A Novel Thermo-Expandable Ureteral Metal Stent for the Minimally Invasive Management of Ureteral Strictures

Abstract

Purpose:

We assess the safety, efficacy, and cost of the novel long-term indwelling thermo-expandable Memokath ureteral stent for the management of malignant and benign ureteral strictures.

Materials and Methods:

Since October 2004, we treated 73 patients (34 men), ages 23 to 84 years (mean 57.7) with 86 ureteral strictures (13 bilateral) with the Memokath^™ 051 stent. The causes of the strictures were benign in 55 cases and malignant in 31 cases. Follow-up included radiography, renal ultrasonography, and renography if needed after 2 weeks, 3 months, and then every 6 months.

Results:

The mean operative time was 23 minutes, while the mean hospital stay was 1.5 days. The average indwelling time of an individual Memokath was 11.2 months. After a mean follow-up period of 17.1 months, there were 68 stents in situ. In 12 cases, spontaneous resolution of the ureteral stricture was revealed after a mean indwelling time of 9 months. The remainding six cases were treatment failures. In 15 cases, because of late complications, a Memokath exchange took place after a mean period of 18 months. A total of 26 complications were revealed after the insertion of 102 Memokath stents. These included six cases of urinary tract infections; 15 stent manipulations were needed because of stent dislodgement, and 5 stents were removed because of encrustration and blockage. In the long term, the overall costs for the Memokath treatment and follow-up were considerably less than with the conventional Double-J stent.

Conclusions:

The ureteral Memokath stent is a promising, safe, and efficient treatment option for the minimally invasive management of both benign and malignant ureteral strictures.

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