title: Value of computed tomography findings in differentiating between intraosseous malignant tumors and osteomyelitis of the mandible affecting the masticator space.
abstract: OBJECTIVE
  We sought to evaluate the diagnostic efficacy of computed tomography (CT) images in the differentiation between intraosseous malignant tumors and osteomyelitis spreading into the masticator space.
  
  
  METHODS
  A retrospective evaluation was carried out by using CT images from 12 patients with intraosseous malignant tumors and 9 patients with osteomyelitis involving the masticator space and accompanying mandibular bone destruction. The following CT observations are discussed: (1) bone destruction pattern subdivided into spotty, gross, or permeative; (2) cortical bone expansion; (3) diffuse osteosclerotic changes; (4) periosteal reaction; (5) masticator muscle involvement; (6) enlargement of the facial muscle; and (7) attenuation in the subcutaneous adipose tissue.
  
  
  RESULTS
  The pattern of permeative bone destruction, cortical bone expansion, and the enlargement of both the masseter and medial pterygoid muscles were all observed in patients with malignant tumors. In contrast, diffuse sclerotic change and a periosteal reaction were significant observations in patients with osteomyelitis.
  
  
  CONCLUSIONS
  The efficacy of CT in establishing a differential diagnosis of malignant tumors or osteomyelitis is supported by this study.
authors.affiliation: Department of Oral Surgery, Sapporo Medical University School of Medicine, Sapporo, Japan.
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Hariya
authors.forename: Kenji
authors.initials: K
authors.lastname: Yuasa
authors.forename: Eiji
authors.initials: E
authors.lastname: Nakayama
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Kawazu
authors.forename: Kazutoshi
authors.initials: K
authors.lastname: Okamura
authors.forename: Shigenobu
authors.initials: S
authors.lastname: Kanda
mesh_terms: D000273:Adipose Tissue / Q000000981:diagnostic imaging; D000328:Adult; D000368:Aged; D003937:Diagnosis, Differential; D005152:Facial Muscles / Q000000981:diagnostic imaging; D006801:Humans; D006984:Hypertrophy; D008336:Mandibular Diseases / Q000145:classification / Q000000981:diagnostic imaging*; D008339:Mandibular Neoplasms / Q000000981:diagnostic imaging*; D008406:Masseter Muscle / Q000000981:diagnostic imaging; D008875:Middle Aged; D009135:Muscular Diseases / Q000000981:diagnostic imaging; D010019:Osteomyelitis / Q000145:classification / Q000000981:diagnostic imaging*; D010026:Osteosclerosis / Q000000981:diagnostic imaging; D010521:Periosteum / Q000000981:diagnostic imaging; D011626:Pterygoid Muscles / Q000000981:diagnostic imaging; D012189:Retrospective Studies; D013223:Statistics as Topic; D014057:Tomography, X-Ray Computed