Angiography versus angio-based fractional flow in assessing intracranial vertebrobasilar artery stenosis.

OBJECTIVES

To evaluate the diagnostic performance of Angio-based fractional flow (Angio-FF) compared to the degree of stenosis (DS) in identifying symptomatic intracranial vertebrobasilar artery stenosis (IVBS) and assess its utility across lesion subgroups.

MATERIALS AND

METHODS

A retrospective analysis of patients with IVBS was conducted at our institution. Inclusion criteria included patients aged > 18 years with unilateral IVBS (40-90%) confirmed by digital subtraction angiography. Angio-FF was calculated using specialized software. Diagnostic accuracy, sensitivity, specificity, positive/negative predictive values (PPV/NPV), and the area under the curve (AUC) were compared between Angio-FF and DS.

RESULTS

In 120 patients, 84 were symptomatic, and 36 were asymptomatic. The median Angio-FF value was significantly lower in symptomatic lesions (0.66 vs. 0.88, p < 0.001). Angio-FF showed superior diagnostic performance over DS in identifying symptomatic IVBS (AUC: 0.847 vs. 0.640; p < 0.001). The optimal Angio-FF cutoff value for distinguishing symptomatic IVBS was 0.74, with sensitivity, specificity, and accuracy of 71.4%, 86.1%, and 75.8%, respectively. Additionally, Angio-FF showed relatively good diagnostic performance across various lesion subgroups, including different lesion lengths, location, and DS.

CONCLUSIONS

Angio-FF outperformed DS in identifying symptomatic IVBS. It may serve as a reliable tool for identifying symptomatic IVBS in diverse patient populations.

KEY POINTS: Question Does Angio-based fractional flow (Angio-FF) provide superior diagnostic accuracy compared to the degree of stenosis alone in identifying symptomatic intracranial vertebrobasilar artery stenosis (IVBS)? Findings Angio-FF demonstrated superior diagnostic accuracy, with an optimal cutoff value of 0.74 and consistent performance across various lesion subgroups. Clinical relevance Angio-FF improves hemodynamic risk stratification in IVBS and may facilitate more individualized treatment strategies.