title: Parotid Lymphadenopathy Is Associated With Joint Effusion in Non-Neoplastic Temporomandibular Disorders.
abstract: OBJECTIVE
  Lymphadenopathy often occurs in the setting of inflammation, with or without infection. We sought to elucidate any association of parotid lymphadenopathy with joint effusion in temporomandibular joint (TMJ) disorders.
  
  
  METHODS
  We performed a retrospective cohort study. We analyzed the magnetic resonance imaging studies of patients with suspected TMJ disorders performed from April 2006 to March 2007. The degree of joint effusion was graded on sagittal T2-weighted spin echo images according to a commonly used system. On axial short T1-weighted short inversion recovery images, the number and short-axis diameter of the parotid lymph nodes were recorded. We performed analyses of the cluster-correlated data using the Mann-Whitney U test and Spearman's correlation coefficients. P < .05 was considered to indicate significance. To assess the possible predictive value of certain variables, a generalized linear model (generalized estimation equation) was constructed, considering the multiple measurements.
  
  
  RESULTS
  A total of 402 TMJ disorders were analyzed from 201 patients during the study period. The number and size of the parotid lymph nodes identified was significantly greater in the patients with TMJ effusion (P < .01) than in those without effusion.
  
  
  CONCLUSIONS
  In the present study, we found an association between parotid lymphadenopathy and joint effusion in TMJ disorders. These findings indicate that lymphadenopathy should be considered as an inflammation condition commonly associated with joint effusion in TMJ disorders.
authors.affiliation: Graduate Student, Department of Radiology, Nihon University School of Dentistry, Matsudo, Japan. Electronic address: mahi13020@g.nihon-u.ac.jp.
authors.forename: Hirotaka
authors.initials: H
authors.lastname: Muraoka
authors.affiliation: Professor, Department of Radiology, Nihon University School of Dentistry, Matsudo, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Kaneda
authors.affiliation: Research Associate, Department of Radiology, Nihon University School of Dentistry, Matsudo, Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Kawashima
authors.affiliation: Graduate Student, Department of Radiology, Nihon University School of Dentistry, Matsudo, Japan.
authors.forename: Naohisa
authors.initials: N
authors.lastname: Hirahara
authors.affiliation: Graduate Student, Department of Radiology, Nihon University School of Dentistry, Matsudo, Japan.
authors.forename: Taiga
authors.initials: T
authors.lastname: Fukuda
authors.affiliation: Research Associate, Department of Radiology, Nihon University School of Dentistry, Matsudo, Japan.
authors.forename: Teruaki
authors.initials: T
authors.lastname: Muramatsu
authors.affiliation: Research Associate, Department of Radiology, Nihon University School of Dentistry, Matsudo, Japan.
authors.forename: Kotaro
authors.initials: K
authors.lastname: Ito
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D006833:Hydrarthrosis / Q000000981:diagnostic imaging / Q000209:etiology* / Q000473:pathology; D000072281:Lymphadenopathy / Q000000981:diagnostic imaging / Q000209:etiology* / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D010306:Parotid Gland / Q000000981:diagnostic imaging / Q000473:pathology*; D012189:Retrospective Studies; D013705:Temporomandibular Joint Disorders / Q000150:complications* / Q000000981:diagnostic imaging / Q000473:pathology