Access For Percutaneous Nephrolithotomy Research Articles

Optimizing Colon Identification by Window Setting Modulation on Noncontrast Computed Tomography Prior to Percutaneous Nephrolithotomy.

Background: Preoperative identification of the bowel on imaging is essential in planning renal access during percutaneous nephrolithotomy (PCNL) and avoiding colonic injury. We aimed this study to assess which noncontrast computed tomography (NCCT) window setting provides the optimal colonic identification for PCNL preoperative planning. Methods: Ten urologic surgeons (four seniors, six residents) reviewed 22 images of NCCT scans in both abdomen and lung window settings in a randomized blinded order. Colonic area delineation in each image was performed using a dedicated, commercially available area calculator software. A comparison of the marked colonic area between the abdomen and lung window settings was performed. Results: Overall, the mean marked colonic area was greater in the lung window compared with the abdomen window (8.82 cm2 vs 7.4 cm2, respectively, p < 0.001). Switching the CT window from abdomen to lung increased the identified colonic area in 50 cases (50%). Intraclass correlation showed good agreement between the senior readers and among all readers (0.92 and 0.87, respectively). Similar measurements of the colonic area in both abdomen and lung windows were observed in 26/44 (60%) of the seniors cases and in 7/66 (10%) of the resident cases (p = 0.002). Conclusion: Lung window solely or in combination with abdomen window appears to provide the most accurate colonic identification for preoperative planning of PCNL access and potentially reduce the risk of colonic injury. This pattern is more evident among young urologists, and we propose to introduce it as a standard sequence in PCNL preplanning.

Ultrasound-guided percutaneous nephrolithotomy versus conventional c-arm-guided percutaneous nephrolithotomy: a prospective randomized comparative study

BackgroundUltrasound guidance for renal access in percutaneous nephrolithotomy (PCNL) is a safe, effective, and low-cost procedure. The current study compared the safety and effectiveness of ultrasound-guided PCNL (US-PCNL) for renal stone therapy versus fluoroscopy-guided PCNL (FL-PCNL) in prone position.ResultsSuccessful puncture was attained in all cases in both groups. Unlike fluoroscopy, US guidance reduced the time needed for achieving renal puncture that was (22.45 ± 6.95 s) compared to fluoroscopy that was (68.28 ± 56.76 s) (P value < 0.001). The mean duration of access that was reported in our study was (3.92 ± 0.72 min) in the US-PCNL group and (4.03 ± 0.77 min) in the FL-PCNL group (P value 0.460). There was no significant difference in the total operative time between both groups in our study as the mean operative time in the US-PCNL group was (61.47 ± 6.07 min) and (65.86 ± 20.86 min) in the FL-PCNL group with a (P value of 0.349). Stone-free rate was nearly similar in both groups (P value 0.336). Three cases in our study in the FL-PCNL group had bleeding that required blood transfusion post-operative; mean Hb change was 0.23 g/dL and 0.55 g/dL in US-PCNL and FL-PCNL groups, respectively, which is clinically irrelevant despite statistical significance (P value 0.007). Mean fluoroscopy time was (6.38 ± 3.84) minutes in FL-PCNL group.ConclusionUltrasound guidance is a reliable tool in the hands of experienced urologists in performing PCNL with less or even zero radiation.

Reducing hand radiation during renal access for percutaneous nephrolithotomy: a comparison of radiation reduction techniques

Percutaneous nephrolithotomy confers the highest radiation to the urologist’s hands compared to other urologic procedures. This study compares radiation exposure to the surgeon’s hand and patient’s body when utilizing three different techniques for needle insertion during renal access. Simulated percutaneous renal access was performed using a cadaveric patient and separate cadaveric forearm representing the surgeon’s hand. Three different needle-holding techniques were compared: conventional glove (control), a radiation-attenuating glove, and a novel needle holder. Five 300-s fluoroscopy trials were performed per treatment arm. The primary outcome was radiation dose (mSv) to the surgeon’s hand. The secondary outcome was radiation dose to the patient. One-way ANOVA and Tukey’s B post-hoc tests were performed with p < 0.05 considered significant. Compared to the control (3.92 mSv), both the radiation-attenuating glove (2.48 mSv) and the needle holder (1.37 mSv) reduced hand radiation exposure (p < 0.001). The needle holder reduced hand radiation compared to the radiation-attenuating glove (p < 0.001). The radiation-attenuating glove resulted in greater radiation produced by the C-arm compared to the needle holder (83.49 vs 69.22 mGy; p = 0.019). Patient radiation exposure was significantly higher with the radiation-attenuating glove compared to the needle holder (8.43 vs 7.03 mSv; p = 0.027). Though radiation-attenuating gloves decreased hand radiation dose by 37%, this came at the price of a 3% increase in patient exposure. In contrast, the needle holder reduced exposure to both the surgeon’s hand by 65% and the patient by 14%. Thus, a well-designed low-density needle holder could optimize radiation safety for both surgeon and patient.

