[Imaging of the kidney and the urinary tract]. / Bildgebung der Nieren und Harnwege.

Radiologic imaging is very important for urologic diagnostics. Acute flank pain is frequently caused by an obstructive ureteral stone which is diagnosed by native computed tomography (CT) or alternatively by intravenous urography (IVU). In suspicion of a parenchymal renal tumor a CT is performed. Tumors of the renal pelvis or the ureter are diagnosed by IVU followed by a retrograde pyelography to achieve a selective local wash-cytology. A CT or MRI of the abdomen are necessary for staging (local lymphnodes or systemic metastasis?) and to show also the local tumor extension. Exophytic and invasive processes of the bladder can be seen by CT or by ultrasound, but if a bladder tumor is suspected a cystoscopy is mandatory as primary diagnostic tool and can't be replaced by any imaging modalities. Cystography shows bladder injuries and serves together with a voiding image to identify vesicoureteral reflux. In strictures and injuries of the urethra a retro- and antegrade urethrography should be performed.

Extracorporeal shock wave lithotripsy of lower calyx calculi: how much is treatment outcome influenced by the anatomy of the collecting system?

OBJECTIVES: Extracorporeal shock wave lithotripsy (ESWL) of lower calyx stones has been criticized because of the high incidence of residual fragments. Controversial results have been reported regarding the stone-free rate after ESWL depending on the influence of the collecting system anatomy on stone clearance. Therefore we evaluated our stone-free rate after ESWL of lower calyx stones and searched for correlations to various anatomic parameters of the collecting system. METHODS: Ninety-six patients with isolated lower calyx stones treated exclusively with ESWL (Dornier HM3) were evaluated 3 mo postoperatively. The results were correlated with the following anatomic parameters of the collecting system as determined from the pretreatment intravenous urography: (1) lower infundibulum width, (2) lower infundibulum length, (3) infundibulopelvic angle, (4) volume of the collecting system. Follow-ups were performed 24 h after ESWL with an abdominal plain film and 3 mo postoperatively with a urography or abdominal plain X-ray together with renal ultrasound. RESULTS: Three months postoperatively, 68% of all patients were stone free, including 69% of the patients with stones initially < or =1 cm, and 67% of the patients with stones >1 cm. Stone-free patients compared with patients having residual fragments had no significant differences in infundibulum width, infundibulum length, infundibulopelvic angle, or collecting system volume. CONCLUSIONS: A stone-free rate 3 mo after ESWL of 68% overall justifies ESWL as a possible treatment option for lower calyx stones. Influence of the collecting system anatomy on disintegrate clearance from the lower calyx could not be demonstrated.