The intravenous urogram (IVU) remains a useful investigation in the assessment of upper urinary tract calculi. Helical computed tomography scanning appears to have superseded the IVU in the diagnosis of acute flank pain due to a higher sensitivity in diagnosis. Results of extracorporeal shockwave lithotripsy (ESWL) for lower calyceal stones are generally disappointing. Recent studies using the intravenous urogram have demonstrated that an acute infundibulopelvic angle may be a significant indicator of the likelihood of failure of ESWL. A prospective evaluation of the role of spatial anatomy in the clearance of lower calyceal stones by ESWL is needed. In future this parameter may be used to determine treatment protocols for lower calyceal stones. Future imaging methods may make the IVU redundant, but for the time being it remains an essential part of the urologist's armamentarium.
Scottish Lithotriptor Centre, Western General Hospital, Edinburgh, UK
Correspondence to: Mr David Tolley, Director, Scottish Lithotriptor Centre, Western General Hospital, Crewe Road, Edinburgh, EH4 2XU, UK