Comparison of Efficacy of Percutaneous Nephrolithotomy between Supracostal and Subcostal Access in Patients with Renal Stone

Background: Percutaneous Nephrolithotomy (PCNL) is a prevalent surgical procedure for the treatment of large renal stones. The choice between supra-costal and sub-costal access is pivotal in optimizing patient outcomes. This study provides an in-depth comparison of these two approaches, contributing to the evolving discourse in urological surgery. Objective: To compare the efficacy and safety of supra-costal and sub-costal access in PCNL for the treatment of renal stones. Methods: A randomized controlled trial was conducted at the Department of Urology, Pakistan Institute of Medical Sciences, from May to October 2023. Sixty-four patients with renal stones larger than 2cm were enrolled and divided into two groups based on the access point: supra-costal (Group A) and sub-costal (Group B). Variables such as age, gender, duration of surgery, stone size, clearance rate, and complications were analyzed using Statistical Package for the Social Sciences (SPSS) Version 25. Results: The average age of participants was 37.20 ± 13.0 years, with surgery duration averaging 45.75 ± 4.98 minutes. The majority of participants were male (59.4%). Stone clearance rates were high in both groups (93.8% in Group A and 90.6% in Group B), with no statistically significant difference (P-value &gt; 0.05). Complication rates were 9.4% in Group A and 15.6% in Group B, also showing no significant difference. Conclusion: Both supra-costal and sub-costal accesses in PCNL are effective for renal stone clearance, with comparable success rates and complication profiles. The choice between these approaches can be based on individual patient anatomy and surgeon preference. Further research could explore long-term outcomes and patient-specific factors influencing the choice of access point.

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.

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.

Comparing the outcomes of papillary and non-papillary access in percutaneous nephrolithotomy.

Some publications have recently been released on the safety of non-papillary access (NPA) in percutaneous nephrolithotomy (PCNL) by a Greek group. The purpose of this study was to prospectively examine the outcome of NPA during two years in a referral center. This prospective cohort study was conducted on PCNL operations performed from January 2020 to April 2022 in Labbafinejad Hospital. In cases in which obtaining papillary access (PA) was not obtainable after several attempts and NPA was obtained, or in cases in whom after entry to the pyelocalyceal system, a NPA was observed, the cases were categorized in the NPA group (n = 67). The control group (PA) was composed of patients who had undergone PCNL with papillary access with similar stone bulk (n = 67). The primary endpoints of interest were hemoglobin drop and transfusion frequency. The secondary endpoint included: stone free rate (SFR), operation duration, and complications. A total of 134 patients were enrolled during the study period which included 33 female patients (25%). The mean ± SD age of patients was 49.6 ± 13.2years. The frequency of transfusion and residual stones was not different between NPA and PA groups: 6 (9%) versus 8 (11%), P = 0.29; and 16 (24%) versus 12 (18%), P = 0.26. Likewise, the operation time (87.6 ± 25.8 versus 90.2 ± 22.6min, P = 0.45), and the frequency of intraoperative and postoperative complications were not different between the NPA and PA groups. The results of this prospective study did not reveal a higher frequency of residual stones, transfusion, or complications in the NPA group. Nevertheless, our study is not powered enough to reveal complications of low frequency including delayed bleeding.

Percutaneous Nephrolithotomy Access: A Meta-Analysis Comparing Access by Urologist vs Radiologist.

