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.
Department of Clinical Radiology, University of Munich, Grosshadern Campus, Munich, Germany. Tobias.Saam@med.uni-muenchen.de
Tobias
T
Saam
Jose G
JG
Raya
Clemens C
CC
Cyran
Katja
K
Bochmann
Georgios
G
Meimarakis
Olaf
O
Dietrich
Dirk A
DA
Clevert
Ute
U
Frey
Chun
C
Yuan
Thomas S
TS
Hatsukami
Abe
A
Werf
Maximilian F
MF
Reiser
Konstantin
K
Nikolaou
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