Table 3 Image quality (IQ) assessed by two independent observers on axial T2WI and DWI/ADC for both combined rigid phased-array endorectal coil and an external phased-array coil (ERC-PAC) and PAC acquisitions

Image sharpness/structure detail

 ◦ Definition: Clear depiction of prostate edge or degree of blurring, clarity of border delineation, peripheral-transition zone boundary, and the extent of lesion definition and internal morphologic features

 ◦ Scores: 1, non-diagnostic; 2, poor; 3, satisfactory; 4, good; and 5, excellent sharpness/detail.

Motion artifact

 ◦ Definition: Presence and severity of image blurring due to patient motion

 ◦ Scores: 1, non-diagnostic; 2, severe; 3, moderate; 4, mild; and 5, motion free

Anatomic distortion

 ◦ Definition: Distortion in size, profile, or orientation of the prostate using T2W as a reference

 ◦ Scores: 1, non-diagnostic; 2, severe; 3, moderate; 4, mild; and 5, no distortion

Ghosting/susceptibility artifacts

 ◦ Definition: Displaced reduplications of image or structure that propagate in phase encoding direction

 ◦ Scores: 1, non-diagnostic; 2, severe; 3, moderate; 4, mild; and 5, no ghosting/susceptibility

Coil related phase artifacts

 ◦ Definition: Displaced reduplications of the endorectal coil that propagate in phase encoding direction

 ◦ Scores: 1, non-diagnostic; 2, severe; 3, moderate; 4, mild; and 5, no coil artifact

Overall image quality

 ◦ Scores: 1, non-diagnostic; 2, poor; 3, satisfactory; 4, good; and 5, excellent image quality