Introduction: Percutaneous nephrolithotomy is a minimally invasive procedure indicated for the management of staghorn calculi or renal calculi >2.0 cm. Percutaneous renal access is a critical step in this procedure and can be performed by either urologists or interventional radiologists. The purpose of this study is to perform a meta-analysis to compare outcomes between urologist and interventional radiologist-mediated access. Methods: An electronic literature search was conducted to identify studies comparing urologist- and interventional radiologist-acquired access. Studies must have included both urologist- and intervention radiologist-acquired access data but were excluded if (1) not in English; (2) abstract without full text; (3) unable to determine who acquired access; and (4) only included either urologist or interventional radiologist data. Meta-analysis comparison was generated with the Review Manager 5.4 software. Results: After screening the abstracts and title, 55 relevant studies were identified. Nine articles were utilized in the meta-analysis. Urologist-acquired access was associated with a greater stone-free rate (risk ratio [RR] = 1.10; 95% confidence interval [CI], 1.01-1.20), a reduction in major complications (RR = 0.69; 95% CI, 0.53-0.92), and a shorter hospital stay (mean difference -0.40; 95% CI, -0.64 to -0.16) in comparison with radiologist-acquired access. Urologist-acquired access was associated with greater blood loss (mean difference 0.46; 95% CI, 0.32-0.60) when compared with interventional radiology-acquired access. No significant differences were found with regard to unusable access, multiple tracts, supracostal access, ancillary procedure requirement, operative time, minor complications, and transfusions. Conclusions: Urologist-acquired access may be associated with a higher stone-free rate and a reduction in major complications, whereas interventional radiologist-mediated access may be associated with a reduction in blood loss, despite similar transfusion rates.

Thoracic Complications in Supracostal Percutaneous Nephrolithotomy.

Due to the risk of pleural injury leading to thoracic complications, many urologist still hesitate to perform supracostal puncture during percutaneous nephrolithotomy. Our aim of this study was to evaluate the thoracic complications in supracostal access percutaneous nephrolithotomy. This is a retrospective analysis of 101 patients who were treated with supracostal access percutaneous nephrolithotomy at our institute from September 2013 and December 2019. Indications for supracostal punctures were staghorn 28(27.7%), middle calyceal stones 10(9.9%), pelvic stones 29(28.7%), complex inferior calyceal stones 26(25.7%), upper calyceal stone 10(9.9%)and upper ureteric stone17(16.8%).The intercostal space between the 11th and 12th ribs was used in all the cases. Among the 101 patients who undergone percutaneous nephrolithotomy by supracostal access, three patients (2.97%) had pleural injury. Among them one patient developed hydrothorax and needed chest tube insertion and remaining two patients had minimal pneumo thorax with blunting of costo-phrenic angle, which was managed conservatively. The lung parenchymal or other viscera injury was not observed in our study. Most punctures were, a single supracostal superior calyceal access 18(17.8%) and middle posterior calyceal access 88(82.2%), except for staghorn and multiple complex lower calyceal calculi needed multiple tracts 23(22.8%). Complete clearance was observed in 77(76.2%) patients. The supracostal puncture was a safe and effective approach with high stone clearance rate and acceptable morbidity in selected cases of staghorn, upper ureteral, and upper calyceal calculi. It should be adapted whenever needed and should not be avoided due to fear of chest complications.

Re: A Randomized, Single-blind Clinical Trial Comparing Robotic-assisted Fluoroscopic-guided with Ultrasound-guided Renal Access for Percutaneous Nephrolithotomy

Re: A Randomized, Single-blind Clinical Trial Comparing Robotic-assisted Fluoroscopic-guided with Ultrasound-guided Renal Access for Percutaneous Nephrolithotomy

Superior calyceal access vs. other calyceal access in percutaneous nephrolithotomy: A systematic review and meta-analysis.

