Ultrasound versus fluoroscopy as imaging guidance for percutaneous nephrolithotomy: A systematic review and meta-analysis

OBJECTIVES

To determine whether the outcomes of ultrasound-guided percutaneous nephrolithotomy (UG-PCNL), an alternative to traditional fluoroscopy-guided percutaneous nephrolithotomy (FG-PCNL), are comparable.

METHODS

A systematic search of PubMed, Embase, and the Cochrane Library was carried out to discover investigations comparing UG-PCNL to FG-PCNL, and accordingly, a meta-analysis of those studies was performed. The primary outcomes included the stone-free rate (SFR), overall complications based on Clavien-Dindo classification, duration of surgery, duration of patients' hospitalization, and hemoglobin (Hb) drop during the surgery. All statistical analyses and visualizations were implemented utilizing R software.

RESULTS

Nineteen studies, including eight randomized clinical trials (RCTs) and eleven observational cohorts, comprising 3016 patients (1521 UG-PCNL patients) and comparing UG-PCNL with FG-PCNL met the inclusion criteria of the current study. Considering SFR, overall complications, duration of surgery, duration of hospitalization, and Hb drop, our meta-analysis revealed no statistically significant difference between UG-PCNL and FG-PCNL patients, with p-values of 0.29, 0.47, 0.98, 0.28, and 0.42, respectively. Significant differences were discovered between UG-PCNL and FG-PCNL patients in terms of the length of time they were exposed to radiation (p-value< 0.0001). Moreover, FG-PCNL had shorter access time than UG-PCNL (p-value = 0.04).

CONCLUSION

UG-PCNL provides the advantage of requiring less radiation exposure while being just as efficient as FG-PCNL; thus, this study suggests prioritizing the use of UG-PCNL.

A 3D printing personalized percutaneous puncture guide access plate for percutaneous nephrolithotomy: a pilot study

OBJECTIVE

CT-Urography combined with 3D printing technology, digital design, construction of individualized PCNL puncture guides, and preliminary analyze their efficacy, safety puncture positioning for PCNL.

METHODS

Twenty-two patients with renal calculi were randomly selected at the affiliated Hospital of Xuzhou Medical University during 2017-2018. We randomly divided the patients into two groups: in 10 experimental groups, we used our 3D printing personalized percutaneous puncture guide access plate for PCNL, and in the control group, 12 patients with standard USG guide PCNL. The accuracy of puncture position, puncture time, and intraoperative blood loss was compared.

RESULTS

In the experimental group, 10 patients with 3D printing personalized percutaneous puncture guide access plate. The puncture needle was accessed through the guide plate and verified by the color Doppler. The single puncture, needle position, and depth success rate were 100.00% (10/10). The angles were consistent with the preoperative design. In the control group, 12 patients via USG guided PCNL success rate was 75.00% (9/12). The puncture time and amount of hemorrhage was (7.78 ± 0.94) min and (49.31 ± 6.43) mL, and (9.04 ± 1.09) min and (60.08 ± 12.18) mL, respectively. The above data of the two groups were statistically significant (P < 0.05).

CONCLUSION

3D printing personalized percutaneous nephrolithotomy guide plate for PCNL can improve PCNL renal puncture channel positioning accuracy, shorten puncture time, reduce intraoperative blood loss, bleeding-related complications and provide a new method for PCNL renal puncture positioning, which is worthy of further clinical exploration.

Comparison of contrast-enhanced ultrasound versus conventional ultrasound-guided percutaneous nephrolithotomy in patients with nondilated collecting system: a randomized controlled trial

OBJECTIVE

To compare the safety, effectiveness, and feasibility of contrast-enhanced ultrasound (CEUS) versus conventional ultrasound-guided percutaneous nephrolithotomy (PCNL) in patients with nondilated collecting system.

METHODS

Between July 2018 and July 2020, 160 kidney stone patients with nondilated collecting system planned for PCNL were randomly assigned into two groups, CEUS with retrograde ureteral contrast injection and conventional ultrasound with retrograde ureteral normal saline injection. Patient's demographics, the success rate of puncture, success rate of a single-needle puncture, number of punctures, puncture time, perioperative outcomes, stone-free rate, and incidence of complications were compared.

