Renal Access Research Articles

Ultrasound-guided percutaneous nephrolithotomy (PCNL) success rates in patients with elevated body mass index: a comparative study.

Percutaneous nephrolithotomy (PCNL) is considered gold standard treatment of renal stones larger than 20mm. Several studies have shown that ultrasound guidance during this procedure is more effective and safer than fluoroscopy. A higher body mass index (BMI) can make ultrasound-guided renal access more difficult and unsuccessful. We present a prospective analysis and comparison of ultrasound-guided PCNL in patients with normal and increased body mass index. We performed a prospective comparison of patients who underwent ultrasound-guided PCNL to remove renal stones by a single surgeon between 2020 and 2022. Patients with BMIs greater than 30 (mean 33.87-obese) were compared to those with BMIs less than 30 (mean 25.69-non-obese). Demographic, perioperative, and follow-up data were collected, analyzed, and included in this study. Total of 98 consecutive patients, with 49 patients in each group were analyzed. No statistically significant differences were observed in terms of stone volume (P = 0.085), stone density (P = 0.5590), location of renal access (P = 0.108), surgery duration (P = 0.38), blood loss (P = 0.54), or laboratory changes after surgery (P = 0.60). 87.76% of obese patients were stone free per CT scan at follow-up, compared to 73.47% of normal-weight patients (P = 0.1238). According to Clavien-Dindo classification, six patients in the non-obese group experienced grade II (10%) and grade III (2%) complications, as opposed to six patients in the obese group with grade I (2%), grade II (6%), and grade III (2%) complications. There was no significant correlation between body mass index and the success or safety of ultrasound-guided PCNL. Although more challenging, a higher BMI should not be an impediment to performing this approach. This method is safe, with no increased incidence of postoperative complications or compromise in stone-free status postoperatively and can diminish or avoid both patient's and medical team's exposure to ionizing radiation.

Effects of standardized language on remote ultrasound-guided percutaneous nephrolithotomy training: A mixed-methods explorative pilot study

BackgroundRemote teaching of procedural skills has demonstrated equivalence in knowledge acquisition compared to in-person teaching. Variations in terminology for probe and needle movements may serve as a barrier in remote training of ultrasound (US)-guided renal access for percutaneous nephrolithotomy (PCNL). This pilot study investigated the utility of standardized terminology in remote training of US-guided renal access for PCNL. HypothesisStandardization of verbal terminology to describe US probe and needle movement instruction improves remote teaching of US-guided renal access. MethodsFifteen urology residents (PGY1-6) were stratified by year and randomized into two groups. We provided participants with images illustrating US probe and needle movements labeled with predetermined standardized terminology for the intervention group and images without labels for the control group. Both groups were asked to perform US-guided renal access on a training mannequin with a remote faculty educator with (intervention) or without (control) use of standardized movement instructions. Quantitative outcomes included number of attempts and time to achieve access. All trainees completed pre- and post-session surveys and participated in focus groups; authors conducted thematic analysis of focus group transcripts. ResultsDifferences in primary outcomes between groups, including number of attempts and time to achieve access of the renal pole, were not statistically significant. Analysis of focus group interviews revealed that the use of standardized terminology in the setting of remote training can reduce trainee confusion by clarifying ambiguity in educator feedback. DiscussionUse of standardized terminology during remote surgical skills training allows for more effective feedback to trainees.

Laparoscopic resolution of Wünderlich syndrome as a primary treatment

Background: Spontaneous Retroperitoneal Hemorrhage, named Wünderlich Syndrome (WS) is usually managed by emergency surgeons with a conventional laparotomy. The aim is to report a patient with WS successfully treated by a laparoscopic approach avoiding open surgery. Methods: A 50-year-old female was diagnosed with WS hemodynamic instability and flank pain. After a normal CT scan that discarded visceral injuries and stabilized, the patient underwent a laparoscopic renal exploration. Results: Laparoscopic approach was as standard transperitoneal renal access. Fortunately, the hematoma was within Gerota fascia meaning a non-complex surgery. Due to the high R.E.N.A.L. score, it was necessary to complete a radical nephrectomy. Surgical time was 120 minutes without perioperative complications and the renal unit was retrieved using a Pfannenstiel incision. Estimate blood loss was not quantified. Finally, the hospital stay was 24 hrs. Conclusion: Laparoscopic approach could be performed in selected patients with WS especially when are hemodynamic stabilized with no visceral injury associated. Immediately treatment could facilitate the procedure because it avoids adherences or fibrosis due to hematoma. Experience in the laparoscopic approach is necessary.

Efficacy and safety of Kumpe access catheter for pre-percutaneous nephrolithotomy renal access in modified supine percutaneous nephrolithotomy

IntroductionTraditionally, a pigtail catheter (PCN) is placed for preoperative renal access before performing percutaneous nephrolithotomy (PCNL). However, PCN can hamper the passage of the guidewire to the ureter, due to which, access tract can be lost. Therefore, Kumpe Access Catheter (KMP) has been proposed for preoperative renal access before PCNL. In this study, we analyzed the efficacy and safety of KMP for surgical outcomes in modified supine PCNL compared to those in PCN.Materials and methodsFrom July 2017 to December 2020, 232 patients underwent modified supine PCNL at a single tertiary center, of which 151 patients were enrolled in this study after excluding patients who underwent bilateral surgery, multiple punctures, or combined operations. Enrolled patients were divided into two groups according to the type of pre-PCNL nephrostomy catheter used: PCN versus KMP. A pre-PCNL nephrostomy catheter was selected based on the radiologist’s preference. A single surgeon performed all PCNL procedures. Patient characteristics and surgical outcomes, including stone-free rate, operation time, radiation exposure time (RET), and complications, were compared between the two groups.ResultsOf the 151 patients, 53 underwent PCN placement, and 98 underwent KMP placement for pre-PCNL nephrostomy. Patient baseline characteristics were comparable between the two groups, except for the renal stone type and multiplicity. The operation time, stone-free rate, and complication rate were not significantly different between the two groups; however, RET was significantly shorter in the KMP group.ConclusionThe surgical outcomes of KMP placement were comparable to those of PCN and showed shorter RET during modified supine PCNL. Based on our results, we recommend KMP placement for pre-PCNL nephrostomy, particularly for reducing RET during supine PCNL.