PurposeTo evaluate the superior calyceal access’s performance and safety in relation to other calyceal access during percutaneous nephrolithotomy (PCNL).MethodsThe suggested reporting items for systematic reviews and meta-analysis were used to conduct this meta-analysis (PRISMA). To find pertinent studies for this meta-analysis, we searched PubMed, Embase, Web of Science, and China National Knowledge Infrastructure (CNKI). Operation time and hospital stay are two secondary outcomes, whereas failed stone clearance and complication events are the two major outcomes. Utilizing Stata 15.0, RevMan 5.3, and R 4.0.2, relative data were extracted and evaluated.ResultsThis meta-analysis was based on 16 studies with 8,541 individuals. Pooled results suggested that superior calyceal access could offer fewer failed stone clearance [odds ratio (OR): 0.64, 95% confidence interval (CI), 0.47–0.88, P = 0.006] and lower additional puncture rate (OR: 0.35, 95% CI, 0.24–0.51, P < 0.001) than other calyceal access. No complication difference was found (OR: 1.10, 95% CI, 0.78–1.56, P = 0.57). Superior calyceal access could offer shorter operation time [standard mean difference (SMD): −0.57, 95% CI, −0.98 to −0.15, P = 0.007]. No hospital stay difference was found (SMD: 0.07, 95% CI, −0.09 to 0.22, P = 0.38). Large heterogeneity was detected in stone clearance comparison (I2 = 71%, P < 0.001) and operation time (I2 = 97%, P < 0.001). The stone clearance comparison also identified significant publication bias (P = 0.026). These defects weaken the credibility of the results.ConclusionSuperior calyceal access in PCNL may result in a higher stone clearance rate, a lower rate of subsequent punctures, and a faster operation duration with no increase in postoperative complications or hospital stay for kidney stone patients, despite the significant heterogeneity and publication bias. By conducting bigger randomized controlled studies, this discovery still has to be confirmed.

Renal calyx access does not affect intraoperative blood loss in percutaneous nephrolithotomy: a single-center retrospective study

Objective: Percutaneous nephrolithotomy (PCNL) is one of the most effective ways of dealing with large renal calculi but also comes with a risk of intraoperative blood loss. Previous evidence is contradictory as regards the difference in blood loss between different renal calyx access. We conducted this study to compare intraoperative blood loss between different renal access calyx. Materials and Methods: We conducted a retrospective study analyzing 132 cases of single access PCNL, dividing them into an upper pole group (n = 93) and a non-upper pole group (n = 39). Intraoperative blood loss was calculated from pre-and post-operative hematocrit level, gender, body surface area, and amount of blood transfusion. Blood loss was compared between the two groups using univariable and multivariable analysis. Results: Overall blood loss was 500 ml (IQR 200-814 ml) with a median blood loss of 461 ml (IQR 158-738 ml) in the upper pole group and 650 ml (IQR 332-1233 ml) in non-upper pole group. Median hematocrit change was 2.9% and 3.9% in the upper and non-upper pole groups, respectively. The blood transfusion rate was 4.5% in the upper pole group and 8.3% in the non-upper pole group. The multivariable analysis did not demonstrate any statistically significant difference in average blood loss, hematocrit change or blood transfusion rate. Conclusions: Our study did not find any significant difference in intraoperative blood loss between different renal access routes in PCNL.

A Randomized, Single-Blind Clinical Trial Comparing Robotic-Assisted Fluoroscopic-Guided with Ultrasound-Guided Renal Access for Percutaneous Nephrolithotomy.

We conducted a randomized, single-blind clinical trial comparing the surgical outcomes of robotic-assisted fluoroscopic-guided (RAF group) and ultrasound-guided (US group) renal access in mini-percutaneous nephrolithotomy (PCNL). We recruited patients who underwent mini-PCNL with ureteroscopic assistance for large renal stones between January 2020 and May 2021. Block randomization was performed using online software. Automated needle target with x-ray was used for fluoroscopic-guided renal access in the RAF group. PCNL was performed by residents using a pneumatic lithotripsy system with 16.5Fr/17.5Fr tracts. The primary outcome was single puncture success, and the secondary outcomes were stone-free rate, complication rate, parameters measured during renal access and fluoroscopy time. In total, 71 patients (35 in US group, 36 in RAF group) were enrolled. No difference was seen in the single puncture success rate between the US and RAF groups (34.3% and 50.0%, p=0.2). In 14.3% cases in the US group vs no cases in the RAF group, the resident was unable to obtain access due to difficult targeting (p=0.025). The mean number of needle punctures was significantly fewer, and the median duration of needle puncture was shorter in the RAF group (1.83 vs 2.51 times, p=0.025; 5.5 vs 8.0 minutes, p=0.049, respectively). The stone-free rate at 3 months after surgery was 83.3% and 70.6% in the RAF and US groups, respectively (p=0.26). Multivariate analysis revealed that RAF guidance reduced the mean number of needle punctures by 0.73 times (p=0.021). RAF renal access in mini-PCNL may have further potential applications in this field.

