Reverse Trendelenburg Positioning Minimizes Stone Retropulsion During Ureteroscopic Laser Lithotripsy: A Prospective Randomized Study.

Purpose: Retropulsion of stone fragments during ureteroscopic laser lithotripsy (URSLL) remains a challenge for urologists and is associated with increased operative time and reduced stone-free rate (SFR). In this study, we compared the rate of retropulsion of ureteral stones during URSLL between the standard dorsal lithotomy (SDL) position and dorsal lithotomy position with reverse Trendelenburg (RT). Materials and Methods: Patients with ureteral stones requiring surgical intervention between May 2019 and January 2022 were randomized to undergo URSLL in either SDL or RT positions. The primary outcome of this study was stone retropulsion. Secondary outcomes included retropulsion to the kidney, SFR, operative time, 30-day emergency department visits and complications, and the need for conversion from semirigid to flexible ureteroscope. Differences between groups were evaluated using the chi-square test, Fisher exact test, Kruskal-Wallis test, or t-test. Results: A total of 114 patients were included in the study, with 57 patients in each group. There were no differences between groups in terms of baseline demographics or stone characteristics. Retropulsion was significantly less frequent in the RT group (68.4% vs 10.5%, p < 0.01). Similarly, the RT group was favored for lower risk of retropulsion into the kidney (40.4% vs 5.3%, p < 0.01), operative time (43.5 vs 33.0 minutes, p = 0.02), and need for ureteroscope conversion (16.7% vs 2.2%, p = 0.04). There was no difference in the SFR (100% vs 95%, p = 0.49). Conclusions: RT positioning during URSLL for ureteral stones significantly decreases the rate of stone retropulsion, operative time, and the need for conversion from semirigid to flexible ureteroscope.

Displacement of Lower Pole Stones During Retrograde Intrarenal Surgery Improves Stone-free Status: A Prospective Randomized Controlled Trial.

PURPOSE: Lower pole renal stones are associated with the lowest stone-free status of any location in the urinary tract during retrograde intrarenal surgery. Prior work has suggested displacing lower pole stones to a more accessible part of the kidney to improve stone-free status. We sought to prospectively compare the efficacy of laser lithotripsy in situ vs after displacement during retrograde intrarenal surgery for lower pole stones. MATERIALS AND METHODS: Between July 2017 and May 2022 patients undergoing retrograde intrarenal surgery for lower pole stones were randomized into an in situ or displacement group. Demographics, comorbidities, and operative parameters were documented. Primary outcome was stone-free status, determined by combination of abdominal x-ray and renal ultrasound at 30-day follow-up. Secondary outcomes included operative time, 30-day complications, emergency department visits, and readmissions. RESULTS: A total of 138 patients (69 per group) were enrolled and analyzed. Baseline characteristics were similar between groups. Stone-free status significantly favored the displacement group over the in situ group (95% vs 74%, P = .003, n=62 in each group). Operative time, total laser energy usage, 30-day complications, and 30-day emergency department visits or hospital readmissions were similar between groups. On multivariate analysis only study group allocation was significantly associated with stone-free status (P = .024). CONCLUSIONS: Basket displacement of lower pole stones results in a significantly higher stone-free status compared to in situ lithotripsy. The technique is simple, atraumatic, and requires no additional equipment costs and little additional operative time, making it a practical tool in the treatment of lower pole stones.

Active Observation of Biochemical Recurrence without Treatment following Radical Prostatectomy: Long-Term Analysis of Outcomes.

