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Purpose: Percutaneous nephrolithotomy (PCNL) has wide variability in the methods of renal access. In many centers, this is done as a separate nephrostomy procedure by interventional radiology, while other urologists gain initial access themselves during the PCNL. We aimed to characterize these trends to confirm the need for continued training in this aspect of PCNL. Methods: Using MarketScan insurance claims, we examined surgical volume for ureteroscopy (URS), extracorporeal shockwave lithotripsy (SWL), and PCNL during 2007-2017. For PCNL, current procedural terminology (CPT) codes were used to identify the provider performing the de novo renal access over time. We stratified postoperative outcomes for PCNL by provider type. Results: From 2007 to 2017, the annual proportion of PCNL procedures peaked at 4.5%, with a recent decline in 2016 and 2017 to 3.2%. URS steadily increased from 46.3% to 60.0% of procedures, and SWL mirrored that change with a decrease from 50.0% to 36.7%. Within 19,743 PCNLs, there was a notable increase from 12.8% to 32.3% in the number of procedures with urologists performing de novo renal access. Most cases (40.0%) still had a de novo access code assigned to a radiologist. Length-of-stay, readmission, transfusion, and secondary stone procedure rates were higher in the radiologist-gained access PCNLs. Conclusions: URS has surpassed SWL as the most common stone procedure. While the proportion of PCNLs has remained fairly stable over the last decade, urologists obtaining their own de novo access have increased substantially. Continued outreach efforts focused on urologist-obtained access may further increase this proportion and improve outcomes for PCNL.

Background: Ureteral stents are commonly employed after ureteroscopy to treat urinary stone disease, but the devices impose a substantial burden of stent-associated symptoms (SAS), including pain and urinary side effects. The NIDDK (National Institute of Diabetes and Digestive and Kidney Diseases) Urinary Stone Disease Research Network sought to develop greater understanding of SAS causes and severity among individuals treated ureteroscopically for ureteral or renal stones. Materials and Methods: We designed a prospective, observational cohort study comprising adolescents and adults undergoing ureteroscopic intervention for ureteral or renal stones. Participants will undergo detailed symptom assessment using validated questionnaires, a psychosocial assessment, and detailed collection of clinical and operative data. Quantitative sensory testing will be utilized to assess pain sensitization. In addition, a small cohort (∼40 individuals) will participate in semi-structured interviews to develop more granular information regarding their stent symptoms and experience. Biospecimens (blood and urine) will be collected for future research. Results: The Study to Enhance Understanding of sTent-associated Symptoms (STENTS) enrolled its first participant in March 2019 and completed nested qualitative cohort follow-up in August 2019. After a planned pause, enrollment for the main study cohort resumed in September 2019 and is expected to be completed in 2021. Conclusion: STENTS is expected to provide important insights into the mechanisms and risk factors for severe ureteral SAS after ureteroscopy. These insights will generate future investigations to mitigate the burden of SAS among individuals with urinary stone disease.

Objectives To review the literature regarding the epidemiology of stone disease and develop a management algorithm based on current evidence and societal guidelines. Methods A structured literature review was performed to determine highest quality of evidence guiding care for pregnant patients with symptomatic nephrolithiasis. PUBMED and EMBASE databases were searched using terms “pregnancy,” “nephrolithiasis,” or “pregnancy” and “renal colic” alone and in combination with “stone”, “kidney stone,” “ultrasound,” “MRI,” “CT,” “percutaneous nephrostomy,” “ureteral stent,” or “ureteroscopy.” All English-language abstracts were reviewed for relevance and full-length articles were reviewed for content. Articles published prior to 1990 were excluded, and priority for inclusion was given to multi-institutional studies and larger institutional studies, reflecting the highest level of current available evidence and most contemporaneous practice patterns. Results Symptomatic nephrolithiasis affects less than 1% of pregnancies but poses unique diagnostic challenges due to the physiologic changes of pregnancy and risks of ionizing radiation exposure to the fetus. Ultrasound remains the imaging modality of choice. Most patients may be managed non-operatively, but drainage with percutaneous nephrostomy or ureteral stent may be performed if warranted. Growing evidence also supports the safety and efficacy of definitive stone treatment. Conclusions Though rare, symptomatic nephrolithiasis poses significant clinical challenges due to the need to minimize risk for both mother and fetus with diagnostic and therapeutic interventions. A multi-disciplinary approach is paramount, as is shared decision making with the patient at each step of care.

Purpose: To test the effectiveness (Participant A) and tolerability (Participant B) of urinary stone comminution in the first-in-human trial of a new technology, burst-wave lithotripsy (BWL). Materials and Methods: An investigational BWL and ultrasonic propulsion system was used to target a 7-mm kidney stone in the operating room before ureteroscopy (Participant A). The same system was used to target a 7.5 mm ureterovesical junction stone in clinic without anesthesia (Participant B). Results: For Participant A, a ureteroscope inserted after 9 minutes of BWL observed fragmentation of the stone to

Objective: Our goals were to validate stone comminution with an investigational burst wave lithotripsy (BWL) system in patient-relevant conditions and to evaluate the use of ultrasonic propulsion to move a stone or fragments to aid in observing the treatment endpoint. Materials and Methods: The Propulse-1 system, used in clinical trials of ultrasonic propulsion and upgraded for BWL trials, was used to fragment 46 human stones (5–7 mm) in either a 15-mm or 4-mm diameter calix phantom in water at either 50% or 75% dissolved oxygen level. Stones were paired by size and composition, and exposed to 20-cycle, 390-kHz bursts at 6-MPa peak negative pressure (PNP) and 13-Hz pulse repetition frequency (PRF) or 7-MPa PNP and 6.5-Hz PRF. Stones were exposed in 5-minute increments and sieved, with fragments >2 mm weighed and returned for additional treatment. Effectiveness for pairs of conditions was compared statistically within a framework of survival data analysis for interval censored data. Three reviewers blinded to the experimental conditions scored ultrasound imaging videos for degree of fragmentation based on stone response to ultrasonic propulsion. Results: Overall, 89% (41/46) and 70% (32/46) of human stones were fully comminuted within 30 and 10 minutes, respectively. Fragments remained after 30 minutes in 4% (1/28) of calcium oxalate monohydrate stones and 40% (4/10) of brushite stones. There were no statistically significant differences in comminution time between the two output settings (p = 0.44), the two dissolved oxygen levels (p = 0.65), or the two calyx diameters (p = 0.58). Inter-rater correlation on endpoint detection was substantial (Fleiss' kappa = 0.638, p

INTRODUCTION AND OBJECTIVE:Ureteral stents are often employed after ureteroscopy, and thought to impair patient quality of life. Despite this well-known impact, there has been little rigorous quali...

INTRODUCTION AND OBJECTIVE:The feasibility of ultrasonic propulsion and burst wave lithotripsy (BWL) to noninvasively reposition distal ureteral stones to facilitate passage and relieve pain was te...

