A short biodegradable helical spiral ureteric stent provides better antireflux and drainage properties than a double-J stent.

OBJECTIVE: The use of ureteric stents is a standard treatment for the relief of ureter blockages for benign or malignant reasons. The most common stent design in clinical use is a double-J stent with coiled ends to avoid stent displacement. However, there are a number of complications associated with stent use. A double-J stent design bypasses the ureterovesical junction, enables bladder pressure reflection to the renal pelvis and causes vesicoureteral reflux (VUR). This may result in scarring and renal failure. MATERIAL AND METHODS: An animal model was used to investigate whether VUR can be avoided in stented ureters using a short biodegradable partial helical spiral stent design that leaves the ureterovesical junction intact. MATERIALS AND METHODS: Eight female pigs were used. Ureters on the left side were stented using a short helical spiral SR-PLGA stent (group A) and ureters on the right side using double-J stents (group B). Simulated voiding cystoureterography and standard intravenous urography examinations were performed on all eight animals at 4 weeks and on the remaining four animals at 8 weeks. RESULTS: An SR-PLGA single coiled partial stent demonstrated superior drainage properties to a double-J stent at 4 weeks (p = 0.020). A marked but not statistically significant difference in favour of a SR-PLGA stent was also observed at 8 weeks (p = 0.102). A statistically significant difference was observed in VCUG findings in favour of group A at immediate postoperative control as well as in the 4 and 8 week follow-up studies (p = 0.011, p = 0.010, p = 0.046, respectively). CONCLUSION: A self-expandable, SR-PLGA partial ureteric stent presented with superior drainage and antireflux properties compared to a double-J stent. The reflux commonly related to double-J stent use can be minimized by using a partial ureteric stent design.

Drainage and antireflux characteristics of a biodegradable self-reinforced, self-expanding X-ray-positive poly-L,D-lactide spiral partial ureteral stent: an experimental study.

PURPOSE: To evaluate the drainage and antireflux characteristics of a new self-expandable self-reinforced poly-L,D-lactide partial ureteral stent (SR-PLA 96) in an experimental model. MATERIALS AND METHODS: Twelve dogs were used as experimental animals. A low-midline laparotomy and cystotomy were performed on all animals. In group A (six animals), 50-mm long SR-PLA 96 ureteral stents with a double-helical spiral design were inserted into both ureters, leaving the lower ends 2 cm above the ureterovesical junction. In group B (six animals), both ureters were stented with traditional pigtail stents (C-Flex) Double-J; Cook Urological), which were removed 8 weeks after surgery. Renal function and ureteral patency were evaluated by dynamic kidney imaging and urography examinations at 6 and 12 weeks postoperatively. The degrees of vesicoureteral reflux at two levels of the ureters and at the level of the renal pelvis were evaluated by nuclear voiding cystograms at 6 weeks. RESULTS: The partial SR-PLA 96 stent design showed more favorable antireflux properties that the Double-J stent design. The degree of vesicoureteral reflux, reflected in an increase of nuclear enhancement at 6 weeks, was lower in the distal (7.9% +/- 14.7% v 63.2% +/- 17.3%; P < 0.05) and middle (6.1% +/- 8.1% v. 45.5% +/- 19.5%; P = 0.15) levels of the ureters as well as at the level of the renal pelvis (-3.4% +/- 3.6% v 6.2% +/- 3.9%; P = 0.65) than in the Double-J-stented ureters. No significant differences in renal function or ureteral patency were observed at 12 weeks after the Double-J stents had been removed and the SR-PLA 96 stents had fragmented. CONCLUSION: A self-expandable, self-reinforced SR-PLA 96 partial ureteral stent showed more favorable antireflux properties than a Double-J stent.

Sexual function of LUTS patients before and after neodymium laser prostatectomy and transurethral resection of prostate. A prospective, randomized trial.

OBJECTIVE: To assess and compare the sexual function of patients undergoing transurethral resection of the prostate (TURP) or Nd:YAG laser treatment for lower urinary tract symptoms (LUTS) caused by obstructing benign prostatic hyperplasia (BPH). PATIENTS AND METHODS: 98 LUTS patients with urodynamically confirmed bladder outlet obstruction were recruited. Patients were randomised to TURP and laser treatment, which was further divided to contact and hybrid treatments according to prostate size. The sexual function at baseline and at 1 year postoperatively was assessed from the Danish Prostate Symptom Score Sexual Function Questionnaire (DanPSS Sex) items concerned with erectile stiffness, ejaculatory volume and pain or discomfort on ejaculation. RESULTS: The sexual function data at 1 year was available for 83 patients. At baseline, a high prevalence of erectile dysfunction (86%), ejaculatory volume change (83%) and pain or discomfort on ejaculation (26%) was observed and considered problematic by 79%, 63% and 100% of men, respectively. An increase of total impotence in the TURP group was observed (p = 0.046). TURP decreased or totally eradicated the amount of ejaculate, which was the only difference found between the study groups (p < 0.001). Both laser and TURP treatments improved pain or discomfort on ejaculation. CONCLUSIONS: The prevalence of sexual dysfunction in patients with symptomatic infravesical obstruction caused by BPH is high and perceived mostly as bothersome. TURP, Nd:YAG contact or hybrid laser treatments did not increase erectile dysfunction but improved pain or discomfort on ejaculation. The only significant difference between these treatments in respect to sexual function was a higher incidence of decreased or absent ejaculate after TURP.