Optimizing stone harvesting in miniaturized-PCNL: a critical examination of renal access angles, technology, and the role they play in operative efficiency.

Stone retrieval can be a laborious aspect of percutaneous nephrolithotomy (PCNL). A unique phenomenon of mini-PCNL is the vortex-effect (VE), a hydrodynamic form of stone retrieval. Additionally, the vacuum-assisted sheath (VAS) was recently developed as a new tool for stone extraction. The purpose of our study is to investigate the impact of renal access angle (as a surrogate for patient positioning) on stone retrieval efficiency and compare the efficiency among methods of stone retrieval. A kidney model was filled with 3mm artificial stones. Access to the mid-calyx was obtained using a 15Fr sheath. Stones were retrieved over three minutes at angles of 0°, 25°, and 75° utilizing the VE, VAS, and basket. Stones were weighed for comparison of stones/retraction and stones/minute. Trials were repeated three times at each angle. Renal access angle of 0° was associated with increased stone retrieval for both the VE and VAS (p < 0.05). The VE was the most effective method for stones retrieved per individual retraction at an angle of 0° (p < 0.005), although when analyzed as stones retrieved per minute, the VE and VAS were no longer statistically different (p = 0.08). At 75°, none of the methods were statistically different, regardless if analyzed as stones per retraction or per minute (p = 0.20-0.40). Renal access angle of 0° is more efficient for stone retrieval than a steep upward angle. There is no difference in stone retrieval efficiency between the VE and VAS methods, although both are superior to the basket at lower sheath angles.

Pulmonary hypertension and right-sided heart failure in hemodialysis patients

Background &amp; Objectives: Cardiovascular complications are associated with poor outcomes in patients with End stage renal disease. This study is aimed to evaluate the prevalence of pulmonary hypertension and right side heart failure in hemodialysis patients, trying to decrease these complications by referring them to the cardiologist in order to manage them either by medical or interventional methods. Methods: A cross-sectional study for evaluation the prevalence of pulmonary hypertension and right sided heart failure in hemodialysis patients was carried out in Duhok kidney center in Kurdistan region-Iraq through a duration period of one year from first of February, 2020 to 31st of January, 2021 for 101 patients. Data were collected which included Age, gender, BMI, causes of renal failure and vascular access, and echocardiography was conducted by a cardiologist, he evaluated them by using tricuspid regurgitation jet peak gradient for pulmonary hypertension, and by using tricuspid annulus plane systolic excursion method for evaluation of right ventricular function. Results: In the current study 51 females with melasma. Their ages ranged between (19-46) years, with (59.9%) between (28-38) years. The duration of melasma was from 6 months to 9 years. Thirty-eight of them were married and had pregnancy. Thyroid stimulating hormone levels were high in 22 of them (43.1%), 20 out of 22 cases that was had high levels of thyroid stimulating hormone had dermal type of melasma by Wood’s lamp examination and their p-value was significant (0.001). Conclusion: The prevalence of pulmonary hypertension among patients on hemodialysis in Kurdistan region-Iraq is within the Iraqi and international range studies with low prevalence of right ventricular dysfunction.

V02-08 CREATION AND VALIDATION OF A SIMPLE TRAINING MODEL FOR PERCUTANEOUS RENAL ACCESS

You have accessJournal of UrologyCME1 Apr 2023V02-08 CREATION AND VALIDATION OF A SIMPLE TRAINING MODEL FOR PERCUTANEOUS RENAL ACCESS Ala'a Farkouh, Tyler Humphries, Matthew Buell, Akin S. Amasyali, Alphie Rotinsulu, Rose Leu, Kanha Shete, and D. Duane Baldwin Ala'a FarkouhAla'a Farkouh More articles by this author , Tyler HumphriesTyler Humphries More articles by this author , Matthew BuellMatthew Buell More articles by this author , Akin S. AmasyaliAkin S. Amasyali More articles by this author , Alphie RotinsuluAlphie Rotinsulu More articles by this author , Rose LeuRose Leu More articles by this author , Kanha SheteKanha Shete More articles by this author , and D. Duane BaldwinD. Duane Baldwin More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003232.08AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Establishing renal access remains the most challenging aspect during percutaneous nephrolithotomy. Adequate training of urology residents is essential, as improper access can lead to increased morbidity and potential mortality. The purpose of this video was to demonstrate the design, creation, and validation of a simple training model for renal access. METHODS: Using commercially available software, a mold of the renal parenchyma and collecting system was created from a patient’s CT Urogram and then 3D-printed. A silicone kidney model was created from this mold, giving a coronally bisected right kidney with a calyceal system. This model was embedded in ballistic gelatin, which simulated the surrounding muscles and subcutaneous tissue. The final position of the kidney and surrounding gelatin simulated prone PCNL of the right kidney. A small metal ring was used as the target for renal access and was placed in the upper calyx upon a grid to allow measurement of distance from target. A piece of calcium carbonate was embedded into the gelatin over the upper pole of the kidney and simulated a palpable 12th rib. The entire model was covered with an opaque sheet to simulate skin and fluoroscopy was used to guide renal access. Five urologists and 15 novices took part in establishing renal access following training. The primary endpoint was validation of this training model. Construct validity was evaluated by comparing the distance from the target between urologists and novices using the Mann–Whitney U test. Participants were then asked to fill out a survey about the training model to evaluate its face validity. RESULTS: All 5 urologists successfully entered the ring, corresponding to a 0 mm distance from the target. Of the novices, 67% missed the ring, with an average distance of 3.07 mm from the target (p=0.025). When asked if they felt the model is an accurate representation of the anatomy surrounding renal access, 90% answered yes and 10% were unsure. All felt that working on this model will increase their understanding of obtaining renal access. 75% were extremely likely to recommend it for training. CONCLUSIONS: This video demonstrates design, creation, and validation of a simple training model for renal access. Furthermore, it is simple, inexpensive, does not contaminate, and does not raise ethical concerns. Such models should be widely available for trainees to practice and comprehend the principle of obtaining renal access before their attempt in the operating room. Use of models like this could increase the skill of trainees and subsequently reduce patient morbidity. Source of Funding: None © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e170 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Ala'a Farkouh More articles by this author Tyler Humphries More articles by this author Matthew Buell More articles by this author Akin S. Amasyali More articles by this author Alphie Rotinsulu More articles by this author Rose Leu More articles by this author Kanha Shete More articles by this author D. Duane Baldwin More articles by this author Expand All Advertisement PDF downloadLoading ...

