title: The role of directional power Doppler in vascular characterization of renal masses.
abstract: OBJECTIVE
  The purpose of our study was to characterize the vascularization of frequently detected renal masses with directional power Doppler (dpD).
  
  
  METHODS
  We analyzed 38 renal masses with B-mode sonography (US), dpD, computer tomography (CT) and/or magnetic resonance (MR) and, in some cases, also with percutaneous renal biopsy (RB). The study population included 14 renal cell carcinomas (RCC), 10 angiomyolipomas (AML), 5 other types of lesions, as complex cysts, anatomical malformations and focal pyelonephritis (PLN), 9 mass lesions classified indeterminate by imaging studies and have defied characterization by RB. The dpD evaluated the peri or intra-lesional vessels distribution according to Jinzaki vascular patterns, the presence of artero-venous fistulas (AVF) and Doppler spectrum of these lesions, especially blood-flow systolic peak velocity (SPV).
  
  
  RESULTS
  At US, there was no statistically significant difference in lesion size, but significant difference was found in echogenicity of AML resulted all hyperechoic in respect of other types of lesions. At dpD, the vascular distribution in most of CCRs (11/14) was classified as pattern 3 or 4 (peripheral and mixed penetrating/peripheral, respectively) and was significantly different in respect to AMLs, that showed patterns 1 and 2 (intratumoral focal and penetrating, respectively), in respect to other types of lesions, that were with prevalent pattern 2, and in respect of indeterminate lesions, that presented all patterns (from 1 to 4). The SPV was more elevated in CCRs than in all other types of lesions. Three CCRs presented AVF.
  
  
  CONCLUSIONS
  The dpD adds very important information to simple US in vascular pattern evaluation of small solid renal lesions and improve the diagnostic accuracy.
authors.affiliation: Hospital Unit of Nephrology and Dialysis, Hospital of Polla, Salerno, Italy. pasqualina.disiervi@tiscali.it
authors.forename: Pasqualina
authors.initials: P
authors.lastname: Di Siervi
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Bellizzi
authors.forename: Federico
authors.initials: F
authors.lastname: Pagano
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Terracciano
mesh_terms: D000368:Aged; D005260:Female; D006801:Humans; D007674:Kidney Diseases / Q000000981:diagnostic imaging*; D007680:Kidney Neoplasms / Q000098:blood supply* / Q000000981:diagnostic imaging*; D008297:Male; D008875:Middle Aged; D018608:Ultrasonography, Doppler