RESULTS

The success rate of a single-needle puncture for CEUS-guided PCNL was higher than that in the conventional ultrasound group (88.5% vs. 73.7%, p = 0.02). Patients performed with CEUS-guided PCNL required less needle passes (p = 0.02), shorter needle puncture time (p = 0.031), and shorter channel establishment time (p = 0.04) than those guided with conventional ultrasound. The postoperative hemoglobin decrease in the CEUS-guided PCNL group was less than that of the control group (p = 0.02). There was no significant difference in operating time, length of hospital stays, kidney function change, and complications between the two groups (p > 0.05). The 1-month stone-free rate was 94.9% in the CEUS group and 90.8% in the control group (p > 0.05).

CONCLUSIONS

Compared with conventional ultrasound, CEUS-guided PCNL may facilitate ultrasound-guided PCNL for patients without hydronephrosis, and benefited with a higher success rate of a single-needle puncture, less needle passes, shorter puncture time, and lower postoperative Hb drop.

TRIAL REGISTRATION

Chinese Clinical Trial Registry: ChiCTR1800016981 KEY POINTS: • Compared with conventional ultrasound, CEUS-guided PCNL is a safe and efficacious procedure for kidney stone patients with nondilated collecting system. • Compared with conventional ultrasound, CEUS-guided PCNL benefited with a higher success rate of a single-needle puncture, less needle passes, shorter puncture time, and lower postoperative Hb drop. • CEUS-guided PCNL associated with the more accurate needle puncture and acceptable complications.

Interior definition of the calyceal orientation suitable for percutaneous nephrolithotripsy via mobile software

To date, there is no paper on defining the puncture of a kidney from the interior view of the pelvicalyceal system (PCS) to alleviate its performance. The objective of this study is to define the usefulness of the Rubik's Cube method determining calyceal orientation from inside via mobile software for the percutaneous nephrolithotripsy (PCNL). Over September 2019-September 2020, 25 patients with indications for PCNL were enrolled in this single-arm study. All patients underwent computed tomography (CT)-urography. Primary endpoints were the duration of renal cavity puncture, number of attempts and success rate. Complication rate ordered according to Clavien-Dindo classification was analyzed as a secondary endpoint. The stone-free rate was 91%. The same experienced urologist performed all procedures through the single-access PCNL without puncture site reposition. The puncture was made through the upper, middle, and lower calyx in 9, 12 and 4 cases, respectively. The mean duration of cavity puncture was 2.8 ± 1.1 min. The mean number of attempts to reach desirable calyx was 1.4 ± 0.6. It should be noted that there were no cases with three and more punctures. The overall complication rate was 28% (7/25) when only one patient experienced ≥ 3 Grade. The proposed Rubik's Cube method facilitates preoperative planning of PCNL and makes that procedure easier for specialists and safer for the patients.

Outcomes of ultrasound-guided percutaneous nephrolithotomy for the treatment of large stones within non-functioning atrophic kidneys

OBJECTIVES

To evaluate outcomes in patients who underwent total ultrasound-guided percutaneous nephrolithotomy for the management of large stones (>2 cm) within non-functioning atrophic kidneys, and to identify risk factors associated with postoperative persistence of urinary tract infection symptoms in such patients.

METHODS

Between December 2014 and May 2019, 56 patients with large stones within non-functioning atrophic kidneys were treated at Beijing Tsinghua Changgung Hospital, Beijing, China, with total ultrasound-guided percutaneous nephrolithotomy. Factors including age, sex, previous medical history, stone burden, stone composition, stone-free rate, complication rate and postoperative urinary tract infection symptoms were retrospectively evaluated. Uni- and multivariate analyses were carried out to identify risk factors that predict persistence of urinary tract infection symptoms after percutaneous nephrolithotomy in such patients.

RESULTS

The final stone-free rate after auxiliary treatments was 87.5%. The overall complication rate was 17.9%. After a median follow-up period of 12 months (range 6-40 months), three patients (5.4%) ultimately underwent nephrectomy. A total of 44 patients (78.6%) had no symptoms of urinary tract infection during follow up, whereas 63.6% of patients with diabetes continued to show persistent urinary tract infection symptoms at the latest follow up. Five patients (8.9%) showed improved total renal function, while most patients (83.9%) showed a stable estimated glomerular filtration rate. Diabetes was the only factor showing statistical significance in both univariate and multivariate analyses that predicted persistence of urinary tract infection symptoms after treatment with percutaneous nephrolithotomy.

