[Diagnostic methods for obstruction of the upper urinary tract: which tests are available in 2001]

The presence of upper urinary tract obstruction, its site and its nature can be determined and the most appropriate treatment can be defined in the majority of clinical cases. However, in some circumstances, non-invasive or minimally invasive methods, such as ultrasonography, intravenous urography, urography with diuretic test, conventional and diuretic nephrography and MR urography, are unable to confirm the presence of obstruction, requiring assessment of the upper urinary tract by antegrade pyelomanometry. This investigation measures the pressure in the upper urinary tract perfused at a constant rate by a percutaneous catheter and allows evaluation of the obstruction. The authors discuss the place of the various upper urinary tract investigations to confirm the definitive diagnosis of upper urinary tract obstruction.