INTRODUCTION AND OBJECTIVE:We report stone comminution in the first human subjects by burst wave lithotripsy (BWL), which is the transcutaneous application of focused, cyclic ultrasound pulses.METH...

Purpose: Ultrasonic propulsion is an investigative modality to noninvasively image and reposition urinary stones. Our goals were to test safety and effectiveness of new acoustic exposure conditions from a new transducer, and to use simultaneous ureteroscopic and ultrasonic observation to quantify stone repositioning. Materials and Methods: During operation, ultrasonic propulsion was applied transcutaneously, whereas stone targets were visualized ureteroscopically. Exposures were 350 kHz frequency, ≤200 W/cm(2) focal intensity, and ≤3-second bursts per push. Ureteroscope and ultrasound (US) videos were recorded. Video clips with and without stone motion were randomized and scored for motion ≥3 mm by independent reviewers blinded to the exposures. Subjects were followed with telephone calls, imaging, and chart review for adverse events. Results: The investigative treatment was used in 18 subjects and 19 kidneys. A total of 62 stone targets were treated ranging in size from a collection of “dust” to 15 mm. Subjects received an average of 17 ± 14 propulsion bursts (per kidney) for a total average exposure time of 40 ± 40 seconds. Independent reviewers scored at least one stone movement ≥3 mm in 18 of 19 kidneys (95%) from the ureteroscope videos and in 15 of 19 kidneys (79%) from the US videos. This difference was probably because of motion out of the US imaging plane. Treatment repositioned stones in two cases that would have otherwise required basket repositioning. No serious adverse events were observed with the device or procedure. Conclusions: Ultrasonic propulsion was shown to be safe, and it effectively repositioned stones in 95% of kidneys despite positioning and access restrictions caused by working in an operating room on anesthetized subjects.

Purpose: Holmium laser lithotripsy is a common modality used to fragment urinary stones during ureteroscopy. Laser energy deposited during activation produces heat and potentially causes thermal bioeffects. We aimed to characterize laser-induced heating through a computational simulation. Materials and Methods: A finite-element model was developed and used to estimate temperature in the urinary tract. Axisymmetric models of laser lithotripsy in a renal calyx, the renal pelvis, and proximal ureter were created. Heat generation by laser and heat transfer were simulated under different laser powers between 5 and 40 W. Irrigation fluid flow was introduced at rates between 0 and 40 mL/min. The model was validated by comparison with previous in vitro temperature data in a test tube, then used to calculate heating and thermal dose in the three tissue models. Results: Simulated temperature rises agreed well with most in vitro experimental measurements. In tissue models, temperature rises depended strongly on laser power and irrigation rate, and to a lesser extent on location. Injurious temperatures were reached for 5–40 W laser power without irrigation, >10 W with 5 mL/min irrigation, 40 W with 15 mL/min irrigation, and were not found at 40 mL/min irrigation. Tissue injury volumes up to 2.3 cm(3) were calculated from thermal dose. Conclusions: The results suggest a numerical model can accurately simulate the thermal profile of laser lithotripsy. Laser heating is strongly dependent on parameters and may cause a substantial temperature rise in the fluid in the urinary tract and surrounding tissue under clinically relevant conditions.

INTRODUCTION AND OBJECTIVE:Our goals were to validate stone comminution with an investigative clinical burst wave lithotripsy (BWL) system and to evaluate the use of ultrasonic propulsion to move t...

Purpose: Burst wave lithotripsy (BWL) is a new technology in development to fragment urinary stones. Ultrasonic propulsion (UP) is a separate technology under investigation for displacing stones. We measure the effect of propulsion pulses on stone fragmentation from BWL. Materials and Methods: Two artificial stone models (crystalline calcite, BegoStone plaster) and human calcium oxalate monohydrate (COM) stones measuring 5 to 8 mm were subjected to ultrasound exposures in a polyvinyl chloride tissue phantom within a water bath. Stones were exposed to BWL with and without propulsion pulses interleaved for set time intervals depending on stone type. Fragmentation was measured as a fraction of the initial stone mass fragmented to pieces smaller than 2 mm. Results: BegoStone model comminution improved from 6% to 35% (p

We report stone comminution in the first 18 human subjects by burst wave lithotripsy (BWL). Subjects undergoing clinical ureteroscopy (URS) for at least one stone ≤12 mm on computed tomography (CT) are recruited. During the planned URS, either before or after ureteroscope insertion, BWL is administered with a handheld probe for 10 min, and any stone fragmentation and tissue injury are observed. The primary effectiveness outcome is the volume percent comminution of the stone into fragments ≤2 mm, where fragment volume is determined by μCT of basketed fragments or image processing of the URS video using the laser fiber as a size reference. The primary safety outcome is independent, blinded grading of tissue injury from the URS video. Overall, 10 of 22 stones (45%) fragmented completely in 10 min. 64% and 73% were projected to fragment completely in 15 and 40 min, respectively. For reference, shock wave lithotripsy success is about 65% to fragments ≤4 mm in 40 min. Of the other six stones, one was larger than the beamwidth, two were smaller than the wavelength, and the ureteroscope introduced air bubbles around another. Only mild reddening with some hematuria was observed ureteroscopically. [Work supported by NIH-P01-DK04331.]

Burst wave lithotripsy (BWL) is a transcutaneous technique with potential to safely and effectively fragment renal stones. Preclinical investigations of BWL require the assessment of potential renal injury. This study evaluates the capabilities of real-time ultrasound and MRI to detect and evaluate BWL injury that was induced in porcine kidneys.Ten kidneys from five female farm pigs were treated with either a 170 or 335 kHz BWL transducer using variable treatment parameters and monitored in real-time with ultrasound. Eight kidneys were perfusion fixed and scanned with a 3-Tesla MRI scanner (T1-weighted, T2-weighted, and susceptibility-weighted imaging), followed by processing via an established histomorphometric technique for injury quantification. In addition, two kidneys were separately evaluated for histologic characterization of injury quality.Observed B-mode hyperechoes on ultrasound consistent with cavitation predicted the presence of BWL-induced renal injury with a sensitivity and specificity of 100% in comparison to the histomorphometric technique. Similarly, MRI detected renal injury with a sensitivity of 90% and specificity of 100% and was able to identify the scale of lesion volumes. The injuries purposefully generated with BWL were histologically similar to those formed by shock wave lithotripsy.BWL-induced renal injury can be detected with a high degree of sensitivity and specificity by real-time ultrasound and post-treatment ex vivo MRI. No injury occurred in this study without cavitation detected on ultrasound. Such capabilities for injury detection and lesion volume quantification on MRI can be used for preclinical testing of BWL.

