Allium<sup>TM</sup> Bulbar Urethral Stent: An Updated Long-Term Multi-Center Study with New Treatment Modality for Bulbar Urethral Stricture

Abstract

Objectives: To report the 2-years follow-up of patients with bulbar urethral strictures treated with the new Allium TM Bulbar Urethral Stent (Allium BUS). Methods: The stent is a fully covered, selfexpendable, large caliber metal stent specially designed for the treatment of bulbar urethral strictures. The stent is comprised of a coiled super-elastic structure covered by a polymeric coating designed to prevent mucosal hyperplasia. The indwelling time is 12 months, after which the stent should have been removed. Sixty-four patients with recurrent bulbar stricture were treated with Allium BUS in 3 worldwide centers. Results: All stents were successfully inserted with no peri-operative complications. In a median follow-up of 25.5 months, the mean maximal flow rate following stent insertion was significantly higher compared to the pre-surgical flow rate (14 ml/sec vs 6.6 ml/sec, p < 0.0001). Longer indwelling time and shorter stricture length were significantly related to success rate. The main complications were stent migration, stent re-stenosis and urinary tract infections. Conclusions: The temporary placement of the Allium TM BUS showed encouraging results with long-term failure rate of only 25%.

Management of Recurrent Urethral Strictures: A Therapeutic Challenge

“…Literature also suggests iatrogenic etiology accounting for more than 45% of stricture cases, especially in patients older than 45 years old. Iatrogenic causes include transurethral resection (TUR), cystoscopy, brachytherapy, hypospadias surgery, and urethral catheterization [ 6 ].…”

“…A negative perception of permanent stenting is its permanent placement in the urethra. Temporary urethral stenting, however, following urethral dilation or internal urethrotomy has been found to maintain urethral patency and decrease stricture recurrence, clearly without the need for permanent implantation [ 6 ]. The literature review also suggests the use of temporary urethral stent placement for recurrent bulbar urethral strictures after direct visual internal urethrotomy or dilatation as an option before deciding on urethroplasty [ 7 ].…”

Initial experience with Allium™ stent in the management of bulbar urethral stricture

“…It is a second generation stent composed of a nitinol metal coil with a polymer coating. The coating is designed to prevent epithelialisation and mucosal hyperplasia post urethrotomy, thereby maintaining patency and reducing stricture recurrence ( 12 ). The stents are produced in three lengths, 50, 60, and 80 mm, all of which are 45 French in calibre.…”

Allium Stents: A Novel Solution for the Management of Upper and Lower Urinary Tract Strictures

“…We reported a significant increase in urinary peak flow and significant decrease in International Prostate Symptom score (IPSS); both improved immediately and were also maintained in the long-term follow-up. 3 …”

“…Sixteen patients (25%) had undergone an early stent removal because of: migration (6 patients), progressive deterioration of urinary peak flow (6 patients), and chronic urinary tract infection (UTI) (4 patients). 3 …”