TM Joint MRI Protocol

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• Axial T1 SE
• SAG OBL STIR
• Sagittal PD FSE (open mouth)
• Sagittal PD FSE (closed mouth)
• Coronal PD FSE (closed mouth)
• Coronal PD FSE 

  
  

  (open mouth)
  

  
  

  
  

  
  

  
  
• SAG FLASH GRE (closed mouth)
• SAG FLASH GRE (open mouth)

IF DEDICATED TMJ COIL

• SAG OBL MEDIC 
• (closed mouth)

Technical Notes of "TM Joint MRI Protocol":

• Axial T1 spin echo; coronal and sagittal PD fast spin echo through the temporomandibular joints, in both the closed- and open-mouth positions. Dont use oblique positions in open and closed and perform as a straight sagittal (because of change in position of the joints during mouth opening)
• The inherent contrast of the anatomy in the region makes T1-weighed images adequate in most cases.  T2-weighted images are useful when joint fluid, tumor, edema or infections are suspected
• The important landmarks for assessment of TMJ function include the articular fossa of the temporal bone, the mandibular condyle, the disk, and the bilaminar zone.
• The closed-mouth scans are examined first. 
•  Gradient-echo techniques have been implemented to obtain cine-loop motion studies. Three-dimensional volume acquisitions allow a volume of tissue to be imaged rapidly and subsequently viewed in any plane. The use of intra-articular and intravenous gadolinium may provide utility in certain clinical instances-for instance, the inflamed synovium or an inflamed arthropathy will avidly enhance after the administration of intravenous gadolinium
• Normally the disk and the condyle move as a unit anteriorly when the mouth opens,if when the mouth is opened, the condyle and the disk do not resume their normal relationship, anterior displacement without reduction is present

The mandibular condyle is centered on the glenoid fossa when the mouth is closed. When the mouth is open, the condyle moves anteriorly under the center of the articular eminence. 

The disc has anterior (A) and posterior (P) bands. The thinner central portion is called the intermediate zone (iz). The posterior band is normally located directly on top of the condyle (C) when the mouth is closed. The intermediate zone should be between the condyle and the closest portion of the temporal bone in any mouth position. The disc is low signal on all MR sequences, but you may be able to see intermediate signal centrally in the anterior and posterior bands. 

The posterior aspect of the disc attaches to the bilaminar zone, collagen fibers that pull the disc back when it moves forward.

Read more:

Temporomandibular joint Anatomy(T-M Joint Anatomy)

MRI TM joint Benifits & Common Positive Findings
TM joint MRI Reference lines
Dynamic MRI  imaging of the TM joint