3-DIMENSIONAL CT-SCAN RECONSTRUCTION OF RENAL CALCULI - A NEW TOOL FOR MAPPING-OUT STAGHORN CALCULI AND FOLLOW-UP OF RADIOLUCENT STONES

Objectives: The development of CT scanners (CT scan) with continuous r apid spiral acquisition now allows three-dimensional reconstructions o f mobile organs such as kidneys. The aim of this study was to apprecia te the merits of this new technique in the field of renal lithiasis. M ethod: This non-invasive technique was applied in 27 renal calculi (23 staghorn and 4 radiolucent stones). The acquisition does not require any injection of contrast material. Reconstruction was carried out by three-dimensional (3D) shaded surface display. Results: 3D reconstruct ion of calculi permits a precise study of the shape of the stone, and of the number, size and direction of its branches. Therefore, it allow s for better planning of the PCNL (number of ports, peroperative pelvi -caliceal exploration ...). Large radiolucent calculi are clearly defi ned with 3DS, facilitating the follow-up under medical treatment. Conc lusion: 3D CT scan reconstruction is a noninvasive, cost-effective met hod which offers high quality 3D images of renal calculi. These result s should spur the more widespread use of this technique.