MP14-18 ROBOTIC-ASSISTED ELECTROMAGNETIC GUIDANCE IMPROVES SUCCESS IN GAINING PERCUTANEOUS ACCESS FOR NEPHROLITHOTOMY BY NOVICES

You have accessJournal of UrologyCME1 May 2022MP14-18 ROBOTIC-ASSISTED ELECTROMAGNETIC GUIDANCE IMPROVES SUCCESS IN GAINING PERCUTANEOUS ACCESS FOR NEPHROLITHOTOMY BY NOVICES Mitchell Humphreys, Kevin Wymer, Ben Chew, Janet Zhen, Fuad Elkhoury, Sri Sivalingam, Matthew Dunn, and Michael Borofsky Mitchell HumphreysMitchell Humphreys More articles by this author , Kevin WymerKevin Wymer More articles by this author , Ben ChewBen Chew More articles by this author , Janet ZhenJanet Zhen More articles by this author , Fuad ElkhouryFuad Elkhoury More articles by this author , Sri SivalingamSri Sivalingam More articles by this author , Matthew DunnMatthew Dunn More articles by this author , and Michael BorofskyMichael Borofsky More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000002543.18AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Percutaneous nephrolithotomy (PCNL) offers advantages over retrograde intrarenal surgery for large stone burdens. However, gaining optimal access into the renal collecting system can be challenging and requires advanced training. A minority of PCNL access is currently performed by urologists in the USA. In this study, we evaluate the success of gaining percutaneous renal access in a cadaveric model when using a novel robotic-assisted electromagnetic (EM) guidance platform, compared to fluoroscopic guidance, among individuals that do not regularly perform their own PCNL access. METHODS: Seven novices (individuals who use IR for access, or gain percutaneous access <24 times/year, or have gained access <30 times after training) were asked to use robotic-assisted EM guidance provided by the Monarch® Platform, Urology (Auris Health, Inc., Redwood City, CA) to obtain upper pole, mid-kidney, and lower pole access in a modified-supine position vs. the same tasks in a prone position using fluoroscopy in a cadaveric model. The number of puncture attempts, accuracy (papilla/fornix, infundibulum, or miss), and time to achieve access was compared. Participants were also surveyed on their confidence in gaining access (Likert scale 1-5, 5 as the best score). Statistical comparisons were made using paired t-tests. RESULTS: Novices had increased overall success in gaining percutaneous access using robot-assisted EM navigation compared to fluoroscopy-guided (100% vs. 57%), with greater accuracy (papillary or forniceal) (100% vs. 29%) (Figure 1). Robotic-assisted EM guidance decreased the average number of insertion attempts per calyx (1.24±0.10 vs. 2.98±0.65, p<0.05), and also the time to achieve access (6.92±0.66 min vs. 16.90±3.21 min, p<0.05). Lastly, novices expressed a greater sense of ease [5(3.3-5) vs. 2.5(1-3)] and confidence [5(3.3-5) vs. 2(1-3)] in gaining access using EM- vs. fluoroscopy-guided navigation. CONCLUSIONS: Percutaneous access using robotic-assisted EM-guidance provided by the Monarch® Platform improved access success, time, accuracy, and confidence among study participants. These initial data suggest this novel enabling technology can benefit urologists to routinely gain their own access for PCNL. Source of Funding: Johnson & Johnson © 2022 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 207Issue Supplement 5May 2022Page: e239 Advertisement Copyright & Permissions© 2022 by American Urological Association Education and Research, Inc.MetricsAuthor Information Mitchell Humphreys More articles by this author Kevin Wymer More articles by this author Ben Chew More articles by this author Janet Zhen More articles by this author Fuad Elkhoury More articles by this author Sri Sivalingam More articles by this author Matthew Dunn More articles by this author Michael Borofsky More articles by this author Expand All Advertisement PDF DownloadLoading ...

