title: Evaluation of multimodality imaging using image fusion with MRI and CEUS in an experimental animal model.
abstract: OBJECTIVE
  To evaluate the diagnostic benefits of multimodality imaging using image fusion with magnetic-resonance-imaging (MRI) and contrast-enhanced-ultrasound (CEUS) in an experimental small-animal-squamous-cell-carcinoma-model for the assessment of tissue hemodynamics and morphology.
  
  
  METHODS
  Human hypopharynx-carcinoma-cells were injected subcutaneously into the left flank of 15 female athymic nude rats. After 10 daysof subcutaneous tumor growth, CEUS and MRI measurements were performed using a high-end-ultrasound-system and 3-T-MRI. After successful point-to-point or plan registration, the registered MR-images were simultaneously shown with the respective ultrasound sectional plane. Data evaluation was performed using the digitally stored video sequence data sets by two experienced radiologists using a subjective 5-point scale.
  
  
  RESULTS
  CEUS and MRI are well-known techniques for the assessment of tissue hemodynamics (score: mean 3.8 ± 0.4 SD and score 3.8 ± 0.4 SD). Real-time image fusion of MRI and CEUS yielded a significant (p <  0.001) improvement in score (score 4.8 ± 0.4 SD). Reliable detection of small necrotic areas was possible in all animals with necrotic tumors. No significant intraobserver and interobserver variability was detected (kappa coefficient = +1).
  
  
  CONCLUSIONS
  Image fusion of MRI and CEUS gives a significant improvement for reliable differentiation between different tumor tissue areas and simplifies investigations by showing the morphology as well as surrounding macro-/microvascularization.
authors.affiliation: Institute for Clinical Radiology, Ludwig Maximilian University Hospital, Munich, Germany.
authors.forename: P M
authors.initials: PM
authors.lastname: Paprottka
authors.affiliation: Institute for Ear, Nose and Throat Medicine, Munich, Germany.
authors.forename: P
authors.initials: P
authors.lastname: Zengel
authors.affiliation: Institute for Clinical Radiology, Ludwig Maximilian University Hospital, Munich, Germany.
authors.forename: C C
authors.initials: CC
authors.lastname: Cyran
authors.affiliation: Institute for Clinical Radiology, Ludwig Maximilian University Hospital, Munich, Germany.
authors.forename: K J
authors.initials: KJ
authors.lastname: Paprottka
authors.affiliation: Institute for Clinical Radiology, Ludwig Maximilian University Hospital, Munich, Germany.
authors.forename: M
authors.initials: M
authors.lastname: Ingrisch
authors.affiliation: Institute for Clinical Radiology, Ludwig Maximilian University Hospital, Munich, Germany.
authors.forename: K
authors.initials: K
authors.lastname: Nikolaou
authors.affiliation: Institute for Clinical Radiology, Ludwig Maximilian University Hospital, Munich, Germany.
authors.forename: M F
authors.initials: MF
authors.lastname: Reiser
authors.affiliation: Institute for Clinical Radiology, Ludwig Maximilian University Hospital, Munich, Germany.
authors.forename: D A
authors.initials: DA
authors.lastname: Clevert
mesh_terms: D000818:Animals; D002294:Carcinoma, Squamous Cell / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology; D003287:Contrast Media; D005260:Female; D007012:Hypopharyngeal Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D045423:Microbubbles; D023421:Models, Animal; D064847:Multimodal Imaging; D009368:Neoplasm Transplantation; D011923:Rats, Nude; D014463:Ultrasonography
chemical_list: D003287:Contrast Media
keywords: Image fusion; contrast-enhanced ultrasound (CEUS); experimental animal model; magnetic resonance imaging (MRI); multimodality imaging