Simon Hein

Ultra-mini PCNL versus flexible ureteroscopy: a matched analysis of treatment costs (endoscopes and disposables) in patients with renal stones 10–20 mm

PurposeLatest publications state equal efficacy of a recently introduced new percutaneous technique (“ultra-mini PCNL”, UMP) and flexible ureteroscopy (fURS) in the treatment of medium-size urinary stones. Today we face challenges concerning cost-effectiveness and reduction of in-hospital length of stay. In this retrospective study, we compare clinical outcome parameters and costs of treatment (endoscopes and disposables) of both techniques.MethodsThirty patients treated by UMP at two tertiary university centres were matched to 30 fURS patients from previously recorded databases. Data analysis included operating time, length of stay, stone-free rates (SFR), complications (>Clavien II), ancillary procedures (presurgical ureteral stenting, secondary ureteral stenting or placement of a nephrostomy tube, secondary procedures) and costs for disposable materials and instruments (endoscopes, as calculated per procedure).ResultsWe found no significant differences in operating times (UMP vs. fURS: 121/102xa0min), hospital length of stay (2.3/2.0xa0days), SFR (84/87xa0%) and complications (7/7xa0%). Costs for disposable materials and endoscopes were 656 euro (UMP) and 1,160 euro (fURS) per procedure.ConclusionsUMP and fURS are both safe and effective in the treatment of medium-size urinary stones. Costs for endoscopes and disposable materials are significantly lower in UMP.

Ultra-mini PCNL versus flexible ureteroscopy: a matched analysis of analgesic consumption and treatment-related patient satisfaction in patients with renal stones 10–35 mm

AbstractPurposeTo compare ultra-mini PCNL (UMP) and flexible ureteroscopy (fURS) for the treatment of medium- to large-sized renal stones with a focus on patients’ postsurgical cumulative analgesic consumption and treatment-related satisfaction.MethodsnTwenty-five patients treated by UMP between April 2013 and October 2014 were matched to data of 25 fURS patients from an existing database. Clinical outcome parameters were recorded prospectively. Postoperative analgesic consumption was assessed using the Cumulative Analgesic Consumption Score (CACS), and satisfaction was measured with the Freiburg Index of Patient Satisfaction (FIPS) questionnaire.ResultsPerioperative outcome parameters showed no significant differences except for mean operating times (fURS 98.52xa0min, UMP 130.12xa0min [pxa0=xa00.002]) and hospital stay (fURS 67.2xa0h, UMP 91.5xa0h [pxa0=xa00.04]). Primary stone-free rate was 96xa0% in fURS and 92xa0% in UMP. Complications Clavien grade 2 or 3 occurred in 16xa0% of UMP patients and in 4xa0% of fURS patients. Postsurgical cumulative analgesic consumption was almost identical in both groups with CACSs of 6.96 (0–15) for fURS and 6.8 (0–23) for UMP. Patients’ satisfaction was high in both techniques: FIPS score in fURS 1.67 (1–3) and 1.73 (1–4) in UMP (scale 1–6).ConclusionsTreatment of medium- to large-sized renal stones is safe and highly effective by both UMP and fURS. Moreover, both treatments yield comparable postsurgical analgesic requirements and high patient satisfaction scores. Patient-related factors (anatomical and stone related) and availability of technical equipment and surgical expertise appear to be the most important determining factors in treatment planning.

Endoscopically Determined Stone Clearance Predicts Disease Recurrence Within 5 Years After Retrograde Intrarenal Surgery.

OBJECTIVEnTo assess stone-related events (SREs) requiring retreatment in a series of 100 consecutive patients treated by retrograde intrarenal surgery (RIRS) for renal stones and to evaluate potential risk factors thereof.nnnPATIENTS AND METHODSnThe primary outcome was incidence of SRE (medical or surgical treatment). Secondary outcomes included side of SRE, time to SRE, and late complications. Analysis of potential risk factors included high-risk stone formers (HRSFs), obesity, high stone burden, and lower pole stones. In addition, we evaluated endoscopically determined small residual fragments (SRF) of <1u2009mm (i.e., fragments too small for retrieval) as an independent risk factor.nnnRESULTSnEighty-five of the 99 patients were followed up for a mean of 59 months (31-69), among whom 26 (30.1%) had SRE. Thirty-four of the 85 (40%) patients were HRSFs, 22 of whom experienced SRE (both sides) during follow-up (64.7%, pu2009<u20090.001). Eight of the 17 patients (47.1%) with SRF experienced ipsilateral side SRE compared with 13 (19.1%) of the 68 without SRF (pu2009=u20090.022, hazard ratio 2.823, 95% confidence interval [95% CI] 1.16, 6.85). Risk for ipsilateral SRE was unaffected by the presence of SRF among HRSFs (pu2009=u20090.561). Of low-risk patients with SRF, 33.3% experienced ipsilateral SRE, while those without SRF experienced no ipsilateral SRE (pu2009<u20090.001).nnnCONCLUSIONnEndoscopically determined stone clearance predicts disease recurrence within 5 years after RIRS. Even SRF are an important risk factor for future stone-related (ipsilateral) events; therefore, patients with residual fragments of any size should not be labeled stone free and endoscopic stone treatment should aim at complete stone clearance.