Biochemical recurrence (BCR) following radical prostatectomy (RP) is an unreliable predictor of prostate cancer (PC) progression. This study was a retrospective cohort analysis of prospectively collected data (407/1895) of men with BCR at a tertiary referral center. Patients were assessed for active observation (AO) compared with a treatment group (TG) utilizing doubling time (DT) kinetics. Risk assessment was based on the initial DT (>12 vs. <12 months), then based on the DT pattern (changed over time). Those with unstable, rapidly decreasing DTs received treatment. Those with increasing and slowly decreasing DTs prompted observation. The primary outcome was PC mortality, safety, and efficacy of observations based on DT kinetics. The secondary outcome was BCR patients managed with or without treatment. The median follow-up was 7.5 years (IQR 3.9−10.7). The PCSM in TG and AO was 10.7% and 0%, respectively (p < 0.001). The initial DT was >12 months in 73.6% of AO versus 22.6% of TG (p < 0.001). An increasing DT pattern was observed in 71.5% of AO versus 32.7% of TG (p < 0.001). Utilizing the Cleveland Clinic's PCSM nomogram, at 10 years, predicted and observed PCSM was 8.6% and 9.5% (p = 0.78), respectively. In conclusion, one-third of patients with BCR post-RP were managed without treatment using DT kinetics, avoiding treatment-related complications, quality-of-life issues, and expenses.

A prospective randomized study evaluating the necessity of narcotics following ureteroscopy for urinary stone disease.

PURPOSE: To evaluate the efficacy of non-narcotic analgesics and preoperative counseling in managing postoperative pain and narcotic use following ureteroscopic laser lithotripsy (URS). METHODS: Adult patients at a single academic center undergoing URS for nephrourolithiasis were recruited. After informed consent, subjects were randomized into three groups: NARC-15 tablets oxycodone-acetaminophen 5/325 mg (A-OXY), 2. NSAID-15 tablets ibuprofen (IBU) 600 mg, 3. CNSL-15 tablets A-OXY, 15 tablets IBU, and preoperative counseling from the surgeon to avoid narcotic if possible. Patients who did not receive an intraoperative stent were excluded. At the time of stent removal subjects completed the Universal Stent Symptom Questionnaire (USSQ), and a pill count was performed. USSQ pain indices were the primary study endpoint. RESULTS: Of 115 patients enrolled, 104 met the primary endpoint and were included in the analysis. No significant differences were noted in patient demographic, clinical, or operative characteristics. No differences were noted in median USSQ pain indices. The CNSL group used a significantly lower median number of A-OXY pills compared to the NARC group (2.4 vs. 5.4, p = 0.001) and less IBU compared to the NSAID group (3.1 vs. 5.9, p = 0.008). No differences in median total pill count, office calls, medication requests, nor ED visits were noted. CONCLUSION: Our data suggest that patients can achieve equivalent postoperative analgesic satisfaction with non-narcotics compared to opiates following URS. Further, counseling patients on postoperative pain before surgery can reduce the total number of postoperative narcotic and non-narcotic medications taken. We suggest surgeons strongly consider omission of narcotic prescriptions following non-complicated URS.

Prospective Randomized Evaluation of Idiopathic Hyperoxaluria Treatments.

Purpose: Calcium oxalate (CaOx) stone formation is influenced by urinary oxalate excretion. Stone formers with elevated urinary oxalate are commonly prescribed a low-oxalate diet or oral supplementation with vitamin B6 and magnesium to reduce urinary oxalate excretion. This study aims to compare the effects of dietary modification vs supplementation vs a combination of both on urinary oxalate. Materials and Methods: We enrolled patients with a documented history of CaOx stones and newly diagnosed idiopathic hyperoxaluria. Patients were randomized into three treatment groups: low oxalate diet (D), supplementation with 25 mg vitamin B6 and 400 mg magnesium oxide (S), or both low oxalate diet and B6/magnesium supplementation (DS). Baseline and 3-month postintervention 24-hour urine tests were obtained. The primary endpoint was change in 24-hour urinary oxalate (Ox24) at 12 weeks. Secondary endpoints included changes in other 24-hour urine parameters, compliance rates, and adverse effect rates. Results: In total, 164 patients were recruited and 62, 47, and 55 were enrolled into the D, S, and DS groups, respectively. Of these, 99 patients completed the study (56.5% of the D, 72.3% of the S, and 54.6% of the DS groups, respectively). Significant differences were noted in median percent reduction in Ox24 values (-31.1% vs -16.0% vs -23.9%, p = 0.007) in the D, S, and DS groups, respectively. Furthermore, the percentages of patients within each treatment arm who realized a decrease in Ox24 were also found to be significantly different: D = 91.4% vs. S = 67.6% vs DS = 86.7%, p = 0.027. No significant adverse events were observed in any of the study arms. Conclusion: Low oxalate diet is more effective than B6/magnesium supplementation at lowering urinary oxalate in idiopathic hyperoxaluric stone formers. Combination therapy did not produce greater reductions in urinary oxalate than either of the monotherapy arms suggesting it is of little clinical utility. Further study with long-term longitudinal follow-up is required to determine if these treatment strategies reduce recurrent stone events in this population.

