[RMI of dysfunctional temporomandibular joint (TMJ). Value of gradient-echo T1 sequences in the evaluation of bony structures].
OBJECTIVE
To identify and classify the different types of bony changes of the condyles in patients with disorders of the temporomandibular joint (TMJ).


METHODS
Since 1993, we have imaged over 600 patients with 0.5T MR unit by using gradient-echo T1-weighted sequences in the sagittal and coronal planes.


RESULTS
We will first describe the appearance of the normal TMJ. Then, we will introduce the concept of "Condylo-diskal disunion" using a three grade classification system. We will then describe three patterns of condylar changes: adaptive remodeling, either anterior or more frequently posterior, degenerative lesions with subchondral sclerosis, erosive lesions due to synovial hyperplasia.


CONCLUSIONS
Using a 0.5T MR unit, a GRE T1 sequence is useful to identify lesions of the disk and detect bony changes. In addition, the tissues posterior to the disk can also be assessed on postcontrast images.
Sarrat
P
P
Service de Radiologie et d'Imagerie Médicale, Hôpital Saint Joseph, Marseille.
Cheynet
F
F
Chossegros
C
C
Orthlieb
J D
JD
Philip
E
E
Carrasset
S
S
Bayle
O
O
D003937:Diagnosis, Differential; D006801:Humans; D006965:Hyperplasia; D008279:Magnetic Resonance Imaging / Q000295:instrumentation / Q000379:methods; D013585:Synovitis / Q000175:diagnosis; D013704:Temporomandibular Joint / Q000033:anatomy & histology / Q000473:pathology; D013706:Temporomandibular Joint Dysfunction Syndrome / Q000175:diagnosis* / Q000473:pathology
IRM de l'articulation temporo-mandibulaire (ATM) dysfonctionnelle. Intérêt des séquences en écho de gradient pondéré T1 pour l'analyse des structures osseuses.