title: Magnetic resonance signal intensity from retrodiscal tissue related to joint effusion status and disc displacement in elderly patients with temporomandibular joint disorders.
abstract: Magnetic resonance imaging (MRI) on patients with temporomandibular joint disorders (TMD) has revealed that a decrease and/or increase in signal intensity from retrodiscal tissue, joint effusion (the excessive accumulation of joint fluid) and articular disc displacement are related to TMD. However, the effect of aging on these phenomena has yet to be clarified. This study was carried out to explore the relationship between changes in signal intensity from retrodiscal tissue, joint fluid status and pathological disc conditions in elderly patients with TMD. Twenty patients aged over 60 years were examined. They consisted of one man and 19 women, and ranged between 60 and 79 years in age (mean, 66.0 years). The relationships between decreased signal intensity on proton-density-weighted (PDW) images and increased signal intensity on T2-weighted (T2W) MR images from retrodiscal tissue, joint fluid status and state of articular disc were examined. Joint fluid status was classified into 5 levels by extent of high signal areas in upper and lower articular spaces on T2W images. Disc displacement status was evaluated by PDW images. The Wilcoxon test was applied for the statistical analysis. The group showing increased T2W signal intensities from the retrodiscal tissue consisted of 31 out of 40 joints (77.5%). This group showed a significant difference in comparison with the other groups in which no apparent joint fluid was shown (p<0.05). There were no statistically significant differences among other categories. The results suggest a negative relationship between joint fluid and increased signal intensity from retrodiscal tissue due to reflection of the inflammatory reaction in TM joints.
authors.affiliation: Department of Dysphagia Rehabilitation and Community Dental Care, Tokyo Dental College, Mihama-ku, Chiba, Japan.
authors.forename: Mai
authors.initials: M
authors.lastname: Ohkubo
authors.forename: Tsukasa
authors.initials: T
authors.lastname: Sano
authors.forename: Mika
authors.initials: M
authors.lastname: Otonari-Yamamoto
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Hayakawa
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Okano
authors.forename: Kaoru
authors.initials: K
authors.lastname: Sakurai
authors.forename: Toru
authors.initials: T
authors.lastname: Sato
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Sugiyama
authors.forename: Ryo
authors.initials: R
authors.lastname: Ishida
mesh_terms: D000368:Aged; D000375:Aging / Q000502:physiology*; D005260:Female; D006801:Humans; D004204:Joint Dislocations / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D013582:Synovial Fluid; D013704:Temporomandibular Joint / Q000473:pathology / Q000503:physiopathology; D019224:Temporomandibular Joint Disc / Q000473:pathology*; D013705:Temporomandibular Joint Disorders / Q000473:pathology*