Objective To investigate whether the use of a belladonna and opium (B&O) rectal suppository administered immediately before ureteroscopy (URS) and stent placement could reduce stent-related discomfort. Methods A randomized, double-blinded, placebo-controlled study was performed from August 2013 to December 2014. Seventy-one subjects were enrolled and randomized to receive a B&O (15 mg/30 mg) or a placebo suppository after induction of general anesthesia immediately before URS and stent placement. Baseline urinary symptoms were assessed using the American Urological Association Symptom Score (AUASS). The Ureteral Stent Symptom Questionnaire and AUASS were completed on postoperative days (POD) 1, 3, and after stent removal. Analgesic use intraoperatively, in the recovery unit, and at home was recorded. Results Of the 71 subjects, 65 had treatment for ureteral (41%) and renal (61%) calculi, 4 for renal urothelial carcinoma, and 2 were excluded for no stent placed. By POD3, the B&O group reported a higher mean global quality of life (QOL) score ( P = .04), a better mean quality of work score ( P = .05), and less pain with urination ( P = .03). The B&O group reported an improved AUASS QOL when comparing POD1 with post-stent removal ( P = .04). There was no difference in analgesic use among groups ( P = .67). There were no episodes of urinary retention. Age was associated with unplanned emergency visits ( P P = .02) Conclusion B&O suppository administered preoperatively improved QOL measures and reduced urinary-related pain after URS with stent. Younger age was associated with severe stent pain and unplanned hospital visits.

Although reported success rates after pediatric pyeloplasty to correct ureteropelvic junction are high, failure may require intervention. We sought to characterize the incidence and timing of secondary procedures after pediatric pyeloplasty using a national employer based insurance database.Using the MarketScan® database we identified patients 0 to 18 years old who underwent pyeloplasty from 2007 to 2013 with greater than 3 months of postoperative enrollment. Secondary procedures following the index pyeloplasty were identified by CPT codes and classified as stent/drain, endoscopic, pyeloplasty, nephrectomy or transplant. The risk of undergoing a secondary procedure was ascertained using Cox proportional hazards models adjusting for demographic and clinical characteristics.We identified 1,976 patients with a mean ± SD followup of 23.9 ± 19.8 months. Overall 226 children (11.4%) had undergone at least 1 post-pyeloplasty procedure. The first procedure was done within 1 year in 87.2% of patients with a mean postoperative interval of 5.9 ± 11.1 months. Stents/drains, endoscopic procedures and pyeloplasties were noted in 116 (5.9%), 34 (1.7%) and 71 patients (3.1%), respectively. Length of stay was associated with undergoing a secondary procedure. Compared with 2 days or less the HR of 3 to 5 and 6 days or greater was 1.65 and 3.94 (p = 0.001 and0.001, respectively).Following pediatric pyeloplasty 1 of 9 patients undergoes at least 1 secondary procedure with the majority performed within the first year. One of 11 patients undergoes intervention more extensive than placement of a single stent or drain, requiring management strategies that generally signify recurrent or persistent obstruction. Estimates of pyeloplasty success in this national data set are lower than in other published series.

Ultrasonic propulsion is a new technology using focused ultrasound energy applied transcutaneously to reposition kidney stones. We report what are to our knowledge the findings from the first human investigational trial of ultrasonic propulsion toward the applications of expelling small stones and dislodging large obstructing stones.Subjects underwent ultrasonic propulsion while awake without sedation in clinic, or during ureteroscopy while anesthetized. Ultrasound and a pain questionnaire were completed before, during and after propulsion. The primary outcome was to reposition stones in the collecting system. Secondary outcomes included safety, controllable movement of stones and movement of stones less than 5 mm and 5 mm or greater. Adverse events were assessed weekly for 3 weeks.Kidney stones were repositioned in 14 of 15 subjects. Of the 43 targets 28 (65%) showed some level of movement while 13 (30%) were displaced greater than 3 mm to a new location. Discomfort during the procedure was rare, mild, brief and self-limited. Stones were moved in a controlled direction with more than 30 fragments passed by 4 of the 6 subjects who had previously undergone a lithotripsy procedure. The largest stone moved was 10 mm. One patient experienced pain relief during treatment of a large stone at the ureteropelvic junction. In 4 subjects a seemingly large stone was determined to be a cluster of small passable stones after they were moved.Ultrasonic propulsion was able to successfully reposition stones and facilitate the passage of fragments in humans. No adverse events were associated with the investigational procedure.

Purpose: Ultrasound is known to overestimate kidney stone size. We explored measuring the acoustic shadow behind kidney stones combined with different ultrasound imaging modalities to improve stone sizing accuracy.Materials and Methods: A total of 45 calcium oxalate monohydrate stones were imaged in vitro at 3 different depths with the 3 different ultrasound imaging modalities of conventional ray line, spatial compound and harmonic imaging. The width of the stone and the width of the acoustic shadow were measured by 4 operators blinded to the true size of the stone.Results: Average error between the measured and true stone width was 1.4 ± 0.8 mm, 1.7 ± 0.9 mm, 0.9 ± 0.8 mm for ray line, spatial compound and harmonic imaging, respectively. Average error between the shadow width and true stone width was 0.2 ± 0.7 mm, 0.4 ± 0.7 mm and 0.0 ± 0.8 mm for ray line, spatial compound and harmonic imaging, respectively. Sizing error based on the stone width worsened with greater depth (p

To examine hospital-level variation in outcomes following benign urologic surgeries given that hospital-level variation in surgical outcomes can portend quality and appropriateness of care concerns and identify quality improvement opportunities in perioperative care.Using the Washington State Comprehensive Hospital Abstract Reporting System, we identified patients who underwent transurethral resection of the prostate (TURP), percutaneous nephrostolithotomy (PCNL), and pyeloplasty from 2003 to 2008. We classified prolonged postoperative length of stay (LOS) as that exceeding the 75th percentile, and we measured the rate of Agency for Healthcare Quality Patient Safety Indicators, readmissions, and death. We calculated hospital-specific observed-to-expected event rates using random effects multilevel multivariable models adjusted for age and comorbidity.We identified 6699 TURP patients at 54 hospitals, 2541 PCNL patients at 45 hospitals, and 584 pyeloplasty patients at 36 hospitals. Complication rates were highest after PCNL (22.9% prolonged LOS vs 17.3% for TURP and 13.9% for pyeloplasty, P .001; 3.4% 90-day mortality vs 0.6% for TURP and 0% for pyeloplasty). Hospital-level variation was most substantial for LOS after TURP and pyeloplasty (8.1% and 14.3% of variance in prolonged LOS, respectively).Hospital-level variation is common after benign inpatient urologic surgeries and may relate to difference in perioperative provider practice patterns. The morbidity of PCNL in this study was higher than expected and merits further investigation.

INTRODUCTION AND OBJECTIVE:Burst wave lithotripsy (BWL) is a new method to noninvasively fragment stones in the urinary tract with focused ultrasound. This is a case report on the first two human s...

