Gender-related differences in the risk factors for repeat stone surgery.

Our objective was to analyze and compare the associations between potential risk factors for nephrolithiasis and repeat stone surgery in male and female patients. We retrospectively analyzed 1970 patients who had stone surgery at our institution in the period from January 2009 to May 2017, were older than 18 years and had at least 12 months of postoperative follow-up. Our definition of surgical recurrence included repeat surgery on the same renal unit or on the opposite renal unit if the original imaging did not demonstrate significant stones on that side. Uni- and multivariate Cox regression models were built for each gender. We also explored the interactions between gender and other patient's characteristics in their effect on the risk of recurrence. Ureteroscopy was the most common treatment modality for both first (83%) and repeat (87%) procedures. Over a mean follow-up of 4.3 years (median 3.8, interquartile range 2.2-6.0), 413 (21.0%) patients had a surgical recurrence. In multivariate analyses, hypertension, diabetes, Caucasian race and younger age (less than 60 years) were significantly associated with the risk of surgical recurrence only in females. Interaction between these characteristics and gender was significant indicating a larger effect on the risk of surgical recurrence in females compared to males. Our study demonstrated a number of differences in the predictors of repeat surgery for nephrolithiasis between males and females. If confirmed by future studies these differences may be helpful for optimizing nephrolithiasis prevention efforts.

Multi-quadrant biopsy technique improves diagnostic ability in large heterogeneous renal masses. Abel EJ, Heckman JE, Hinshaw L, Best S, Lubner M, Jarrard DF, Downs TM, Nakada SY, Lee FT Jr, Huang W, Ziemlewicz T.J Urol. 2015 Oct;194(4):886-91. [Epub 2015 Mar 30]. doi: 10.1016/j.juro.2015.03.106.

PURPOSE: Percutaneous biopsy obtained from a single location is prone to sampling error in large heterogeneous renal masses, leading to nondiagnostic results or failure to detect poor prognostic features. We evaluated the accuracy of percutaneous biopsy for large renal masses using a modified multi-quadrant technique vs. a standard biopsy technique. MATERIALS AND METHODS: Clinical and pathological data for all patients with cT2 or greater renal masses who underwent percutaneous biopsy from 2009 to 2014 were reviewed. The multi-quadrant technique was defined as multiple core biopsies from at least 4 separate solid enhancing areas in the tumor. The incidence of nondiagnostic findings, sarcomatoid features and procedural complications was recorded, and concordance between biopsy specimens and nephrectomy pathology was compared. RESULTS: A total of 122 biopsies were performed for 117 tumors in 116 patients (46 using the standard biopsy technique and 76 using the multi-quadrant technique). Median tumor size was 10cm (IQR: 8-12). Biopsy was nondiagnostic in 5 of 46 (10.9%) standard and 0 of 76 (0%) multi-quadrant biopsies (P = 0.007). Renal cell carcinoma was identified in 96 of 115 (82.0%) tumors and nonrenal cell carcinoma tumors were identified in 21 (18.0%). One complication occurred using the standard biopsy technique and no complications were reported using the multi-quadrant technique. Sarcomatoid features were present in 23 of 96 (23.9%) large renal cell carcinomas studied. Sensitivity for identifying sarcomatoid features was higher using the multi-quadrant technique compared to the standard biopsy technique at 13 of 15 (86.7%) vs. 2 of 8 (25.0%) (P = 0.0062). CONCLUSIONS: The multi-quadrant percutaneous biopsy technique increases the ability to identify aggressive pathological features in large renal tumors and decreases nondiagnostic biopsy rates.

Factors associated with patient recall of individualized dietary recommendations for kidney stone prevention.