Deceived by a CT Scan: The Case of the Misrepresented Stone Size.

Background: CT has become the gold standard for radiographic evaluation of urolithiasis. CT is highly sensitive for detecting kidney stones and provides valuable information regarding stone size, composition, location, and overall stone burden. Although CT can provide reliable estimations of stone size, we have encountered an instance in which it can be deceiving. Motion artifact in CT images can cause a warping distortion effect that makes renal stones appear larger than they actually are. Case Presentation: We describe a case of a 37-year-old woman with a history of kidney stones and obesity presenting with intermittent flank pain and gross hematuria, found to have a large lower pole renal calculus that appeared deceptively large on CT imaging. Given the apparent size and location of the stone, the patient was counseled and consented for a percutaneous nephrolithotomy (PCNL). Although the stone was initially suspected to be >2 cm based on the preoperative CT scan, intraoperative pyelography revealed a much smaller than expected radio-dense stone. The patient was stone free after PCNL without any immediate postoperative complications. However, her course was later complicated by delayed bleeding causing significant clot hematuria, perinephric hematoma, and reactive pleural effusion. Conclusion: Although CT is especially valuable in preparing for surgery based on its ability to outline collecting system anatomy, it is important to remember that it can be deceiving. Correlation with kidney, ureter, and bladder radiograph and ultrasound is critical to understanding the clinical case and planning the optimal surgical approach.

Ultrasound-Guided Totally Tubeless Mini-Percutaneous Nephrolithotomy for a Completely Excluded Caliceal Diverticulum Associated with Challenging Anatomy.

Mini-percutaneous nephrolithotomy (mini-PCNL) has been described as a safe and effective technique to eliminate stones in patients in whom a less-invasive approach is desired. It was originally developed to treat stones in the pediatric population, but has since been adapted to serve a role in the adult urologic community. This approach has been reported to result in less blood loss and postoperative pain when compared with traditional PCNL. Herein, we present a case in which a recurrent caliceal diverticulum containing stones was managed using a mini-PCNL technique in a patient who previously failed multiple other retrograde endoscopic approaches.

Ultrasound-Guided Access in a Malrotated Kidney: Optimally Safe and Effective.

Background: Management of renal calculi in a patient with kidney malrotation can be difficult because of complexity and alteration of collecting system anatomy. Pyelolithotomy, whether open, laparoscopic, or robotic, has been shown to be an effective method of stone removal in this patient population; however, it is not always ideal because of its invasiveness and increased morbidity. Ideally, a percutaneous approach may be less invasive, and if feasible, it can optimize patient safety and stone-free status. Case Presentation: Here we present a case of a 68-year-old Caucasian female who presented with 2.7 cm stone in the renal pelvis of a severely malrotated left kidney, which was managed using a combination of fluoroscopy and ultrasound (US)-guided percutaneous nephrolithotomy. Conclusion: US-guided access properly delineates the anatomic complexities of a severely malrotated kidney and permits safe percutaneous management of large stones. This is because fluoroscopic guidance alone may lead to inadvertent adjacent visceral organ trauma and increased risk of parenchymal and intrarenal vascular injury.

Extravesical Ectopic Ureteral Calculus Obstruction in a Completely Duplicated Collecting System.

Background: Complete ureteral duplication is uncommon and occasionally associated with ureteral stone obstruction. Even rarer is ectopic insertion of a ureter into the urethra. Case Presentation: We describe a case of a 75-year-old man with a history of robot-assisted laparoscopic prostatectomy and complete unilateral duplicated collecting system with a ureteral stone obstructing an ectopic ureter inserting into the urethra. The stone was effectively treated using ureteroscopy with laser lithotripsy. Conclusion: Ectopic ureters can be located in any of the Wolffian duct structures, and can perhaps be relocated iatrogenically secondary to bladder neck reconstruction during a prostatectomy. This should be kept in mind when performing ureteroscopy on this patient population.

