title: Enhancement characteristics of retroperitoneal lymphomatous lymph nodes.
abstract: BACKGROUND
  Previous studies of CT enhancement of lymphomatous lymph nodes (LLN) of the neck and the mediastinum showed that the LLN had lower enhancement values than normal lymph nodes.
  
  
  OBJECTIVE
  To elucidate the contrast medium enhancement curves of LLN in the retroperitoneum by comparing the curves of LLN with those of normal lymph nodes, to test whether differences between these curves could be of diagnostic value, and to compare the present enhancement curves of LLN of the retroperitoneum with the curves of LLN of the neck and the mediastinum from previous similar investigations.
  
  
  METHODS
  Twenty-eight consecutive patients with LLN of the retroperitoneum (three with Hodgkin's lymphoma [HL]) and 21 control patients with sarcomas and thus presumably normal retroperitoneal nodes underwent dynamic CT examinations. The previous, similar investigation of lymph nodes of the neck comprised 28 patients with LLN and the investigation of mediastinal lymph nodes comprised 24 patients with LLN.
  
  
  RESULTS
  The enhancement curves of the retroperitoneal LLN had significantly lower attenuation than those of the retroperitoneal control nodes. A combination of peak contrast value and time to peak adjusted to total body weight yielded a diagnostic accuracy which at the best showed a sensitivity of 90.5% with a specificity of 82.6%. The LLN of the retroperitoneum had higher attenuation values than corresponding nodes of the mediastinum but no significant difference was found between LLN of the retroperitoneum and LLN of the neck in previous similar investigations.
  
  
  CONCLUSIONS
  The comparison of enhancement curves of retroperitoneal LLN with retroperitoneal control nodes showed a marked similarity with and substantiates our previous findings in lymph nodes of the neck and of the mediastinum. The best diagnostic accuracy was achieved by combining the parameters peak contrast value and time to peak and adjusting these values to the body weight. Peak enhancement of the retroperitoneal LLN was higher and arrived earlier than that of the mediastinal nodes from the previous investigation.
authors: Department of Radiology and Nuclear Medicine, Oslo University Hospital, Oslo, Norway.
authors: Trond
authors: T
authors: Hagtvedt
authors: Trond Mogens
authors: TM
authors: Aaløkken
authors: Hans-Jørgen
authors: HJ
authors: Smith
authors: Bjørn Anton
authors: BA
authors: Graff
authors: Harald
authors: H
authors: Holte
authors: Alf
authors: A
authors: Kolbenstvedt
mesh_terms: D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D003287:Contrast Media; D005260:Female; D006689:Hodgkin Disease / Q000000981:diagnostic imaging* / Q000473:pathology; D006801:Humans; D007472:Iohexol; D016015:Logistic Models; D008198:Lymph Nodes / Q000000981:diagnostic imaging*; D008228:Lymphoma, Non-Hodgkin / Q000000981:diagnostic imaging* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D012372:ROC Curve; D012187:Retroperitoneal Space / Q000000981:diagnostic imaging*; D012680:Sensitivity and Specificity; D036542:Tomography, Spiral Computed / Q000379:methods*
chemical_list: D003287:Contrast Media; D007472:Iohexol