title: The value of contrast enhanced power Doppler ultrasonography in differentiating hypoehoic lesions in the peripheral zone of prostate.
abstract: OBJECTIVE
  To characterize the hypoechoic prostate nodules in the peripheral zone by means of power Doppler ultrasonography (PDUS) and contrast enhanced PDUS (CE-PDUS).
  
  
  METHODS
  Thirty-two patients with dijital rectal examination findings suspicious for malignancy and/or a serum PSA level higher than 4 ng/dl, and who had hypoechoic nodules on transrectal ultrasonography were enrolled in this prospective study. Power Doppler ultrasonography (PDUS) images before and after sonocontrast (Levovist) injection were photographed for further evaluation. All patients were also evaluated by a systematic and nodule targeted biopsy approach. The photographs were re-evaluated by two radiologists for the presence and type of vascularity. The type of vascularity was categorized as peripheral, central, mixed and penetrating. The latter two were accepted as representatives of malignancy. The results of PDUS and CE-PDUS were compared to each other and to the pathological results.
  
  
  RESULTS
  There was a high level of interobserver agreement (Kappa: 0.80-0.95). Nineteen patients, but only 14 nodules were malignant on pathological examination. Sensitivity, specificity positive and negative predictive values for PDUS were 57, 50, 47, and 60%, respectively. On CE-PDUS, the sensitivity increased (93%) in expense of specifity (17%). The positive and negative predictive values were 46 and 75%, respectively. There was no significant difference between PDUS and CE-PDUS.
  
  
  CONCLUSIONS
  This study revealed that both benign and malignant nodules might be hypervascular and show malignant type of vascularity on PDUS. Contrary to some recent reports, we can conclude that the CE-PDUS does not provide a considerable aid to the diagnosis of prostate carcinoma on morphological basis due to its very low specificity despite its relatively higher sensitivity.
authors.affiliation: Department of Radiology 09100, Faculty of Medicine, Adnan Menderes University, Aydin, Turkey. zkaraman@adu.edu.tr
authors.forename: Can Zafer
authors.initials: CZ
authors.lastname: Karaman
authors.forename: Alparslan
authors.initials: A
authors.lastname: Unsal
authors.forename: Alev
authors.initials: A
authors.lastname: Akdilli
authors.forename: Füsun
authors.initials: F
authors.lastname: Taşkin
authors.forename: Haluk
authors.initials: H
authors.lastname: Erol
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D003287:Contrast Media; D003937:Diagnosis, Differential; D006801:Humans; D008297:Male; D008875:Middle Aged; D011134:Polysaccharides; D011237:Predictive Value of Tests; D011446:Prospective Studies; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000098:blood supply / Q000000981:diagnostic imaging*; D012007:Rectum; D012680:Sensitivity and Specificity; D018608:Ultrasonography, Doppler
chemical_list: D003287:Contrast Media; D011134:Polysaccharides; C059891:SHU 508; D017430:Prostate-Specific Antigen