Stenting the Male Lower Urinary Tract: A Novel Idea with Much Promise

The North American experience with the UroLume endoprosthesis as a treatment for benign prostatic hyperplasia: long-term results. The North American UroLume Study Group

OBJECTIVES

To determine the efficacy and safety of the UroLume endoprosthesis as a treatment for obstructive benign prostatic hyperplasia in healthy men.

METHODS

One hundred twenty-six men were enrolled prospectively in a multicenter North American Clinical Trial. Ninety-five men (mean age 68 +/- 7 years) had moderate or severe prostatism, whereas 31 participants (mean age 76 +/- 8 years) were in urinary retention. Voiding function for all patients was assessed prior to stent placement and in follow-up at 1, 3, 6, 12, and 24 months with the Madsen-Iversen symptom questionnaire, peak urinary flow rate, postvoid residual urine volume, and cystoscopic examination.

RESULTS

For the nonretention cohort at 24-month follow-up, the results were as follows: (1) total symptom score decreased from 14.3 +/- 0.5 preinsertion to 5.4 +/- 0.5 (p < 0.001); (2) peak urinary flow rate increased from 9.1 +/- 0.5 mL/s preinsertion to 13.1 +/- 0.7 mL/s (p < 0.001); and (3) postvoid residual urine volume decreased from 85 +/- 9 mL to 47 +/- 8 mL (p = 0.02). For the retention group, the total symptom score, peak urinary flow rate, and postvoid residual urine volume at 24 months were 4.1 +/- 0.5, 11.4 +/- 1.0 mL/s and 46 +/- 7 mL, respectively. By 12-month follow-up, most endoprostheses were completely covered with urothelium. Although significant long-term complications were minimal, 17 endoprostheses have been explanted for an overall removal rate of 13%. All devices were removed transurethrally without subsequent sequelae to the external urinary sphincter or urethra.

CONCLUSIONS

The long-term results from this North American Clinical Trial suggest that the UroLume endoprosthesis can be an effective and safe treatment for properly selected healthy men with obstructive benign prostatic hyperplasia. Randomized clinical trials comparing this minimally invasive procedure with transurethral resection of the prostate are now underway to document further its efficacy and safety.

Use of Memokath, a second generation urethral stent for relief of urinary retention in male spinal cord injured patients

Memokath (Engineers & Doctors A/S, Hornbaek, Denmark) a second generation urethral stent composed of titanium nickel alloy with shape memory effect was deployed in 10 male spinal cord injured patients with urinary retention. The stent was inserted under sterile conditions via a delivery catheter under fluoroscopic control in seven and with the aid of a flexible cytoscope in three. The proximal end of the stent was positioned at the bladder neck and 50 ml of normal saline at 45 degrees C was flushed through the stent which resulted in expansion of the distal most four coils of the stent in the proximal bulbar urethra; thus the internal sphincter (bladder neck) and external sphincter zone were kept open by the stent. Urethral stenting helped to achieve complete vesical emptying in all 10 patients. The complications included transient autonomic dysreflexia in two, transient urinary retention due to blood clot in one, and acute urinary tract infection in one patient. With a follow up of 3-7 months, all 10 patients have been asymptomatic, with residual urine of less than 50 ml. There has been no migration or blocking of the stent. However, these stents require replacement at 12-18 months, but it is a short procedure as the Memokath, when cooled with saline at 4 degrees C, becomes supersoft, enabling its easy and nontraumatic removal.(ABSTRACT TRUNCATED AT 250 WORDS)