MP35-16 LASER-GUIDED RENAL ACCESS FOR PCNL: A COMPARISON TO CONVENTIONAL RENAL ACCESS

You have accessJournal of UrologyCME1 Apr 2023MP35-16 LASER-GUIDED RENAL ACCESS FOR PCNL: A COMPARISON TO CONVENTIONAL RENAL ACCESS Alphie Rotinsulu, Matthew Buell, Ala'a Farkouh, Akin S. Amasyali, Rose Leu, Kanha Shete, Cliff De Guzman, and D. Duane Baldwin Alphie RotinsuluAlphie Rotinsulu More articles by this author , Matthew BuellMatthew Buell More articles by this author , Ala'a FarkouhAla'a Farkouh More articles by this author , Akin S. AmasyaliAkin S. Amasyali More articles by this author , Rose LeuRose Leu More articles by this author , Kanha SheteKanha Shete More articles by this author , Cliff De GuzmanCliff De Guzman More articles by this author , and D. Duane BaldwinD. Duane Baldwin More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003269.16AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: A variety of techniques exist for gaining renal access during PCNL. Commonly used methods include fluoroscopy and ultrasound guided access. Fluoroscopy exposes patients and staff to radiation, while ultrasound is user dependent and has a steep learning curve. The Direct Alignment Radiation Reduction Technique (DARRT) was developed to utilize the best of both conventional methods while using laser targeting to reduce fluoroscopy use. The purpose of this study was to determine how DARRT compares to conventional fluoroscopy for renal access in clinical practice. METHODS: A retrospective review was performed of all patients undergoing PCNL at a single academic institution from January 2017 to June 2022. Patients with pre-existing nephrostomy tubes used for access, hybrid techniques, and ultrasound-guided access were excluded from analysis. Renal access was categorized into either fluoroscopy or DARRT, and the physician obtaining access was noted. Univariate analysis was performed with the Wilcoxon Rank Sum test and Pearson’s Chi Square test, followed by multivariate analysis with factorial ANOVA; p<0.05 was considered significant. RESULTS: Out of 340 PCNL patients, 245 met inclusion criteria. Baseline patient age, BMI, ASA score, Charleston comorbidity score, and stone density were similar between renal access techniques. Patients in the DARRT group had more partial/full staghorn calculi (84% vs 67%; p=0.003). In 92 (37.6%) cases, fluoroscopy was used for renal access and the other 153 (62.4%) cases used DARRT. In 82% of cases, PCNL was performed by an endourologist, whereas the remainder of the cases were performed by a general urologist. DARRT reduced total median procedural fluoroscopy time from 175.8 s to 14.1 s (p<0.001). Multivariate analysis indicated DARRT is an independent factor for decreasing fluoroscopy time. Stone free rates, length of hospital stay, estimated blood loss, complications, and rates of second look operations remained similar (p>0.05 for all) between renal access methods. CONCLUSIONS: The use of DARRT for renal access reduced fluoroscopy time by 92%, without altering stone-free or complication rates. This method is easily learned and can be combined with other known radiation reduction techniques to protect both patients and surgical staff from unnecessary radiation exposure. Source of Funding: None © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e476 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Alphie Rotinsulu More articles by this author Matthew Buell More articles by this author Ala'a Farkouh More articles by this author Akin S. Amasyali More articles by this author Rose Leu More articles by this author Kanha Shete More articles by this author Cliff De Guzman More articles by this author D. Duane Baldwin More articles by this author Expand All Advertisement PDF downloadLoading ...

MP35-14 A NOVEL PREOPERATIVE SCORING SYSTEM FOR PREDICTING SUCCESSFUL RENAL ACCESS FOR ULTRASOUND-GUIDED PERCUTANEOUS NEPHROLITHOTOMY