INTRODUCTION AND OBJECTIVE:Percutaneous nephrolithotomy (PCNL) is a technically complex and resource intensive procedure recommended for kidney stones larger than 2cm. There is wide variability in ...

Objective To assess drug reactions (ADRs) encountered by practicing urologists for contrast instilled into the urinary collecting system, and to describe current practice patterns regarding contrast administration into the urinary tract for patients with known contrast allergies. Methods Endourological Society members were e-mailed a web-based survey about their prior experience with contrast-related ADRs and practices for contrast administration into the urinary tract among patients with known intravenous contrast allergies. Chi-squared analysis was used to compare management patterns between patients with established allergies and those without. Results An estimated 2300-2500 e-mails were reached, resulting in an estimated response rate of 6.3%-8%. Over 75% of respondents were fellowship trained. Average time in practice was 16 years, and respondents performed a mean of 6.7 urologic contrast studies per week. Among respondents, 32.6%, 14.7%, and 4.0% had treated at least 1 patient with a mild, moderate, or severe reaction, respectively. Contrast-related ADRs were most commonly associated with retrograde pyelogram (50%). For patients with known contrast allergies, 5.4% pursue additional work-up before administering contrast in the urinary tract. Pretreatment with antihistamine or steroids is used by 24.8% and 23.4%, respectively. When performing retrograde pyelograms for such patients, urologists are more likely to use dilute contrast (P = .003), but otherwise do not significantly alter technique. Conclusion Contrast ADRs are encountered not infrequently among practicing urologists. There is notable practice variation in the management of patients with known contrast allergies, though the overall perceived risk of contrast use in these patients is low, provided good technique is used.

Followup imaging after percutaneous nephrolithotomy serves to detect postoperative complications, residual fragments and silent hydronephrosis. However, the timing and optimal imaging modality remain poorly defined. We describe imaging use patterns after percutaneous nephrolithotomy.In the MarketScan® database we identified patients 17 to 64 years old who underwent percutaneous nephrolithotomy between 2007 and 2014. Imaging modalities were identified by CPT, and ICD-9 and 10 codes, and tracked for 1 year after percutaneous nephrolithotomy. The modalities included computerized tomography, renal ultrasound, abdominal x-ray and intravenous pyelogram. Cumulative longitudinal use patterns were characterized and the association with demographic factors was assessed by the chi-square test.Of the 6,495 patients included in analysis 29% and 15% had undergone no postoperative imaging by 3 and 12 months, respectively. While abdominal x-ray was the most common modality at 3, 6 and 12 months, performed in 46%, 53% and 62% patients, respectively, nearly 50% underwent computerized tomography by 1 year. Of these patients 34% underwent computerized tomography within 3 months, which was done within the first 3 days in 69%. During the study period renal ultrasound use increased by 13% while computerized tomography and abdominal x-ray use remained relatively stable. Female gender, residence in the Northeast, no health maintenance organization status and treatment in a metropolitan statistical area were independently associated with higher rates of renal ultrasound on multivariate analyses (p0.05).Among insured adults national imaging patterns vary following percutaneous nephrolithotomy. Many patients do not receive any followup imaging while approximately half undergo computerized tomography within a year. Imaging patterns may be evolving with the increased use of ultrasound.

Our goal is an office-based, handheld ultrasound system to target, detach, break, and/or expel stones and stone fragments from the urinary collecting system to facilitate natural clearance. Repositioning of stones in humans (maximum 2.5 MPa, and 3-second bursts) and breaking of stones in a porcine model (maximum 50 cycles, 20 Hz repetition, 30 minutes, and 7 MPa peak negative pressure) have been demonstrated using the same 350-kHz probe. Repositioning in humans was conducted during surgery with a ureteroscope in the kidney to film stone movement. Independent video review confirmed stone movements (≥ 3 mm) in 15 of 16 kidneys (94%). No serious or unanticipated adverse events were reported. Experiments of burst wave lithotripsy (BWL) effectiveness on breaking human stones implanted in the porcine bladder and kidney demonstrated fragmentation of 8 of 8 stones on post mortem dissection. A 1-week survival study with the BWL exposures and 10 specific-pathogen-free pigs, showed all findings were within normal limits on clinical pathology, hematology, and urinalysis. These results demonstrate that repositioning of stones with ultrasonic propulsion and breaking of stones with BWL are safe and effective.

The study of diagnostic imaging after procedural intervention for nephrolithiasis is limited. We sought to characterize actual national imaging patterns and longitudinal trends after ureteroscopic or shock wave lithotripsy.We analyzed the MarketScan® database and identified a nationally representative sample of insured, employed patients, 17 to 64 years old who underwent ureteroscopic or shock wave lithotripsy for nephrolithiasis between 2007 and 2014. Patients were excluded from study if they lacked at least 1 year of postoperative database enrollment or underwent a repeat nephrolithiasis procedure of any type within 90 days after the initial procedure. We identified and tracked postoperative imaging modalities by medical billing codes.We identified 101,554 patients treated with ureteroscopy, of whom 55% and 39% underwent no postoperative imaging within 3 and 12 months, respectively. Of the 101,590 patients treated with shock wave lithotripsy 23% and 16% underwent no postoperative imaging within 3 and 12 months, respectively. Abdominal x-ray was the most common imaging modality after either procedure type. Ultrasound use increased with time while computerized tomography decreased. In about 25% of ureteroscopy and shock wave lithotripsy cases at least 1 postoperative computerized tomography was done within a year. Female gender and older age were associated with higher imaging rates. Ultrasound was more commonly performed in the northeast region and in more densely populated areas.A notable portion of patients treated with ureteroscopy and a smaller percent treated with shock wave lithotripsy do not undergo any followup imaging within 1 year. In the majority who undergo imaging abdominal x-ray is done, precluding the ability to screen for hydronephrosis or silent obstruction in almost 75% of patients treated with ureteroscopy.

Objective To use econometric methods to assess comparative overall survival of patients with metastatic renal cell carcinoma (mRCC) managed with initial cytoreductive nephrectomy (CN) vs initial systemic therapy. Randomized data demonstrate improved survival for CN preceding cytokine-based therapy in mRCC. This benefit may be attenuated in the contemporary mRCC era given more effective systemic therapies. Methods Patients over age 65 with mRCC from the Surveillance, Epidemiology, and End Results registries linked with Medicare claims from 2006 to 2011 were categorized by initial treatment. We applied sequential survival analysis methods to assess the association between initial CN and overall survival (OS) including Cox proportional hazards models, propensity scoring, and instrumental variable analysis to account for measured and unmeasured selection bias. Results Of 537 patients analyzed, 190 had initial CN followed by targeted therapy and 347 had initial targeted therapy. Median OS in the initial CN group was 17.4 months (interquartile range 9.8-32.0), compared with 9.2 months (interquartile range 4.3-18.0) for initial targeted therapy. Cox proportional hazards analysis revealed initial CN was associated with improved OS (hazard ratio 0.50, 95% confidence interval [CI] 0.38-0.65). Propensity matching demonstrated a survival advantage for initial CN of 5.8 months (95% CI 1.9-9.7). Accounting for unmeasured confounding with instrumental variable analysis demonstrated a trend toward improved survival with initial CN (hazard ratio 0.29 [95% CI 0.08-1.00]). Conclusion Initial CN is associated with improved survival compared with initial systemic therapy in a contemporary population-based mRCC cohort.