PD40-12 ROBOTIC-ASSISTED ELECTROMAGNETIC GUIDANCE MINIMIZES RADIATION EXPOSURE IN GAINING PERCUTANEOUS ACCESS FOR NEPHROLITHOTOMY: A CADAVERIC STUDY WITH NOVICES

You have accessJournal of UrologyCME1 May 2022PD40-12 ROBOTIC-ASSISTED ELECTROMAGNETIC GUIDANCE MINIMIZES RADIATION EXPOSURE IN GAINING PERCUTANEOUS ACCESS FOR NEPHROLITHOTOMY: A CADAVERIC STUDY WITH NOVICES Mitchell Humphreys, Kevin Wymer, Ben Chew, Janet Zhen, Fuad Elkhoury, Sri Sivalingam, Matthew Dunn, and Michael Borofsky Mitchell HumphreysMitchell Humphreys More articles by this author , Kevin WymerKevin Wymer More articles by this author , Ben ChewBen Chew More articles by this author , Janet ZhenJanet Zhen More articles by this author , Fuad ElkhouryFuad Elkhoury More articles by this author , Sri SivalingamSri Sivalingam More articles by this author , Matthew DunnMatthew Dunn More articles by this author , and Michael BorofskyMichael Borofsky More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000002601.12AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Fluoroscopy plays a big role in endourologic stone procedures and intra-operative radiation exposure poses risks to the patient, surgeon, and staff. Fluoroscopic guidance is the most utilized imaging modality for obtaining access for percutaneous nephrolithotomy (PCNL). Radiation usage may also be higher by urologists who are less experienced. In this study, radiation use is compared while gaining percutaneous access in a cadaveric model, using either fluoroscopy or a novel robotic-assisted electromagnetic (EM) method in a cohort of novice urologist. METHODS: Seven novices (individuals who use IR for access, or gain percutaneous access <24 times/year, or have gained access <30 times after training) used robotic-assisted EM-guidance provided by the Monarch® Platform, Urology (Auris Health, Inc., Redwood City, CA) to obtain upper pole, mid kidney, and lower pole access in a modified supine position vs. the same tasks in a prone position using fluoroscopy in a human cadaver. Total radiation time and dosage, defined as from pyelogram to wire insertion, and access radiation time and dosage, defined as from needle insertion to wire insertion, were measured. Statistical comparisons were made using paired t-tests. RESULTS: Robot-assisted EM-guidance decreased total radiation time (0.11±0.01 min vs. 1.30±0.33 min, mean ±SEM, p<0.05) and total radiation dosage (1.00±0.15 mGy vs. 5.43±0.88 mGy, p<0.01), compared to fluoroscopy-guided navigation (Figure 1). Additionally, robotic-assisted EM-guidance reduced access radiation time (0.08±0.05 min vs. 1.08±0.24 min, p<0.01) and access radiation dosage (0.25±0.11 mGy vs. 4.25±0.86 mGy, p<0.01) compared to fluoroscopic-guidance. CONCLUSIONS: Robotic-assisted EM-guidance provided by the Monarch® Platform robotic system decreased radiation exposure when compared to fluoroscopic-guidance during percutaneous access in novice urologists with limited access experience. Keeping in mind the principals of ALARA, these limited data suggest that this novel technology could have significant benefits for patients and providers alike. Source of Funding: Johnson & Johnson © 2022 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 207Issue Supplement 5May 2022Page: e688 Advertisement Copyright & Permissions© 2022 by American Urological Association Education and Research, Inc.MetricsAuthor Information Mitchell Humphreys More articles by this author Kevin Wymer More articles by this author Ben Chew More articles by this author Janet Zhen More articles by this author Fuad Elkhoury More articles by this author Sri Sivalingam More articles by this author Matthew Dunn More articles by this author Michael Borofsky More articles by this author Expand All Advertisement PDF DownloadLoading ...

