Detection of the Temporomandibular Joint Fibrocartilage by Magnetic Resonance Imaging

Objective: The aims of this study were to detect the fibrocartilage layer (FC) of the porcine mandible condyle in ex vivo preparations using 3D SPGR (Spoiled GRASS sequence) (T1 WATS) sequences, and, to compare 3D SPGR image results with those of conventional magnetic resonance imaging (MRI) sequences for detecting the fibrocartilage layers of the temporomandibular joint (TMJ) in patients with temporomandibular disorders (TMD). Methods: Four porcine TMJ with and without FC were radiographically and histologically assessed. Additionally, fifty-nine patients were studied using T1 WATS MRI and T2 TSE and PD TSE sequences. Four trained and calibrated observers assessed the MRI images. Results: In porcine, the T1 WATS sequence was able to detect the presence or absence of FC in the mandibular condyle, histologically confirmed. In humans, 98% of fibrocartilages were detected with T1 WATS sequence in temporal fossa, and 91% in mandible condyles. Significantly poorer detection with the T2 TSE and PD TSE sequences was observed. Mean fibrocartilage ROI signal intensity was 74.07 IU (±14.7), without statistical differences between fossa and condyle. Conclusion: T1 WATS is the most reliable and efficient sequence for detecting the TMJ fibrocartilage layer (p <0.05).