BACKGROUND/OBJECTIVES: Dietary approaches to preventing the recurrence of idiopathic calcium-containing kidney stones are effective. However, a lifelong commitment to prevention is challenging for many patients. Multiple patient factors likely account for compliance and adherence with dietary recommendations. We examined patients' recall and compliance with dietary recommendations provided during clinical evaluation. SUBJECTS/METHODS: Of 275 patients who received dietary recommendations from a dietitian, 112 completed an investigator-designed survey querying their recollection of dietary recommendations. Patients' responses were compared with the recommendations actually provided as entered in patients' medical records. RESULTS: Patients (62% male, 56±13 years; 38% female, 52±14 years) were provided 3.4±1.1 recommendations (min-max, 1-6) and recalled 67% of recommendations. Highest recalls were for (i) lower meat/fish/poultry intake, (ii) higher fluid intake and (iii) lower sodium (⩾68% for all). Lowest recalls were for weight loss, using citrus juices and increasing fruits/vegetables (⩽61% for all). Forty-seven percent of patients given 1-3 recommendations recalled 100%, whereas only 23% of patients provided >3 recommendations did so (P=0.011). Even though 38% of patients reported some difficulty following dietary recommendations, nearly all (91%) said that they were willing to continue following them. CONCLUSIONS: Higher patient recall is associated with ⩽3 dietary recommendations. Patient recall of recommendations that were not actually provided ('false recall') may contribute to reduced recall and confusion about the most important dietary strategies to reduce their stone risk. Accordingly, providers should prioritize the most important dietary recommendations, reserving those less important for follow-up, and address any confusion patients have from information received prior to evaluation.

Lower pole I: a prospective randomized trial of extracorporeal shock wave lithotripsy and percutaneous nephrostolithotomy for lower pole nephrolithiasis-initial results.

PURPOSE: The efficacy of shock wave lithotripsy and percutaneous stone removal for the treatment of symptomatic lower pole renal calculi was determined. MATERIALS AND METHODS: A prospective randomized, multicenter clinical trial was performed comparing shock wave lithotripsy and percutaneous stone removal for symptomatic lower pole only renal calculi 30 mm. or less. RESULTS: Of 128 patients enrolled in the study 60 with a mean stone size of 14.43 mm. were randomized to percutaneous stone removal (58 treated, 2 awaiting treatment) and 68 with a mean stone size of 14.03 mm. were randomized to shock wave lithotripsy (64 treated, 4 awaiting treatment). Followup at 3 months was available for 88% of treated patients. The 3-month postoperative stone-free rates overall were 95% for percutaneous removal versus 37% lithotripsy (p <0.001). Shock wave lithotripsy results varied inversely with stone burden while percutaneous stone-free rates were independent of stone burden. Stone clearance from the lower pole following shock wave lithotripsy was particularly problematic for calculi greater than 10 mm. in diameter with only 7 of 33 (21%) patients becoming stone-free. Re-treatment was necessary in 10 (16%) lithotripsy and 5 (9%) percutaneous cases. There were 9 treatment failures in the lithotripsy group and none in the percutaneous group. Ancillary treatment was necessary in 13% of lithotripsy and 2% percutaneous cases. Morbidity was low overall and did not differ significantly between the groups (percutaneous stone removal 22%, shock wave lithotripsy 11%, p =0.087). In the shock wave lithotripsy group there was no difference in lower pole anatomical measurements between kidneys in which complete stone clearance did or did not occur. CONCLUSIONS: Stone clearance from the lower pole following shock wave lithotripsy is poor, especially for stones greater than 10 mm. in diameter. Calculi greater than 10 mm. in diameter are better managed initially with percutaneous removal due to its high degree of efficacy and acceptably low morbidity.

Hand-assisted laparoscopic radical nephrectomy: comparison to open radical nephrectomy.

