title: Reduced-FOV excitation decreases susceptibility artifact in diffusion-weighted MRI with endorectal coil for prostate cancer detection.
abstract: The purposes of this study were to determine if image distortion is less in prostate MR apparent diffusion coefficient (ADC) maps generated from a reduced-field-of-view (rFOV) diffusion-weighted-imaging (DWI) technique than from a conventional DWI sequence (CONV), and to determine if the rFOV ADC tumor contrast is as high as or better than that of the CONV sequence. Fifty patients underwent a 3T MRI exam. CONV and rFOV (utilizing a 2D, echo-planar, rectangularly-selective RF pulse) sequences were acquired using b=600, 0s/mm(2). Distortion was visually scored 0-4 by three independent observers and quantitatively measured using the difference in rectal wall curvature between the ADC maps and T2-weighted images. Distortion scores were lower with the rFOV sequence (p<0.012, Wilcoxon Signed-Rank Test, n=50), and difference in distortion scores did not differ significantly among observers (p=0.99, Kruskal-Wallis Rank Sum Test). The difference in rectal curvature was less with rFOV ADC maps (26%±10%) than CONV ADC maps (34%±13%) (p<0.011, Student's t-test). In seventeen patients with untreated, biopsy confirmed prostate cancer, the rFOV sequence afforded significantly higher ADC tumor contrast (44.0%) than the CONV sequence (35.9%), (p<0.0012, Student's t-test). The rFOV sequence yielded significantly decreased susceptibility artifact and significantly higher contrast between tumor and healthy tissue.
authors.affiliation: Department of Radiology and Biomedical Imaging, University of California at San Francisco, San Francisco, CA, United States. Electronic address: Natalie.Korn@ucsf.edu.
authors.forename: Natalie
authors.initials: N
authors.lastname: Korn
authors.affiliation: Department of Radiology and Biomedical Imaging, University of California at San Francisco, San Francisco, CA, United States; The Graduate Group in Bioengineering, University of California at San Francisco & Berkeley, CA, United States.
authors.forename: John
authors.initials: J
authors.lastname: Kurhanewicz
authors.affiliation: General Electric Healthcare, Menlo Park, CA, United States.
authors.forename: Suchandrima
authors.initials: S
authors.lastname: Banerjee
authors.affiliation: Department of Radiology and Biomedical Imaging, University of California at San Francisco, San Francisco, CA, United States; The Graduate Group in Bioengineering, University of California at San Francisco & Berkeley, CA, United States.
authors.forename: Olga
authors.initials: O
authors.lastname: Starobinets
authors.affiliation: Department of Bioengineering, University of California at Berkeley, Berkeley, CA, United States.
authors.forename: Emine
authors.initials: E
authors.lastname: Saritas
authors.affiliation: Department of Radiology and Biomedical Imaging, University of California at San Francisco, San Francisco, CA, United States; The Graduate Group in Bioengineering, University of California at San Francisco & Berkeley, CA, United States.
authors.forename: Susan
authors.initials: S
authors.lastname: Noworolski
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001331:Automation; D001706:Biopsy; D003936:Diagnosis, Computer-Assisted; D038524:Diffusion Magnetic Resonance Imaging; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D010363:Pattern Recognition, Automated; D011446:Prospective Studies; D017430:Prostate-Specific Antigen / Q000378:metabolism; D011471:Prostatic Neoplasms / Q000175:diagnosis* / Q000473:pathology*; D012007:Rectum / Q000473:pathology; D015203:Reproducibility of Results
chemical_list: D017430:Prostate-Specific Antigen
keywords: ADC; Diffusion-weighted imaging; Endorectal; MRI; Prostate; Reduced FOV