Infected Renal Cyst: Elusive Diagnosis and Percutaneous Management.

Background: Benign renal cysts are relatively common in older adults, usually found incidentally on CT. However, an infected renal cyst is a rare complication. While a course of antibiotic therapy is generally the first-line treatment, indications for definitive operative intervention include chronic pain, recurrent urinary tract infection, hematuria, abscess formation, and/or impaired renal function. Case Presentation: A 61-year-old male urologist with no significant medical history was hospitalized at an outside facility for fever, chills, and abdominal pain. Initial diagnosis was pyelonephritis in the setting of a recently passed stone, with absence of hydronephrosis and a large, simple right renal cyst, but he failed to improve with intravenous antibiotics and developed intractable hiccups. Serial CT scans demonstrated onset of mild upper pole hydronephrosis and no change in the benign-appearing simple cyst. Interventional radiology planned drainage of the upper pole calices with a diagnosis of infundibular stenosis, but upon insistence of a urology consultant who suspected occult infection of the cyst, drains were placed into the collecting system and the cyst, with the return of a jet of purulent fluid upon cyst puncture. Conclusion: The patient subsequently recovered and was discharged and seen at our facility where he was definitively treated with percutaneous endoscopic marsupialization of the cyst into the collecting system and fulguration of the infected cyst wall with complete resolution.

Morphometry scores: Clinical implications in the management of staghorn calculi.

Due to their large size, rapid growth, and attendant morbidity, staghorn calculi are complex clinical entities that impose significant treatment-related challenges. Moreover, their relative heterogeneity-in terms of both total stone burden and anatomic distribution-limits the ability to standardize their characterization and the reporting of surgical outcomes. Several morphometry systems currently exist to define the volumetric distribution of renal stones, in general, and to predict the outcomes of percutaneous nephrolithotomy; however, they fall short in their applicability to staghorn stones. In this review, we aim to discuss the clinical utility of morphometry systems and the influence of pelvicalyceal anatomy on the management of these complex calculi.

Peri-Calculus Ureteral Thickness on Computed Tomography Predicts Stone Impaction at Time of Surgery: A Prospective Study.

Introduction and Objectives: Ureteroscopic management of impacted ureteral stones poses multiple challenges. We examined whether ureteral thickness measured on preoperative noncontrast computed tomography (CT) is predictive of stone impaction at the time of ureteroscopy (URS). Methods: Thirty-eight patients with preoperative CT scan and undergoing URS for ureteral stones were prospectively studied. Ureteral thickness directly above, around (peri-calculus ureteral thickness [P-CUT]), and below the calculus were determined on CT scan. The cross-sectional surface area around the stone (P-CUT) was also calculated. Stones were considered impacted at surgery if contrast had difficulty passing, a guidewire could not pass, and the stone was visually impacted >5 on a Likert scale. The surgeon determining intraoperative impaction and the individual measuring the ureteral thickness on CT were blinded. Results: Fourteen of the 38 patients were found to have an impacted ureteral stone at the time of surgery. Patients with an intraoperative finding of an impacted stone had significantly higher ureteral thickness above, around (P-CUT), below the calculus, and P-CUT surface area with all four p-values <0.001. P-CUT surface area was independently predictive of impaction at the time of surgery on multivariate analysis. A mean P-CUT of 6.1 and 1.6 mm and P-CUT surface area of 92.6 and 15.4 mm2 were noted for the impacted and nonimpacted stones, respectively. Conclusion: Ureteral thicknesses above, around (P-CUT), and below the calculus are readily measurable on CT scan. P-CUT surface area can also be calculated for a stronger representation of ureteral thickness. These four parameters are predictive of ureteral stone impaction and useful for surgical planning and patient counseling.

What Factors Drive Staghorn vs Nonstaghorn Pattern Growth in Patients with Metabolic Stones?

