Impact of high field (3.0 T) magnetic resonance imaging on diagnosis of osteochondral defects in the ankle joint.
OBJECTIVE
To evaluate high field magnetic resonance (MR) imaging for imaging of osteochondral defects.


METHODS
Nine osteochondral defects were simulated in three cadaveric talus specimens using a diamond drill. All specimens were examined on a 1.0 T MR unit and a 3.0 T MR unit. A T2-weighted turbo spin-echo (TSE) sequence with a 2 mm slice thickness and a 256 x 256 matrix size was used on both scanners. The visibility of the osteochondral separation and the presence of susceptibility artifacts at the drilling bores were scored on all images.


RESULTS
Compared to the 1.0 T MR unit, the protocol on the 3.0 T MR unit allowed a better delineation of the disruption of the articular cartilage and a better demarcation of the subchondral defect. Differences regarding the visualization of the subchondral defect were found to be statistically significant (P<0.05). Differences with regard to susceptibility artifacts at the drilling bores were not statistically significant (P>0.05). The average SNR was higher using 3.0 T MRI (SNR=12), compared to 1.0 T MRI (SNR=7).


CONCLUSIONS
High field MRI enables the acquisition of images with sufficient resolution and higher SNR and has therefore the potential to improve the staging of osteochondral defects.
Schibany
N
N
Department of Radiology/Osteology, University of Vienna, Medical School, Währinger Gürtel 18-20, 1090 Vienna, Austria. nadja.schibany@meduniwien.ac.at
Ba-Ssalamah
A
A
Marlovits
S
S
Mlynarik
V
V
Nöbauer-Huhmann
I M
IM
Striessnig
G
G
Shodjai-Baghini
M
M
Heinze
G
G
Trattnig
S
S
D000843:Ankle Joint; D016477:Artifacts; D002102:Cadaver; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D010007:Osteochondritis / Q000473:pathology*