Clinical significance of residual fragments in 2015: impact, detection, and how to avoid them

PurposeResidual fragments are common after stone treatment. Little is known about clinical outcomes relevant to the patient. This comprehensive review of the literature highlights the impact of residual fragments, modes of detection, and treatment strategies to avoid residual fragments in shock wave therapy, ureteroscopy, and percutaneous nephrolithotomy.MethodsA comprehensive review of current literature was performed using PubMed®, MEDLINE®, Embase™, Ovid®, Google Scholar™, and the Cochrane Library. Publications relevant to the subject were retrieved and critically appraised.ResultsResidual fragments after treatment for urinary stones have a significant impact on a patient’s well-being and future course. (Ultra-) low-dose non-contrast computed tomography detects small residuals most reliably. In shock wave lithotripsy, adherence to basic principles helps to improve results. Various techniques and devices facilitate complete stone clearance in conventional and miniaturized percutaneous nephrolithotomy and (flexible) ureteroscopy. Promising new technologies in shock waves, lasers, and robotics (and potentially microrobotics) are on the horizon.ConclusionsResidual fragments are relevant to patients. Contemporary treatment of urolithiasis should aim at complete stone clearance.

Novel Biocompatible Adhesive for Intrarenal Embedding and Endoscopic Removal of Small Residual Fragments after Minimally Invasive Stone Treatment in an Ex Vivo Porcine Kidney Model: Initial Evaluation of a Prototype

PURPOSEnResidual fragments related to endoscopic intracorporeal lithotripsy are a challenging problem. The impact of residual fragments remains a subject of discussion and growing evidence highlights that they have a central role in recurrent stone formation. Therefore, we developed a novel bioadhesive system for intrarenal embedding and retrieval of residual fragments after endoscopic lithotripsy in an exxa0vivo porcine kidney model.nnnMATERIALS AND METHODSnIn a standardized setting 30 human stone fragments 1xa0mm or less were inserted in the lower pole of an exxa0vivo porcine kidney model. We assessed the extraction efficacy of flexible ureteroscopy using the bioadhesive system in 15 preparations and a conventional retrieval basket in 15. Outcomes were compared regarding the endoscopic and macroscopic stone-free rate, and overall time of retrieval.nnnRESULTSnEmbedding and retrieving the residual fragment-bioadhesive complex were feasible in all trial runs. We observed no adverse effects such as adhesions between the adhesive and the renal collecting system or the instruments used. The stone-free rate was 100% and 60% in the bioadhesive and conventional retrieval groups, respectively (p = 0.017). Mean retrieval time was significantly shorter at 10 minutes 33 seconds vs 36 minutes 56 seconds in the bioadhesive group vs the conventional group (p = 0.001).nnnCONCLUSIONSnThis novel method involving adhesive based complete removal of residual fragments from the collecting system has proved to be feasible. Our evaluation in a porcine kidney model revealed that this technology performed well. Further tests, including inpatient studies, are required to thoroughly evaluate the benefit and potential drawbacks of bioadhesive based extraction of residual fragments after intracorporeal lithotripsy.

Stereoscopic (3D) versus monoscopic (2D) laparoscopy: comparative study of performance using advanced HD optical systems in a surgical simulator model

PurposeTo compare task performances of novices and experts using advanced high-definition 3D versus 2D optical systems in a surgical simulator model.MethodsFifty medical students (novices in laparoscopy) were randomly assigned to perform five standardized tasks adopted from the Fundamentals of Laparoscopic Surgery (FLS) curriculum in either a 2D or 3D laparoscopy simulator system. In addition, eight experts performed the same tasks. Task performances were evaluated using a validated scoring system of the SAGES/FLS program. Participants were asked to rate 16 items in a questionnaire.ResultsOverall task performance of novices was significantly better using stereoscopic visualization. Superiority of performances in 3D reached a level of significance for tasks peg transfer and precision cutting. No significant differences were noted in performances of experts when using either 2D or 3D. Overall performances of experts compared to novices were better in both 2D and 3D. Scorings in the questionnaires showed a tendency toward lower scores in the group of novices using 3D.ConclusionsStereoscopic imaging significantly improves performance of laparoscopic phantom tasks of novices. The current study confirms earlier data based on a large number of participants and a standardized task and scoring system. Participants felt more confident and comfortable when using a 3D laparoscopic system. However, the question remains open whether these findings translate into faster and safer operations in a clinical setting.

Ultralow Radiation Exposure During Flexible Ureteroscopy in Patients With Nephrolithiasis—How Far Can We Go?