Purpose: There has been an increase in the number of staghorn calculi that form in the absence of infection (metabolic staghorns). It is unknown why some large metabolic calculi form as solitary or multiple separate, nonbranching caliceal stones, whereas others develop as staghorn stones forming a cast of the collecting system. We sought to compare these two groups of metabolic stone formers (SFs) in an attempt to shed light on these disparate stone-forming phenomena. Materials and Methods: From January 2017 to September 2018, 190 patients underwent percutaneous nephrolithotomy for stones >2 cm. We identified 86 (45%) patients with a metabolic stone, defined as ≥80% calcium oxalate monohydrate or dihydrate and/or calcium phosphate. Exclusion criteria included stones composed of cystine, >20% uric acid, or any infectious element (struvite or carbonate apatite). Metabolic staghorn and nonstaghorn SFs were compared with respect to medical comorbidity, 24-hour urine parameters, stone and urine microbiology, stone compositions, and intraoperative findings. Statistical differences were assessed using chi-square analysis, Fisher's exact test, and Student's t-test. Results: In total, 25 (29%) staghorn and 61 (71%) nonstaghorn SFs were included for analysis. The groups were statistically similar in age, sex, body mass index, and medical comorbidity. Staghorn SFs had larger stone burdens (p < 0.0001), but did not require more punctures (p = 0.783). Staghorn SFs were more likely to have hyperoxaluria (p = 0.041) and higher mean 24-urine oxalate levels (p = 0.040). There were no other significant differences in 24-hour urine profiles, rates of metabolic abnormalities, stone compositions, stone or urine cultures, presence of collecting system obstruction, or pelvicaliceal anatomy. Conclusions: Although potentially driven by urinary oxalate, whether a metabolic stone will form into a staghorn configuration or not does not appear significantly influenced by standard determinants of stone development, including metabolic profile, cultures, hydronephrosis, and pelvicaliceal anatomy, among others. Further work is needed to elucidate the physicochemical factors that govern the pathogenesis of this increasingly prevalent entity.

Predicting the Impacted Ureteral Stone with Computed Tomography.

OBJECTIVE: To evaluate whether preoperative computed tomography (CT) findings could predict the presence of an impacted stone. Preoperative identification of an impacted ureteral stone may influence patient preparation and operative decisions. Factors predicting ureteral stone impaction have not been clearly identified. METHODS: We identified all patients from June 2014 to July 2016 that underwent ureteroscopic treatment of an impacted ureteral stone. Patients that had ureteral prestenting or previous treatment for their stone were excluded. Noncontrast CT images were reviewed to calculate stone size, stone volume, degree of hydronephrosis (0-3), and Hounsfield units (HU) of the stone as well as the ureter distal and proximal to the stone. These were compared with a control group of patients that had nonimpacted stones. RESULTS: Patients with impacted stones had a greater stone size, volume, HU of the ureter under the stone, HU under/above ratio, and degree of hydronephrosis on univariate analysis. Multivariate analysis demonstrated that HU under the stone was a significant predictor of ureteral stone impaction (odds ratio 1.17; 95% confidence interval 1.11-1.25). Distal ureteral density above 27 HU demonstrated a sensitivity of 85%, specificity of 85%, positive predictive value of 89%, and negative predictive value of 81% for ureteral stone impaction. CONCLUSION: Impacted stones are associated with ureteral density cut-off value of 27 HU or greater. Measuring this value on preoperative noncontrast CT may help predict which patients are more likely to have impacted stones.

A Randomized, Double-Blind, Sham-Controlled Study Assessing Electroacupuncture for the Management of Postoperative Pain after Percutaneous Nephrolithotomy.