You have accessJournal of UrologyCME1 Apr 2023MP35-14 A NOVEL PREOPERATIVE SCORING SYSTEM FOR PREDICTING SUCCESSFUL RENAL ACCESS FOR ULTRASOUND-GUIDED PERCUTANEOUS NEPHROLITHOTOMY Ukrit Rompsaithong, Heiko Yang, Wilson Sui, Rei Unno, David Bayne, Justin Ahn, Marshall Stoller, and Thomas Chi Ukrit RompsaithongUkrit Rompsaithong More articles by this author , Heiko YangHeiko Yang More articles by this author , Wilson SuiWilson Sui More articles by this author , Rei UnnoRei Unno More articles by this author , David BayneDavid Bayne More articles by this author , Justin AhnJustin Ahn More articles by this author , Marshall StollerMarshall Stoller More articles by this author , and Thomas ChiThomas Chi More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003269.14AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Renal access remains a challenging but important step in successful percutaneous nephrolithotomy (PCNL). Understanding factors that predict successful access will help operative planning. With ultrasound guidance for renal access being adopted for widespread clinical practice, this study aimed to develop and validate a novel preoperative scoring system for predicting renal access difficulty for ultrasound-guided PCNL. METHODS: We analyzed consecutive patients undergoing ultrasound-guided PCNL from the Registry for Stones of the Kidney and Ureter (ReSKU) between 2015 and 2022. A risk model was created using a randomized data-splitting approach, using 70% for model development and 30% for model validation. Ultrasound-guided access failure was defined as the inability to puncture the renal calyx of choice using ultrasound-only guidance. To create a multivariate model, the preoperative variables were determined using forward selection and modified according to clinical judgment. The predictive scores were created by weighting the coefficients of each significant factor. The total scores were classified into three risk groups according to the prevalence and the correlation of difficult renal access. The final model was validated. RESULTS: Three hundred renal units were used for model development and 90 for validation. Four significant factors were identified in the final model and scored: body mass index ≥40 kg/m2 (2 points), no/mild hydronephrosis (4 points), staghorn (5 points), and diverticular stone (7 points) (Table 1). The total scores were categorized into low (0-4 points), moderate (5-8 points), and high difficulty (9-18 points), with a failure rate of 4.1%, 15.4%, and 50% in each group, respectively. This scoring system had a sensitivity of 78.1% and specificity of 80.7% in predicting failures over the moderate difficulty cut-point. The area under the receiver-operating characteristic (ROC) curve in the final model and the validation group were 85.5% and 87.7%, respectively. CONCLUSIONS: Our novel scoring system may be an effective screening tool to identify difficult cases for ultrasound-guided access. In these patients, we suggest having backup imaging modalities available for alternate means of achieving access. Source of Funding: None © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e474 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Ukrit Rompsaithong More articles by this author Heiko Yang More articles by this author Wilson Sui More articles by this author Rei Unno More articles by this author David Bayne More articles by this author Justin Ahn More articles by this author Marshall Stoller More articles by this author Thomas Chi More articles by this author Expand All Advertisement PDF downloadLoading ...

PD30-08 EVALUATION OF MIXED REALITY (MR) TECHNOLOGIES FOR REMOTE GUIDANCE DURING ULTRASOUND (US)-GUIDED PERCUTANEOUS RENAL ACCESS SIMULATION: A PROSPECTIVE, RANDOMIZED COMPARATIVE TRIAL

You have accessJournal of UrologyCME1 Apr 2023PD30-08 EVALUATION OF MIXED REALITY (MR) TECHNOLOGIES FOR REMOTE GUIDANCE DURING ULTRASOUND (US)-GUIDED PERCUTANEOUS RENAL ACCESS SIMULATION: A PROSPECTIVE, RANDOMIZED COMPARATIVE TRIAL Aaron Saxton, Lauren Shepard, Tyler Holler, Christopher Wanderling, Nathan Schuler, Austin Lee, and Ahmed Ghazi Aaron SaxtonAaron Saxton More articles by this author , Lauren ShepardLauren Shepard More articles by this author , Tyler HollerTyler Holler More articles by this author , Christopher WanderlingChristopher Wanderling More articles by this author , Nathan SchulerNathan Schuler More articles by this author , Austin LeeAustin Lee More articles by this author , and Ahmed GhaziAhmed Ghazi More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003316.08AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: MR enables the fusion of two world view video streams allowing an overlay of an instructor’s hands into the trainee’s view in real time. We aim to evaluate remote MR training compared to in-person (IP) training using a validated US-guided percutaneous renal access hydrogel simulation model. METHODS: 12 residents with <5 cases were randomized into 2 groups. Anatomy and US-guided percutaneous access (PCA) steps were reviewed by trainees prior to completing a (1) pre-test, (2) training session (either MR or IP), (3) mid-test, (4) crossover training and (5) final post-test. Groups were randomized to MR vs IP training first where faculty guided trainees through PCA on a standard hydrogel model. During MR training faculty guided trainees wearing SMART glasses (Vuzix M4000) that transmitted audio and the merged surgical field (Figure 1a). In all 3 tests trainees independently gained needle access, guidewire passage and serial dilatation of the lower and upper pole. Number of attempts, time and 2 reviewers’ scores of each session using a validated grading tool were collected. Post-training surveys evaluated trainee perceptions. RESULTS: On the pre-test, IP group had a higher average score compared to the MR group (55 vs 38, p=0.02) and less average access attempts (5.4 vs 10.5, p<0.05) with comparable times (484 s vs 401, p=0.18). Comparing pre to mid tests, MR vs IP showed a greater improvement in PCA attempts by 22.9% vs 7.4% (p=0.13), time by 19.5% vs 17.9% (p=0.39) and score by 65% vs 25% (p=0.04). After cross-over training, only MR group improved in PCA attempts (14.9%), time (17%) and score (7%). Comparing pre to post-tests the MR 1st vs IP 1st group showed a greater improvement in PCA time (24% vs 14%, p=0.23) and score (39% vs 16%, p=0.03) (Figure 1b). 66.7% of trainees found MR training to be similar to IP regarding usefulness, clarity, accuracy, timeliness and quantity but only 8.3% preferring MR to IP. Participants reported similar confidence in ability to perform simulated US-guided renal access. CONCLUSIONS: Remote training using MR technology provided comparable learning to IP simulation training. Despite the improved performance and equivalent delivery when using MR technology, trainee perceptions towards remote training remain skeptical. Source of Funding: SAU education grant © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e833 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Aaron Saxton More articles by this author Lauren Shepard More articles by this author Tyler Holler More articles by this author Christopher Wanderling More articles by this author Nathan Schuler More articles by this author Austin Lee More articles by this author Ahmed Ghazi More articles by this author Expand All Advertisement PDF downloadLoading ...

