” Post hoc pair-wise comparisons were performed using a Bonferroni correction. A p value equal to or below p = 0.05 was considered to indicate significant results. The 2D inversion recovery sequences show a statistically significant drop (p < 0.001) in T1 from pre-contrast (T10 = 688.5 ms) to 30 minutes post-contrast (p < 0.001; T130 = 396.9 ms), and to 60 minutes post-contrast (p < 0.001; T160 = 341.4 ms),

as well as from T1 pre-contrast to 120 minutes post-contrast (p < 0.001; T1120 = 351.9 ms). A T1 drop of 50% was reached at time point 2, which was 60 minutes PLX3397 order after contrast agent administration ( Fig. 5 and Fig. 6). The 3D gradient echo sequences confirmed these results, with a significant drop in T1 between time point 0 and time point 1 (p < 0.001, T10 = 992.1 ms, T110 = 855.9 ms), and reaching

a T1 drop of 50% between time points 6 (T160 = 516.9 ms) and 7 (T170 = 489.7 ms), after contrast agent administration (Table 1, Fig. 6). When the 2D inversion recovery sequences were analyzed for differences within the TMJ disc, interestingly, all six TMJ discs showed the lowest T1 values in the anterior portion of the disc. In the central and posterior part of the disc, the results were heterogeneous. The tendency toward higher T1 values for the Thiazovivin left TMJ can be explained by measurement time points – the left TMJ was measured first by default. Despite known risk for NSF, as a side effect of dGEMRIC, we did not observe any complications after intra-venous contrast agent administration. To our knowledge, no attempt has been made to test the feasibility of dGEMRIC for GAG-specific biochemical MR imaging in the fibrocartilaginous disc of the TMJ to date. One recent case study of two volunteers and one cadaver focused on T2* values of the TMJ disc [26]. Recently, quantitative evaluation of the T1 relaxation times of the menisci following (Gd-DTPA)2- administration was used to assess the potential of this technique

for the detection of degenerative changes in fibrocartilage [31]. Long-term contrast agent kinetics of (Gd-DTPA)2- in the menisci were measured in another study in asymptomatic volunteers for nine hours, with a suggested suitable time-window between 2.5 and 4.5 hours after contrast agent administration [32]. In our study, the optimal time find more window after i.v. contrast agent administration was between 60 and 120 minutes, which may be due to the different anatomical conditions (upper and lower joint space for contrast agent penetration compared to hyaline cartilage with only one surface to the joint space) and the more sensitive region of the TMJ area. T1 reference values from knee cartilage (T1(Gd) = 636.0 ± 181.0 ms) [33] and from meniscal tissue (T1(Gd), 90 minutes after contrast agent administration = 660.0 ± 93. 8 ms) [34], are higher compared to our results in the fibrocartilaginous TMJ disc (T1(Gd) = 341.4 ms with 2D inversion recovery and 471.