Like cysts in any other organ, renal cysts display three basic characteristics: they are anechoic, have a thin, well-defined capsule and exhibit posterior enhancement. It can be difficult to appreciate the posterior enhancement if the hyperechoic perirenal fat lies distal to the cyst; scanning from a different angle (Fig. below) may be helpful. Haemor-rhage or infection can give rise to low-level echoes within a cyst and in some cases the capsule may display calcification. Whilst a solitary, simple cyst can almost certainly be ignored, cysts with more complex acoustic characteristics may require further investigation,
Ultrasound images Small renal cyst containing calcification following episodes of infection. This remained stable on follow-up.
Ultrasound images Simple renal cyst with posterior enhancement (arrowheads).
LiveJournal Tags: Simple renal cyst with posterior enhancement (arrowheads).