In the first-in-human trial of ultrasonic propulsion, subjects passed collections of residual stone fragments repositioned with a C5-2 probe. Here, effectiveness and safety in moving multiple fragments are compared between the C5-2 and a custom (SC-50) probe that produces a longer focal beam and burst duration.Effectiveness was quantified by the number of stones expelled from a calyx phantom consisting of a 30-mm deep, water-filled well in a block of tissue mimicking material. Each probe was positioned below the phantom to move stones against gravity. Single propulsion bursts of 50 ms or 3 s duration were applied to three separate targets: 10 fragments of 2 different sizes (1-2 and 2-3 mm) and a single 4 × 7 mm human stone. Safety studies consisted of porcine kidneys exposed to an extreme dose of 10-minute burst duration, including a 7-day survival study and acute studies with surgically implanted stones.Although successful in the clinical trial, the shorter focal beam and maximum 50 ms burst duration of the C5-2 probe moved stones, but did not expel any stones from the phantom's 30-mm deep calyx. The results were similar with the SC-50 probe under the same 50 ms burst duration. Longer (3 s) bursts available with the SC-50 probe expelled all stones at both 4.5 and 9.5 cm "skin-to-stone" depths with lower probe heating compared to the C5-2. No abnormal behavior, urine chemistry, serum chemistry, or histological findings were observed within the kidney or surrounding tissues for the 10 min burst duration used in the animal studies.A longer focal beam and burst duration improved expulsion of a stone and multiple stone fragments from a phantom over a broad range of clinically relevant penetration depths and did not cause kidney injury in animal studies.

Although success rates are reported to be high, radiographic followup after pyeloplasty to correct ureteropelvic junction obstruction varies in intensity and modality. We characterized postoperative care after pyeloplasty to identify imaging trends.Using the MarketScan® database we identified patients 17 to 65 years old treated with pyeloplasty from 2007 to 2010. Followup imaging was classified as functional (diuretic renogram or excretory urogram) and nonfunctional (ultrasound, computerized tomography or magnetic resonance imaging). The postoperative period was divided into intervals of less than 6, 6 to 12, 12 to 24, 24 to 36 and greater than 36 months. We excluded from study patients with less than 24 months of postoperative enrollment in MarketScan. Multivariate logistic regression was used to determine associations between demographic variables and imaging utilization patterns.We identified 742 patients with a mean ± SD followup of 36.8 ± 3.7 months, of whom 65% underwent minimally invasive pyeloplasty. Of the patients 12% underwent no postoperative imaging. Within the first 6 months 554 patients (75%) underwent at least 1 imaging study and within the first 12 months 82% underwent at least 1 imaging study, which was most commonly functional. After 12 months 54% of patients underwent any imaging, which was most commonly nonfunctional. At least annual imaging was significantly associated with older age, female gender and longer hospital stay. Secondary procedures were required in 62 patients (8%).After pyeloplasty in adulthood most patients undergo a functional imaging study within 6 months. However, after 1 year only half of patients undergo followup imaging. Variability and insufficient radiological followup may bias the belief of pyeloplasty success.

BACKGROUND The delivery of urologic oncology care is susceptible to regional variation. In the current study, the authors sought to define patterns of care for patients undergoing genitourinary cancer surgery to identify underserved areas for urologic cancer care in Washington State. METHODS The authors accessed the Washington State Comprehensive Hospital Abstract Reporting System from 2003 through 2007. They identified patients undergoing radical prostatectomy, radical cystectomy (RC), partial nephrectomy (PN), radical nephrectomy, and transurethral resection of the prostate (TURP). TURP was included for comparison as a reference procedure indicative of access to urologic care. Hospital service areas (HSAs) are where the majority of local patients are hospitalized; hospital referral regions (HRR) are where most patients receive tertiary care. The authors created multivariate hierarchical logistic regression models to examine patient and HSA characteristics associated with the receipt of urologic oncology care out of the HRR for each procedure. RESULTS Greater than one-half of patients went out of their HRR in 7 HSAs (11%) for radical prostatectomy, 3 HSAs (5%) for radical nephrectomy, 10 HSAs (15%) for PN, and 14 HSAs (22%) for RC. No HSAs had high export rates for TURP. Few patient factors were found to be associated with surgical care out of the HRR. High-export HSAs for PN and RC exhibited lower socioeconomic characteristics than low-export HSAs, adjusting for HSA population, race, and HSA procedure rates for PN and RC. CONCLUSIONS Patients living in areas with lower socioeconomic status have a greater need to travel for complex urologic surgery. Consideration of geographic delineation in the delivery of urologic oncology care may aid in regional quality improvement initiatives. Cancer 2014;120:1565–1571. © 2014 American Cancer Society.

To compare perioperative outcomes after robotic-assisted laparoscopic partial nephrectomy (RALPN) with hilar clamping vs parenchymal clamping.A retrospective, single-institution review of the patients undergoing RALPN with hilar or parenchymal clamping was performed. Associations between perioperative factors and clinicopathologic outcomes were determined using the t test, Fisher's exact test, and multivariate linear regression.In 51 patients undergoing RALPN, 36 (71%) and 15 (29%) were performed with hilar and parenchymal clamping, respectively. Median tumor diameter was 2.8 cm for both groups (range, 1.1-6.1; P = .93). Tumor complexity by nephrometry score was mild (69% vs 80%), moderate (29% vs 20%), and high (2% vs 0%) in the respective groups (P = .65). Operative time was significantly shorter in the parenchymal clamp group (median 245 vs 320 minutes; P.0001). There was no difference in blood loss and need for transfusion. On multivariate analysis, hilar clamping (P.01), higher body mass index (P = .01), and higher complexity tumors (P = .02) were significantly associated with longer operative times. The parenchymal clamp group had better preservation of immediate postoperative glomerular filtration rate (GFR) from baseline to postoperative day 2 (median ΔGFR 0 vs -18 mL/min/1.73 m(2), P = .02). These differences from baseline did not persist (median ΔGFR -6 vs -7 mL/min/1.73 m(2), P = .35) at a median follow-up of 6.6 months. Final pathology determination of malignancy (P = .51) and positive margin rates (P = .26) were similar in both groups.Compared with hilar clamping, selective regional ischemia with the parenchymal clamp for mild-moderately complex tumors is feasible and safe during RALPN. Parenchymal clamping is associated with enhanced immediate preservation of GFR and shorter operative times.

