Angiography and interventional radiology of the kidneys

For imaging of renal pathology a broad spectrum of radiologic diagnostic pr ocedures are available which are, sometimes and particularly more recently, competing among each other in their diagnostic yield and relevance. For tu morous lesions ultrasound, computed tomography and magnetic resonance imagi ng are performed predominantly. Angiography is no longer required with the exception of highly selected cases and in some specific preoperative workup requirements. Until recently, catheter based digital subtraction angiograp hy has been considered as gold standard. However, non-invasive techniques s uch as CT-angiography and MR-angiography are evolving parallel to their qua ntum leap of resolutions and readiness to use. Nevertheless, well accepted criteria for quality assessement of these new modalities are still lacking. More comparison studies are urgently warranted. Despite the availability o f ultrashort pulse sequences applying the T1 relaxation reduction effect of gadolinium enhanced MR techniques overestimation of renal artery stenosis still poses a substantial problem. Renal intervention implies a variety of procedures such as plain angioplasty, stent placement, embolization of trau matic and both benign and malignant tumors. These methods have emerged over the last two decades from a more experimental nature to a fully accepted t reatment option. When renal artery angioplasty is embedded in an aggressive approach including stenting as an adjunct for more complex cases, renal os tial lesions and a well organized follow-up regimen its therapeutic potenti al for treatment of renal insufficiency, malignant hypertension,for organ p reservation bears a very high potential. Provided adequat periinterventiona l drug regimen restenosis rates may be as low as 10%. In highly selected ca ses capillary embolization might be used as an alternative to nephrectomy w ith a similar clinical outcome. Particularly the development of superselect ive small caliber embolization catheters parallel to further refinement of embolization material has aided to use superselective occlusion techniques in benign vascular lesions and renal trauma.