title: [Clinical use of digital retrospective image fusion of CT, MRI, FDG-PET and SPECT -- fields of indications and results].
abstract: OBJECTIVE
  To evaluate the feasibility and the clinical benefits of retrospective digital image fusion (PET, SPECT, CT and MRI).
  
  
  METHODS
  In a prospective study, a total of 273 image fusions were performed and evaluated. The underlying image acquisitions (CT, MRI, SPECT and PET) were performed in a way appropriate for the respective clinical question and anatomical region. Image fusion was executed with a software program developed during this study. The results of the image fusion procedure were evaluated in terms of technical feasibility, clinical objective, and therapeutic impact.
  
  
  RESULTS
  The most frequent combinations of modalities were CT/PET (n = 156) and MRI/PET (n = 59), followed by MRI/SPECT (n = 28), CT/SPECT (n = 22) and CT/MRI (n = 8). The clinical questions included following regions (more than one region per case possible): neurocranium (n = 42), neck (n = 13), lung and mediastinum (n = 24), abdomen (n = 181), and pelvis (n = 65). In 92.6 % of all cases (n = 253), image fusion was technically successful. Image fusion was able to improve sensitivity and specificity of the single modality, or to add important diagnostic information. Image fusion was problematic in cases of different body positions between the two imaging modalities or different positions of mobile organs. In 37.9 % of the cases, image fusion added clinically relevant information compared to the single modality.
  
  
  CONCLUSIONS
  For clinical questions concerning liver, pancreas, rectum, neck, or neurocranium, image fusion is a reliable method suitable for routine clinical application. Organ motion still limits its feasibility and routine use in other areas (e. g., thorax).
authors.affiliation: Campus Virchow-Klinikum, Klinik für Strahlenheilkunde, Charité, Universitätsmedizin Berlin. lemke@charite.de
authors.forename: A-J
authors.initials: AJ
authors.lastname: Lemke
authors.forename: S M
authors.initials: SM
authors.lastname: Niehues
authors.forename: H
authors.initials: H
authors.lastname: Amthauer
authors.forename: T
authors.initials: T
authors.lastname: Rohlfing
authors.forename: N
authors.initials: N
authors.lastname: Hosten
authors.forename: R
authors.initials: R
authors.lastname: Felix
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D002675:Child, Preschool; D005240:Feasibility Studies; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D007089:Image Enhancement; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D049268:Positron-Emission Tomography; D011187:Posture; D011446:Prospective Studies; D019275:Radiopharmaceuticals; D012680:Sensitivity and Specificity; D012984:Software; D015899:Tomography, Emission-Computed, Single-Photon; D014057:Tomography, X-Ray Computed
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18