Image quality and cancer visibility of T2-weighted magnetic resonance imaging of the prostate at 7 Tesla

Eur Radiol. 2014 Aug;24(8):1950-8. doi: 10.1007/s00330-014-3234-6. Epub 2014 May 28.

Abstract

Objectives: To assess the image quality of T2-weighted (T2w) magnetic resonance imaging of the prostate and the visibility of prostate cancer at 7 Tesla (T).

Materials & methods: Seventeen prostate cancer patients underwent T2w imaging at 7T with only an external transmit/receive array coil. Three radiologists independently scored images for image quality, visibility of anatomical structures, and presence of artefacts. Krippendorff's alpha and weighted kappa statistics were used to assess inter-observer agreement. Visibility of prostate cancer lesions was assessed by directly linking the T2w images to the confirmed location of prostate cancer on histopathology.

Results: T2w imaging at 7T was achievable with 'satisfactory' (3/5) to 'good' (4/5) quality. Visibility of anatomical structures was predominantly scored as 'satisfactory' (3/5) and 'good' (4/5). If artefacts were present, they were mostly motion artefacts and, to a lesser extent, aliasing artefacts and noise. Krippendorff's analysis revealed an α = 0.44 between three readers for the overall image quality scores. Clinically significant cancer lesions in both peripheral zone and transition zone were visible at 7T.

Conclusion: T2w imaging with satisfactory to good quality can be routinely acquired, and cancer lesions were visible in patients with prostate cancer at 7T using only an external transmit/receive body array coil.

Key points: • Satisfactory to good T2-weighted image quality of the prostate is achievable at 7T. • Periprostatic lipids appear hypo-intense compared to healthy peripheral zone tissue at 7T. • Prostate cancer is visible on T2-weighted MRI at 7T.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Artifacts*
  • Humans
  • Image Enhancement*
  • Magnetic Resonance Imaging / methods*
  • Male
  • Middle Aged
  • Neoplasm Staging / methods*
  • Prostate / pathology*
  • Prostatic Neoplasms / diagnosis*
  • Reproducibility of Results