In vitro assessment of a novel dual probe ultrasonic intracorporeal lithotriptor.

Purpose: The Cyberwand (Cybersonics, Erie, Pennsylvania) is a novel intracorporeal lithotrite that uses coaxial ultrasonic elements operating at 2 frequencies. We compared this device to the LithoClast(R) Ultra, which we previously noted is the most efficient commercially available intracorporeal lithotripsy device.

Materials And Methods: An in vitro test system was used to assess the efficiency of stone penetration for the Cyberwand and the LithoClast Ultra.

The pathogenesis of calyceal diverticular calculi.

Controversy exists over whether metabolic factors or urinary stasis predominate in the pathogenesis of calyceal diverticular calculi. We performed a study to better define the effects urinary stasis and metabolic abnormalities have in the pathogenesis of calyceal diverticular stones. Twenty-nine patients who underwent percutaneous treatment of calyceal diverticular calculi were studied.

Acute effects of percutaneous tract dilation on renal function and structure.

Background: Percutaneous nephrolithotomy (PCNL) is performed on a routine basis for the rapid and efficient removal of large caliceal stones. After percutaneous puncture, rigid dilators or an inflatable balloon are used to dilate the nephrostomy tract to allow access to the collecting system for stone removal. Little is known of the acute impact of tract dilation procedures on renal function.

The camera phone: a novel aid in urologic practice.

Objectives: To describe a novel use of the camera phone for efficient, reliable, and cost-effective collection and transmission of medical data in the urologic setting.

Methods: We used camera phones (Verizon VGA and Sanyo-Sprint PCS) with a resolution of 640 x 480 pixels to capture images in the operating room, as well as in the outpatient clinic. Images were obtained directly from the monitor or the x-ray viewing box.

Endoscopic evidence of calculus attachment to Randall's plaque.

Purpose: It has been proposed that calcium oxalate calculi begin as small stones attached to the renal papillae at sites of Randall's plaque. However, no study has investigated the prevalence of attached stones in calcium oxalate stone formers or the relationship between stone attachment site and Randall's plaque. In this study we used endoscopic examination of renal papillae in stone formers undergoing percutaneous nephrolithotomy to investigate both issues.

Changing composition of renal calculi in patients with neurogenic bladder.

Purpose: Renal calculi are a significant source of morbidity for patients with neurogenic bladder. Calculi from patients with NB have traditionally been composed primarily of struvite and carbonate apatite secondary to chronic urea-splitting bacteriuria. In the current era there have been great improvements in the urological rehabilitation of patients with NB.

Percutaneous nephrolithotomy for ectopic kidneys: over, around, or through.

Objectives: The treatment of patients with complex urolithiasis in ectopic kidneys can be challenging. Because the location of an ectopic kidney can vary, each case requires a unique and, at times, unconventional approach. We reviewed the techniques we have developed to treat such patients, including laparoscopic-assisted tubeless, transhepatic, and transiliac percutaneous nephrolithotomy (PNL).

Outcomes of hand-assisted laparoscopic nephrectomy in technically challenging cases.

Objectives: To evaluate the outcomes of hand-assisted laparoscopic nephrectomy in patients with significant complicating clinical factors.

Methods: We performed a retrospective review of 322 hand-assisted laparoscopic nephrectomy cases that were completed at a single institution from 1998 to 2004. Patients with a history of extensive abdominal surgery or prior procedures on the affected kidney, evidence of perirenal inflammation, renal lesions 10 cm or more in diameter, or level I renal vein thrombus were included.

Holmium laser enucleation of the prostate for prostates of >125 mL.

Objective: To examine a group of patients treated with holmium laser enucleation of the prostate (HoLEP) and with the bladder outlet obstructed by an exceptionally large (>125 mL) prostate, as such men are often not considered candidates for endoscopic treatments and historically have required open surgery.

Patients And Methods: We analysed retrospectively all patients with prostates of > 125 mL on transrectal ultrasonography (TRUS) who underwent HoLEP between January 2000 and January 2005.

Results: Eighty-six patients were identified; their mean (range) age was 72.

Holmium laser enucleation of the prostate for men with urinary retention.

Purpose: Holmium laser enucleation of the prostate (HoLEP) is an established procedure for the treatment of patients with benign prostatic hyperplasia. We performed a study to examine a group of patients in urinary retention treated by HoLEP.

Materials And Methods: A retrospective analysis of 164 consecutive patients with urinary retention who underwent HoLEP between January 2000 and August 2004 was performed.

Holmium laser enucleation of the prostate: a comparison of efficiency measures at two institutions.

Background And Purpose: Holmium laser enucleation of the prostate (HoLEP) is perceived to be technically difficult, time consuming, and inefficient. We assessed the efficiency of HoLEP by documenting the technical features of the procedure at two hospitals located on different continents.

Patients And Methods: A retrospective analysis of all patients who underwent HoLEP at the Methodist Hospital of Indiana and Tauranga Hospital in New Zealand was performed.

Change in serum prostate specific antigen concentration after holmium laser enucleation of the prostate: a marker for completeness of adenoma resection?

Background And Purpose: Holmium laser enucleation of the prostate (HoLEP) is a well-established technique for the treatment of benign prostatic hyperplasia (BPH). To date, changes in serum prostate specific antigen (PSA) after HoLEP have not been published. We hypothesized that HoLEP produces a diminution in PSA similar to that produced by the gold-standard therapies for BPH.

Using and choosing a nephrostomy tube after percutaneous nephrolithotomy for large or complex stone disease: a treatment strategy.

