title: Characterization and therapy monitoring of head and neck carcinomas using diffusion-imaging-based intravoxel incoherent motion parameters-preliminary results.
abstract: BACKGROUND
  Using the intravoxel incoherent motion (IVIM) model, diffusion-related coefficient (D) and perfusion-related parameter (f) can be measured. Here, we used IVIM imaging to characterize squamous cell carcinomas of head and neck (HNSCC) and evaluated its application in follow-up after nonsurgical organ preserving therapy.
  
  
  METHODS
  Twenty-two patients with locally advanced HNSCC (clinical stage III to IVb) were examined before treatment using eight different b values (b = 0, 50, 100, 150, 200, 250, 700, 800 s/mm(2)). All patients were followed for at least 7.5 months after conclusion of therapy. In 16 of these patients, follow-up MRI was available. Using the IVIM approach, f and D were extracted using a bi-exponential fit. For comparison, ADC maps were calculated.
  
  
  RESULTS
  The initial values of f before therapy were located between 5.9 % and 12.9 % (mean: 9.4 ± 2.4 %) except for two outliers (f = 17.9 % and 18.2 %). These two patients exclusively displayed poor initial treatment response. Overall, high initial f (13.1 ± 4.1 % vs. 9.1 ± 2.4 %) and ADC (1.17 ± 0.08 × 10(-3) mm(2)/s vs. 0.98 ± 0.19 × 10(-3) mm(2)/s) were associated with poor short term outcome (n = 6) after 7.5 months follow-up. D values before treatment were 0.98 × 10(-3) ± 0.18 mm(2)/s and ADC values were 1.03 × 10(-3) ± 0.18 mm(2)/s. At follow-up, in all primary responders, D (69 ± 52 %), f (65 ± 46 %), and ADC (68 ± 49%) increased.
  
  
  CONCLUSIONS
  Our preliminary evaluation indicates that an initial high f may predict poor prognosis in HNSCC. In responders, a significant increase of all IVIM parameters after therapy was demonstrated.
authors: Department of Radiology E010, German Cancer Research Center, Heidelberg, Germany. t.hauser@dkfz.de
authors: Thomas
authors: T
authors: Hauser
authors: Marco
authors: M
authors: Essig
authors: Alexandra
authors: A
authors: Jensen
authors: Lars
authors: L
authors: Gerigk
authors: Frederik Bernd
authors: FB
authors: Laun
authors: Marc
authors: M
authors: Münter
authors: Dirk
authors: D
authors: Simon
authors: Bram
authors: B
authors: Stieltjes
mesh_terms: D000328:Adult; D000368:Aged; D002294:Carcinoma, Squamous Cell / Q000175:diagnosis* / Q000473:pathology*; D059248:Chemoradiotherapy / Q000379:methods*; D038524:Diffusion Magnetic Resonance Imaging / Q000379:methods*; D005260:Female; D006258:Head and Neck Neoplasms / Q000175:diagnosis* / Q000473:pathology*; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009038:Motion; D059351:Organ Sparing Treatments / Q000379:methods*; D010865:Pilot Projects; D011379:Prognosis; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D000077195:Squamous Cell Carcinoma of Head and Neck; D016896:Treatment Outcome; D047368:Tumor Burden / Q000187:drug effects