Figure 2b. Use of MR imaging to evaluate the relative enhancement of a hyperattenuating and high-signal-intensity cyst in a 53-year-old asymptomatic man. CT demonstrated a 3-cm-diameter hyperattenuating (40 HU) lesion in the left kidney. (a-c) Serial precontrast (a), corticomedullary phase (b), and nephrographic phase (c) T1-weighted breath-hold gradient-echo MR images show no significant enhancement of the lesion, with relative signal intensities of 138, 138, and 139, respectively. (d) Longitudinal sonogram also shows that the mass is cystic.