title: Contrast enhanced high resolution MRI of cutaneous melanomas using Gd-DTPA and Gd-DTPA-polylysine: experimental results.
abstract: OBJECTIVE
  An experimental model for the preclinical evaluation of contrast enhancement patterns in melanoma was developed.
  
  
  METHODS
  Melanotic and amelanotic tumor cells B16F1 and B16a implanted into murine skin were depicted with magnetic resonance imaging (MRI) at a pixel size of 78×78 urn and 1 mm slice thickness. Tumor signal intensities were evaluated in user defined ROIs (regions of interest). Signal intensity changes were determined from signal intensity-time curves. Percent enhancement, slope of the signal intensity curve and percent signal intensity increase were also determined. Percent enhancement was calculated: (SIenhanced -SIpiain )/SIplain × 100 [SI=signal intensity]. The slope of the signal intensity curve was calculated: (SImax -SIplain )/(SIplain × SImax ) × 100 (%/min). Percent signal intensity increase was calculated: (SImax -SIplai )/SIplain × 100.
  
  
  RESULTS
  Following i.v. administration of Gd-DTPA and G-DTPA-polylysine, all tumors showed pronounced contrast enhancement. Contrast enhancement and the slope of signal intensity to time curves did not distinguish melanotic from amelanotic melanomas (P>0.05).
  
  
  CONCLUSIONS
  The animal model presented is well suited for evaluation of contrast enhancement in melanoma by MRI. Contrast enhancement of melanoma in MRI is comparable with the enhancement seen in other tumors.
authors.affiliation: Strahlenklinik und Poliklinik, Virchow-Klinikum, Humboldt-Universität zu BerlinResearch Laboratories of Schering, Schering AG, Berlin, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Mäurer
authors.affiliation: Strahlenklinik und Poliklinik, Virchow-Klinikum, Humboldt-Universität zu BerlinResearch Laboratories of Schering, Schering AG, Berlin, Germany.
authors.forename: F D
authors.initials: FD
authors.lastname: Knollmann
authors.affiliation: Strahlenklinik und Poliklinik, Virchow-Klinikum, Humboldt-Universität zu BerlinResearch Laboratories of Schering, Schering AG, Berlin, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Veuskens
authors.affiliation: Strahlenklinik und Poliklinik, Virchow-Klinikum, Humboldt-Universität zu BerlinResearch Laboratories of Schering, Schering AG, Berlin, Germany.
authors.forename: W
authors.initials: W
authors.lastname: Ebert
authors.affiliation: Strahlenklinik und Poliklinik, Virchow-Klinikum, Humboldt-Universität zu BerlinResearch Laboratories of Schering, Schering AG, Berlin, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Bauer
authors.affiliation: Strahlenklinik und Poliklinik, Virchow-Klinikum, Humboldt-Universität zu BerlinResearch Laboratories of Schering, Schering AG, Berlin, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Felix
keywords: Gd-DTPA; Gd-DTPA-polylysine; MRI; contrast medium; high resolution; melanoma