Derek Weiland

A pilot study on the early use of the vacuum erection device after radical retropubic prostatectomy

To evaluate the effect of the early use of the vacuum erection device (VED) on erectile dysfunction (ED) and penile shortening after radical retropubic prostatectomy (RP), as these are important concerns for men choosing among treatment alternatives for localized prostate cancer.

Lithogenic Risk Factors in the Morbidly Obese Population

PURPOSE To our knowledge baseline lithogenic risk factors in the morbidly obese population are currently unknown. Prior studies evaluated known stone formers and correlated risk with increasing body mass index. We describe risk factors for urinary stone formation in a group of unselected morbidly obese patients. MATERIALS AND METHODS Patients scheduled for gastric bypass provided a 24-hour urine collection before surgery. Patient demographics, medications and supplement consumption were recorded. A dietary intake diary was converted into daily kcal, Ca, Na and protein consumption. Differences between groups based on gender, history of diabetes or nephrolithiasis, diuretic use and Ca supplementation were evaluated. Correlation of stone risk parameters with body mass index was evaluated. RESULTS A total of 45 patients provided samples for analysis. Mean +/- SD body mass index was 49.5 +/- 9.1 kg/m(2) and mean age was 47.0 +/- 10.5 years. Overall 97.8% of patients had at least 1 lithogenic risk factor identified. Low urinary volume was the most common abnormality, affecting 71.1% of patients. Male patients excreted significantly more Ox (p = 0.0014), Na (p = 0.020), PO(4) (p = 0.0083) and SO(4) (p = 0.0014) than females. Patients with a history of nephrolithiasis excreted significantly more oxalate (p = 0.018) and had higher relative Na urate supersaturation (p = 0.00093) than nonstone formers. Hydrochlorothiazide use was associated with significantly increased Na urate relative supersaturation (p = 0.0097). Increasing body mass index was inversely associated with Mg (r = -0.38, p = 0.01) and brushite (r = -0.30, p = 0.04). CONCLUSIONS Of our cohort of morbidly obese patients 98% had at least 1 lithogenic risk factor identified on 24-hour urine collection. This study identified a high urinary stone risk in the morbidly obese and suggests possible avenues for dietary and/or pharmacological preventive measures. Future studies will determine how bariatric surgery alters these risk factors.

Impact of Irrigation Systems on Stone Migration

PURPOSE To evaluate forces exerted on a stone with different ureteroscopic irrigation systems that could impact stone migration during ureteroscopy. MATERIALS AND METHODS A 3-mm steel simulated stone was welded to a 3F stone basket. The basket wire was then backloaded into the working channel of a 4.5F Wolf semirigid ureteroscope. The basket shaft was attached to a 50 g load cell. The ureteroscope was placed in a ureteral model (14F silicon tubing). Simulated blood was dripped adjacent to the stone at 12 drops/min. Endo-irrigation devices were attached to the ureteroscope, and irrigation was applied at a rate sufficient to maintain visualization of the stone. Force on the stone was measured with the following endo-irrigation systems: Gravity (183 cm H2O); pressurized irrigation (150 mm Hg, 300 mm Hg); Kosin Technology Universal Piggyback Irrigation System (UPIS) at gravity (183 cm H2O), 150 mm Hg and 300 mm Hg; EMS Medical Peditrol Foot Pump; Cook Ureteroscopy Irrigation System; ACMI Irri-Flo Irrigation Delivery System; and Boston Scientific Single-Action-Pump System (SAPS). RESULTS SAP required the least number of pumps (0.35/sec) to maintain a clear endoscopic field while the Peditrol device required the most (1.88/sec). Pulse duration was longest for the ACMI (1.6 sec) and shortest for pressurized gravity and UPIS (<0.3 sec). The average total maximum impulse during a pump was significantly greater with the Cook (0.017 Ns) and ACMI (0.027 Ns) systems. On average, gravity-based systems applied the least amount of force, < or =0.0006 Ns, maximum impulse at any given time. CONCLUSIONS Gravity-based systems exert less force than hand-held and foot-pump devices. Of the hand-held devices, the SAP exerted the least average maximum impulse on the stone.

Angiomyofibroblastoma‐like tumors (cellular angiofibroma)

Abstract  Angiomyofibroblastoma‐like tumor (cellular angiofibroma) is a rare, circumscribed, slow‐growing mesenchymal tumor that occurs predominantly in the vulva, perineum, and pelvis of women. We report two cases of this tumor in men arising as paratesticular masses of the scrotum, summarize the history of this tumor, and discuss why efforts should be made to differentiate it from aggressive angiomyxoma. Recommended treatment is complete surgical excision with long‐term follow up exams, as local recurrence may occur many years after resection of the lesion.

