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

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.