INTRODUCTION: Percutaneous nephrolithotomy (PCNL) is the gold standard procedure for large renal calculi but postoperative (PO) pain remains a concern. Modifications of the PCNL technique and intraoperative and PO strategies have been tested to reduce pain. PO pain control reducing risk of long-term pain medication and narcotic use is of considerable importance. Acupuncture is a common medical procedure shown to alleviate PO pain. Some benefits are that it is nonpharmacologic, easy to administer, and safe. The purpose of this study was to evaluate the effects of electroacupuncture (EA) on PO pain in patients undergoing PCNL. MATERIALS AND METHODS: This was a randomized, double-blind, sham-controlled study. The study was Institutional Review Board approved and performed under standard ethical guidelines. Fifty-one patients undergoing PCNL by a single surgeon were randomized to one of the three groups: true EA (n = 17), sham EA (SEA, n = 17), and no acupuncture (control, n = 17). The EA and SEA were performed by a single licensed acupuncturist <1 hour before operation. PCNL was performed without the use of intraoperative nerve block(s) or local anesthetic. Pain scores (visual analog scale [VAS]), narcotic use (morphine equivalents), and side effects were recorded at set intervals postoperatively. RESULTS: Mean VAS scores for flank and abdomen pain were lower at all time periods in the EA compared with the SEA and control groups. Mean cumulative opioid usage was lower in the EA group immediately postoperatively compared with both SEA and control groups. Two patients in the EA group did not require any PO narcotics. No differences between groups were found for PO nausea and vomiting. No adverse effects of EA or SEA were noted. CONCLUSIONS: EA significantly reduced PO pain and narcotic usage without any adverse effects after PCNL. This promising treatment for managing PO pain warrants further investigation.

Cost-Free Laser Caging in the Operating Room.

We have assembled a three-step process for securing and presetting the functional length of the laser fiber to be used for ureteroscopic lithotripsy. For this process, three components are required: a sterile piece of adhesive, an empty guidewire casing with a pre-attached Luer-Lok™ fitting, and a SureSeal® adapter. The only additional piece of equipment for this arrangement not routinely used during ureteroscopy is the sterile adhesive strip.

Transurethral Electrovaporization of Bladder Diverticulum: An Alternative to Open or Laparoscopic Bladder Diverticulectomy.

We used transurethral electrovaporization of the diverticular mucosa as the primary treatment for an acquired bladder diverticulum in a female patient. The bladder diverticulum was secondary to bladder outlet obstruction from a previous pubovaginal sling. In comparison to either open or laparoscopic bladder diverticulectomy, transurethral electrovaporization of the bladder diverticulum was effective in significantly reducing the diverticular size while being less invasive, requiring a short operative time, and a quick patient recovery.

The impact of surgeon choice on the cost of performing laparoscopic appendectomy.

INTRODUCTION: While laparoscopic appendectomy (LA) can be performed using a myriad of techniques, the cost of each method varies. The purpose of this study is to analyze the effects of surgeon choice of technique on the cost of key steps in LA. METHODS: Surgeon operative notes, hospital invoice lists, and surgeon instrumentation preference sheets were obtained for all LA cases in 2008 at Cambridge Health Alliance (CHA). Only cases (N = 89) performed by fulltime staff general surgeons (N = 8) were analyzed. Disposable costs were calculated for the following components of LA: port access, mesoappendix division, and management of the appendiceal stump. The actual cost of each disposable was determined based on the hospital's materials management database. Actual hospital reimbursements for LA in 2008 were obtained for all payers and compared with the disposable cost per case. RESULTS: Disposable cost per case for the three portions analyzed for 126 theoretical models were calculated and found to range from US $81 to US $873. The surgeon with the most cost-effective preferred method (US $299) utilized one multi-use endoscopic clip applier for mesoappendix division, two commercially available pretied loops for management of the appendiceal stump, and three 5-mm trocars as their preferred technique. The surgeon with the least cost-effective preferred method (US $552) utilized two staple firings for mesoappendix division, one staple firing for management of the appendiceal stump, and 12/5/10-mm trocars for access. The two main payers for LA patients were Medicaid and Health Safety Net, whose total hospital reimbursements ranged from US $264 to US $504 and from US $0 to US $545 per case, respectively, for patients discharged on day 1. DISCUSSION: Disposable costs frequently exceeded hospital reimbursements. Currently, there is no scientific literature that clearly illustrates a superior surgical method for performing these portions of LA in routine cases. This study suggests that surgeons should review the cost implications of their practice and to find ways to provide the most cost-effective care without jeopardizing clinical outcome.