OBJECTIVEnTo evaluate the feasibility and clinical performance of a novel surgeon technique and protocol targeting ultralow fluoroscopy usage in retrograde intrarenal surgery (RIRS).nnnMATERIALS AND METHODSnAll RIRS procedures between 2009 and 2015 for 10- to 20-mm renal calculi performed by the same 2 experienced urologists were eligible. All procedures were performed using a highly standardized step-by-step RIRS technique. This technique was modified by the ultralow radiation exposure RIRS protocol; herein, as much as possible of the standardized steps were performed without radiation control targeting ultralow fluoroscopy usage. Primary end points were fluoroscopy time and dose area product. Secondary end points were stone-free rate (SFR) and intraoperative complications according to Satava classification. End points were evaluated using scatter plots and linear regression model.nnnRESULTSnOverall, 174 procedures were assessed. Over the study period, fluoroscopy time and dose area product could be reduced from 167.7u2009s/318.4 cGy/cm2 in 2009 to 7.4u2009s/6.4 cGy/cm2 in 2015 (Pu2009<.001). SFR (66.7% in 2009; 100% in 2015) and complications (Satava 1 and 2: 28.5% and 4.8%, respectively) improved Pu2009<.1), and the surgical duration was reduced (91 minutes and 65 minutes, respectively, Pu2009<.001).nnnCONCLUSIONnOur findings revealed a continuous reduction of the amount of radiation used by the implementation of a novel ultralow X-ray usage protocol. SFR, complications, and surgical duration all improved, demonstrating that the novel protocol is as effective as current methods. Exposure to ionizing radiation can be significantly reduced if the presented protocol is followed strictly.

Thermal effects of Ho: YAG laser lithotripsy: real-time evaluation in an in vitro model

PurposeTo evaluate the thermal effect of Ho:YAG laser lithotripsy in a standardized in vitro model via real-time temperature measurement.MethodsOur model comprised a 20xa0ml test tube simulating the renal pelvis that was immersed in a 37xa0°C water bath. Two different laser fibers [FlexiFib (15–45xa0W), RigiFib 1000 (45–100xa0W), LISA laser products OHG, Katlenburg-Lindau, Germany] were placed in the test tube. An Ho:YAG 100xa0W laser was used in all experiments (LISA). Each experiment involved 120xa0s of continuous laser application, and was repeated five times. Different laser settings (high vs. low frequency, high vs. low energy, and long vs. short pulse duration), irrigation rates (0 up to 100xa0ml/min, realized by several pumps), and human calcium oxalate stone samples were analyzed. Temperature data were acquired by a real-time data logger with thermocouples (PICO Technology, Cambridgeshire, UK). Real-time measurements were assessed using MatLab®.ResultsLaser application with no irrigation results in a rapid increase in temperature up to ∆28xa0K, rising to 68xa0°C at 100xa0W. Low irrigation rates yield significantly higher temperature outcomes. Higher irrigation rates result immediately in a lower temperature rise. High irrigation rates of 100xa0ml/min result in a temperature rise of 5xa0K at the highest laser power setting (100xa0W).ConclusionsHo:YAG laser lithotripsy might be safe provided that there is sufficient irrigation. However, high power and low irrigation resulted in potentially tissue-damaging temperatures. Laser devices should, therefore, always be applied in conjunction with continuous, closely monitored irrigation whenever performing Ho:YAG laser lithotripsy.

Level of evidence, sponsorship, conflict of interest policy and commercial impact of PubMed‐listed clinical urolithiasis‐related trials in 2014

To evaluate published trials on urolithiasis regarding level of evidence, type of sponsorship and declared conflicts of interest (COIs), and to elucidate a potential commercial impact.

Combined prostatic urethral lift and remodeling of the prostate and bladder neck: a modified transurethral approach in the treatment of symptomatic lower urinary tract obstruction

PurposeThe aim of the study was to evaluate the feasibility and safety of combining prostatic urethral lift (PUL) and a limited resection of the prostatic middle lobe or bladder neck incision in the treatment of lower urinary tract symptoms (LUTS) secondary to benign prostatic hyperplasia (BPH).MethodsTwenty-eight patients were treated at two tertiary centers and followed prospectively. Patient evaluations included patient characteristics, relief of LUTS symptoms, erectile and ejaculatory function, continence, operative time and adverse events. Patients were followed for a mean of 10.9xa0months.ResultsPatient characteristics were as follows: age 66xa0years (46–85), prostate volume 39.6xa0cc (22–66), preoperative IPSS/AUASI 20 (6–35)/QoL 3.9 (1–6)/peak flow 10.5xa0mL/s (4.0–19)/post-void residual volume (PVR) 123xa0mL (0–500). Mean operating time was 31xa0min (9–55). Postoperative complications were minor except for the surgical retreatment of one patient for blood clot retention (Clavien 3b). One patient required catheterization due to urinary retention. Reduction of symptoms (IPSS −xa059.6%), increase in QoL (+xa049.0%), increase in flow (+xa0111.5%), and reduction of PVR (−xa066.8%) were significant. Antegrade ejaculation was always maintained.ConclusionOur data suggest that a combination of PUL and transurethral surgical techniques is feasible, safe, and effective. This approach may be offered to patients with moderate size prostates including those with unfavorable anatomic conditions for PUL. This procedure is still ‘minimally invasive’ and preserves sexual function. In addition, it may add to a higher functional efficacy compared to PUL alone.Study register numberDRKS00008970.