Diagnostic yield of TOF-MRA for detecting incidental vascular lesions in patients with cognitive impairment: observational cohort study

Abstract

We investigated the diagnostic yield of three-dimensional (3D) TOF-MRA for detecting incidental extra- or intracranial artery stenosis and intracranial aneurysm in patients with cognitive impairment. This retrospective study included 1753 patients (mean age, 70.2 ± 10.6 years; 1044 women) with cognitive impairment undergoing our brain MRI protocol from January 2013 to February 2020. In total, 199 intracranial aneurysms were detected among 162 patients (9.2%, 162/1753). 3D TOF-MRA revealed significant artery stenoses (> 50% stenosis) in 162 patients (9.2%, 162/1753). The overall diagnostic yield of TOF-MRA was 16.8% (294/1753). Fifteen patients (aneurysm: 11 patients, stenosis: 4 patients) (5.1%, 15/294) were further treated with endovascular intervention or surgery. Thus, the "number needed to scan" was 116 for identifying one patient requiring vascular intervention. Multivariate logistic regression analysis showed that being female (odds ratio [OR] 2.05) and old age (OR 1.04) were independent risk factors for intracranial aneurysm; being male (OR 1.52), old age (OR 1.06), hypertension (OR 1.78), and ischemic heart disease history (OR 2.65) were independent risk factors for significant artery stenosis. Despite the high diagnostic yield of 16.8% for detecting vascular lesions, the additional benefit of the 3D TOF-MRA was questionable given that only a minority of the patients needed further treatment.