MP26-15 EFFECTIVENESS OF THE VORTEX EFFECT DURING MINI-PCNL: IMPACT OF RENAL ACCESS ANGLE AND SPEED OF NEPHOSCOPE RETRIEVAL MOVEMENTS

You have accessJournal of UrologyCME1 Apr 2023MP26-15 EFFECTIVENESS OF THE VORTEX EFFECT DURING MINI-PCNL: IMPACT OF RENAL ACCESS ANGLE AND SPEED OF NEPHOSCOPE RETRIEVAL MOVEMENTS Willian Ito, Dillon Prokop, Crystal Valadon, Bristol Whiles, Donald Neff, David Duchene, and Wilson Molina Willian ItoWillian Ito More articles by this author , Dillon ProkopDillon Prokop More articles by this author , Crystal ValadonCrystal Valadon More articles by this author , Bristol WhilesBristol Whiles More articles by this author , Donald NeffDonald Neff More articles by this author , David DucheneDavid Duchene More articles by this author , and Wilson MolinaWilson Molina More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003254.15AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: The vortex effect (VE) is widely utilized in mini-percutaneous nephrolithotomy (mini-PCNL), although its physical components are still poorly understood. This study aimed to analyze the influence of different renal access angles (as a surrogate for patient positioning) and nephroscope retrieval speeds on the VE’s efficacy during mini-PCNL. METHODS: A Pexiglas™ (KUS®) model was built based on the dimensions of a 15/16Fr mini-PCNL set (Karl Storz®). The flow rate was continuously provided via an automatic pump and calibrated to achieve hydrodynamic equivalence (12mL/sec) to the real equipment. One experiment consisted of retrieving all 30 stone phantoms (3mm diameter) utilizing only the VE. Cumulative time to retrieve all stones was measured. An accelerometer recorded instant speeds every 0.08s, and 3 experiments were performed at each angle (0°, 45°, and 90°). We classified the effectiveness of the VE in each experiment (Figure 1). A multi-logistic regression model was built utilizing angles and maximum speeds to predict the effectiveness of the VE. RESULTS: Mean cumulative time was 28.1s at 0°, 116.5s at 45°, and 101.4s at 90°(p<0.01). We noted significantly higher average and maximum speeds at 0° in comparison to 45° and 90° (p<0.01); however, differences between 45° and 90° were not statistically significant (Table 1). The model demonstrated a negative association between increasing maximum speed and VE’s effectiveness (OR 2.28, CI 1.25-4.21, p=.007). When controlling for maximum speed, the 0° angle had a 30-fold increased chance of a fully effective VE (OR 30.1, CI 95% 1.14 – 80.1, p=0.04). CONCLUSIONS: Increasing the renal access angle negatively impacts the nephroscope retrieval speeds and the effectiveness of the VE, significantly increasing procedure time at higher sheath angles, as it would be seen in prone positioning. Source of Funding: None. © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e359 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Willian Ito More articles by this author Dillon Prokop More articles by this author Crystal Valadon More articles by this author Bristol Whiles More articles by this author Donald Neff More articles by this author David Duchene More articles by this author Wilson Molina More articles by this author Expand All Advertisement PDF downloadLoading ...

MP09-12 IMMERSIVE VIRTUAL REALITY (IVR) FOR PERCUTANEOUS NEPHROLITHOTOMY: THE MORE YOU KNOW, THE BETTER THE OUTCOME

You have accessJournal of UrologyCME1 Apr 2023MP09-12 IMMERSIVE VIRTUAL REALITY (IVR) FOR PERCUTANEOUS NEPHROLITHOTOMY: THE MORE YOU KNOW, THE BETTER THE OUTCOME Andrei D. Cumpanas, Kalon L. Morgan, Antonio R. H. Gorgen, Allen Rojhani, Rohit Bhatt, Candice Minh Tran, Amanda McCormac, Kelvin Vo, Zachary E. Tano, Sohrab N. Ali, Pengbo Jiang, Roshan M. Patel, Jaime Landman, and Ralph V. Clayman Andrei D. CumpanasAndrei D. Cumpanas More articles by this author , Kalon L. MorganKalon L. Morgan More articles by this author , Antonio R. H. GorgenAntonio R. H. Gorgen More articles by this author , Allen RojhaniAllen Rojhani More articles by this author , Rohit BhattRohit Bhatt More articles by this author , Candice Minh TranCandice Minh Tran More articles by this author , Amanda McCormacAmanda McCormac More articles by this author , Kelvin VoKelvin Vo More articles by this author , Zachary E. TanoZachary E. Tano More articles by this author , Sohrab N. AliSohrab N. Ali More articles by this author , Pengbo JiangPengbo Jiang More articles by this author , Roshan M. PatelRoshan M. Patel More articles by this author , Jaime LandmanJaime Landman More articles by this author , and Ralph V. ClaymanRalph V. Clayman More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003224.12AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Understanding the size of a renal stone, its location and relationship with the collecting system is crucial for a successful percutaneous nephrolithotomy (PCNL). Our objective was to study the impact of preoperative immersive virtual reality (iVR) on surgical planning and outcome. METHODS: Between 2019 and 2022, 125 PCNL patients were randomized into either a CT only group (n=75) or an iVR group (n=50). Pre-operatively, using 3D Slicer software, CT scans were rendered into iVR simulations that allowed the surgeon to visualize and manipulate the relevant anatomical landmarks and to simulate the percutaneous approach to the proposed calyx of entry and the renal stone. Surgeon understanding of the case anatomy after viewing the CT scan and after the iVR experience were compared using a Likert scale questionnaire. Postoperative CT scans using 2-3mm cuts were defined as stone free (i.e., no stones), <2 mm remnants, or <4 mm remnants. Postoperative complications were defined using the Clavien classification. RESULTS: There was a significant increase in stone free and <2 mm remnant rate in the iVR group: 19.7% and 17.24%, respectively (Figure 1). There was a trend towards an increased volume of stone ablated per minute of surgery (p=0.07). Of note, 28% of surgeons changed their calyx of choice for PCNL after viewing the iVR model. In the iVR group, there was a 11% lower rate of postoperative complications (Clavien II-III, p=0.013). Surgeons noted that viewing the iVR model enhanced their understanding of the intra-renal anatomy, stone location, stone size, stone shape, orientation of each stone-bearing calyx, and the optimal calyx for renal access (all p<0.01) (Table 1). CONCLUSIONS: Preoperative visualization of an iVR CT generated model improved the urologists’ understanding of the renal anatomy, impacted the surgical plan and was associated with a statistically significant higher stone clearance rate and a lower incidence of Clavien II and III complications. Source of Funding: None © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e109 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Andrei D. Cumpanas More articles by this author Kalon L. Morgan More articles by this author Antonio R. H. Gorgen More articles by this author Allen Rojhani More articles by this author Rohit Bhatt More articles by this author Candice Minh Tran More articles by this author Amanda McCormac More articles by this author Kelvin Vo More articles by this author Zachary E. Tano More articles by this author Sohrab N. Ali More articles by this author Pengbo Jiang More articles by this author Roshan M. Patel More articles by this author Jaime Landman More articles by this author Ralph V. Clayman More articles by this author Expand All Advertisement PDF downloadLoading ...

