High-resolution contrast-enhanced vessel wall imaging in patients with suspected cerebral vasculitis: Prospective comparison of whole-brain 3D T1 SPACE versus 2D T1 black blood MRI at 3 Tesla

Abstract

Purpose: Vessel wall imaging (VWI) using T1 dark blood MRI can depict inflammation of intracranial arteries in patients with cerebral vasculitis. Recently, 3D VWI sequences were introduced at 3 Tesla. We aimed to compare 2D and 3D VWI for detection of intracranial vessel wall enhancement (VWE) in patients suspected of cerebral vasculitis.

Methods: 44 MRI scans of 39 patients were assessed that included bi-planar 2D T1 and whole-brain 3D T1 SPACE dark blood VWI pre and post contrast. Visibility and VWE were analyzed in 31 pre-specified intracranial artery segments. Additionally, leptomeningeal and parenchymal contrast enhancement was assessed.

Results: Overall, more arterial segments were visualized with 3D VWI (p<0.0001). Detection of VWE showed fair agreement between 2D and 3D VWI (κ = 0.583). On segmental level, more VWE was detected in intradural ICA by 2D VWI (p<0.001) and in VA V4 segment by 3D VWI (p<0.05). 3D VWI showed more leptomeningeal (p<0.05) and parenchymal (p<0.01) contrast enhancement. In patients with positive diagnosis of cerebral vasculitis, sensitivity was of 67% (2D and 3D VWI) and specificity was 44% (2D VWI) and 48% (3D VWI); more VWE was seen in arteries distal to VA and ICA compared to non-vasculitic patients.

Conclusion: 2D and 3D VWI differed in the ability to detect VWE. Whole brain coverage with better evaluability of VAs and distal intracranial artery segments, and depiction of more parenchymal and leptomeningeal enhancement make 3D VWI more favorable. As VWE in arteries distal to VA and ICA may be used for discrimination of vasculitic and non-vasculitic patients, future increase in spatial resolution of 3D VWI sequences may be beneficial.

Fig 1. 51-year-old female patient with neuroborreliosis, bilateral neuritis of 3rd nerve, and right MCA territory lenticulostriate infarct.

TOF MRA (targeted MIP, A) shows bilateral medium-grade long-segmental stenosis of intradural ICAs and left MCA M1 segment, and high-grade right MCA stenosis. 2D and 3D VWI in coronal and axial views: Thin concentric VWE (white arrows) of right supraclinoid ICA is barely visible on 3D (B, D) and clearly visible on 2D (C, E) VWI. Concentric VWE at left MCA bifurcation/proximal M2 (white arrowheads) is well visualized on both 2D (E) and 3D VWI (D).

Fig 2. 68-year female patient with giant cell arteriitis and left MCA territory infarcts.

CE-MRA of supraaortic arteries (A) shows bilateral long segmental irregular VA stenosis involving right V3 and V4 as well as left V4 segments (white arrowheads) and long-segmental stenosis of left extra- and intracranial ICA (white arrows). 3D VWI with multiplanar views (B-D) depicts multiple areas of long-segmental concentric VWE in bilateral V3 and V4 segments and left cervical/petrosal ICA (white arrows). Due to limited coverage, 2D VWI shows only parts of the enhancing lesions in left petrosal ICA segment (black arrow in E).

Fig 3

39-year-old male patient with possible migraine and high-grade MCA stenosis: 2D axial (A) and coronal (B) VWI reveals short segmental distal MCA VWE (arrows) that resembles a concentric appearance. 3D VWI with axial (C) and sagittal oblique (D) reformatted images: The latter image which is orientated perpendicular to MCA vessel course shows that there is obvious eccentric VWE (arrow) which is not obvious on standard 2D views.