Static and dynamic MR imaging in the evaluation of temporomandibular disorders.

OBJECTIVE The aim of this study is to prove if dynamic HASTE (half-Fourier acquisition single-shot turbo spin-echo) sequences can be used in the diagnosis of internal derangement disorders of temporomandibular joint (TMJ) as an alternative to static proton density (PD) weighted/turbo spin echo (TSE) T2-weighted sequences which are considered up to now as the gold standard in the evaluation of TMJ disorders (TMDs). PATIENTS AND METHODS 194 patients for a total of 388 TMJs were examined with a 1.5 Tesla field strength superconducting magnet. Sagittal static PD-weighted/TSE T2-weighted and dynamic HASTE sequences have been used. Three experts in the field of oral radiology (specialist A, B and C) independently and blinded to clinical symptoms and any treatment, assessed the articular disc position in each TMJ (rated as normal or disc displacement with reduction or disc displacement without reduction). The agreement between static and dynamic images and between the three different specialists in the assessment of the articular disc position was evaluated using kappa statistic. RESULTS The agreement between static and dynamic images is: for specialist A, K = 0.862; for specialist B, K = 0.870 and for specialist C, K = 0.862. CONCLUSIONS Since there is no complete agreement between these two MR techniques, dynamic sequences can not be used as a reliable alternative to static sequences in the evaluation of internal derangement disorders of TMJ.