Focused ultrasonic propulsion is a new noninvasive technique designed to move kidney stones and stone fragments out of the urinary collecting system. However, to our knowledge the extent of tissue injury associated with this technique is not known. We quantitated the amount of tissue injury produced by focused ultrasonic propulsion under simulated clinical treatment conditions and under conditions of higher power or continuous duty cycles. We compared those results to extracorporeal shock wave lithotripsy injury.A human calcium oxalate monohydrate stone and/or nickel beads were implanted by ureteroscopy in 3 kidneys of live pigs weighing 45 to 55 kg and repositioned using focused ultrasonic propulsion. Additional pig kidneys were exposed to extracorporeal shock wave lithotripsy level pulse intensity or continuous ultrasound exposure 10 minutes in duration using an ultrasound probe transcutaneously or on the kidney. These kidneys were compared to 6 treated with an unmodified Dornier HM3 lithotripter (Dornier Medical Systems, Kennesaw, Georgia) using 2,400 shocks at 120 shock waves per minute and 24 kV. Histological analysis was performed to assess the volume of hemorrhagic tissue injury created by each technique according to the percent of functional renal volume.Extracorporeal shock wave lithotripsy produced a mean ± SEM lesion of 1.56% ± 0.45% of functional renal volume. Ultrasonic propulsion produced no detectable lesion with simulated clinical treatment. A lesion of 0.46% ± 0.37% or 1.15% ± 0.49% of functional renal volume was produced when excessive treatment parameters were used with the ultrasound probe placed on the kidney.Focused ultrasonic propulsion produced no detectable morphological injury to the renal parenchyma when using clinical treatment parameters but produced injury comparable in size to that of extracorporeal shock wave lithotripsy when using excessive treatment parameters.

Focused ultrasound has the potential to expel small stones or residual stone fragments from the kidney, or move obstructing stones to a nonobstructing location. We evaluated the efficacy and safety of ultrasonic propulsion in a live porcine model.Calcium oxalate monohydrate kidney stones and laboratory model stones (2 to 8 mm) were ureteroscopically implanted in the renal pelvicalyceal system of 12 kidneys in a total of 8 domestic swine. Transcutaneous ultrasonic propulsion was performed using an HDI C5-2 imaging transducer (ATL/Philips, Bothell, Washington) and the Verasonics® diagnostic ultrasound platform. Successful stone relocation was defined as stone movement from the calyx to the renal pelvis, ureteropelvic junction or proximal ureter. Efficacy and procedure time was determined. Three blinded experts evaluated histological injury to the kidney in the control, sham treatment and treatment arms.All 26 stones were observed to move during treatment and 17 (65%) were relocated successfully to the renal pelvis (3), ureteropelvic junction (2) or ureter (12). Average ± SD successful procedure time was 14 ± 8 minutes and a mean of 23 ± 16 ultrasound bursts, each about 1 second in duration, were required. There was no evidence of gross or histological injury to the renal parenchyma in kidneys exposed to 20 bursts (1 second in duration at 33-second intervals) at the same output (2,400 W/cm(2)) used to push stones.Noninvasive transcutaneous ultrasonic propulsion is a safe, effective and time efficient means to relocate calyceal stones to the renal pelvis, ureteropelvic junction or ureter. This technology holds promise as a useful adjunct to surgical management for renal calculi.

Partial nephrectomy (PN) can be technically challenging, especially if performed in a minimally invasive manner. Although ultrasound technology has been shown to have therapeutic capabilities, including tissue ablation and hemostasis, it has not gained clinical use in the PN setting. The purpose of this study is to evaluate the ability of a high-intensity ultrasound clamp to create an ablation plane in the kidney providing hemostasis that could potentially aid in laparoscopic PN.A new instrument was created using a laparoscopic Padron endoscopic exposing retractor. Ultrasound elements were engineered on both sides of the retractor to administer high-intensity ultrasound energy between the two sides of the clamp. This high-intensity focused ultrasound (HIFU) clamp was placed 2 to 2.5 cm from the upper and lower poles of 10 porcine kidneys to evaluate its effectiveness at different levels and duration of energy delivery. PN transection was performed through the distal portion of the clamped margin. Kidneys postintervention and after PN were evaluated and blood loss estimated by weighing gauze placed at the defect. Histologic analysis was performed with hematoxylin and eosin and nicotinamide adenine dinucleotide staining to evaluate for tissue viability and thermal spread.Gross parenchymal changes were seen with obvious demarcation between treated and untreated tissue. Increased ultrasound exposure time (10 vs 5 and 2 min), even at lower power settings, was more effective in causing destruction and necrosis of tissue. Transmural ablation was achieved in three of four renal units after 10 minutes of exposure with significantly less blood loss (2 g vs 30-100 g). Nonviable tissue was confirmed histologically. There was minimal thermal spread outside the clamped margin (1.2-3.2 mm).In this preliminary porcine evaluation, a novel HIFU clamp induced hemostasis and created an ablation plane in the kidney. This technology could serve as a useful adjunct to laparoscopic PN in the future and potentially obviate the need for renal hilar clamping.

with lower SW doses targeted to a specific renal calyx, which would be more applicable to patient treatment. A swine model of metabolic syndrome (MetS) was employed as such pigs produce acidic urine, which may better allow the detection of an acidification defect. METHODS: Adult female Ossabaw pigs were fed a hypercaloric diet to induce obesity and MetS. An upper pole renal calyx was treated with 2000 SWs (n1⁄45) or 4000 SWs (n1⁄47) using the HM3 lithotripter (24 kV, 120 SWs/min). Sixty days after SWL, the pigs were anesthetized for assessment of bilateral renal function including bulk (entire renal unit) urine pH. The urine pH value from the SW-treated (T) kidney of pigs was compared to their corresponding contralateral, nontreated (CNT) kidney urine pH value to assess for an acidification defect. Adult female farm pigs fed a normal chow diet were included in the study to confirm that both kidneys ordinarily produce urine of similar pH (n1⁄410). RESULTS: Both kidneys from untreated farm pigs produced urine with similar pH. MetS pig kidneys produced acidic urine with 2000 SW-treated kidneys producing less acidic urine than CNT kidneys, whereas 4000 SW-treated kidneys had a similar urine pH to CNT kidneys. CONCLUSIONS: Measuring the bulk urine pH difference between SW lithotripsy-treated and nontreated kidneys does not appear to be a reliable method to detect a focal urine acidification defect within the SW-treated kidney.