MP23-03 ULTRASOUND-GUIDED PERCUTANEOUS NEPHROLITHOTOMY (PCNL) SUCCESS RATES IN PATIENTS WITH ELEVATED BODY MASS INDEX, A COMPARATIVE STUDY

You have accessJournal of UrologyCME1 Apr 2023MP23-03 ULTRASOUND-GUIDED PERCUTANEOUS NEPHROLITHOTOMY (PCNL) SUCCESS RATES IN PATIENTS WITH ELEVATED BODY MASS INDEX, A COMPARATIVE STUDY Dolev Perez, David Dotan, Binyamin Neeman, Boris Chertin, and Ilan Kafka Dolev PerezDolev Perez More articles by this author , David DotanDavid Dotan More articles by this author , Binyamin NeemanBinyamin Neeman More articles by this author , Boris ChertinBoris Chertin More articles by this author , and Ilan KafkaIlan Kafka More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003248.03AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Percutaneous nephrolithotomy (PCNL) is considered the gold standard for the treatment of renal stones larger than 20 mm. Several studies have shown that ultrasound guidance during this procedure is more effective and safer than fluoroscopy. A higher body mass index (BMI) can make ultrasound- guided renal access more difficult and unsuccessful. We present a retrospective analysis and comparison of ultrasound- guided PCNL in patients with normal and increased body mass index. METHODS: We performed a retrospective comparison of patients who underwent ultrasound- guided PCNL to remove renal stones by a single surgeon between 2020 and 2022. Patients with BMIs greater than 30 (mean 33.87-Obese) were compared to those with BMIs less than 30 (mean 25.69-non-Obese). Demographic, preoperative, and follow- up data were collected, analyzed, and included in this study. RESULTS: The study included a total of 98 consecutive patients, with 49 patients in each group. No statistically significant differences were observed in terms of stone volume (p=0.085), stone density (p=0.5590), location of renal access (p=0.108), surgery duration (p=0.38), blood loss (p=0.54), or laboratory changes after surgery (p=0.60). 91.84 precent of obese patients were stone- free per CT scan at follow- up, compared to 77.5 percent of normal- weight patients (p=0.089). According to Clavien Dindo classification, six patients in the non-obese group experienced grade II (10%) and grade III (2%) complications, as opposed to five patients in the obese group with grade I (2%), grade II (6%), and grade III (2%) complications. CONCLUSIONS: There was no significant correlation between body mass index and the or safety of ultrasound- guided PCNL. Although more challenging, a higher BMI should not be an impediment to performing this approach. This method is safe, with no increased incidence of postoperative complications or compromise in stone- free status post- operatively, and can diminish or even avoid both patient's and medical team's exposure to ionizing radiation. Source of Funding: None © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e306 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Dolev Perez More articles by this author David Dotan More articles by this author Binyamin Neeman More articles by this author Boris Chertin More articles by this author Ilan Kafka More articles by this author Expand All Advertisement PDF downloadLoading ...

V02-06 ULTRA-LOW DOSE FLUOROSCOPY DURING PCNL: HOW LOW CAN YOU GO?

