title: Feasibility of CAIPIRINHA-Dixon-TWIST-VIBE for dynamic contrast-enhanced MRI of the prostate.
abstract: OBJECTIVE
  To evaluate the feasibility of a CAIPIRINHA-Dixon-TWIST (CDT)-VIBE sequence for improving image quality and temporal resolution in dynamic contrast-enhanced MRI (DCE-MRI) of the prostate.
  
  
  METHODS
  44 male patients (age 63.9 ± 8.9 years) with clinically suspected prostate cancer underwent DCE-MRI at a 3T MRI scanner (Magnetom Skyra, Siemens Healthcare, Erlangen, Germany) using a CDT-VIBE sequence (spatial resolution=3×1.2×1.2mm(3), temporal resolution=5s, total scan duration=4:10 min) with body-weight-adapted administration of contrast agent (Gadobutrol, Bayer Healthcare, Berlin, Germany). To investigate effects on image quality, the same sequence was acquired three times per patient during the late phase: 1. with the same protocol as in the arterial phase (VS5), 2. without view-sharing (no view-sharing, NVS) using a 2-fold CAIPIRINHA acceleration R=2 (temporal resolution=15s, NVS15) and 3. NVS using a 6-fold CAIPIRINHA acceleration R=6 (temporal resolution=5s, NVS5). SNR and CNR were evaluated with the subtraction method. Image quality of the three sequences (VS5, NVS15, NVS5) was subjectively assessed by 2 blinded radiologists using a 5-point Likert scale (5 being excellent). Perfusion profiles of visually normal prostate and of malignant lesions as characterized by Wash-In, Wash-Out, time-to-peak (TTP) and initial area under the curve (iAUC) from the original datasets (temporal resolution=5s) and from datasets with a downsampled temporal resolution (15s) were compared.
  
  
  RESULTS
  In 20 of 44 included patients, potentially malignant lesions were identified in which 16 had histologically confirmed prostate cancer. SNR was highest for VS5 and NVS15, and lowest for NVS5 (p <.001). Concordantly, subjective image quality was comparable for VS5 and NVS15 (sum score 23.20 ± 1.03 vs 23.53 ± 1.34) and significantly lower for NVS5 (sum score 9.83 ± 2.32; p<.001). Perfusion parameters of macroscopically normal prostate tissue and suspect lesions differed significantly between original datasets and datasets with simulated lower temporal resolution, with the latter showing higher Wash-In (p=.002), lower Wash-Out (p=.003), higher Time-to-Peak (p<.001) and lower iAUC (p<.001).
  
  
  CONCLUSIONS
  CDT-VIBE can be readily exploited for DCE-MRI of the prostate preserving the diagnostic image quality while providing high temporal resolution for quantitative diagnostic assessment of enhancement curves in malignant lesions.
authors: Department of Diagnostic and Interventional Radiology, Eberhard Karls University Tuebingen, University Hospital Tuebingen, 72076 Tuebingen, Germany. Electronic address: ahmed.othman@uni-tuebingen.de.
authors: Ahmed E
authors: AE
authors: Othman
authors: Department of Diagnostic and Interventional Radiology, Eberhard Karls University Tuebingen, University Hospital Tuebingen, 72076 Tuebingen, Germany.
authors: Petros
authors: P
authors: Martirosian
authors: Department of Diagnostic and Interventional Radiology, Eberhard Karls University Tuebingen, University Hospital Tuebingen, 72076 Tuebingen, Germany.
authors: Christina
authors: C
authors: Schraml
authors: Department of Diagnostic and Interventional Radiology, Eberhard Karls University Tuebingen, University Hospital Tuebingen, 72076 Tuebingen, Germany.
authors: Jana
authors: J
authors: Taron
authors: Department of Diagnostic and Interventional Radiology, Eberhard Karls University Tuebingen, University Hospital Tuebingen, 72076 Tuebingen, Germany.
authors: Jakob
authors: J
authors: Weiss
authors: Department of Diagnostic and Interventional Radiology, Eberhard Karls University Tuebingen, University Hospital Tuebingen, 72076 Tuebingen, Germany.
authors: Georg
authors: G
authors: Bier
authors: Department of Urology, Eberhard Karls University Tuebingen, University Hospital Tuebingen, 72076 Tuebingen, Germany.
authors: Christian
authors: C
authors: Schwentner
authors: Siemens Healthcare GmbH, Erlangen, Germany.
authors: Dominik
authors: D
authors: Nickel
authors: Department of Diagnostic and Interventional Radiology, Eberhard Karls University Tuebingen, University Hospital Tuebingen, 72076 Tuebingen, Germany.
authors: Fabian
authors: F
authors: Bamberg
authors: Department of Diagnostic and Interventional Radiology, Eberhard Karls University Tuebingen, University Hospital Tuebingen, 72076 Tuebingen, Germany.
authors: Ulrich
authors: U
authors: Kramer
authors: Department of Diagnostic and Interventional Radiology, Eberhard Karls University Tuebingen, University Hospital Tuebingen, 72076 Tuebingen, Germany.
authors: Konstantin
authors: K
authors: Nikolaou
authors: Department of Diagnostic and Interventional Radiology, Eberhard Karls University Tuebingen, University Hospital Tuebingen, 72076 Tuebingen, Germany.
authors: Mike
authors: M
authors: Notohamiprodjo
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D003287:Contrast Media; D005240:Feasibility Studies; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D009942:Organometallic Compounds; D011467:Prostate / Q000473:pathology; D011471:Prostatic Neoplasms / Q000473:pathology*; D015203:Reproducibility of Results
chemical_list: D003287:Contrast Media; D009942:Organometallic Compounds; C090600:gadobutrol
keywords: CDT-VIBE; DCE-MRI; Dynamic imaging; Magnetic resonance imaging; Prostate; Prostate cancer