CONCLUSIONS

Ultrasound-guided percutaneous nephrolithotomy is a safe and feasible procedure that can be carried out in patients with large stones within non-functioning atrophic kidneys. However, for such patients with diabetes, percutaneous nephrolithotomy is not recommended.

Ultrasound or Fluoroscopy for Percutaneous Nephrolithotomy Access, Is There Really a Difference? A Review of Literature

Objective: To compare whether the outcomes of ultrasound-guided access percutaneous nephrolithotomy (USGA-PCNL) are similar to standard fluoroscopy-guided access percutaneous nephrolithotomy (FGA-PCNL). Methods: A review was developed by using the MEDLINE and Scopus databases and following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses protocol. Studies comparing the USGA-PCNL and the FGA-PCNL were included. Case reports, editorials and letters, unpublished studies, posters, and comments abstracts were excluded. Results: We found 12 published articles that compared USGA-PCNL and FGA-PCNL. These included six randomized controlled trials, three case-control trials, and three meta-analyses. The overall results showed no difference in the success of percutaneous access, bleeding, blood transfusion, operative time, postoperative complications, or hospital stay. Conclusion: The reported data demonstrate that there are no significant differences between the fluoroscopic-guided access PCNL and the ultrasonographic access PCNL. The choice of puncture depends on the surgeon's expertise in a particular technique and the patient and stone characteristics. Both approaches are equally safe and effective in experienced hands. It is important to recall that the use of one technique does not exclude the use of the other, and they can sometimes be complementary to each other.

Retrograde intrarenal surgery without fluoroscopy: Is it possible? A randomized prospective study, an extraordinary experience

OBJECTIVES

The aim of this study was to evaluate the role of the use of fluoroscopy in patients undergoing retrograde intrarenal surgery and the effect on surgical outcomes.

MATERIAL AND METHODS

The patients who were admitted to our center with the diagnosis of kidney stones were divided into 2groups. In group 1, routine fluoroscopy was used in all cases (n: 58). In group 2, the same procedure was performed without fluoroscopy (n: 67) and the results of the 2groups were compared.

RESULTS

There were no statistically significant differences between the 2groups in terms of operation time, stone-free rate, complication rate, need for analgesic and re-treatment requirement and Visual Analogic Scale score.

CONCLUSION

The use of fluoroscopy does not alter the complication frequency and stone-free rate. We think that the use of fluoroscopy is not mandatory in cases in which renal pelvis access is achieved especially with semirigid ureteroscopy and that unnecessary fluoroscopy increases radiation exposure.

Updates in endourological management of urolithiasis

Urinary stone disease, or urolithiasis, is a very common disease with increasing prevalence and incidence. With the advancement of endoscopic techniques, the treatment outcomes of ureteroscopy (or transureteral lithotripsy) and percutaneous nephrolithotomy are continuously improving. In recent years, there have been many new developments in the field, including new endoscopy design, more effective auxiliary tools, improvement in treatment protocols, introduction of robotic technology, combining both ureteroscopy and percutaneous nephrolithotomy (endoscopic combined intrarenal surgery or transureteral lithotripsy-assisted percutaneous nephrolithotomy), improvement in laser technology, and so on. All these new inputs will further improve the treatment efficacy and safety of the procedures, thus benefiting our patients. In the present review, we briefly go through the main steps of ureteroscopy and percutaneous nephrolithotomy, with a concise description and application of these new advances.

Ultrasound-guided versus fluoroscopy-guided percutaneous nephrolithotomy: a systematic review and meta-analysis

PURPOSE

To evaluate the efficacy and safety of ultrasound-guided (UG) versus fluoroscopy-guided (FG) percutaneous nephrolithotomy (PCNL).

METHODS

A systematic search of PubMed (MEDLINE), Embase, and the Cochrane Library was conducted to identify randomized controlled trials that compared UG-PCNL with FG-PCNL, and a meta-analysis of those studies was completed. The primary outcomes assessed were stone-free rate (SFR) and complication rate. Secondary outcomes assessed were the successful access-creation rate, time necessary for entrance into the target calyx, auxiliary procedure rate, transfusion rate, hemoglobin decrease after surgery, surgery duration, and hospital stay.