You have accessJournal of UrologyCME1 Apr 2023V02-06 ULTRA-LOW DOSE FLUOROSCOPY DURING PCNL: HOW LOW CAN YOU GO? Vance Gentry, Kanha Shete, Ala'a Farkouh, Alphie Rotinsulu, Matthew Buell, Rose Leu, Akin S. Amasyali, Matthew Wilson, Joel Pearson, and D. Duane Baldwin Vance GentryVance Gentry More articles by this author , Kanha SheteKanha Shete More articles by this author , Ala'a FarkouhAla'a Farkouh More articles by this author , Alphie RotinsuluAlphie Rotinsulu More articles by this author , Matthew BuellMatthew Buell More articles by this author , Rose LeuRose Leu More articles by this author , Akin S. AmasyaliAkin S. Amasyali More articles by this author , Matthew WilsonMatthew Wilson More articles by this author , Joel PearsonJoel Pearson More articles by this author , and D. Duane BaldwinD. Duane Baldwin More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000003232.06AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Patients diagnosed with renal stones may be subjected to substantial doses of ionizing radiation during diagnosis, treatment, and follow-up. Physicians and other healthcare workers are also exposed to radiation during procedures, such as percutaneous nephrolithotomy (PCNL). This puts both patients and surgeons at the risk of developing radiation-related deleterious outcomes, like malignancies. The purpose of this video is to demonstrate tips and tricks that can be used to reduce radiation exposure during PCNL. METHODS: In this video, we demonstrate techniques to reduce radiation exposure to both patients and surgeons, in an 86-year-old female with a 2 cm renal pelvic and 8 mm lower pole stones who underwent PCNL at an academic center. These steps include planning for surgery, equipment set-up and calibration, use of personal protective equipment (PPE), use of multiple modalities to guide access into the renal pelvis, omitting fluoroscopy from various steps of the surgery, and a low dose CT for follow-up imaging. RESULTS: This video demonstrates a successful PCNL with a total fluoroscopy time of 5.6 seconds. Radiation reduction was achieved preoperatively by reviewing CT scans before surgery to plan access. Intraoperatively all of the following were employed: using a sterile ultrasound to map out a safe zone, relying on tactile feedback instead of fluoroscopy for retrograde glidewire placement into renal pelvis, use of endoscopic combined intrarenal surgery (ECIRS) for renal access, tract dilation, and sheath placement, appropriate use of lead shielding, using pulsed low-dose fluoroscopy, and using laser to guide percutaneous access into the renal pelvis. Post-operatively, ultra-low-dose 7.5 mAs CT scan was used to check for residual stones. CONCLUSIONS: This video has demonstrated many radiation-reducing techniques to both patient and surgeon, all of which can be easily incorporated into daily practice. By following these techniques, we effectively lowered radiation exposure to half the dose of a KUB. Source of Funding: None © 2023 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 209Issue Supplement 4April 2023Page: e169 Advertisement Copyright & Permissions© 2023 by American Urological Association Education and Research, Inc.MetricsAuthor Information Vance Gentry More articles by this author Kanha Shete More articles by this author Ala'a Farkouh More articles by this author Alphie Rotinsulu More articles by this author Matthew Buell More articles by this author Rose Leu More articles by this author Akin S. Amasyali More articles by this author Matthew Wilson More articles by this author Joel Pearson More articles by this author D. Duane Baldwin More articles by this author Expand All Advertisement PDF downloadLoading ...

Simultaneous Antegrade and Retrograde Endoscopic Management of Complete Short-Segment Ureteroileal Anastomotic Stricture: Technique and Early Outcome

Background: Ureteroileal anastomotic strictures have a prevalence of up to 10%. Although open surgical revision remains the gold standard treatment, endoscopic and robotic approaches are described to reduce morbidity.1 Patients with complete occlusive strictures are usually not considered candidates for endoscopic management. There are limited publications with small number of patients who employed endoscopic management for complete occlusive ureteroileal anastomotic stricture. Objective: The aim of this video is to describe surgical approach in a stepwise manner for endoscopic management of a complete short-segment (<1 cm) ureteroileal anastomotic stricture.2–6 Methods: A 51-year-old woman underwent an anterior pelvic exenteration and ileal conduit followed by adjuvant chemoradiotherapy for cervical cancer management. After 1 year, she underwent nephrostomy tube placement for pyelonephritis associated with a left hydroureteronephrosis. Subsequent antegrade nephrostogram demonstrated a complete ureteroileal anastomotic stricture. The patient was counseled regarding various management options, and she opted for endoscopic management. Under general anesthesia we initially performed a flexible cystoscopy through the ileal conduit and were unable to identify the left ureteroileal anastomotic site. We then dilated percutaneous renal access and placed 13F ultra-mini percutaneous nephrolithotomy sheath in kidney under fluoroscopic guidance. Antegrade simultaneous ureteroscopy and nephrostogram confirmed a short-segment complete stenosis of ureteroileal anastomosis. Using 200 micron holmium laser fiber at 1 J × 10 Hz, we incised the distal blind end of ureter near conduit allowing passage of the ureteroscope in periureteral tissue. We then incised the ileal conduit, allowing antegrade advancement of a guidewire into the conduit. This wire was retrieved cystoscopically through an ileal conduit and secured at the level of stoma. Finally, a 7F/14F endoureterotomy stent was placed followed by nephrostomy tube placement. Results: The patient had an uneventful postoperative recovery and was discharged home the next day with an open nephrostomy tube. After 10 days, we confirmed free drainage of contrast into the conduit without extravasation on antegrade nephrostogram and clamped the nephrostomy tube. We later removed nephrostomy tube at 2 weeks and endoureterotomy stent by office cystoscopy at 6 weeks. At 3-month and 1-year follow-up, the patient remained asymptomatic. A renal ultrasonography revealed residual mild left hydronephrosis and a renal scan showed stable split left renal function of 25% with adequate drainage. Conclusion: Our video provides detailed technical nuisances to novice endourologist for a safe and effective treatment of a complete short-segment ureteroileal anastomotic occlusion with simultaneous antegrade and retrograde endoscopic management. No competing financial interests exist. Authors have received and archived patient consent for video recording/publication in advance of video recording of procedure. Runtime of video: 4 mins 58 secs

Efficacy and Safety of Bedside Removal of Tunnelled Hemodialysis Catheter by Noninterventional Nephrologists among Adult Patients in the King Abdulaziz University Hospital Hemodialysis Centre in Jeddah: A Retrospective Cohort Study.

