Posterior circulation collaterals as predictors of outcome in basilar artery occlusion: a sub-analysis of the BASICS
Fabricio O Lima1, Felipe A Rocha2, Henrique C Silva2
1Neurology Service, Hospital Geral de Fortaleza, Fortaleza, Brazil.
Insights
Posterior circulation collateral grading systems, BATMAN and PC-CS, showed modest prognostic accuracy for basilar artery occlusion outcomes. Only the PC-CS score independently predicted favorable outcomes at three months.
Area of Science:
- Neurology
- Vascular Neurology
- Neuroimaging
Background:
- Basilar artery occlusion (BAO) is a severe neurological condition with high morbidity and mortality.
- Effective outcome prediction is crucial for managing BAO patients.
Purpose of the Study:
- To evaluate posterior circulation collateral grading systems (BATMAN score and PC-CS) as outcome predictors in BAO.
- To compare the prognostic value of the BATMAN score and PC-CS in the BASICS trial.
Main Methods:
- Sub-analysis of the BASICS trial data.
- Analysis of baseline clinical and CT/CTA imaging variables.
- Multivariable logistic regression and ROC curve analysis to assess prognostic value.
Main Results:
- Both BATMAN and PC-CS collateral scores were associated with favorable 3-month outcomes, but with modest accuracy.
- The PC-CS score demonstrated better prognostic accuracy (AUC 0.67) compared to BATMAN (AUC 0.62).
- Age, NIHSS score, and PC-CS collateral score were independently associated with favorable outcomes.
Conclusions:
- Posterior circulation collateral grading systems offer modest prognostic value in BAO.
- The PC-CS collateral grading system independently predicted favorable outcomes at 3 months in BAO patients.
Introduction And Purpose:
Basilar artery occlusion (BAO) is still one of the most devastating neurological conditions associated with high morbidity and mortality. In the present study, we aimed to assess the role of posterior circulation collaterals as predictors of outcome in the BASICS trial and to compare two grading systems (BATMAN score and PC-CS) in terms of prognostic value.
Methods:
We performed a sub-analysis of the BASICS trial. Baseline clinical and imaging variables were analyzed. For the imaging analysis, baseline CT and CTA were analyzed by a central core lab. Only those patients with good or moderate quality of baseline CTA and with confirmed BAO were included. Multivariable binary logistic regression analysis was used to test the independent association of clinical and imaging characteristics with a favorable outcome at 3 months (defined as a modified Rankin Score of ≤3). ROC curve analysis was used to assess and compare accuracy between the two collateral grading systems.
Results:
The mean age was 67.0 (±12.5) years, 196 (65.3%) patients were males and the median NIHSS was 21.5 (IQR 11-35). Median NCCT pc-ASPECTS was 10 (IQR10-10) and median collateral scores for BATMAN and PC-CS were 8 (IQR 7-9) and 7 (IQR 6-8) respectively. Collateral scores were associated with favorable outcome at 3 months for both BATMAN and PC-CS but only with a modest accuracy on ROC curve analysis (AUC 0.62, 95% CI [0.55-0.69] and 0.67, 95% CI [0.60-0.74] respectively). Age (OR 0.97, 95% CI [0.95-1.00]), NIHSS (OR 0.91, 95% CI [0.89-0.94]) and collateral score (PC-CS - OR 1.2495% CI [1.02-1.51]) were independently associated with clinical outcome.
Conclusion:
The two collateral grading systems presented modest prognostic accuracy. Only the PC-CS was independently associated with a favorable outcome at 3 months.