OBJECTIVES: Hand-assisted laparoscopic surgery is easier to learn than standard laparoscopy and simplifies intact specimen removal. We present our experience performing hand-assisted laparoscopic radical nephrectomy (HALRN) and compare it with contemporary open radical nephrectomy performed at our institution. METHODS: We performed 18 HALRNs for renal tumors ranging in size from 2 to 11 cm (average 4.5). Patients ranged in age from 40 to 83 years (average 62.9). All patients underwent HALRN with intact removal through a 7 to 8-cm vertical midline incision through an impermeable wound protector. Two or three working ports were used. We retrospectively compared our results with the results of 18 open radical nephrectomies performed during the same period, with the patients matched for age, body mass index, and American Society of Anesthesiologists' score. RESULTS: In the HALRN group, the average operating room time was 220.5 minutes, average length of stay 3.9 days, average time to return to normal activity 15.8 days, and average time to return to work 26.8 days. The median time to return to 100% normal was 28.0 days. No conversions or re-explorations were necessary in the HALRN series. The final pathologic examination revealed renal cell carcinoma in 15, oncocytoma in 1, angiomyolipoma in 1, and a complex cyst in 1. At a maximum of 48 months of follow-up (average 12.2), no recurrences were identified. Three deaths occurred in the series; 2 patients died with no evidence of disease and 1 patient died of metastatic disease (the nephrectomy was palliative). In the open group, the average operating room time was 117.8 minutes, average length of stay 5.1 days, average time to return to normal activity 23.5 days, and average time to return to work 52.2 days. The median time to return to 100% normal was 150 days, with 3 patients never returning to 100% normal. CONCLUSIONS: Our series demonstrated that HALRN is a safe, effective, minimally invasive option for treating renal cell carcinoma and provides a shorter hospital stay (P = 0.02), earlier return to work (P = 0.04), and earlier return to 100% normal (P = 0.0002) than open radical nephrectomy.

Prospective randomized trial comparing shock wave lithotripsy and ureteroscopy for management of distal ureteral calculi.

PURPOSE: We compared the efficacy of shock wave lithotripsy and ureteroscopy for treatment of distal ureteral calculi. MATERIALS AND METHODS: A total of 64 patients with solitary, radiopaque distal ureteral calculi 15 mm. or less in largest diameter were randomized to treatment with shock wave lithotripsy (32) using an HM3 lithotriptor (Dornier MedTech, Kennesaw, Georgia) or ureteroscopy (32). Patient and stone characteristics, treatment parameters, clinical outcomes, patient satisfaction and cost were assessed for each group. RESULTS: The 2 groups were comparable in regard to patient age, sex, body mass index, stone size, degree of hydronephrosis and time to treatment. Procedural and operating room times were statistically significantly shorter for the shock wave lithotripsy compared to the ureteroscopy group (34 and 72 versus 65 and 97 minutes, respectively). In addition, 94% of patients who underwent shock wave lithotripsy versus 75% who underwent ureteroscopy were discharged home the day of procedure. At a mean followup of 21 and 24 days for shock wave lithotripsy and ureteroscopy, respectively, 91% of patients in each group had undergone imaging with a plain abdominal radiograph, and all studies showed resolution of the target stone. Minor complications occurred in 9% and 25% of the shock wave lithotripsy and ureteroscopy groups, respectively (p value was not significant). No ureteral perforation or stricture occurred in the ureteroscopy group. Postoperative flank pain and dysuria were more severe in the ureteroscopy than shock wave lithotripsy group, although the differences were not statistically significant. Patient satisfaction was high, including 94% for shock wave lithotripsy and 87% for ureteroscopy (p value not significant). Cost favored ureteroscopy by $1,255 if outpatient treatment for both modalities was assumed. CONCLUSIONS: Ureteroscopy and shock wave lithotripsy were associated with high success and low complication rates. However, shock wave lithotripsy required significantly less operating time, was more often performed on an outpatient basis, and showed a trend towards less flank pain and dysuria, fewer complications and quicker convalescence. Patient satisfaction was uniformly high in both groups. Although ureteroscopy and shock wave lithotripsy are highly effective for treatment of distal ureteral stones, we believe that HM3 shock wave lithotripsy, albeit slightly more costly, is preferable to manipulation with ureteroscopy since it is equally efficacious, more efficient and less morbid.

In vitro contractile effects of neurokinin receptor blockade in the human ureter.

