Combined T1-T2 mapping of human femoro-tibial cartilage with turbo-mixed imaging at 1.5T.
OBJECTIVE
To evaluate the influence of Gd-DTPA on cartilage T2 mapping using turbo-mixed (tMIX) imaging, and to show the possible usefulness of the tMIX technique for simultaneously acquiring T1 and T2 information in cartilage.


METHODS
Twenty volunteers underwent MRI of the knee using the tMIX sequence before and after gadolinium administration. T1 and T2 maps were calculated. The mean T1 was determined on the pre- and postcontrast T1 maps. T2 relaxation values before and after gadolinium administration were statistically analyzed.


RESULTS
The obtained relaxation values are in correspondence with previously published data. The mean T1 before gadolinium administration was 449 msec +/- 34.2 msec (SD), and after gadolinium administration it was 357 msec +/- 55.8 msec (SD). The postcontrast T1 relaxation range was 221.5-572.8 msec. The mean T2 of the precontrast T2 maps was 34.2 msec +/- 3.1 msec (SD), and the mean T2 of the postcontrast T2 maps was 32.5 msec +/- 3.1 msec (SD). These are statistically significant different values. A correction for the postcontrast T2 values, using a back-calculation algorithm, yielded a 98% correlation with the precontrast T2 values.


CONCLUSIONS
The absolute difference of pre- and postcontrast T2 is very small and is ruled out using the back-calculation algorithm. Combined T1-T2 tMIX cartilage mapping is a valuable alternative for separate T1 and T2 cartilage mapping.
Van Breuseghem
Iwan
I
Eurad Consult International Teleradiology Centre, Mechelen, Belgium. iwanvbreuseghem@yahoo.com
Palmieri
Francesco
F
Peeters
Ronald R
RR
Maes
Frederik
F
Bosmans
Hilde T C
HT
Marchal
Guy J
GJ
D000293:Adolescent; D000328:Adult; D002358:Cartilage, Articular / Q000033:anatomy & histology*; D005260:Female; D005269:Femur; D019786:Gadolinium DTPA; D006801:Humans; D007719:Knee Joint / Q000033:anatomy & histology; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D013977:Tibia
D019786:Gadolinium DTPA