# Net water uptake and ASPECTS in predicting futile recanalization for acute large vessel occlusion stroke: insights from time window stratification

## TL;DR

This study shows that combining net water uptake and ASPECTS scores can help predict poor outcomes in stroke patients after treatment, especially when the treatment is delayed.

## Contribution

A novel nomogram integrating ASPECTS and net water uptake is developed for predicting futile recanalization in late-time-window stroke patients.

## Key findings

- Baseline NWU and ASPECTS were independent predictors of futile recanalization in late time windows.
- A nomogram integrating NWU and ASPECTS achieved strong predictive accuracy (AUC of 0.880).
- Patients with FR had higher NWU, lower ASPECTS, and worse clinical outcomes.

## Abstract

This study aimed to evaluate the prognostic value of Alberta Stroke Program Early CT Score (ASPECTS)-based net water uptake (NWU) in predicting futile recanalization (FR) and develop a nomogram integrating NWU and clinical parameters for personalized risk stratification in early or late time windows in acute ischemic stroke (AIS) at admission.

This retrospective study investigated AIS patients with large vessel occlusion who achieved successful recanalization from January 2022 to November 2024. Baseline ASPECTS-NWU was automatically quantified from the admission CT. The primary outcome was FR, defined as a modified Rankin Scale (mRS) score of 3–6 at 90 days following successful recanalization (modified Thrombolysis in Cerebral Infarction score, 2b/3). Intergroup comparisons of clinical and neuroimaging parameters were performed using the Mann–Whitney U test for continuous variables and the χ2 test for categorical measures. Bivariate correlations between NWU values and other covariates were assessed using Spearman’s rho coefficients. Multivariable logistic regression identified independent predictors of FR, and a subsequent nomogram was constructed. The logistic regression model was tested using the 5-fold cross-validation. The predictive accuracy of different models was evaluated using the receiver operating characteristic curve and DeLong’s test.

A total of 168 patients were included, and FR occurred in 95 patients. Patients with FR were older, had higher National Institutes of Health Stroke Scale scores, an increased number of passes, lower ASPECTS, elevated NWU, larger cerebral blood flow (CBF) < 30% volume, and increased hypoperfusion intensity ratio (HIR), regardless of the time window. In the late time window, multivariable analysis identified baseline NWU and ASPECTS as independent predictors of FR. A nomogram integrating these two factors demonstrated strong predictive power, with an area under the curve of 0.880.

Baseline NWU and ASPECTS were independent predictors of AIS patients with FR in the late time window. The developed nomogram integrating NWU with ASPECTS provides a clinically actionable tool for pre-endovascular therapy risk stratification.