This study aimed to assess the efficacy and safety of bedside removal of tunnelled hemodialysis catheter (TDC) by noninterventional nephrologists among adult patients. It is a retrospective study that involved 53 patients from March 2020 to February 2022 at the King Abdulaziz University Hospital (KAUH) Hemodialysis Centre in Jeddah, Saudi Arabia. Of the 53 participants, 60.4% were male and 40.6% female, and their mean age was 50.94 ± 18.89 years. The most common comorbidities were hypertension (HTN) in 47 (88.7%), diabetes mellitus (DM) in 24 (45.3%), and DM and HTN together in 23 (43.4%) patients. The most common site of TDC removal was the right internal jugular vein (77.4%). In 84.9% of the cases, the TDC was removed as an inpatient procedure, and in the majority of the cases (64.2%), the TDC was removed by a noninterventional nephrologist. The most common reasons for TDC removal were sepsis or clinical concerns for infection (64.2%) and TDC not needed (20.8%) due to recovery of the renal function or access maturation. Most patients (96.2%) suffered no complications; only one of 34 (%) patients with catheter removal by a noninterventional nephrologist had bleeding, which required more observation and monitoring before discharge on the same day. Our study revealed that the bedside TDC removal was well tolerated with a minimal complication rate.

An Update of In Vivo Application of Artificial Intelligence and Robotics for Percutaneous Nephrolithotripsy: Results from a Systematic Review.

Kidney puncture is a key step in percutaneous nephrolithotomy (PCNL). Ultrasound/fluoroscopic-guided access to the collecting systems is commonly used in PCNL. Performing a puncture is often challenging in kidneys with congenital malformations or complex staghorn stones. We aim to perform a systematic review to examine data on in vivo applications, outcomes, and limitations of using artificial intelligence and robotics for access in PCNL. The literature search was performed on November 2, 2022, using Embase, PubMed, and Google Scholar. Twelve studies were included. 3D in PCNL is useful for image reconstruction but also in 3D printing with definite benefits seen in improving anatomical spatial understanding for preoperative and intraoperative planning. 3D model printing and virtual and mixed reality allow for an enhanced training experience and easier access which seems to translate into a shorter learning curve and better stone-free rate compared to standard puncture. Robotic access improves the accuracy of the puncture for ultrasound- and fluoroscopic-guided access in both supine and prone positions. The potential advantage robotics are using artificial intelligence to do remote access, reduced number of needle punctures, and less radiation exposure during renal access. Artificial intelligence, virtual and mixed reality, and robotics may play a key role in improving PCNL surgery by enhancing all aspects of a successful intervention from entry to exit. There is a gradual adoption of this newer technology into clinical practice but is yet limited to centers with access and the ability to afford this.

Is the Supine Position Suitable for Ultrasound-Guided Percutaneous Nephrolithotomy in Patients with Complex Renal Stones?

Introduction: The aim of the study was to assess the safety and efficacy of ultrasound (US)-guided percutaneous nephrolithotomy (PCNL) for complex renal stones when performed in a modified supine position. Methods: We retrospectively reviewed the charts of patients who underwent PCNL for complex renal stones at our institution between August 2018 and December 2021. During this time, 188 consecutive patients underwent US-guided PCNL in the prone position (P group, n = 129) or in the flank-free modified supine position (S group, n = 59). Patient demographics and intraoperative and postoperative data were analyzed. Results: Successful renal access was achieved in all patients. The baseline demographics were comparable between the two groups. The numbers of renal access were significantly higher (2.1 ± 0.4 vs. 1.2 ± 0.2, p = 0.002), and the operation time was comparable (79.1 ± 14.6 min vs. 96.2 ± 19.6 min, p = 0.06) between the two groups. The postoperative hospital stay was also shorter in the P group (6.2 ± 1.5 d vs. 10.2 ± 1.7 d, p = 0.008). The postoperative hemoglobin loss was similar between the P and S groups (1.7 ± 0.4 g/dL vs. 1.8 ± 0.3 g/dL, p = 0.12). The stone-free rate was significantly lower in the S group (57.5% vs. 82.7%, p < 0.001). There were no embolization or septic complications. Twelve patients (20.3%) in the S group underwent simultaneous or staged retrograde flexible ureteroscopy to remove residual stones. Conclusion: US-guided PCNL in the modified supine position was a safe treatment for complex renal stones. However, the single-session stone clearance rate was not ideal. The supine flank-free position may be unsuitable for US-guided PCNL in patients with complex renal stones according to our preliminary findings.

Which renal access technique for percutaneous nephrolithotomy is more difficult to teach using simulation in surgical training?

Percutaneous nephrolithotomy (PCNL) is a challenging procedure that urology trainees should be familiar with during residency. Simulators, such as the PERC Mentor, allows the development of this competency in a safer, stress-free environment. There are two primary fluoroscopic methods of gaining percutaneous renal access: the triangulation method and the bull's eye method. Our goal was to assess which method is easier to teach novices by using the PERC Mentor simulator. A secondary goal is to assess differences in subjective and objective outcomes. Fifteen simulator and procedure-naive medical trainees were randomized into two groups using a crossover, randomized study design. Participants were provided with written, video, in-person demonstrations and hands-on practice for each technique. They then performed each method and were assessed objectively using the PERC Mentor performance data report and subjectively using the PCNL global rating scale (GRS) scoring system. Statistical analysis was performed using Student's T-test and non-parametric Wilcoxon signed rank test. There was no statistical difference in the outcomes and complication rates between the two methods. The bull's eye method of obtaining percutaneous access was associated with a significant decrease in operative time (91 seconds vs. 128 seconds, p=0.03) and fluoroscopy time (87 seconds vs, 123 seconds, p=0.03) compared to the triangulation method. Teaching of both techniques was equally well-acquired by students. Both techniques had similar outcomes; however, the bull's eye method was associated with less operative and fluoroscopy time when compared to the triangulation method among novices.

Evaluating learning curve for renal access during mini-ECIRS: Robotic-assisted fluoroscopic-guidance vs. ultrasound-guidance

Evaluating learning curve for renal access during mini-ECIRS: Robotic-assisted fluoroscopic-guidance vs. ultrasound-guidance