Memokath Stent Failure in Recurrent Bulbar Urethral Strictures: Results From an Investigative Pilot Stage 2A Study

Abstract

Objective: To evaluate the efficacy of the Memokath stent in managing recurrent bulbar urethral strictures.

Materials and methods: This is an investigative pilot stage 2A study in patients with a recurrent bulbar urethral stricture who underwent a Memokath stent implant from January 2014 to January 2016 in a single high-volume center for urethral reconstruction. The Memokath stent (Pnn Medical A/S, Kvistgaard, Denmark) was manufactured from nitinol, a biocompatible alloy of nickel and titanium, which was endoscopically placed. It had a 24-Fr outside diameter and was preloaded on a disposable delivery device. When correctly positioned, the stent was anchored by a warm water (55°C) instillation, which expanded the proximal end of the stent from 24 to 42 Fr .The stent was provided in lengths of 3-7 cm in 1-cm increments.

Results: Sixteen patients were included in the study. The median follow-up was 16 months. In 7 patients (43.7%), the stent was removed within 1 year. The main adverse events were pain, encrustations, stones, and recurrent strictures. Four patients (25%) were considered a success and 12 (75%) were failures. Study limitations include the small sample.

Conclusion: The Memokath stent was deemed to be not clinically helpful and had significant side effects, and therefore should not be considered a treatment option for men with bulbar urethral strictures.