[Improved tumor stent for internal palliative urinary diversion]. / Neu entwickelter Tumorstent zur internisierten palliativen Harnableitung.

The disadvantages of high flexible endoureteral stents (DJ) in case of tumorinduced extrinsic ureteral compression are due to an insufficient vertical stability of the used stents leading to stent-compression and consecutive hydro- or pyonephrosis. The new developed tumor-stent used in case of tumor-induced ureteral compression is available from 6 to 8 French in diameter and 24 to 32 cm in length. The corpus consists of a combination of high-stability plastics but is of sufficient elasticity in length. Both ends consist of extremely elastic J-parts guaranteeing an exact fixation. As against common DJ's with the same outside-diameter the new stent has a comparable interior diameter and compared to used "old" tumor stents promises a higher interior flow in case of extrinsic diseases. The application can be undertaken in well-known technique, needs no special instrumentation and no learning-curve. To date 52 stents at our urologic departments were placed without any problems, the latest remaining for 15 months. Tumor-induced compression or a higher rate of encrustation could not be seen. All patients tolerated these stents well. In our opinion the new stabilized endoureteral stent can be seen as a better solution instead of percutaneous nephrostomy or frequent stent changing in patients with tumor induced extrinsic ureteral compression.

Behavior of different suture materials in the urinary bladder of the rabbit with special reference to wound healing, epithelization and crystallization.

Five urinary bladder incisions were performed in 16 rabbits and the defects closed by plain catgut 4-0, chromic catgut 4-0, polypropylene 4-0, polyglactin 910 4-0 and polyglactin 910 8-0 in the form of an all-layer suture, thereby obtaining a total of 80 suture sites. The running sutures in 8 animals were reviewed by light microscopy after 1, 2, 7 and 15 weeks, and in 8 additional animals after 3 days, 1, 2, 7 and 15 weeks by scanning electron microscopy. Moreover, we analyzed and compared the autopsy findings on gross inspection, the urinary sediments and urinary cultures of the individual animals. Scanning electron-microscopic evaluations showed that epithelization of the intraluminal suture portions can be accomplished after 3 days already. Reduced suture strength and rapid absorption of the suture material prevent later postoperative incrustations. Light-microscopic inspection of the segments of the bladder wall bearing this suture material suggests that a minor inflammatory tissue response around the suture material--with polyglactin 910 8-0 in particular--is more likely to enhance regeneration of the tunica muscularis and to prevent formation of cysts than seen with a long-standing highly inflammatory tissue response around the suture site of catgut threads. In the animal experiment, the polyglactin 910 suture has shown sufficient firmness and proved to be superior to any other suture material as regards the reaction to foreign bodies and inclination to incrustation.(ABSTRACT TRUNCATED AT 250 WORDS)