PURPOSE: We identified the predominance of neurokinin-2 receptors and evaluated the inhibition of spontaneous contraction via the blockade of neurokinin-2 receptors in human ureteral segments. MATERIALS AND METHODS: Excess ureteral segments from human subjects undergoing donor nephrectomy or reconstructive procedures were suspended in tissue baths containing Krebs buffer. After spontaneous contractions were recorded, tissues were incubated with 1 microM. solutions of phosphoramidon and captopril (to inhibit peptide degradation) and either the neurokinin-1 receptor antagonist CP 99,994, the neurokinin-2 receptor antagonist SR 48,968, the neurokinin-3 receptor antagonist SR 142,801 or dimethyl sulfoxide (control) for 1 hour. Contraction magnitude and frequency were again recorded and compared with spontaneous levels. Concentration-response curves to the tachykinins substance P, and neurokinins A and B were determined in the presence and absence of antagonists. RESULTS: Neurokinin A increased contractility at lower concentrations than substance P or neurokinin B (p <0.013). Neurokinin-2 receptor blockade produced a 100-fold rightward shift of the concentration-response curves (p <0.013), while neurokinins 1 and 3 receptor blockade had no effect. SR 48,968 significantly reduced contractility during the 1-hour incubation period, causing a 97% reduction in spontaneous rates compared with a 29% reduction in control tissues. CP 99,994 and SR 142,801 had no significant effect. CONCLUSIONS: Neurokinin-2 is the predominant receptor subtype responsible for tachykinin induced contraction of human ureteral smooth muscle. In vitro treatment with the neurokinin-2 antagonist SR 48,968 reduces the spontaneous contraction rate by 97% in vitro. Neurokinin-2 receptor antagonists may have clinical applications for ureteral disease.

Future developments and perspectives in laparoscopy.

INTRODUCTION: As urologists head into the new millennium, it has become clear that laparoscopy will play a significant role in successful urologic practice. Issues that are addressed in this article include: (1) What are the new limits? (2) Technological advances. (3) Adequate training. (4) How to technically simplify the laparoscopic procedures? MATERIALS AND METHODS: To answer the stated questions a review of the literature has been undertaken together with interviews of the leading experts and laparoscopic working groups in urologic laparoscopy. The gathered information has been summarized and focussed with the aim of presenting the perspectives of laparoscopy in urology. RESULTS AND DISCUSSION: Standardized indications for laparoscopic urological surgery are benign nephrectomy, nephroureterectomy, cryptorchidism, adrenalectomy, renal cysts, lymphocele and bilateral or relapsing varicocele. Future indications might include living donor nephrectomy, partial nephrectomy and cyst decortication for adult polycystic kidney disease. Controversy exists about the laparoscopic treatment of malignancies in the urinary tract. Whereas pelvic lymph node dissection--even if performed with decreasing frequency--is accepted worldwide, retroperitoneal lymphadenectomy for low-stage testis cancer is currently performed only at few centers. The recent breakthrough in uro-oncological laparoscopic surgery has been laparoscopic radical prostatectomy changing our views on the limits of laparoscopic urology. Endoscopic suturing devices (i.e. Endostitch) are further being developed, and a prototype reapproximating micro-clips (VCS stapler) has been used to perform a uretero-ureterostomy laparoscopically in a porcine model. Nevertheless, the ability of endoscopic suturing using the standard equipment has still to be considered as a "conditio sine qua non". Improvements for tissue division and dissection include an electrosurgical snare to perform a partial nephrectomy, the development of a pneumodissector and hydrodissector. Robotics, including the AESOP 3000 and ZEUS represent a glimpse of the future. By positioning the optique in a voice-controlled full range motion mechanic arm, the image on the screen is very steady and the ergonomics of the surgeons is increased significantly. The da Vinci-System, however, is the first system that has translated all visions of telepresence surgery into clinical reality, recently also for laparoscopic radical prostatectomy. CONCLUSIONS: The future of laparoscopic urology is a two-tiered approach. On the first tier, the advancement of complex reconstructive and ablative surgery such as laparoscopic prostatectomy or, laparoscopic retroperitoneal node dissection, will be undertaken by referral centers of expertise. It is from these individuals that we will look to in order to separate what is feasible and what is reasonable. The second tier will be focusing on simplifying the procedure for the average urologist. As such, developments such as the pneumodissector, hydrodissection, and hand assistance will bring exstirpative laparoscopy into the realm of more urologists. What is critical is that the urologic community supports both groups of laparoscopists.

Cryosurgery and needle ablation of renal lesions.

