Simultaneous Luminal and Hemodynamic Evaluation of the Cervical Arteries Using Nonenhanced 3D Quantitative Quiescent-Interval Slice-Selective Magnetic Resonance Angiography

Background: Luminal and hemodynamic evaluations of the cervical arteries inform the diagnosis and management of patients with cervical arterial disease.

Purpose: To demonstrate a 3D nonenhanced quantitative quiescent interval slice-selective (qQISS) magnetic resonance angiographic (MRA) strategy that provides simultaneous hemodynamic and luminal evaluation of the cervical arteries.

Study type: Prospective.

Subjects: Six healthy volunteers (3 female, 3 male, age = 35.7 ± 10.3 years) and 14 patients with cerebrovascular disease (12 female, 2 male, age = 56.6 ± 14.0 years).

Field strength/sequences: 3 T, ungated 3D tilted-slab qQISS, pulse-gated 2D phase contrast (PC), ungated 3D PC, and 3D time-of-flight (TOF) gradient-echo protocols.

Assessment: Four readers scored 29 arterial segments on 3D qQISS volumes for image quality using a 4-point scale (1: non-diagnostic, 2: fair, 3: good, 4: excellent). Time-averaged arterial flow velocities and volume flow rates obtained with qQISS and PC protocols were compared. Arterial lumen area and radius measures obtained with 3D protocols were compared in a subgroup.

Statistical tests: Gwet's AC2; intraclass correlation coefficient (ICC); Pearson's correlation; Bland-Altman. P values <0.05 were considered statistically significant.

Results: 3D qQISS provided good-to-excellent image quality for depicting the cervical arteries (mean scores of 3.72 ± 0.55, 3.55 ± 0.66, 3.42 ± 0.72, and 3.66 ± 0.73 for readers 1, 2, 3, and 4) with significant inter-reader agreement (AC2 = 0.91, ICC = 0.53) in image scoring, significantly agreed with pulse-gated 2D PC for time-averaged total flow velocity (ICC = 0.83) and volume flow rate (ICC = 0.92), and significantly agreed with 3D PC for total flow velocity (ICC = 0.70), volume flow rate (ICC = 0.91), and component flow velocity (ICC = 0.89). Compared with 3D PC, 3D qQISS better agreed with 3D TOF for arterial lumen area (ICC = 0.97 vs. 0.72) and radius (ICC = 0.94 vs. 0.74).

Data conclusion: Nonenhanced 3D qQISS provides high-quality sub-1 mm³ spatial resolution imaging of the cervical arteries, excellent agreement of arterial structural measures with respect to 3D TOF, and time-averaged hemodynamic data without the need for additional PC imaging.

Plain language summary: Magnetic resonance angiography (MRA), a method for depicting blood vessels within the body, can be used to evaluate arterial diseases and disorders of the neck. MRA methods routinely used to evaluate the neck arteries do not measure blood flow speed and volume, while other methods for obtaining this information provide less accurate pictures of arterial structure and are not routinely collected. This article reports a new method for MRA that clearly and efficiently portrays the neck arteries without using injected dyes, and provides measurements of arterial blood flow speed and volume.

Evidence level: 2 TECHNICAL EFFICACY: Stage 1.