From the Guidelines
The best MRI to evaluate the jaw is a dedicated maxillofacial MRI protocol with thin-slice (1-3mm) T1-weighted, T2-weighted, and fat-suppressed sequences, using a high-field strength magnet (1.5T or 3T) and contrast administration with gadolinium, as recommended by the most recent study 1. This protocol should be performed using a dedicated surface coil placed over the jaw region, and include axial, coronal, and sagittal planes to provide comprehensive visualization of the temporomandibular joints, mandibular condyles, rami, body, and symphysis.
- The use of contrast-enhanced MRI is currently the best method to detect active TMJ arthritis, as stated in the 2023 study 1.
- Dynamic imaging during jaw opening and closing may be added when evaluating temporomandibular joint disorders.
- For dental-related pathology, the protocol may be supplemented with specialized dental MRI sequences that reduce metal artifacts from dental work. The protocol should prioritize the assessment of bone marrow abnormalities, soft tissue involvement, nerve pathways, and vascular structures, as these are critical for evaluating jaw pathologies, as noted in the study 1.
- The interpretation of MRI findings should be done with caution, considering the subjectivity and influence of technique, equipment, and reader expertise, as highlighted in the 2023 study 1.
- Standardization of image acquisition and interpretation is necessary to ensure accurate diagnosis and treatment, as emphasized in the study 1.
From the Research
MRI Sequences for Jaw Evaluation
The following MRI sequences have been studied for their effectiveness in evaluating the jaw:
- Proton density-weighted turbo spin echo sequences 2
- T1-weighted fast spin-echo sequence (T1-weighted FSE) 3
- T2-weighted fast spin-echo sequence (T2-weighted FSE) 3
- Multiple-echo recombined gradient echo (MERGE) 3
- Dynamic HASTE (half-Fourier acquisition single-shot turbo spin-echo) sequences 4
- 3D fast spoiled gradient echo recalled sequence (3D FSPGR) 5
Field Strength for Jaw Evaluation
Research suggests that imaging at 3.0 T should be preferred over 1.5 T for imaging the temporomandibular joint (TMJ) due to increased visibility and delineation of anatomical structures 2.
Image Quality and Diagnostic Accuracy
Studies have shown that:
- MERGE is better for visualizing the condylar only at the middle and the medial aspects of the TMJ in a normally positioned disk 3
- Dynamic sequences cannot be used as a reliable alternative to static sequences in the evaluation of internal derangement disorders of TMJ 4
- 3D FSPGR sequence is the most reliable MRI sequence to assess the cortical bone of the mandibular condyles on sagittal imaging planes 5
- A generative adversarial network (GAN) model can synthesize T2-weighted images from proton density images with high diagnostic accuracy 6