Ultrasonic propulsion is a novel technique that uses short bursts of focused ultrasonic pulses to reposition stones transcutaneously within the renal collecting system and ureter. The purpose of this review is to discuss the initial testing of effectiveness and safety, directions for refinement of technique and technology, and opinions on clinical application.Preclinical studies with a range of probes, interfaces, and outputs have demonstrated feasibility and consistent safety of ultrasonic propulsion with room for increased outputs and refinement toward specific applications. Ultrasonic propulsion was used painlessly and without adverse events to reposition stones in 14 of 15 human study participants without restrictions on patient size, stone size, or stone location. The initial feasibility study showed applicability in a range of clinically relevant situations, including facilitating passage of residual fragments following ureteroscopy or shock wave lithotripsy, moving a large stone at the ureteropelvic junction with relief of pain, and differentiating large stones from a collection of small fragments.Ultrasonic propulsion shows promise as an office-based system for transcutaneously repositioning kidney stones. Potential applications include facilitating expulsion of residual fragments following ureteroscopy or shock wave lithotripsy, repositioning stones prior to treatment, and repositioning obstructing ureteropelvic junction stones into the kidney to alleviate acute renal colic.

Effective stone comminution during shockwave lithotripsy (SWL) is dependent on precise three-dimensional targeting of the shockwave. Respiratory motion, imprecise targeting or shockwave alignment, and stone movement may compromise treatment efficacy. The purpose of this study was to evaluate the accuracy of shockwave targeting during SWL treatment and the effect of motion from respiration.Ten patients underwent SWL for the treatment of 13 renal stones. Stones were targeted fluoroscopically using a Healthtronics Lithotron (five cases) or Dornier Compact Delta II (five cases) shockwave lithotripter. Shocks were delivered at a rate of 1 to 2 Hz with ramping shockwave energy settings of 14 to 26 kV or level 1 to 5. After the low energy pretreatment and protective pause, a commercial diagnostic ultrasound (US) imaging system was used to record images of the stone during active SWL treatment. Shockwave accuracy, defined as the proportion of shockwaves that resulted in stone motion with shockwave delivery, and respiratory stone motion were determined by two independent observers who reviewed the ultrasonographic videos.Mean age was 51 ± 15 years with 60% men, and mean stone size was 10.5 ± 3.7 mm (range 5-18 mm). A mean of 2675 ± 303 shocks was delivered. Shockwave-induced stone motion was observed with every stone. Accurate targeting of the stone occurred in 60% ± 15% of shockwaves.US imaging during SWL revealed that 40% of shockwaves miss the stone and contribute solely to tissue injury, primarily from movement with respiration. These data support the need for a device to deliver shockwaves only when the stone is in target. US imaging provides real-time assessment of stone targeting and accuracy of shockwave delivery.

Objective To examine state-wide trends in adoption of laparoscopic radical nephrectomy (LRN). Open radical nephrectomy and LRN confer equivalent long-term oncological outcomes, yet LRN usage has not increased analogous to diffusion of laparoscopy in other fields. Material and Methods From the Washington State Comprehensive Hospital Abstract Reporting System, we identified patients who underwent ORN and LRN from 1998 to 2007. Number of LRNs was examined for each hospital state-wide. Length of stay outcomes were examined, and multivariate models were created to examine characteristics of LRN patients and of patients who received care at high-volume LRN hospitals (HiLap). Results The proportion of nephrectomies performed laparoscopically increased 27%. In 1998, 7 hospitals (12%) performed ≥1 LRN compared with 36 hospitals (61%) in 2007. Four HiLap hospitals accounted for 61% of the increase in LRN from 1998-2002, and 36% of the increase overall. Women (OR 1.15, 95% CI 1.00-1.33) and healthier patients (OR 1.52, 95% CI 1.28-1.82 for patients with Charlson 0 vs ≥2) were more likely to undergo LRN. Mean length of stay for nephrectomies was shorter at HiLap hospitals (P = .04 for 1998-2002, P

In animal models, pretreatment with low-energy shock waves and a pause decreased renal injury from shockwave lithotripsy (SWL). This is associated with an increase in perioperative renal resistive index (RI). A perioperative rise is not seen without the protective protocol, which suggests that renal vasoconstriction during SWL plays a role in protecting the kidney from injury. The purpose of our study was to investigate whether there is an increase in renal RI during SWL in humans.Subjects were prospectively recruited from two hospitals. All subjects received an initial 250 shocks at low setting, followed by a 2-minute pause. Treatment power was then increased. Measurements of the renal RI were taken before start of procedure, at 250, after 750, after 1500 shocks, and at the end of the procedure. A linear mixed-effects model was used to compare RIs at the different time points.Fifteen patients were enrolled. Average treatment time was 46 ± 8 minutes. Average RI at pretreatment, after 250, after 750, after 1500 shocks, and post-treatment was 0.67 ± 0.06, 0.69 ± 0.08, 0.71 ± 0.07, 0.73 ± 0.07, and 0.74 ± 0.06, respectively. In adjusted analyses, RI was significantly increased after 750 shocks compared with pretreatment (p = 0.05).Renal RI increases early during SWL in humans with the protective protocol. Monitoring for a rise in RI during SWL is feasible and may provide real-time feedback as to when the kidney is protected.

To improve in vitro lithotripsy models, we investigated the effects of multiple experimental variables on stone fragmentation. We performed timed burst wave lithotripsy (BWL) and shock wave lithotripsy (SWL) exposures in a water tank with the following variable parameters: water gas content (60, 30, and 15% O2), temperature (20 and 37°C), stone holder degree of enclosure (open wire basket, polyvinyl chloride (PVC) open-ended gel, and similar material anatomically accurate artificial kidney), and stone type (Begostone at 2 mixture ratios, calcite, calcium oxalate monohydrate (COM), and uric acid). At least 3 stones were treated for each condition, with fragmentation defined as percent stone mass

The AirSeal™ access system is a novel laparoscopic trocar that uses airflow to create insufflation pressure without the need for a physical seal or valve. By eliminating all valve elements within the lumen of the canula, the port provides a platform that accommodates multiple instruments of any diameter, shape, or combination and is ideally suited for laparoendoscopic single-site surgery (LESS). We present our initial experience with valveless trocars in traditional urologic laparoscopic cases and a porcine LESS nephrectomy series.Nine transperitoneal LESS nephrectomies were performed in a live porcine model using the 27-mm oval valveless trocar. All working instruments were placed through the single port, and the specimen was extracted through the 4-cm port site.All cases were completed without technical or operative complications. The porcine single-port nephrectomy (n=9) was successfully performed in a mean operative time of 24 minutes through the single 27-mm oval trocar. This accommodated a 5-mm laparoscope, multiple 5-mm instruments, the Endo GIA stapler, and the 15-mm Endocatch bag without loss of insufflation pressure. Condensation and smudging of the laparoscope were minimized, improving visualization and efficiency. The system allowed for use of suction without significant loss of insufflation pressure.The initial experience with the AirSeal valveless trocar system in LESS is encouraging. This technology may offer significant benefits over traditional laparoscopic trocars and single -port platforms and appears particularly suited to facilitate LESS.