Laparoscopic renal cryoablation is a minimally invasive alternative for treating renal tumors utilizing narrow probes cooled with a compressed gas such as argon or carbon dioxide. At this time, cryotherapy has shown the most promise as an alternative to partial nephrectomy as a nephron-sparing treatment for renal tumors. Radiofrequency ablation employs needle electrodes placed percutaneously directly into renal lesions to deliver energy, creating high temperatures leading to cell death. High-intensity focused ultrasound is a noninvasive technique in which focused ultrasound energy is applied to cause cell death within the focal zone. Microwave thermotherapy uses small applicators to deliver microwave energy to tissues, resulting in the generation of heat. Although RF, HIFU, and microwave thermotherapy show promise as energy sources for tumor ablation, they are in the early stages of development. Little is known about their acute and chronic histologic effects and long-term efficacy as a treatment for malignant disease. Further work is needed to develop cryosurgery and needle ablation in order to delineate what role these techniques will ultimately play in the management of RCC.

Hand-assisted laparoscopic partial nephrectomy.

BACKGROUND AND PURPOSE: The indications for partial nephrectomy are expanding as newer and more complete data come forth. A partial nephrectomy has traditionally required a generous flank incision. We report our experience using hand-assisted laparoscopy (HAL) as a less-invasive approach to partial nephrectomies. PATIENTS AND METHODS: Between October 1999 and May 2000, we performed 11 HAL partial nephrectomies. The average age of the patients was 55.7 years, the average body mass index was 25.6, and the average ASA class was 2.2. The indications for partial nephrectomy were enhancing solid renal lesions (N = 9) and nonfunctioning renal moiety in a duplicated system (N = 2). In the majority of cases, access to the renal pedicle was obtained prior to the partial nephrectomy. However, in no case did the renal artery or vein require occlusion. Several excisional techniques were employed, but all relied heavily on the Harmonic Scalpel in conjunction with the argon beam coagulator. Different hemostatic agents were applied to the renal defect, including Surgicel, Avitene, and fibrin-soaked Gelfoam activated by thrombin. In several instances, pledget reinforced sutures were placed in the renal capsule to aid with hemostasis. RESULTS: The average operative time was 273 minutes, the estimated blood loss 319 mL, and the change in hematocrit 7.3 points. No patient required a transfusion, and there was one conversion to open. Postoperatively patients, required an average of 35.6 mg of morphine sulfate equivalent and 8.2 narcotic tablets, resumed oral intake in 1.7 days, and were discharged home in 3.3 days. There were no major complications and only two minor complications. Postoperatively, five lesions were found to be benign, four lesions were confirmed to be malignant, and two lesions were consistent with a nonfunctioning duplicated renal moiety. Specimen size averaged 180 cc, and the tumor diameter averaged 1.9 cm. There were no positive surgical margins. CONCLUSIONS: Hand-assisted laparoscopic partial nephrectomy is feasible and reproducible. The surgeon's hand in the operative field facilitates dissection, vascular control, hemostasis, and suturing. Further long-term and prospective studies are underway.

Hand-assisted laparoscopic renal surgery.

The introduction of hand-assisted laparoscopic surgery (HALS) adds another dimension to standard laparoscopy, and particularly benefits the urologic laparoscopist who performs laparoscopic renal procedures. Hand assistance shortens the initial learning curve for laparoscopic nephrectomy and creates alternatives for more experienced laparoscopists. HALS can be performed on any kidney suitable for intact removal, and is well suited to laparoscopic donor nephrectomy, radical nephroureterectomy, and radical nephrectomy with intact removal. The authors' technique, early experience, and indications for hand assistance are described in detail.

Ureteropelvic junction obstruction. Retrograde endopyelotomy.

The modern day treatment of UPJO with retrograde endopyelotomy continues to evolve as experience and knowledge progress. Use of the straight lateral incision and selective use of spiral CT angiogram has refined treatment decisions with retrograde endopyelotomy further. The authors' decision-oriented approach offers guidelines for the practicing urologist. Ultimately, it is up to the urologist and the patient to select the best approach for each clinical scenario.

Determination of stone composition by noncontrast spiral computed tomography in the clinical setting.