Intrarenal manipulation of flexible ureteroscopes: a comparative study

To compare the relative ease of manipulation around a calyceal model in the hands of experienced ureteroscopists of four flexible ureteroscopes (FUs), as new‐generation FUs provide exaggerated active deflection to facilitate intrarenal manipulation.

Medical devices used for ureteroscopy for renal calculi.

Urinary stone disease is a problem as old as human civilization. In this article, a brief history of stone disease and the current status of urinary stone disease treatment will be discussed. This review will focus primarily on the newest technology and devices associated with flexible ureteropyeloscopy for the treatment of upper tract urinary stones. In addition to defining the cutting-edge technology that is newly available, this review will glimpse at what technologic advances are expected in the near future. Reference articles that do a good job of defining the current state of flexible ureteropyeloscopy technology and urinary stone disease treatment will be highlighted, along with a reiteration of the major points of the article.

Randomized prospective evaluation of nephrostomy tube configuration: impact on postoperative pain

OBJECTIVE Conduct a prospective randomized single-blind comparison of two nephrostomy catheter designs, evaluating specifically intraoperative placement and postoperative comfort. MATERIALS AND METHODS The single-blind, prospective randomized trial was conducted with institutional review board approval. All patients undergoing percutaneous nephrolithotomy who gave informed consent were randomized to placement of either a Boston Scientific Flexima 8.3F pigtail nephrostomy tube #27-180 (PIG) or a Boston Scientific 8.2F nephroureteral stent #410-126 (NUS). Randomization was concealed from the surgeon until time of placement. Subjective intraoperative placement characteristics were rated by the surgeon on a scale of 1 = excellent, 2 = fair, 3 = good and 4 = poor. The patients postoperative pain intensity was evaluated with a Visual Analog Pain Score (0 = no pain to 10 = worst pain). RESULTS Nine patients were randomized to each group. The PIG group was rated significantly better than the NUS group with regards to ease of placement (p = 0.007) and radiopacity of the tube (p = 0.007) by surgeon. Visual analog pain scores on postoperative day one, was significantly lower in the PIG group (mean = 2+/-2) than the NUS group (mean = 5+/-1) (p =0.004). The mean amount of intra-venous morphine equivalent given in the PIG group (mean = 1+/4 Eq morphine) was less on average compared to the NUS group (mean = 6+/13 Eq morphine), but the differences did not reach statistical significance (p = 0.06). CONCLUSIONS Following percutaneous nephrolithotomy, use of a small pig-tail nephrostomy tube results in greater ease of placement and less postoperative pain than a nephroureteral catheter.

Laparoscopic ureterectomy for the management of painful calculi in a ureteral stump

Abstract

Eighteen-year experience with the Medstone STS lithotripter: safety, efficacy, and evolving practice patterns.

OBJECTIVE To evaluate trends in safety, efficacy, and practice patterns for shockwave lithotripsy (SWL) procedures performed during a 18-year period and correlate the findings with recent evidence-based practice guidelines. MATERIALS AND METHODS From January 1988 to June 2006, 66,819 SWLs were performed using the Medstone STS lithotripter in patients with radiologic evidence of stones in the kidney or ureter. Treatment characteristics, such as stone location and size, need of re-treatment, and final success rate were recorded. The procedures were further divided by year for statistical consideration. Statistical analysis was performed using Student t test; P < 0.05 was considered significant. RESULTS Overall SWL success rate was 85% (39,667/46,669), and the overall re-treatment rate was 7.2% (3,417/46,669). There was no significant change in the overall proportion of lower-pole calculi managed with SWL, although there was a significant decrease in the proportion of SWL used for lower calix stones larger than 16 mm in the time period after 2000 (P = 0.006). There was a steady increase in the number of procedures performed for renal calculi in other locations per year, in particular for intrarenal calculi smaller than 20 mm. Intrarenal stones larger than 30 mm decreased as a proportion of procedures per year (P = 0.048) There was no significant change in the proportion of upper and distal ureteral stones managed, corresponding to a solid plateau in the percentage of SWL performed per year. CONCLUSION Our study did not demonstrate an overall drop in SWL; however, it did show the interference of endoscopic procedures on two case scenarios. There was a significant decrease (P = 0.048) in SWL for renal stones larger than 30 mm, and the same trend was noted for lower calix stones larger than 15 mm (P = 0.06).