Long-term results of contact laser versus transurethral resection of the prostate in the treatment of benign prostatic hyperplasia with small or moderately enlarged prostates.

OBJECTIVE: To evaluate the long-term results of contact laser vaporization (CLV) of the prostate and transurethral resection of the prostate (TURP) in patients with symptomatic bladder outflow obstruction (BOO) caused by benign prostatic hyperplasia (BPH) with prostates smaller than 40 ml. MATERIAL AND METHODS: A total of 52 patients with lower urinary tract symptoms (LUTS) and urodynamically confirmed BOO caused by BPH with glands smaller than 40 ml were treated by means of CLV or TURP in a randomized trial. Changes in symptom score, urodynamics and prostate volume were evaluated during a 4-year follow-up period. RESULTS: A total of 42 (81%) of the patients were available for review at 4 years. The re-operation rate was 1/26 for each treatment. A sustained improvement in median Danish Prostate Symptom Score was seen in the laser group from 18 (range 5-54) to 5 (0-34) and in the TURP group from 18 (4-46) to 4 (0-18) (p<0.001 for both). A sustained improvement in maximum urinary flow rate was also seen in the laser group from 8.3 (4.8-19.6) ml/s to 14.3 (10.1-33.6) ml/s (p<0.001) and in the TURP group from 8.6 (5.0-15.9) ml/s to 16.1 (7.7-39.6) ml/s (p<0.01), without differences between the study groups. Median detrusor pressure at maximum urinary flow rate decreased significantly after both treatments, in the CLV group from 64 (32-112) cmH2O to 38 (18-65) cmH2O and in the TURP group from 57 (40-137) cmH2O to 28 (9-44) cmH2O (p<0.001 for both), and at 48 months was significantly higher in the laser group (p<0.01). At 4 years, 7/22 (32%) of the laser patients and 2/20 (10%) of the TURP patients were urodynamically obstructed. Post-void residual at 48 months was significantly lower in the TURP group than in the CLV group. Median prostate volume was smaller after TURP at 6 and 48 months (p<0.05). CONCLUSIONS: Long-term data of CLV and TURP treatments for BPH with small or moderately enlarged prostates indicate no significant difference in the relief of symptoms or in the rate of re-operations. However, the number of patients in this study was small and consequently the power to detect differences between the study groups was low. Regarding most objective outcome parameters, long-term follow-up revealed a slight advantage of TURP over CLV.

Patients with acute flank pain: comparison of MR urography with unenhanced helical CT.

PURPOSE: To compare unenhanced helical computed tomography (CT) and magnetic resonance (MR) urography, by using T2-weighted and contrast material-enhanced T1-weighted imaging to examine patients with acute flank pain, with reference to excretory urography and final clinical diagnosis. MATERIALS AND METHODS: Forty-nine patients underwent CT, MR urography (with T2-weighted and gadopentetate dimeglumine-enhanced T1-weighted sequences), and excretory urography. CT and MR urographic findings were evaluated separately and independently by two radiologists each (CT, observers A and B; MR urography, observers C and D) for the presence, cause, level, and degree of obstruction. The final conclusive diagnosis was based on the combination of excretory urographic, clinical, and interventional results. RESULTS: At final diagnosis, 32 (65%) patients were found to have ureteral stones causing unilateral obstruction. In ureteral stone detection, the sensitivity and specificity of CT were 90.6% (29 of 32 patients) and 100.0% (17 of 17 patients), respectively (observer A) and 90.6% (29 of 32 patients) and 94.1% (16 of 17 patients), respectively (observer B), while those of MR urography were 93.8% (30 of 32 patients) and 100.0% (17 of 17 patients), respectively (observer C) and 100.0% (32 of 32 patients) and 100.0% (17 of 17 patients), respectively (observer D). Spearman correlation coefficients for stone size at CT were 0.76 (P <.001) and 0.75 (P <.001) and at MR urography, 0.49 (P =.005) and 0.51 (P =.004). CONCLUSION: In routine clinical practice, CT is the modality of choice in the evaluation of patients with acute flank pain. MR urography is an accurate and suitable alternative imaging technique in selected patients.