OBJECTIVES: Several investigators have evaluated noncontrast computed tomography (NCCT) in predicting stone composition in vitro. We assessed NCCT in predicting stone composition in patients presenting to our emergency room with flank pain and stone disease. METHODS: One hundred twenty-nine patients presenting to our university hospital with flank pain underwent renal colic protocol NCCT scans at the request of the emergency room physicians. A General Electric, high-speed advantage CT scanner was used at 120 kV, 200 mA, and 1.4:1 pitch, with collimation varying between 3 and 5 mm. Ninety-nine patients with predominantly (greater than 50%) calcium oxalate or uric acid composition after either stone passage or stone removal were identified. Each scan was analyzed by one of two radiologists, who determined the predominant attenuation for each stone. Stones once passed or retrieved were analyzed by Urocor Laboratories. The attenuation and attenuation/size ratio (peak attenuation/size in millimeters) were compared with the results of the stone analysis. RESULTS: Eighty-two calculi predominantly composed of calcium oxalate and 17 calculi predominantly composed of uric acid were identified in 99 patients. The calculi ranged in size from 1 to 28 mm. A significant difference (P = 0.017, unpaired t test) was found between the Hounsfield measurement of uric acid calculi (mean 344 +/- 152 HU) and the Hounsfield measurement of calcium oxalate calculi (mean 652 +/- 490 HU). If only the Hounsfield units from stones 4 mm or larger were compared, the data were even more compelling (P = 0.002). However, using an attenuation/size ratio cutoff of greater than 80, the negative predictive value was 99% that a stone would be predominantly calcium oxalate. CONCLUSIONS: Using peak attenuation measurements and the attenuation/size ratio of urinary calculi from NCCT, we were able to differentiate between uric acid and calcium oxalate stones.

Survey of neuromuscular injuries to the patient and surgeon during urologic laparoscopic surgery.

OBJECTIVES: Laparoscopy may be complicated by neuromuscular injuries, both to the patient and to the surgeon. We used a survey to estimate the incidence of these injuries during urologic laparoscopic surgery, to assess risk factors for these injuries, and to determine preventive measures. METHODS: A survey of neuromuscular injuries associated with laparoscopy submitted to 18 institutions in the United States was completed by 18 attending urologists from 15 institutions. RESULTS: From among a total of 1651 procedures, there were 46 neuromuscular injuries in 45 patients (2.7%), including abdominal wall neuralgia (14), extremity sensory deficit (12), extremity motor deficit (8), clinical rhabdomyolysis (6), shoulder contusion (4), and back spasm (2). Neuromuscular injuries were twice as common with upper retroperitoneal as with pelvic laparoscopy (3. 1% versus 1.5%). Among patients with neuromuscular injuries, those with rhabdomyolysis were heavier (means 91 versus 80 kg) and underwent longer procedures (means 379 versus 300 minutes), and those with motor deficits were older (means 51 versus 42 years of age). Of the surgeons, 28% and 17% reported frequent neck and shoulder pain, respectively. CONCLUSIONS: Although not common, neuromuscular injuries during laparoscopy do contribute to morbidity. Abdominal wall neuralgias, injuries to peripheral nerves, and joint or back injuries likely occur no more frequently than during open surgery, but risk of rhabdomyolysis may be increased. Positioning in a partial rather than full flank position may reduce the incidence of some injuries. Measures to reduce neuromuscular strain on the surgeon during laparoscopy should be considered.

Distribution of neuropeptides, histamine content, and inflammatory cells in the ureter.

OBJECTIVES: To determine the anatomic distribution of select neuropeptides (neurokinin A [NKA], substance P [SP], and bradykinin [BK]), of inflammatory cells (leukocytes and mast cells), and the histamine content in the normal swine ureter and compare the findings with regions of increased ureteral contractility. METHODS: Ureters from 10 pigs were obtained and cut into eight segments, proximally to distally. A portion of each ureteral segment was suspended in Krebs buffer (37 degrees C) and attached to force displacement transducers, and spontaneous contractility was measured for 30 minutes. A second portion was assayed for histamine, NKA, SP, and BK using enzyme-linked immunosorbent assay. A third portion was fixed in 10% buffered formalin, stained with hematoxylin-eosin, and evaluated histologically. RESULTS: Ureteral contractility was found to be highest in the most proximal and most distal regions of the ureter. Similarly, SP content was three times greater in the proximal ureter and two times greater in the distal ureter than in the midureter (P <0.05, n = 10). The total NKA and BK content were also higher in the proximal and distal ureter than in the midureter. Conversely, the histamine content was consistent throughout the ureter. Moreover, no significant difference in the distribution of inflammatory cells was identified throughout the ureter. CONCLUSIONS: The anatomic distribution of NKA, SP, and BK in the ureter corresponded to regions of increased spontaneous ureteral contractility, more specifically the proximal and distal ureter. Neuropeptides may play a significant role in ureteral contractility and may be a target for pharmacologic mediation during obstruction and stone passage.