MP41-15 PCNL ACCESS PLANNING USING A NOVEL OPTIMIZATION ALGORITHM

You have accessJournal of UrologyCME1 May 2022MP41-15 PCNL ACCESS PLANNING USING A NOVEL OPTIMIZATION ALGORITHM Moiz Khan, Filipe De Carvalho Pedrosa, Lexuan Wang, Borna Dabiri, Rajni Patel, Jayender Jagadeesan, and Dianne Sacco Moiz KhanMoiz Khan More articles by this author , Filipe De Carvalho PedrosaFilipe De Carvalho Pedrosa More articles by this author , Lexuan WangLexuan Wang More articles by this author , Borna DabiriBorna Dabiri More articles by this author , Rajni PatelRajni Patel More articles by this author , Jayender JagadeesanJayender Jagadeesan More articles by this author , and Dianne SaccoDianne Sacco More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000002607.15AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Our objective is to evaluate a novel algorithm to assist with renal calyx access planning for percutaneous nephrolithotomy (PCNL). METHODS: An optimization algorithm was developed that determines the optimal skin access and trajectory to calyx/stone for PCNL procedures. The algorithm generated renal access takes into consideration the patient-specific organs, location and size of the stone, calyceal anatomy, access length from the skin to calyx and the trajectory to the ureteropelvic junction (UPJ). To validate the algorithm, 4 urologists and 4 radiologists were asked to provide their preferred access for 15 PCNL procedures based on the diagnostic CT images, and then score the algorithm proposed renal access using a rating scale as 1 (unacceptable), 2 (acceptable and as good as an expert solution) or 3 (better than expert solution). RESULTS: The optimization algorithm solution was rated by experienced experts to be just as good or better than the preferred renal access in 92% of cases, giving an average rating of 2.6 out of 3 (between acceptable and better than expert solution). The average difference between the stone/calyx access point when comparing the expert and algorithm was 1.1 cm (std=0.8 cm) in the medio-lateral direction, 1.3 cm (std=0.5 cm) in the anterio-posterior direction, and 2.8 cm (std=1.6 cm) in the cranio-caudal direction. The distance between the percutaneous access was 2.8 cm (s=1.7 cm) in the medio-lateral direction, 2.3 cm (std=1.6 cm) in the anterio-posterior direction, and 6.6 cm (std=3.2 cm) in the cranio-caudal direction. Experts had an average tract length of 83.7 mm, compared to 87.9 mm by the algorithm and angle of insertion to the ureteropelvic junction of 151.3 deg to 152.3 deg, respectively. There was no significant difference between the experts and algorithm in these findings (p >0.5). CONCLUSIONS: Initial evaluation yielded good performance of the algorithm in specifying a skin access site and trajectory into the calyx when planning a PCNL. The algorithm offers a valuable optimization tool for preoperative surgical planning and verification, and potential resident training tool. Figure Caption: (top) Surgical plan, green line shows the algorithm output. (bottom) Red line is the solution provided by the algorithm and green line is a representative expert solution. Source of Funding: NIH R01DK119268 © 2022 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 207Issue Supplement 5May 2022Page: e726 Advertisement Copyright & Permissions© 2022 by American Urological Association Education and Research, Inc.MetricsAuthor Information Moiz Khan More articles by this author Filipe De Carvalho Pedrosa More articles by this author Lexuan Wang More articles by this author Borna Dabiri More articles by this author Rajni Patel More articles by this author Jayender Jagadeesan More articles by this author Dianne Sacco More articles by this author Expand All Advertisement PDF DownloadLoading ...

Safety and Efficacy of Supracostal Access for Percutaneous Nephrolithotomy (PCNL) for Renal Stones

Objective: To evaluate the Safety and Efficacy of supra-costal access of percutaneous nephrolithotomy (PCNL) for renal stones. Methods: This cross-sectional study constituting 160 patients who underwent PCNL via the supra-costal approach was conducted from January 2018 to March 2021 in Recep Tayyip Erdoğan Hospital, Muzaffargarh. The supra-costal access was achieved through the 11th intercostal space. The success rate and complications were noted. Bleeding, pneumothorax and hydrothorax were noted as major complications. Results: Mean age of patients was 36.06±14.57 years. There were 86 (53.7%) male and 74 (46.3%) female patients. In majority patients the stone size was 2.0 to 2.5 cm in 76 (47.5%) patients. Stone clearance was achieved successfully in 114 (71.3%) patients. The overall procedural complications rate was 54 (33.7%). The commonest complication was bleeding that occurred in 44 (27.5%) patients, hydrothorax in 7 (4.4%) patients, and bleeding plus hydrothorax in 3 (1.9%) patients. Conclusion: PCNL performed using supra-costal access is effective and safe with minimal complications rate. Supra-costal access can be adopted as a safe and effective access for PCNL especially in patients with complex renal stones. Keywords: Renal stones, Percutaneous nephrolithotomy, Supra-costal access.

