Treating bladder-outflow obstruction with thermo-expandable prostate metal stents

Thermoexpandable Urethral Nickel-Titanium Stent Memokath for Managing Urethral Bulbar Stricture After Failed Urethroplasty

Introduction: Urethral stenting became popular two decades ago, but nowadays its frequency is slightly decreased because of the rising application of urethroplasty. Today urethral stenting is reserved only for failure after urethral reconstruction or in cases when the plastic surgery is unfavorable. The Memokath stent (Pnn Medical A/S, Kvistgaard, Denmark) is manufactured from a biocompatible alloy of nickel and titanium and known to be the most popular in this field. Case Description: A 38-year-old man with a history of 9 years Memokath urethral stenting was admitted to our clinic with obstructive lower urinary tract symptoms. The indication for Memokath stenting was repeated recurrences after endoscopic and reconstructive operations. The plain radiography showed a normal position of the stent and only the endoscopic examination revealed its total calcification. New superpulse thulium fiber laser has been used to free the stent from the stones and safely remove it without additional urethral injury. Results: The postoperative time was within normal limits, the catheter was removed on the fourth day after operation. Three months follow-up was without stricture recurrence. We continue active surveillance of the patient. Conclusion: The calcification of the stent could be properly diagnosed endoscopically; the Memokath stent could be safely removed in 9 years after implantation; thulium fiber laser is effective and safe in the management of encrusted urethral stent.

The stone formation in the Memotherm urethral stent implantation area: Is it a rare complication?

Recurrent urethral stricture is one of the biggest problems in urology. Urethral stents as an alternative treatment has been used since 1985. The stone formation in the Memotherm (Angiomed) urethral stent implantation area is a rare complication. We report the case of a 67-year-old man who had a stone in the Memotherm urethral stent implantation area 6 years after his urethral stent surgery.

New biodegradable drug-eluting stents for urethral strictures in a rabbit model

In this study, the feasibility and the effect of a new biodegradable drug-eluting urethral stents for the treatment of urethral stricture in a rabbit model were evaluated, and the biocompatibility properties of the new biodegradable drug-eluting urethral stents in the rabbit urethral assessed. A total of 34 male New Zealand White rabbits with urethral strictures were used, and equally divided into two groups: with drug stents and drug-free stents. The urethral strictures were made by using a self-control explosion device as the control. Stents were surgically implanted into the stenotic urethras of rabbits under direct vision. Reparative effects, including biocompatibility assessment, were evaluated by urethroscopy, retrograde urethrography, and histology at different intervals at weeks 4, 8, and 12. Although retrograde urethrography and urodynamic results at 12 weeks showed no comparable differences among the three groups, urethroscopic and histological follow-up indicated that the drug stents had minimized the stent-related inflammatory responses, urothelial hyperplasia, and scar formation compared with the drug-free stents. The new biodegradable paclitaxel-eluting stents were more biocompatible and effective for treating urethral strictures in the rabbit model than the drug-free stents.