title: Enlarged cervical lymph nodes at helical CT.
abstract: OBJECTIVE
  To evaluate criteria for differentiating malignant versus reactive lymph nodes in the head and neck on the basis of findings at helical computed tomography (CT).
  
  
  METHODS
  Helical CT scans were evaluated of 70 consecutive patients (46 men and 24 women, aged 20-78 years [mean, 51 years]) with known head and neck tumors and cervical lymph node enlargement. The ratio of the maximal longitudinal to the maximal axial diameter (L/T) was calculated for nodes larger than 8 mm in diameter based on measurements obtained from coronal, paraxial, and sagittal reconstructions.
  
  
  RESULTS
  At histologic examination, 96 of 164 nodes were malignant. Of these, 94 of 96 nodes had an L/T of less than 2 (sensitivity, 97%; specificity, 97%; accuracy, 97% for malignancy). Minimal diameter was more than 8 mm in 83 of 96 nodes (sensitivity, 87%; specificity, 89%; accuracy, 88% for malignancy). Low-attenuation centers and rim enhancement were seen in 75 of 96 nodes (sensitivity, 78%; specificity, 100%; accuracy, 86% for malignancy).
  
  
  CONCLUSIONS
  The L/T at helical CT provide an accurate assessment of reactive versus malignant nodes in the head and neck.
authors.affiliation: Department of Radiology, Freie Universitat Berlin, Klinikum Rudolf Virchow/Standort Wedding, Germany.
authors.forename: H J
authors.initials: HJ
authors.lastname: Steinkamp
authors.forename: N
authors.initials: N
authors.lastname: Hosten
authors.forename: C
authors.initials: C
authors.lastname: Richter
authors.forename: H
authors.initials: H
authors.lastname: Schedel
authors.forename: R
authors.initials: R
authors.lastname: Felix
mesh_terms: D000328:Adult; D000368:Aged; D003937:Diagnosis, Differential; D005188:False Negative Reactions; D005189:False Positive Reactions; D005260:Female; D006801:Humans; D008198:Lymph Nodes / Q000000981:diagnostic imaging*; D008207:Lymphatic Metastasis / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D009333:Neck / Q000000981:diagnostic imaging*; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed