The Impact of Ureteral Access Sheath Use on the Development of Abnormal Postoperative Upper Tract Imaging after Ureteroscopy.

PURPOSE: Ureteral access sheaths are commonly used during ureteroscopy to facilitate stone removal, improve visibility and maintain low intrarenal pressures. However, the use of a ureteral access sheath can cause ureteral wall ischemia and ureteral tears, potentially increasing the risk of postoperative ureteral stricture and obstruction. We studied the impact of ureteral access sheath use on postoperative imaging studies. Secondary objectives included studying the impact of other intraoperative parameters on postoperative imaging studies. MATERIALS AND METHODS: A retrospective chart review was conducted of cases that underwent ureteroscopy for nephroureterolithiasis across 2 high volume institutions between January 2012 and September 2016. Patient demographics, cumulative stone size, operative time, use of ureteral access sheath, laser lithotripsy, basket extraction, preoperative ureteral stent and postoperative ureteral stent placement were extracted from the electronic medical record. Findings of followup renal ultrasound, kidney-ureter-bladder x-ray and/or computerized tomography at approximately 8 weeks after surgery were recorded. RESULTS: A total of 1,332 ureteroscopies were performed with 1,060 cases (79.6%) returning for routine upper tract imaging after ureteroscopy. Postoperative hydronephrosis was noted following 127 cases (12.0%). Factors predicting presence of hydronephrosis after ureteroscopy include lower body mass index (p=0.0016), greater cumulative stone size (p=0.0003), increased operative time (p <0.0001), preoperative ureteral stent (OR 1.49, p=0.0299) and postoperative ureteral stent placement (OR 6.43, p=0.0031). Postoperative hydronephrosis was not associated with use of ureteral access sheath, age, laser lithotripsy or basket extraction. CONCLUSIONS: Use of ureteral access sheath did not have a significant impact on development of postoperative hydronephrosis, suggesting ureteral access sheath is safe for use during ureteroscopy. Ureteral strictures remain rare following ureteroscopy, seen in only 1.0% of our cohort. With an observed prevalence of hydronephrosis of 12.0% on followup imaging at 8 weeks, routine upper tract imaging after ureteroscopy remains a valuable prognostic tool.

Holmium-YAG laser: impact of pulse energy and frequency on local fluid temperature in an in-vitro obstructed kidney calyx model.

During laser lithotripsy, energy is transmitted to both the stone and the surrounding fluid. As the energy is delivered, the temperature will rise. Temperatures ≥60 ° C can cause protein denaturation. The objective of this study is to determine the time it takes from body temperature (37°C) to 60°C at various laser power settings. A Flexiva TracTip 200 optical fiber was submerged alongside a negative temperature coefficient-type thermistor in 4 mL of saline in a glass test tube. A Lumenis VersaPulse Powersuite 100-W holmium:yttrium aluminum garnet laser was activated at 0.2- to 1.5-J pulse energies, 6- to 50-Hz frequencies, and 2- to 22.5-W average power. Temperature readings were recorded every second from 37°C until 60°C. Time and heating rate were measured. The procedure was repeated three times for each setting. Average time from 37°C to 60°C for settings (1) 0.2 J/50 Hz, (2) 0.6 J/6 Hz, (3) 1 J/10 Hz, and (4) 1.5 J/10 Hz was 60.3, 172.7, 58, and 43.3 s, respectively. Time from 37°C to 60°C decreased as frequency increased for every given pulse energy. Average heating rate increased proportionally to power from 0.06°C/s at 2 W to 0.74°C/s at 22.5 W. During laser lithotripsy, there is a rapid increase in the temperature of its surrounding fluid and temperatures ≥60 ° C may be reached. This could have local tissue effects and some caution with higher power settings should be employed especially where irrigation is limited. Further studies incorporating irrigation and live tissue models may aid to further define the risks.

Testosterone supplementation does not worsen lower urinary tract symptoms.

PURPOSE: Testosterone replacement therapy is commonly used to treat men with hypogonadism. However, there has been caution in using testosterone replacement therapy in men with moderate to severe lower urinary tract symptoms for fear of worsening the symptoms. In this study we examine the effect of testosterone replacement therapy on lower urinary tract symptoms in hypogonadal men. MATERIALS AND METHODS: We retrospectively reviewed our outpatient database and identified patients with a diagnosis of hypogonadism who received testosterone replacement therapy from 2002 to 2012. Lower urinary tract symptoms were assessed using the AUASI (American Urological Association symptom index) before and after testosterone replacement therapy. Testosterone and prostate specific antigen were also continuously measured, and all patients were closely monitored for side effects of testosterone replacement therapy. Patients who had progression of lower urinary tract symptoms to the point of requiring surgery were included in the study. RESULTS: We identified 120 hypogonadal men who received testosterone replacement therapy, the majority of whom had topical therapy or a combination of topical and pellet based therapy (57.5% and 20.8%, respectively). Mean baseline AUASI (±SD) was 10.8 (±7.8) and mean duration of testosterone replacement therapy was 692 days (±773). Mean change in AUASI was -1.07 (±6.06). Mean baseline prostate specific antigen was 1.6 ng/dl (±1.9) and mean change in prostate specific antigen was 0.44 (±2.2). Of the patients 8.1% had a baseline prostate specific antigen greater than 4.0 ng/dl, and these patients had greater improvement in AUASI than those with a baseline prostate specific antigen less than 4.0 ng/dl (-1.9 vs -1.0, p not significant). Overall 45.8% of patients had a less than 3-point change in AUASI in either direction. Of the 120 patients 38 (31.7%) had improvement in AUASI 3 or more points while 27 (22.5%) had worsening of AUASI 3 or more points. Patients with an improved AUASI had a mean prostate specific antigen change of 0.3 (±3.4), while those who had worsening of AUASI had a mean prostate specific antigen change of 0.7 (±2.2) (p not significant). Approximately 9 of 120 (7.5%) of these men initiated new medications for lower urinary tract symptoms during the course of the study. There was no significant change in AUASI compared to patients without any use of lower urinary tract symptoms medications. In addition, 4 (3.3%) patients had progression of lower urinary tract symptoms and required transurethral resection of the prostate. CONCLUSIONS: We demonstrate that initiating testosterone replacement therapy in hypogonadal men involves a low risk of worsening lower urinary tract symptoms. In fact, many men experience symptom improvement while changes in prostate specific antigen appear minor. Future research should focus on larger patient population studies to further examine this relationship.