Accelerated whole brain intracranial vessel wall imaging using black blood fast spin echo with compressed sensing (CS-SPACE).
OBJECTIVE
Develop and optimize an accelerated, high-resolution (0.5 mm isotropic) 3D black blood MRI technique to reduce scan time for whole-brain intracranial vessel wall imaging.


MATERIALS AND METHODS
A 3D accelerated T1-weighted fast-spin-echo prototype sequence using compressed sensing (CS-SPACE) was developed at 3T. Both the acquisition [echo train length (ETL), under-sampling factor] and reconstruction parameters (regularization parameter, number of iterations) were first optimized in 5 healthy volunteers. Ten patients with a variety of intracranial vascular disease presentations (aneurysm, atherosclerosis, dissection, vasculitis) were imaged with SPACE and optimized CS-SPACE, pre and post Gd contrast. Lumen/wall area, wall-to-lumen contrast ratio (CR), enhancement ratio (ER), sharpness, and qualitative scores (1-4) by two radiologists were recorded.


RESULTS
The optimized CS-SPACE protocol has ETL 60, 20% k-space under-sampling, 0.002 regularization factor with 20 iterations. In patient studies, CS-SPACE and conventional SPACE had comparable image scores both pre- (3.35 ± 0.85 vs. 3.54 ± 0.65, p = 0.13) and post-contrast (3.72 ± 0.58 vs. 3.53 ± 0.57, p = 0.15), but the CS-SPACE acquisition was 37% faster (6:48 vs. 10:50). CS-SPACE agreed with SPACE for lumen/wall area, ER measurements and sharpness, but marginally reduced the CR.


CONCLUSION
In the evaluation of intracranial vascular disease, CS-SPACE provides a substantial reduction in scan time compared to conventional T1-weighted SPACE while maintaining good image quality.
['Zhu|Chengcheng|C|http://orcid.org/0000-0001-6898-549X', 'Tian|Bing|B|', 'Chen|Luguang|L|', 'Eisenmenger|Laura|L|', 'Raithel|Esther|E|', 'Forman|Christoph|C|', 'Ahn|Sinyeob|S|', 'Laub|Gerhard|G|', 'Liu|Qi|Q|', 'Lu|Jianping|J|', 'Liu|Jing|J|', 'Hess|Christopher|C|', 'Saloner|David|D|']
D000328:Adult D000368:Aged D000465:Algorithms D000783:Aneurysm D050197:Atherosclerosis D001921:Brain D002560:Cerebrovascular Circulation D002561:Cerebrovascular Disorders D003287:Contrast Media D005260:Female D064368:Healthy Volunteers D006801:Humans D007091:Image Processing, Computer-Assisted D021621:Imaging, Three-Dimensional D008279:Magnetic Resonance Imaging D008297:Male D008875:Middle Aged D015233:Models, Statistical D016012:Poisson Distribution D015203:Reproducibility of Results D059629:Signal-To-Noise Ratio
Compressed sensing Aneurysm Atherosclerosis 3D black blood SPACE Intracranial vessel wall MRI