High resolution carotid black-blood 3T MR with parallel imaging and dedicated 4-channel surface coils.
BACKGROUND
Most of the carotid plaque MR studies have been performed using black-blood protocols at 1.5 T without parallel imaging techniques. The purpose of this study was to evaluate a multi-sequence, black-blood MR protocol using parallel imaging and a dedicated 4-channel surface coil for vessel wall imaging of the carotid arteries at 3 T.


METHODS
14 healthy volunteers and 14 patients with intimal thickening as proven by duplex ultrasound had their carotid arteries imaged at 3 T using a multi-sequence protocol (time-of-flight MR angiography, pre-contrast T1w-, PDw- and T2w sequences in the volunteers, additional post-contrast T1w- and dynamic contrast enhanced sequences in patients). To assess intrascan reproducibility, 10 volunteers were scanned twice within 2 weeks.


RESULTS
Intrascan reproducibility for quantitative measurements of lumen, wall and outer wall areas was excellent with intraclass correlation coefficients >0.98 and measurement errors of 1.5%, 4.5% and 1.9%, respectively. Patients had larger wall areas than volunteers in both common carotid and internal carotid arteries and smaller lumen areas in internal carotid arteries (p < 0.001). Positive correlations were found between wall area and cardiovascular risk factors such as age, hypertension, coronary heart disease and hypercholesterolemia (Spearman's r = 0.45-0.76, p < 0.05). No significant correlations were found between wall area and body mass index, gender, diabetes or a family history of cardiovascular disease.


CONCLUSIONS
The findings of this study indicate that high resolution carotid black-blood 3 T MR with parallel imaging is a fast, reproducible and robust method to assess carotid atherosclerotic plaque in vivo and this method is ready to be used in clinical practice.
Saam
Tobias
T
Department of Clinical Radiology, University of Munich, Grosshadern Campus, Munich, Germany. Tobias.Saam@med.uni-muenchen.de
Raya
Jose G
JG
Cyran
Clemens C
CC
Bochmann
Katja
K
Meimarakis
Georgios
G
Dietrich
Olaf
O
Clevert
Dirk A
DA
Frey
Ute
U
Yuan
Chun
C
Hatsukami
Thomas S
TS
Werf
Abe
A
Reiser
Maximilian F
MF
Nikolaou
Konstantin
K
D000328:Adult; D000368:Aged; D002340:Carotid Artery Diseases / Q000175:diagnosis*; D017536:Carotid Artery, Common / Q000473:pathology*; D002343:Carotid Artery, Internal / Q000473:pathology*; D016022:Case-Control Studies; D004867:Equipment Design; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D018810:Magnetic Resonance Angiography / Q000295:instrumentation*; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D018616:Ultrasonography, Doppler, Duplex; D055815:Young Adult