Patients
This retrospective study was approved by the Institutional Review Board of our hospital. The requirement to obtain informed consent was waived due to its retrospective nature.
We retrospectively reviewed the PACS of our institution for subjects who received simultaneous head and neck MRA and carotid duplex sonography from January 2017 to June 2018 as part of a routine health examination. A total of 223 healthy subjects without any history or symptoms of cerebrovascular disease were identified.
Based on the imaging studies, 3 subjects were excluded due to segmental narrowing (> 50%) of the common/internal carotid arteries, 4 due to proximal anterior cerebral artery (ACA)/ middle cerebral artery stenosis, 1 due to a persistent trigeminal artery, 2 due to vascular anomalies such as cerebral aneurysm, 2 due to arteriovenous malformation/fistula, and 1 due to a moyamoya syndrome. These 13 excluded subjects were used for the interobserver reliability test. Thus, 210 subjects (133 males, 77 females; mean age 54 ± 9 years; range, 31 to 76 years) were included in the analysis.