title: Visual perception of multilocular radiolucent mandibular lesions quantified by morphometric analysis.
abstract: OBJECTIVE
  The aim of this study was to analyse the visual perceptions of different experts with respect to multilocular radiolucent lesions in circumstances when the diagnosis is either known or unknown.
  
  
  METHODS
  6 radiographs of ameloblastomas (AMELs), keratocystic odontogenic tumours (KOTs), central giant cell lesions (CGCLs) and myxomas (MIXs) were analysed by 16 dental experts [stomatologists/oral surgeons (SS) and dental radiologists (R)]. They delimited the lesions prior to having knowledge of the diagnosis (T1) and after 30 days, when they were aware of the histopathological results (T2). For each image, the following morphometric parameters were calculated: area (A), perimeter (P) and shape factor (SF); after image subtraction procedures (T1 - T2), the exclusive area (EA) of the non-overlapping delimited region was also calculated.
  
  
  RESULTS
  For both groups, the T2 area was larger than the T1, although the EA of the SS group was higher than that of the R group independently of the type of lesion. The SF from the SS group was greater than that from the R group, and at T2 the SF values were higher for both groups. AMELs and MIXs showed larger SF and A values; the SS group tended to have the greatest changes in the delimitations of the lesions at T2.
  
  
  CONCLUSIONS
  The methodology allowed us to quantify differences in the spatial perceptions of professionals. The knowledge of the diagnosis and the expertise of examiners influenced the examiner's perception of the limits of the lesions independently of the actual biological behaviour of the lesion.
authors: São Leopoldo Mandic, Dental Research Insitute, Campinas, São Paolo, Brazil. ricardoraitz@ig.com.br
authors: R
authors: R
authors: Raitz
authors: A L V
authors: AL
authors: Rodrigues
authors: V C R
authors: VC
authors: Reis
authors: R C
authors: RC
authors: Borra
mesh_terms: D000564:Ameloblastoma / Q000000981:diagnostic imaging; D000704:Analysis of Variance; D005870:Giant Cell Tumors / Q000000981:diagnostic imaging; D006801:Humans; D008339:Mandibular Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology*; D009232:Myxoma / Q000000981:diagnostic imaging; D009361:Neoplasm Invasiveness / Q000473:pathology*; D015588:Observer Variation; D009808:Odontogenic Tumors / Q000000981:diagnostic imaging; D011856:Radiographic Image Enhancement; D018709:Statistics, Nonparametric; D013382:Subtraction Technique; D014796:Visual Perception