mortality (60.8% versus 77.6%, P=0.005 and 35.0% versus 66.2%, P<0.001; respectively) than SMT in the pc-ASPECTS 5 to 7 and 8 to 10 subgroups. Continuous benefit curves also showed the superior efficacy and safety of EVT over SMT in patients with pc-ASPECTS ≥5. Furthermore, the prognostic effect of onset to puncture time on favorable outcome with EVT was not significant after adjustment for pc-ASPECTS (adjusted odds ratio, 0.98 [95% CI, 0.94-1.02]).

CONCLUSIONS

Patients of basilar artery occlusion with pc-ASPECTS ≥5 could benefit from EVT. The baseline pc-ASPECTS appears more important for decision making and predicting prognosis than time to EVT. Registration: URL: http://www.chictr.org.cn. Unique identifier: ChiCTR1800014759.

A Meta-Analysis of Prognostic Factors in Patients with Posterior Circulation Stroke after Mechanical Thrombectomy

BACKGROUND

Posterior circulation stroke is characterized by poor prognosis because its optimal thrombolysis "time window" is always missed. After mechanical thrombectomy (MT), the recanalization rate of posterior circulation obstruction is significantly increased, but prognosis remains poor. To best manage patients, prognostic factors are needed to inform MT triaging after posterior circulation stroke.

METHODS

A systematic literature search was done for the period through April 2020. Studies included those with posterior circulation stroke cases that underwent MT. The primary outcome measure in this study was the modified Rankin Scale on day 90.

RESULTS

No outcome differences were found in gender, atrial fibrillation, smoking, and coronary artery disease (OR = 1.07, 95% CI: 0.90-1.28; OR = 1.02, 95% CI: 0.82-1.26; OR = 1.26, 95% CI: 0.94-1.68; and OR = 0.84, 95% CI: 0.58-1.22, respectively). Hypertension, diabetes mellitus, and previous stroke correlated with poorer prognosis (OR = 0.61, 95% CI: 0.48-0.77; OR = 0.60, 95% CI: 0.50-0.73; and OR = 0.74, 95% CI: 0.55-0.99, respectively). However, hyperlipidemia correlated with better prognosis (OR = 1.28, 95% CI: 1.04-1.58).

CONCLUSION

Our analysis indicates that hypertension, diabetes mellitus, or previous stroke correlate with poorer outcomes. Intriguingly, hyperlipidemia correlates with better prognosis. These factors may help inform triage decisions when considering MT for posterior circulation stroke patients. However, large, multicenter, randomized controlled trials are needed to validate these observations.

Presenting NIHSS predicts 90-day functional outcome after mechanical thrombectomy for basilar artery occlusion: A systematic review and meta-analysis

The prediction of outcome after mechanical thrombectomy (MT) of basilar artery occlusion (BAO) remains an area of investigation. The objective of this study was to evaluate the prognostic role of presenting National Institute Health of Stroke Scale (NIHSS) scores in predicting favorable 90-day functional outcome. A survey of 7 electronic databases from inception to May 2020 was conducted following PRISMA guidelines. Articles were screened against pre-specified criteria. Multivariate odds ratios (ORs) for favorable 90-day function outcome (modified Rankin Score 0-2) were extracted and pooled by meta-analysis of proportions with random effects modeling. A total of 10 individual studies satisfied criteria for selection and described a total of 941 BAO patients managed by MT. Analysis revealed 590 (63%) males with a mean age of 66.6 years. The median presenting NIHSS was 19, and 316 (34%) patients were reported to have a favorable functional status 90-days after treatment. Lower presenting NIHSS scores independently and significantly predicted favorable 90-day functional outcome in BAO patients with a pooled OR of 0.89 (95% CI, 0.87-0.92; I² = 18%; P-heterogeneity = 0.28). Meta-regression did not detect any clinical parameter that influenced this trend direction or its significance, and bias assessments were unremarkable. We confirm in this study via a consensus within the literature that the presenting NIHSS score predicts 90-day functional outcome in BAO patients treated by MT. Further, its standardized use allows more meaningful comparisons between interventions and anatomical locations.

