Linear ultrasound assessment of the pyramid and medulla in the paediatric kidney.

Abstract

Introduction: The renal pyramid and medulla within the paediatric kidney are vulnerable to many pathological changes due to their distinctive arrangement of blood supply and hypertonic environment. It is thus important for paediatric sonographers to be well oriented to identify unusual corticomedullary architecture and altered patterns of echogenicity that may be suggestive of an underlying abnormality. These ultrasound patterns are best demonstrated with the use of a high frequency linear transducer and a well-optimised, diligent technique to identify subtle changes. The aim of this presentation is to review normal ultrasound appearances of the paediatric kidney when investigated with a linear transducer and highlight the alterations often seen in the presence of an underlying abnormality. Method(s): An extensive literature review was performed to compare and contrast sonographic appearances of the normal and abnormal paediatric kidney, with a particular focus on the pathological changes affecting the renal medulla and pyramids. Result(s): With the use of a linear transducer, the renal interstitium, subtle increases in medullary echogenicity, structural changes to the collecting ducts, and deposition of calcifications are credibly illustrated on ultrasound. Conclusion(s): Assessment of the renal pyramid and medulla with a linear transducer are essential in a paediatric renal ultrasound examination. Subtle changes in echogenicity as well as alterations to the normal corticomedullary architecture are abnormalities that may not be appreciated if the kidney was assessed only with a curvilinear transducer. Take home message: Perform a high quality focussed linear examination of the paediatric kidney for each examination.