Our goal is an office-based, handheld ultrasound system to target, detach, break, and/or expel stones and stone fragments from the urinary space to facilitate natural clearance. Repositioning of stones in humans (maximum 2.5 MPa, and 3-second bursts) and breaking of stones in a porcine model (maximum 50 cycles, 20 Hz repetition, 30 minutes, and 7 MPa peak negative pressure) have been demonstrated using the same 350-kHz probe. Repositioning in humans was conducted during surgery with a ureteroscope in the kidney to film stone movement. Independent video review confirmed stone movements (≥ 3 mm) in 14 of 15 kidneys (93%). No serious or unanticipated adverse events were reported. Experiments of burst wave lithotripsy (BWL) effectiveness on breaking human stones implanted in the porcine bladder and kidney demonstrated fragmentation of 4 of 4 stones on post mortem dissection. All clinical pathology, hematology, and urinalysis for a 1-week survival study with the BWL exposures in 10 specific pathogen free pigs were within normal limits. These results demonstrate that repositioning of stones with ultrasonic propulsion and breaking of stones with BWL are safe and effective. [Work supported by NIH P01 DK043881, K01 DK104854, and R44 DK109779.]

Following bladder augmentation, patients are at significant risk for bladder calculi. We present our experience with a minimally invasive treatment approach using endoscopically assisted percutaneous cystolithotomy.A retrospective chart review identified 74 patients who underwent percutaneous cystolithotomy following bladder augmentation between 2002 and 2009. Cystogram was performed to determine the ideal location for percutaneous bladder access and a guidewire was inserted in the bladder through a bile needle. A balloon dilator was used to place a 30Fr sheath. Rigid cystoscopy with a 26Fr nephroscope allowed stone treatment by basketing and ultrasonic lithotripsy. A suprapubic 22Fr catheter was then placed. Patients were seen on postoperative day 14 and abdominal ultrasound was performed. If no significant residual calculi were visualized, the suprapubic tube was removed.Mean +/- SD patient age at operation was 20 +/- 10.7 months (range 4 to 40). Mean +/- SD time between bladder augmentation and percutaneous cystolithotomy was 4.8 +/- 2.05 years. Of the patients 38 (51%) were male and 36 (49%) were female. Mean +/- SD number of stones per patient was 4.6 +/- 7.8 (range 1 to 60). Ultrasonic lithotripsy was performed in 49 cases (66%). In 25 cases (34%) only stone basketing was performed. A total of 70 patients (95%) were stone-free on abdominal plain film at 14 days. Of the procedures 24 (32%) were performed on an outpatient basis and 50 were performed on an inpatient basis with a mean +/- SD hospital stay of 1.3 +/- 2.7 days (range 1 to 21). There were 9 minor complications noted (12%).Endoscopic percutaneous cystolithotomy offers a safe and effective treatment option for bladder calculi in reconstructed bladders and is the preferred method at our institution.

Rhabdomyolysis is a rare cause of acute renal failure following laparoscopic donor nephrectomy. The incidence of rhabdomyolysis is not well known and to our knowledge the amount of creatine kinase elevation resulting in renal damage is unknown. We evaluated the incidence of increased creatine kinase, risk factors for increased creatine kinase and its effect on renal function in a series of patients undergoing hand assisted laparoscopic donor nephrectomy.Serum creatine kinase was prospectively measured in 74 consecutive patients who underwent hand assisted laparoscopic donor nephrectomy. These values were measured daily beginning in the recovery room. Demographic and laboratory data, and surgical parameters were analyzed to determine predictors of increased creatine kinase.Eight of 74 patients (10.8%) had a creatine kinase of 2,500 IU/l or greater and 17 (23%) had a creatine kinase of 1,000 IU/l or greater. Factors associated with a creatine kinase of 2,500 IU/l or greater were operative time (320 vs 275 minutes, p = 0.01) and warm ischemia time (192 vs 138 seconds, p0.01). Operative time remained an independent risk factor on multivariate analysis (p0.05). There was no difference in preoperative or postoperative donor creatinine between patients with or without increased creatine kinase, although there was an increased percent change in creatinine in the increased creatine kinase group (80% vs 59%, p = 0.04).Creatine kinase elevation occurs in a small but significant number of patients. Operative time was an independent risk factor for increased creatine kinase. Although creatine kinase had no significant effect on short-term creatinine, there was an increase in the percent change in donor creatinine. Finally, the long-term significance of increased creatine kinase without clinical symptoms is unknown.

OBJECTIVES To describe our experience with pediatric laparoscopic nephrectomy (LN) and laparoscopic nephroureterectomy (LNU) for giant hydronephrosis. METHODS A retrospective review was conducted of all pediatric patients undergoing a transperitoneal LN or LNU. Five of these patients had giant hydronephrosis in a nonfunctioning kidney. Because of chronic infection and the massive nature of hydronephrosis, the system was internally decompressed with an end-hole stent. Partial decompression provided space in the abdomen for adequate visualization while maintaining enough turgidity to facilitate dissection. RESULTS Three LNs and two LNUs were performed in children with giant hydronephrosis. All cases were completed laparoscopically. Vascular anatomy and/or orientation were anomalous in all cases because of mass effect. Mean patient age was 9 years (range, 3 to 17 years). Average surgery time was 281 minutes (range, 225 to 410 minutes), and mean estimated blood loss was 27 mL (range, 5 to 50 mL). Mean time to oral intake was 6.5 hours (range, 4 to 11 hours). All patients were discharged on postoperative day 3, and there were no major or minor complications. CONCLUSIONS Although pediatric LN and LNU for giant hydronephrosis present unique challenges owing to the large renal volume in a small abdominal cavity, these procedures can be safely performed with careful attention to the altered anatomic relationships.

Multidetector CT angiography (MDCTA) is being used increasingly to evaluate vascular anatomy prior to donor nephrectomy. To improve the ability of MDCTA to predict donor renal anatomy, a novel protocol including four-phase imaging with three-dimensional reconstruction and maximum intensity projections (MIPs) was incorporated into the standard donor evaluation. The purpose of this study was to determine the results of this protocol.Seventy consecutive patients who underwent hand-assisted laparoscopic donor nephrectomy between January 2003 and September 2004 were reviewed. All MDCTA studies were examined initially by a radiologist alone, after which, a second preoperative reading was performed by a radiologist and the operating surgeon together. The two reviews were compared with the operative findings.Using this protocol to detect the total number of renal arteries, veins, and ureters, the sensitivity of the initial radiologist was 97%, 100%, and 96%, respectively. These values increased to 100%, 100%, and 99% when the films were reviewed by a radiologist together with the surgeon who would operate on the donor. The sensitivity, specificity, and accuracy in predicting supernumerary arteries, including early (or =1-cm) arterial branching was 89%, 100%, and 97%, respectively after the single reading but increased to 100%, 100%, and 100% with the combined reading.An MDCTA study with this protocol provides excellent anatomic detail prior to donor nephrectomy. Its ability to predict renal-arterial and ureteral anatomy is enhanced when the films are reviewed simultaneously by a radiologist and the operating surgeon.