Predictive value on diffusion weighted imaging scores for basilar artery occlusion after endovascular treatment

PURPOSE

To assess the predictive value of three scoring systems based on diffusion weighted imaging in basilar artery occlusion patients after endovascular treatment.

METHODS

We analyzed clinical and radiological data of patients with basilar artery occlusion from January 2010 to June 2019, with modified Rankin Scale of 0-2 and 3-6 defined as favorable outcome and unfavorable outcome at three months. Diffusion weighted imaging posterior circulation ASPECTS Score (DWI pc-ASPECT Score), Renard diffusion weighted imaging Score, and diffusion weighted imaging Brainstem Score were used to evaluate the early ischemic changes.

RESULTS

There were a total of 88 basilar artery occlusion patients enrolled in the study after endovascular treatment, with 33 of them getting a favorable outcome. According to the analysis, the time from onset to puncture within 12 h (odds ratio: 4.34; 95% confidence interval: 1.55-12.16; P = 0.01), presence of collateral flow via PCoA (odds ratio: 0.31; 95%CI: 0.12-0.79; P = 0.01) or between PICA and SCA (odds ratio: 0.18; 95%CI: 0.07-0.47; P = 0.00), equal or less than 15 points on baseline NIHSS (area under the curve 0.79, 95% CI 0.69-0.89; sensitivity = 69.1%, specificity = 81.8%; P = 0.00), and equal or less than 1.5 points on diffusion weighted imaging Renard score (area under the curve 0.63, 95% CI 0.51-0.75; sensitivity = 83.6%, specificity = 39.4%; P = 0.046) were independently associated with favorable outcome.

CONCLUSIONS

Renard diffusion weighted imaging score may be an independent predictor of functional outcome in basilar artery occlusion patients after endovascular treatment.

Acute Stroke Treatment in Patients with Basilar Artery Occlusion: A Single-Center Observational Study

Background

Acute ischemic stroke (AIS) due to basilar artery occlusion (BAO) represents 1–4′ of all ischemic strokes. BAO results in strokes associated with a high risk of a poor functional outcome and, in 86–95′ of the untreated cases, it results in death because of the vital cerebral structures involved. Diagnosis can be delayed because of the variability in presenting symptoms, and acute treatment is often attempted even beyond 6 h from symptoms onset because of the high risk of a fatal prognosis.

Objective

In this observational study, we retrospectively analyzed patients with AIS due to BAO referred to the stroke center of the University Hospital of Messina. We aimed to assess prognostic factors and to evaluate the association between clinical outcome and posterior circulation Alberta Stroke Program Early CT Score (pc-ASPECTS) and collateral status.

Method

BAO was confirmed by cerebral computed tomography (CT) angiography or cerebral angiography. All patients underwent CT scan and magnetic resonance imaging (MRI). We assessed the pc-ASPECTS on diffusion-weighted imaging (DWI) MR images and the Posterior Circulation Collateral Score (PC-CS) for every patient. Functional outcome was assessed at 3 months using the modified Rankin Scale (mRS).

Results

The study population consisted of 27 patients; 16 males and 11 females. The mean age was 66 (±14) years. We observed a favorable outcome (mRS 0–3) in 40.7′ of cases, 25.9′ reached mRS 0–2, and 29.6′ had a poor clinical outcome (mRS 4–5). Patient survival was 70.4′, whereas 8 patients died (29.6′). In 7 patients, pc-ASPECTS was ≥7. According to the PC-CS, 33.3′ had moderate collaterals and 63.0′ had good collateral status prior to receiving the treatment. Favorable outcome was significantly associated with age, NIHSS score at admission, pc-ASPECTS, hypercholesterolemia, and female sex but not with the other risk factors.

Conclusions

In our study, we found that younger age, low NIHSS score at admission, and high pc-ASPECTS, but not onset to treatment time, are associated with a favorable clinical outcome. Transferred patients did not have a significantly poorer outcome. These findings confirm that acute stroke treatment improves clinical outcome in BAO patients, in spite of a delayed diagnosis and an extended therapeutic window, considering lesion volume and localization in DWI MRI.