Quantitative measures of early cerebral edema on computed tomography may help determine which patients with large ischemic strokes benefit from endovascular thrombectomy, according to findings from the multicenter TENSION trial.

Lead study author Gabriel Broocks, MD, of the Department of Diagnostic and Interventional Neuroradiology at the University Medical Center Hamburg-Eppendorf, and colleagues reported that patients with lower net water uptake (NWU) on admission computed tomography (CT) had better functional outcomes following endovascular thrombectomy (EVT) compared with those who received best medical treatment (BMT) alone, whereas patients with higher NWU showed no additional benefit.

The analysis included 207 adult patients with anterior circulation stroke and large infarct cores, defined by Alberta Stroke Program Early CT Scores (ASPECTS) of 3 to 5. Researchers randomly assigned the patients to receive BMT alone or in combination with EVT across 41 centers in Europe and Canada between 2018 and 2023. The median age of the patients was 74 years, and 51% of them identified as female. The median NWU was 16.4%, with a 15% threshold emerging as a key marker; patients below this level benefited from EVT, whereas those at or above 15% derived little to no advantage.

At 90 days, the median modified Rankin Scale (mRS) score was 5, and 20% of the patients achieved functional independence. Those with lower NWU were randomized earlier (median = 4.1 hours vs 5 hours) and had lower 24-hour National Institutes of Health Stroke Scale scores (16 vs 19). EVT achieved complete reperfusion of the middle cerebral artery territory in 64% of the treated patients. The incidence of intracerebral hemorrhage was 46% overall and didn't significantly differ between treatment groups. The researchers noted that NWU, measurable on standard noncontrast CT, could serve as a practical imaging biomarker to identify viable tissue and refine EVT selection in large-core stroke.

The researchers acknowledged several limitations, including the exploratory nature of the analysis and an absence of randomized validation for densitometric edema assessment. The NWU threshold was derived of post hoc and requires confirmation in external cohorts. In addition, variability in region-of-interest definition may affect measurements, although prior studies have shown good consistency across modalities.

The study was supported by the EU Horizon 2020 Research and Innovation Programme. Several authors reported institutional grants and consulting fees from medical device and pharmaceutical companies.

Source: Radiology