title: Contrast-Enhanced Subharmonic and Harmonic Ultrasound of Renal Masses Undergoing Percutaneous Cryoablation.
abstract: OBJECTIVE
  The objective of this study was to evaluate and compare contrast-enhanced subharmonic and harmonic ultrasound as tools for characterizing solid renal masses and monitoring their response to cryoablation therapy.
  
  
  METHODS
  Sixteen patients undergoing percutaneous ablation of a renal mass provided informed consent to undergo ultrasound examinations the morning before and approximately 4 months after cryoablation. Ultrasound contrast parameters during pretreatment imaging were compared to biopsy results obtained during ablation (n = 13). Posttreatment changes were evaluated by a radiologist and compared to contrast-enhanced magnetic resonance imaging (MRI)/computed tomography (CT) follow-up.
  
  
  RESULTS
  All masses initially showed heterogeneous enhancement with both subharmonic and harmonic ultrasound. Early contrast washout in the mass relative to the cortex was observed in 6 of 9 malignant and 0 of 4 benign lesions in subharmonic mode and 8 of 9 malignant and 1 of 4 benign lesions in harmonic imaging. In cases where the lesion was adequately visualized at follow-up (n = 12), subharmonic and harmonic ultrasound showed accuracies of 83% and 75%, respectively, in predicting treatment outcome. Although harmonic imaging showed less overall error, no significant differences (P > .29) in ablation cavity volumes were observed between MRI/CT and either contrast-imaging mode.
  
  
  CONCLUSIONS
  Subharmonic and harmonic contrast-enhanced ultrasound may be a safe and accurate imaging alternative for characterizing renal masses and evaluating their response to cryoablation therapy. Although subharmonic imaging was more accurate in detecting effective cryoablation, harmonic imaging was superior in quantifying ablation cavity volumes.
authors.affiliation: Department of Radiology, Sidney Kimmel Medical College at Thomas Jefferson University, 132 South 10th St, Philadelphia, PA 19107. Electronic address: john.eisenbrey@jefferson.edu.
authors.forename: John R
authors.initials: JR
authors.lastname: Eisenbrey
authors.affiliation: Department of Radiology, Sidney Kimmel Medical College at Thomas Jefferson University, 132 South 10th St, Philadelphia, PA 19107.
authors.forename: Colette M
authors.initials: CM
authors.lastname: Shaw
authors.affiliation: Department of Radiology, Sidney Kimmel Medical College at Thomas Jefferson University, 132 South 10th St, Philadelphia, PA 19107.
authors.forename: Andrej
authors.initials: A
authors.lastname: Lyshchik
authors.affiliation: Department of Radiology, Sidney Kimmel Medical College at Thomas Jefferson University, 132 South 10th St, Philadelphia, PA 19107.
authors.forename: Priscilla
authors.initials: P
authors.lastname: Machado
authors.affiliation: Department of Urology, Sidney Kimmel Medical College at Thomas Jefferson University, Philadelphia, Pennsylvania.
authors.forename: Costas D
authors.initials: CD
authors.lastname: Lallas
authors.affiliation: Department of Urology, Sidney Kimmel Medical College at Thomas Jefferson University, Philadelphia, Pennsylvania.
authors.forename: Edouard J
authors.initials: EJ
authors.lastname: Trabulsi
authors.affiliation: Department of Radiology, Sidney Kimmel Medical College at Thomas Jefferson University, 132 South 10th St, Philadelphia, PA 19107.
authors.forename: Daniel A
authors.initials: DA
authors.lastname: Merton
authors.affiliation: Department of Radiologic Sciences, Jefferson College of Health Professions, Thomas Jefferson University, Philadelphia, Pennsylvania.
authors.forename: Traci B
authors.initials: TB
authors.lastname: Fox
authors.affiliation: Department of Radiology, Sidney Kimmel Medical College at Thomas Jefferson University, 132 South 10th St, Philadelphia, PA 19107.
authors.forename: Ji-Bin
authors.initials: JB
authors.lastname: Liu
authors.affiliation: Department of Radiology, Sidney Kimmel Medical College at Thomas Jefferson University, 132 South 10th St, Philadelphia, PA 19107.
authors.forename: Daniel B
authors.initials: DB
authors.lastname: Brown
authors.affiliation: Department of Radiology, Sidney Kimmel Medical College at Thomas Jefferson University, 132 South 10th St, Philadelphia, PA 19107.
authors.forename: Flemming
authors.initials: F
authors.lastname: Forsberg
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000418:Albumins; D002292:Carcinoma, Renal Cell / Q000000981:diagnostic imaging* / Q000601:surgery*; D003287:Contrast Media; D003452:Cryosurgery / Q000379:methods*; D005260:Female; D005466:Fluorocarbons; D006498:Hepatectomy / Q000379:methods; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007680:Kidney Neoplasms / Q000000981:diagnostic imaging* / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D025321:Surgery, Computer-Assisted / Q000379:methods*; D016896:Treatment Outcome; D014463:Ultrasonography
chemical_list: D000418:Albumins; D003287:Contrast Media; C099458:FS 069; D005466:Fluorocarbons
keywords: Contrast-enhanced ultrasound; cryoablation; renal cell carcinoma; subharmonics