Background And Purpose: Percutaneous nephrolithotomy (PCNL) is a well-accepted technique for removal of large or complex renal calculi. However, little attention has been paid to strategies for nephrostomy tube (NT) selection. We reviewed the reasons for selecting three types of NT after PCNL for large or complex stone disease.

Simultaneous holmium laser enucleation of prostate and upper-tract endourologic stone procedures.

Background And Purpose: The holmium laser is a versatile urologic tool. Its unique cutting and coagulating properties allow multiple procedures, such as stone fragmentation and laser enucleation of the prostate (HoLEP), to be performed with a single set-up. This paper reviews our experience with simultaneous HoLEP and endourologic upper-tract stone procedures.

High-powered holmium-laser ablation: comparison of setting effectiveness using tissue-surrogate model.

Background And Purpose: The 100-W holmium laser, in conjunction with a sidefiring 550-microm fiber, can ablate prostate glands as large as 40 g to relieve lower urinary-tract symptoms. We evaluated the effect of various setting combinations on ablation efficiency using beef kidney as a tissue-surrogate model.

Materials And Methods: Beef kidney specimens (mean weight 44.

Shock wave lithotripsy of stones implanted in the proximal ureter of the pig.

Purpose: Ureteral stones can be difficult to treat with shock wave (SW) lithotripsy. A strategy for lithotripsy of proximal ureteral stones is to push them back into the renal pelvis prior to administering SWs. However, push-back is invasive and not always possible.

Percutaneous nephrolithotomy for caliceal diverticular calculi: a novel single stage approach.

Purpose: Current percutaneous treatment of symptomatic caliceal diverticular calculi involves renal access, stone removal, dilation of the diverticular communication, fulguration of the cavity and placement of a nephrostomy tube. We reviewed the outcomes of patients undergoing a novel single stage percutaneous nephrolithotomy technique for radiopaque caliceal diverticular stones that eliminates ureteral catheterization and entry into the renal collecting system.

Materials And Methods: A total of 21 patients (8 male and 13 female including 1 bilateral) with a mean age of 42.

Comparison of laparoscopic live donor nephrectomy versus the traditional open technique.

Objectives: Laparoscopic live donor nephrectomy (LDN) is a minimally invasive technique for kidney procurement that may decrease the donor disincentives. In addition, recent studies have demonstrated that LDN has equal graft and recipient survival when compared to the standard open approach. We report our experience with LDN and compare the results with the most recent open donor nephrectomy (ODN) group performed at our institutions.

Shock wave lithotripsy monotherapy for renal calculi.

Shock wave lithotripsy (ESWL) remains the most common treatment for renal calculi. In this article, recent literature pertaining to ESWL monotherapy of renal calculi was reviewed, with the goal of improving ESWL results through better case selection. When selecting the optimal surgical approach for a patient, multiple factors must be considered.

Stone formation is proportional to papillary surface coverage by Randall's plaque.

Purpose: Randall's plaques are common in calcium oxalate (CaOx) stone formers (SF). Plaque coverage correlates directly with urine calcium excretion and inversely with urine volume. We hypothesize that plaque coverage should increase proportionally with increasing stone number.

Transperitoneal laparoscopic pyelolithotomy after failed percutaneous access in the pediatric patient.

Purpose: We present our experience with transperitoneal laparoscopic pyelolithotomy in pediatric patients in whom percutaneous renal access failed and the stone burden warranted open intervention.

Material And Methods: A transperitoneal laparoscopic approach was used for pyelolithotomy in 8 patients 3 months to 10 years old (mean age 4 years). Percutaneous access failed secondary to a nondilated system and/or an occluding lower pole calculus.

An update on ureteroscopic instrumentation for the treatment of urolithiasis.

Purpose Of Review: Ureteroscopic instruments, both endoscopic and working devices, continue to evolve. Changes in instrumentation have necessitated concurrent modifications in ureteroscopic techniques over the years. The safety and efficacy of the ureteroscopic approach for the treatment of renal and ureteral calculi, however, have continued to improve.

In vitro assessment of lithoclast ultra intracorporeal lithotripter.

Purpose: The Lithoclast Ultra (Boston Scientific Corporation, Natick, MA) enables the simultaneous application of ultrasonic and pneumatic modalities for the fragmentation and removal of stones during percutaneous nephrolithotomy (PCNL). We evaluated the effectiveness of this unit using a hands-free in vitro testing system.

Materials And Methods: An in vitro test system was used to assess the efficiency of stone penetration when the Lithoclast Ultra was operated at different settings of ultrasonic power and pneumatic frequency.

The use of blunt-tipped 12-mm trocars without fascial closure in laparoscopic live donor nephrectomy.

Objectives: Blunt-tipped trocar placement may eliminate the need for fascial closure in transperitoneal laparoscopic live donor nephrectomies (LDN). The process of 12-mm blunt-tipped trocar insertion through the abdominal wall involves fascial and muscle spreading, not incision. Coaptation of the tissue layers occurs during withdrawal of the trocar, preventing volume gaps that can be prone to herniation.

Renal nerves mediate changes in contralateral renal blood flow after extracorporeal shockwave lithotripsy.

Renal blood flow falls in both kidneys following delivery of a clinical dose of shockwaves (SW) (2000 SW, 24 kV, Dornier HM3) to only one kidney. The role of renal nerves in this response was examined in a porcine model of renal denervation. Six-week-old pigs underwent unilateral renal denervation.