# Diagnostic accuracy of transcranial Doppler for cerebral vasospasm in aneurysmal subarachnoid hemorrhage: a systematic review and meta-analysis

## TL;DR

This study evaluates how well transcranial Doppler ultrasound can detect brain blood vessel spasms in patients with a type of brain bleed.

## Contribution

The study provides a systematic review and meta-analysis of TCD's diagnostic accuracy for cerebral vasospasm in aneurysmal subarachnoid hemorrhage.

## Key findings

- TCD has a pooled sensitivity of 76% and specificity of 77% for detecting cerebral vasospasm.
- The area under the ROC curve was 0.82, indicating good diagnostic accuracy.
- Subgroup analyses showed higher accuracy when using the Lindegaard ratio.

## Abstract

With the increasing adoption of point-of-care ultrasound in neurocritical care, transcranial Doppler (TCD) has gained renewed attention as a bedside monitoring tool for detecting cerebral vasospasm and delayed cerebral ischemia (DCI) in patients with aneurysmal subarachnoid hemorrhage (aSAH). Among cerebral vessels, the middle cerebral artery (MCA) is the most frequently evaluated using point-of-care ultrasound. This study aimed to determine the diagnostic accuracy of TCD for detecting cerebral vasospasm that may lead to DCI in the MCA of patients with aSAH.

We conducted a systematic literature search of MEDLINE, the Cochrane Central Register of Controlled Trials, Embase, ClinicalTrial.gov, and the WHO International Clinical Trials Registry Platform through December 16, 2025, and manually searched the reference lists of relevant articles. We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and assessed study quality using the Quality Assessment of Diagnostic Accuracy Studies-2 tool. A meta-analysis was conducted to pool the diagnostic accuracy of TCD for detecting cerebral vasospasm in aSAH. The study protocol was prospectively registered in PROSPERO (CRD42024542692).

Among the 3100 studies identified, 80 underwent full-text review, and 32 studies including 3594 patients were included in the meta-analysis. Pooled sensitivity and specificity were 76% (95% confidence interval [CI]: 70–81%) and 77% (95% CI, 68–84%), respectively, for cerebral vasospasm. The area under the receiver operating characteristic curve was 0.82. The positive likelihood ratio was 3.4 (95% CI, 2.8–4.7), and the negative likelihood ratio was 0.3 (95% CI, 0.24–0.40). Subgroup analyses showed sensitivity and specificity of 76% (95% CI, 69–81%) and 75% (95% CI, 66–83%) using blood-flow velocity in the MCA (28 studies; n = 3161), 82% (95% CI, 58–94%) and 88% (95% CI, 64–97%) using the Lindegaard ratio (7 studies; n = 1162), and 79% (95% CI, 72–85%) and 82% (95% CI, 66–91%) in studies with low risk of bias (9 studies; n = 1223).

TCD demonstrates promising diagnostic accuracy for detecting cerebral vasospasm that may lead to DCI. Incorporating TCD into multimodal neuromonitoring may improve the clinical management of aSAH.

The online version contains supplementary material available at 10.1186/s13054-026-05849-6.