title: Contrast-enhanced ultrasound imaging of sentinel lymph nodes after peritumoral administration of Sonazoid in a melanoma tumor animal model.
abstract: OBJECTIVE
  The purpose of this study was to compare lymphosonography (ie, contrast-enhanced ultrasound imaging [US] after interstitial injection of a US contrast agent) for the detection of sentinel lymph nodes (SLNs) in swine with naturally occurring melanoma tumors to lymphoscintigraphy using blue dye-guided surgical dissection as the reference standard. Also, we sought to determine if lymphosonography can be used to characterize SLNs.
  
  
  METHODS
  Sixty-three swine with 104 melanomas were evaluated. Contrast-specific US was performed after peritumoral injection (1 mL dose) of Sonazoid (GE Healthcare, Oslo, Norway). Lymphoscintigraphy was performed after peritumoral injections of technetium Tc 99m sulfur colloid. Peritumoral injection of 1% Lymphazurin (Ben Venue Labs, Inc, Bedford, OH) was used to guide SLN resection. The accuracy of SLN detection with the two imaging modalities was compared using the McNemar test. The SLNs were qualitatively and quantitatively characterized as benign or malignant based on the lymphosonography results with histopathology and RNA analyses used as the reference standards.
  
  
  RESULTS
  Blue dye-guided surgery identified 351 SLNs. Lymphosonography detected 293 SLNs and 11 false-positives, while lymphoscintigraphy detected 231 SLNs and 20 false-positives. The accuracy of SLN detection was 81.8% for lymphosonography, which was significantly higher than the 63.2% achieved with lymphoscintigraphy (P < .0001). The accuracy of lymphosonography for SLN characterization was 80%. When the size of the enhanced SLN was taken into consideration to characterize SLNs, the accuracy was 86%.
  
  
  CONCLUSIONS
  Lymphosonography is statistically better than lymphoscintigraphy for the detection of SLNs in this animal model. The ability to use lymphosonography as a means to characterize SLNs as benign or malignant is limited.
authors: Department of Radiology, Thomas Jefferson University Hospital, Philadelphia, PA 19107, USA.
authors: Barry B
authors: BB
authors: Goldberg
authors: Daniel A
authors: DA
authors: Merton
authors: Ji-Bin
authors: JB
authors: Liu
authors: Flemming
authors: F
authors: Forsberg
authors: Kaijun
authors: K
authors: Zhang
authors: Madhukar
authors: M
authors: Thakur
authors: Stephanie
authors: S
authors: Schulz
authors: Robin
authors: R
authors: Schanche
authors: George F
authors: GF
authors: Murphy
authors: Scott A
authors: SA
authors: Waldman
mesh_terms: D000818:Animals; D016009:Chi-Square Distribution; D004396:Coloring Agents / Q000008:administration & dosage; D003287:Contrast Media / Q000008:administration & dosage; D004195:Disease Models, Animal; D005290:Ferric Compounds / Q000008:administration & dosage; D021621:Imaging, Three-Dimensional; D007501:Iron / Q000008:administration & dosage; D008198:Lymph Nodes / Q000000981:diagnostic imaging* / Q000473:pathology; D008207:Lymphatic Metastasis / Q000000981:diagnostic imaging* / Q000473:pathology; D008545:Melanoma / Q000000981:diagnostic imaging* / Q000473:pathology; D010087:Oxides / Q000008:administration & dosage; D011237:Predictive Value of Tests; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals / Q000008:administration & dosage; D012394:Rosaniline Dyes / Q000008:administration & dosage; D012680:Sensitivity and Specificity; D021701:Sentinel Lymph Node Biopsy; D018709:Statistics, Nonparametric; D013552:Swine; D013671:Technetium Tc 99m Sulfur Colloid / Q000008:administration & dosage; D014463:Ultrasonography; D014743:Videotape Recording
chemical_list: D004396:Coloring Agents; D003287:Contrast Media; D005290:Ferric Compounds; D010087:Oxides; D019275:Radiopharmaceuticals; D012394:Rosaniline Dyes; C069727:Sonazoid; C025484:iso-sulfan blue; D013671:Technetium Tc 99m Sulfur Colloid; D007501:Iron