Intravenous Pyelogram (IVP)-Based Guy’s Stone Score (GSS) Utility for Prediction of Outcomes of Upper Pole Access Percutaneous Nephrolithotomy (PCNL)

Background: Renal stone disease is a very common disease, and its lifetime prevalence is 1 - 15%, with a gradual rise in incidence and disease prevalence. There are significant financial implications of its management. Nowadays, for big (typically &gt; 2 cm) renal and upper ureteric stones, PCNL is widely regarded as the first-line treatment. Because most of the intrarenal collecting systems can be accessed by superior calyceal puncture in PCNL, good stone clearance can be achieved. The “Guy’s Stone Score” is a useful technique for categorizing the complexity of PCNL. Objectives: This study aimed to evaluate the role of Guys Stone Score based on KUB and intravenous urography to predict the success rate, grading, and complexity of PCNL, which are performed via the upper pole access. Methods: The present prospective, non-randomized observational study was undertaken in the Department of Urology and Renal transplantation, SCBMCH, Cuttack, from 1st November 2017 to 31st October 2019. A total of 104 patients were enrolled in the study in whom PCNL was performed through superior calyceal puncture, based on preoperative intravenous pyelogram. The Guy's Stone Score was calculated, and the complexity of the procedure was graded using radiological studies, then the outcome was determined accordingly. Results: In this study, 59.6% of the patients had immediate success among them 29.0% had grade 3, and 6.5% had grade 4 GSS. Moreover, 38.4% of the patients had clinically significant residual fragments among them, 75.0% had grade 4, and 20.0% had grade 3 GSS.23% of the patients underwent REDO-PCNL and 11.5% of the patients underwent accesory/ancillary procedure of ESWL. Conclusions: The present study shows that an intravenous pyelogram-based Guy’s Stone Score (GSS) is an easy-to-use tool in predicting the early success rate and potential difficulties and complications in PCNL performed through superior calyceal puncture.

Renal puncture access using a blunt needle: proposal of the blunt puncture concept

PurposeSevere haemorrhage in percutaneous nephrolithotomy (PCNL) is an alarming event, and preventing injury to renal major vessels is a challenge. We evaluated the efficiency of a blunt needle in renal puncture procedures.MethodsWe first retrospectively reviewed the embolization images of post-PCNL patients to analyse the types of arteries injured, which were considered target arteries. Then, either a blunt needle or a conventional needle was used to directly puncture target arteries in ex vivo porcine kidneys and to establish renal access ex vivo and in vivo. The primary outcome was the incidence of target artery injuries, which were observed by digital subtraction angiography, nephroscopy and 3-dimensional endocasts. The secondary outcome was the rate of excreted fluid per access.ResultsThe segmental and interlobar arteries were the most common types of injured arteries that needed to be embolized after PCNL. When these arteries were punctured directly, blunt needles reduced injury (1/20 vs. 16/20; OR 4.750; 95% CI 1.966–11.478; P < .001) by 76% compared to injuries induced by conventional needles. Moreover, the blunt needle group also had a significantly lower incidence of these arteries’ injuries ex vivo due to renal puncture and yielded a lower rate of excreted fluid in ex vivo and in vivo renal puncture procedures.ConclusionA blunt needle for renal puncture can be effective in reducing injury to renal major arteries and the accompanying haemorrhage. We propose the concept of blunt puncture, which may be a promising method for achieving safe renal access in PCNL.

One-shot dilation versus metallic dilation technique for access in percutaneous nephrolithotomy: comparison of efficacy, access time and fluoroscopic time

Objective: The aim of this study was to compare the efficacy, access tract dilation time and fluoroscopic time between the one-shot dilation technique and telescopic metal dilatation technique in patients undergoing percutaneous nephrolithotomy in Nakornping Hospital. Materials and Methods: Sixty-six patients who underwent percutaneous nephrolithotomy from January 2020 to July 2021 were included in the study and they were randomly divided into two groups. In group 1 (32 patients), telescopic metal dilation was used, in group 2 (33 patients), the one-shot technique was used. Success rates of dilation, access tract dilation time and fluoroscopic time were evaluated. Results: The success rate of dilation was 100% in both groups. The access tract dilation time was 835.63 ± 309.68 seconds in group 1 and 569.42 ± 314.75 seconds in group 2 (p = 0.001). The fluoroscopic time was 48.16 ± 22.16 seconds in group 1 and 41.97 ± 23.99 seconds in group 2 (p = 0.29). The access tract dilation time of the one-shot dilation technique was statistically significantly shorter than that in the telescopic metal dilatation group. The mean fluoroscopic time of the one- shot dilation technique was shorter than in telescopic metal dilatation but was not statistically significant. Conclusion: One-shot dilation technique is as effective as telescopic metal dilatation, with a significant reduction in access tract dilation time.