A 6-year retrospective cost-effectiveness analysis of Memokath ureteric stents vs double-J stents – single-centre assessment

1086 THERMO EXPANDABLE SEGMENTAL METAL URETERIC STENTS IN THE MANAGEMENT OF URETERIC STRICTURES: A SINGLE CENTRE EXPERIENCE FROM THE UK

Metal Ureteral Stent for Benign and Malignant Ureteral Obstruction

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

Intraureteral metallic endoprosthesis in the treatment of ureteral strictures

New Combined Approach in Metallic Ureteral Stenting to Avoid Urothelial Hyperplasia: Study in Swine Model

NICKEL-TITANIUM SHAPE MEMORY ALLOY MEMOKATH 051 URETERAL STENT FOR MANAGING LONG-TERM URETERAL OBSTRUCTION: 4-YEAR EXPERIENCE

Analysis of Ureteral Stent Compression Force and its Role in Malignant Obstruction

Facilitation of Difficult Percutaneous Ureteral Stent Insertion

Enteral stents: from esophagus to colon

We describe our initial experience with a new metallic ureteric stent which has been designed to provide long-term urinary drainage in patients with malignant ureteric strictures. The aim is to achieve longer primary patency rates than conventional polyurethane ureteric stents, where encrustation and compression by malignant masses limit primary patency. The Resonance metallic double-pigtail ureteric stent (Cook, Ireland) is constructed from coiled wire spirals of a corrosion-resistant alloy designed to minimize tissue in-growth and resist encrustation, and the manufacturer recommends interval stent change at 12 months. Seventeen Resonance stents were inserted via an antegrade approach into 15 patients between December 2004 and March 2006. The causes of ureteric obstruction were malignancies of the bladder (n = 4), colon (n = 3), gynecologic (n = 5), and others (n = 3). One patient had the stent changed after 12 months, and 3 patients had their stents changed at 6 months. These stents were draining adequately with minimal encrustation. Four patients are still alive with functioning stents in situ for 2-10 months. Seven patients died with functioning stents in place (follow-up periods of 1 week to 8 months). Three stents failed from the outset due to bulky pelvic malignancy resulting in high intravesical pressure, as occurs with conventional plastic stents. Our initial experience with the Resonance metallic ureteric stent indicates that it may provide adequate long-term urinary drainage (up to 12 months) in patients with malignant ureteric obstruction but without significantly bulky pelvic disease. This obviates the need for regular stent changes and would offer significant benefit for these patients with limited life expectancy.

Extrinsic malignant compression of the ureter is not uncommon, often refractory to decompression with conventional polymeric ureteral stents, and frequently associated with limited survival. Alternative options for decompression include tandem ureteral stents, metallic stents and metal-mesh stents, though the preferred method remains controversial. We reviewed and updated our outcomes with tandem ureteral stents for malignant ureteral obstruction, and carried out a PubMed search using the terms "malignant ureteral obstruction," "tandem ureteral stents," "ipsilateral ureteral stents," "metal ureteral stent," "resonance stent," "silhouette stent" and "metal mesh stent." A comprehensive review of the literature and summary of outcomes is provided. The majority of studies encountered were retrospective with small sample sizes. The evidence is most robust for metal stents, whereas only limited data exists for tandem or metal-mesh stents. Metal and metal-mesh stents are considerably more expensive than tandem stenting, but the potential for less frequent stent exchanges makes them possibly cost-effective over time. Urinary tract infections have been associated with all stent types. A wide range of failure rates has been published for all types of stents, limiting direct comparison. Metal and metal-mesh stents show a high incidence of stent colic, migration and encrustation, whereas tandem stents appear to produce symptoms equivalent to single stents. Comparison is difficult given the limited evidence and heterogeneity of patients with malignant ureteral obstruction. It is clear that prospective, randomized studies are necessary to effectively scrutinize conventional, tandem, metallic ureteral and metal-mesh stents for their use in malignant ureteral obstruction.

No. 303: Percutaneous Retrograde Transjejunal Cholangiography and Biliary intervention for Beningn and Malignant Strictures

Objective To analyze the factors influencing the prognosis of benign ureteral stricture which treated by retrograde balloon dilatation in ureteroscopy. Methods Forty patients with benign unilateral ureteral stricture who underwent retrograde ureteral balloon dilatation from October 2012 to October 2016 in our department were retrospectively reviewed. Age ranged from 25 to 76 years old. Twelve cases whose ureter stenosis located at the junction of the renal pelvis, 8 cases at the upper ureter, 3 cases at the middle and 17 cases at the lower part. The length of the ureteral stricture was between 0.2 cm and 2 cm. All patients were treated with U30 ureteroscopic balloon dilation catheter, and double J stent or hippocampus ureteral stent was implanted for 6 months to 1 year after operation. The stent was replaced every 3 months and all patients were followed up for one year postoperatively. Result The operation time was between 45-90 min, with an average of 60 min. Patients spent an average of 2.5 days in the hospital after operation. There was no severe complication occurred, and the most common type of complications were hematuria and urinary tract irritation. During one year postoperative follow up, 25 patients (62.5%) were successfully treated with ureteral stricture and 15 cases (37.5%) of treatment failure were observed. Univariate Chi-square test and multivariate logistic regression analysis showed that length of ureteral stricture and degree of hydronephrosis were the main factors affecting the prognosis of surgery (P 0.05). Conclusion Ureteroscopic balloon dilatation isa safe and effective surgical treatment for benign ureteral stricture. Key words: Ureteral stenosis; Balloon dilation; Multivariate Logistic regression analysis

This study was decided to evaluate the impact of diameter and the existences of multiple side holes along the straight portion of double-J ureteral stents (DJUS) on early dysfunction of stents placed for malignant ureteral strictures. Between April 2007 and December 2011, 141 DJUSs were placed via a percutaneous nephrostomy (PCN) tract in 110 consecutive patients with malignant ureteral strictures. 7F DJUSs with multiple side holes in the straight portion were placed in 58 ureters of 43 patients (Group 1). 8F DJUSs with three side holes in the proximal 2-cm of the straight portion were placed in 83 ureters of 67 patients (Group 2). The incidence of early DJUS dysfunction was compared between the two groups, and nephrostographic findings were evaluated in the cases of early dysfunction. Early dysfunction of the DJUS was noted in 14 of 58 patients (24.1 %) in Group 1, which was significantly higher (p = 0.001) than in Group 2 in which only 1 of 83 patients (1.2 %) had early dysfunction of the DJUS. Nephrostographic findings of early dysfunction included dilatation of the pelvicalyceal system, filling defects in the ureteral stent, and no passage of contrast media into the urinary bladder. In malignant ureteral strictures, multiple side holes in the straight portion of the 7-F DJUS seem to cause early dysfunction. The 8F DJUSs with three side holes in the proximal 2-cm of the straight portion may be superior at preventing early dysfunction.

Application of Self-Expandable Metal Stents for Ureteroileal Anastomotic Strictures: Long-Term Results