Acucise endopyelotomy.

INTRODUCTION: The evolution of minimally invasive therapy for ureteropelvic junction (UPJ) obstruction has culminated with the Acucise endopyelotomy. Antegrade endopyelotomy, laparoscopic pyeloplasty, and ureteroscopic endopyelotomy all offer excellent minimally invasive alternatives to open pyeloplasty, yet still represent more invasive techniques than the Acucise endopyelotomy in treating the obstructed UPJ. TECHNICAL CONSIDERATIONS: The Acucise endopyelotomy is a straightforward, efficacious, and safe procedure in the appropriate patient for treating UPJ obstruction. Under fluoroscopic guidance, the latest version of the Acucise allows the urologist to perform a retrograde pyelogram, position the Acucise catheter, make the incision, and place a ureteral stent, all over a single guide wire. In my experience, this latest technical modification has further simplified the procedure for the practicing urologist. CONCLUSIONS: In 2000, the Acucise endopyelotomy continues to represent an excellent minimally invasive option for all urologists who choose to perform endopyelotomies.

Selective cyclooxygenase-2 inhibitors reduce ureteral contraction in vitro: a better alternative for renal colic?

PURPOSE: To quantitate the effects of a selective cyclooxygenase (COX)-2 inhibitor, NS-398, on porcine and human ureteral contractility in vitro. MATERIALS AND METHODS: This study was performed in 3 distinct groups. In group 1, segments of ureter were obtained from freshly sacrificed domestic swine. Sections were isolated and suspended longitudinally. Twenty-four ureteral segments were treated with either indomethacin (a nonselective COX inhibitor), NS-398 (selective COX-2 inhibitor), or DMSO (control). Spontaneous contractions were then recorded in each group. In group 2, fifteen segments of human ureter were obtained from patients undergoing donor nephrectomy or ureteral reimplantation. Segments were isolated and suspended as above, and treated with either indomethacin, NS-398, or DMSO. In group 3, eighteen sections of human ureter obtained from donor nephrectomy patients were passively sensitized for 20 hours in ragweed allergic donor serum. Ureteral segments were then treated with either indomethacin, NS-398 or DMSO, and then the segments were subsequently exposed to ragweed antigen and contractions were subsequently recorded. RESULTS: In group 1, the average time to 100% inhibition of spontaneous contraction was 48.8 minutes (S.E.M. = 7.9) for indomethacin, 65.7 minutes (S.E.M. 6.7) for NS-398, and beyond 150 minutes for DMSO. The percent reduction was 100% for indomethacin (S.E.M. = 0), 92.5% for NS-398 (S.E.M. 4.9%), and 52.9% for DMSO (s.e.m. = 10.8%). In group 2, the average time to 100% inhibition was 29 minutes (S.E.M. = 10.4) for indomethacin, 21 minutes (S.E.M. 4.8) for NS-398, and beyond 150 minutes for DMSO. The percent reduction was 100% for indomethacin (S.E.M. = 0), 100% (S.E.M. = 0) for NS-398, and 20% (S.E.M. = 12%) for DMSO. In group 3, ragweed sensitized ureters treated with DMSO (control group) contracted an average maximum of 10 times per 5 minutes. Antigen failed to induce contractions of sensitized tissues treated with indomethacin or NS-398. CONCLUSION: A selective COX-2 inhibitor (NS-398) reduces ureteral contractility as effectively as indomethacin (a nonselective COX inhibitor) in both porcine and human ureteral segments in vitro (p <0.05). Selective COX-2 inhibitors may have significant clinical potential in treating renal colic as they cause less gastric ulceration.