# Admission hyperdense sinus sign predicts poorer outcomes in cerebral venous sinus thrombosis

## TL;DR

A visible sign on CT scans called the hyperdense sinus sign predicts worse outcomes for patients with cerebral venous sinus thrombosis.

## Contribution

The study shows that the hyperdense sinus sign is a reliable early predictor of poor outcomes in cerebral venous sinus thrombosis.

## Key findings

- HDSS was associated with lower excellent functional outcomes and higher remote seizures at 90 days.
- HDSS patients had more extensive thrombosis and parenchymal injuries like intracerebral hemorrhage.
- HDSS independently predicted reduced odds of excellent functional recovery and increased seizures.

## Abstract

The hyperdense sinus sign (HDSS) is a readily identifiable non-contrast CT marker of acute thrombus in cerebral venous sinus thrombosis (CVST). We aimed to characterize HDSS associated features and prognostic significance.

Data from prospective multicenter CVST registries was analysed. HDSS was defined as attenuation > 70 Hounsfield units within a thrombosed venous structure. Baseline characteristics and outcomes were compared between patients with and without HDSS on admission CT. Multivariable logistic regression identified independent predictors of Excellent-Functional-Outcome (mRS 0–1) and remote seizures.

Among 465 patients (mean age 41.9 ± 18.4 years; 64.3% female), 178 (38.3%) exhibited HDSS. Patients with HDSS had higher rates of oral contraceptives use (28% vs 18%, p = 0.009), seizures at presentation (23% vs 14%, p = 0.015), superior sagittal (45% vs 35%, p = 0.028) and transverse sinus involvement (78% vs 67%, p = 0.01), deep venous thrombosis (8% vs 2%, p = 0.003), cortical vein thrombosis (19% vs 9%, p = 0.004), and multisite occlusion (34% vs 22%, p = 0.002). Parenchymal lesions were more common in HDSS patients, including intracerebral hemorrhage (27% vs 13%, p < 0.001) and venous infarction (22% vs 11%, p = 0.004). On day-90, HDSS was associated with lower Excellent-Functional-Outcome rates (71% vs 82%, p = 0.022), higher rates of remote seizures (9% vs 3%, p = 0.001), and similar recanalization rates. HDSS independently predicted reduced odds of Excellent-Functional-Outcome (OR = 0.491 [0.261–0.926], p = 0.028) and increased remote seizures (OR = 2.693 [1.057–6.861], p = 0.038).

HDSS identifies a CVST subgroup with more extensive thrombosis, greater parenchymal injury, and poorer outcomes, supporting its utility in early risk stratification.

The online version contains supplementary material available at 10.1007/s00415-026-13660-0.