High resolution MRI of the deep brain vascular anatomy at 8 Tesla: susceptibility-based enhancement of the venous structures.
OBJECTIVE
The purpose of this work was to describe the deep vascular anatomy of the human brain using high resolution MR gradient echo imaging at 8 T.


METHODS
Gradient echo images were acquired from the human head using a transverse electromagnetic resonator operating in quadrature and tuned to 340 MHz. Typical acquisition parameters were as follows: matrix = 1,024 x 1,024, flip angle = 45 degrees, TR = 750 ms, TE = 17 ms, FOV = 20 cm, slice thickness = 2 mm. This resulted in an in-plane resolution of approximately 200 microm. Images were analyzed, and vascular structures were identified on the basis of location and course.


RESULTS
High resolution ultra high field magnetic resonance imaging (UHFMRI) enabled the visualization of many small vessels deep within the brain. These vessels were typically detected as signal voids, and the majority represented veins. The prevalence of the venous vasculature was attributed largely to the magnetic susceptibility of deoxyhemoglobin. It was possible to identify venous structures expected to measure below 100 microm in size. Perforating venous drainage within the deep gray structures was identified along with their parent vessels. The course of arterial perforators was more difficult to follow and not as readily identified as their venous counterparts.


CONCLUSIONS
The application of high resolution gradient echo methods in UHFMRI provides a unique detailed view of particularly the deep venous vasculature of the human brain.
Christoforidis
G A
GA
Center for Advanced Biomedical Imaging, Department of Radiology, Ohio State University, Columbus 43210, USA.
Bourekas
E C
EC
Baujan
M
M
Abduljalil
A M
AM
Kangarlu
A
A
Spigos
D G
DG
Chakeres
D W
DW
Robitaille
P M
PM
D001158:Arteries / Q000033:anatomy & histology; D016477:Artifacts; D001921:Brain / Q000098:blood supply*; D002421:Caudate Nucleus / Q000098:blood supply; D002550:Cerebral Veins / Q000033:anatomy & histology*; D002552:Cerebral Ventricles / Q000098:blood supply; D002831:Choroid Plexus / Q000098:blood supply; D003337:Corpus Callosum / Q000098:blood supply; D003342:Corpus Striatum / Q000098:blood supply; D055590:Electromagnetic Phenomena / Q000295:instrumentation; D004578:Electron Spin Resonance Spectroscopy; D006454:Hemoglobins; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D015995:Prevalence; D013788:Thalamus / Q000098:blood supply
D006454:Hemoglobins; C100003:deoxyhemoglobin