RESULTS

Eight studies comprising 966 patients were included in the meta-analysis. Compared with FG-PCNL, UG-PCNL had comparable stone-free rates [odds ratio (OR) 0.95; 95% confidence interval (CI) 0.67-1.35; p = 0.79] irrespective of the patient's position, and a favorable safety profile resulting in a lower complication rate (OR 0.56; 95% CI 0.36-0.86; p = 0.009). No statistical difference was found between UG and FG groups in secondary outcomes.

CONCLUSIONS

UG-PCNL is as effective as FG-PCNL and has the advantage of lower complication rates. In addition, UG-PCNL could be performed with patients in the supine position without compromising its efficacy.

Clinical application of super-mini PCNL (SMP) in the treatment of upper urinary tract stones under ultrasound guidance

PURPOSE

To present the safety and efficacy of totally ultrasonography-guided Super-mini percutaneous nephrolithotomy (SMP) in the treatment of upper urinary tract stones both in children and adults.

PATIENTS AND METHODS

We carried out SMP in 104 patients (including 48 children and 56 adults) with upper urinary tract stones between June 2015 and February 2017. All steps of renal access were performed by ultrasonography. The lithotripsy was performed using either Holmium laser or pneumatic lithotripter. Perioperative and postoperative parameters along with operative data were recorded in detail.

RESULTS

The mean age of children and adult patients were 4.4 ± 3.6 and 44.3 ± 15.7 years old, respectively. The stone burden was comparable for both groups (1.72 ± 0.66 vs 1.74 ± 0.56 cm, p = 0.852). Mean operation time was not significant different between two groups (p = 0.052), while the mean haemoglobin drop in children was much lower in adult patients (6.3 ± 6.9 vs 10.9 ± 8.69, p = 0.004). Both groups had similar SFRs in postoperative 1 day and at 1-month follow-up (p = 1.000, p = 0.912). Mean hospital stay of children and adult patients was 2.3 ± 0.8 and 2.2 ± 0.76 days (p = 0.484). The total complication rate was significantly lower in two groups (p = 1.000); none of the patients required blood transfusion.

CONCLUSIONS

Ultrasonography-guided SMP was a safe and effective treatment option for moderate-sized upper urinary tract stones, and has the advantage of preventing radiation hazard, especially for pediatric stone patients.

A prospective and randomised trial comparing fluoroscopic, total ultrasonographic, and combined guidance for renal access in mini-percutaneous nephrolithotomy

OBJECTIVE

To compare the safety and efficacy of fluoroscopic guidance (FG), total ultrasonographic guidance (USG), and combined ultrasonographic and fluoroscopic guidance (CG) for percutaneous renal access in mini-percutaneous nephrolithotomy (mini-PCNL).

PATIENTS AND METHODS

The present study was conducted between July 2014 and May 2015 as a prospective randomised trial at the First Affiliated Hospital of Guangzhou Medical University. In all, 450 consecutive patients with renal stones of >2 cm were randomised to undergo FG, USG, or CG mini-PCNL (150 patients for each group). The primary endpoints were the stone-free rate (SFR) and blood loss (haemoglobin decrease during the operation and transfusion rate). Secondary endpoints included access failure rate, operating time, and complications. S.T.O.N.E. score was used to document the complexity of the renal stones. The study was registered at http://clinicaltrials.gov/ (NCT02266381).

RESULTS

The three groups had similar baseline characteristics. With S.T.O.N.E. scores of 5-6 or 9-13, the SFRs were comparable between the three groups. For S.T.O.N.E. scores of 7-8, FG and CG achieved significantly better SFRs than USG (one-session SFR 85.1% vs 88.5% vs 66.7%, P = 0.006; overall SFR at 3 months postoperatively 89.4% vs 90.2% vs 69.8%, P = 0.002). Multiple-tracts mini-PCNL was used more frequently in the FG and CG groups than in the USG group (20.7% vs 17.1% vs 9.5%, P = 0.028). The mean total radiation exposure time was significantly greater for FG than for CG (47.5 vs 17.9 s, P < 0.001). The USG had zero radiation exposure. There was no significant difference in the haemoglobin decrease, transfusion rate, access failure rate, operating time, nephrostomy drainage time, and hospital stay among the groups. The overall operative complication rates using the Clavien-Dindo grading system were similar between the groups.

CONCLUSIONS

Mini-PCNL under USG is as safe and effective as FG or CG in the treatment of simple kidney stones (S.T.O.N.E. scores 5-6) but with no radiation exposure. FG or CG is more effective for patients with S.T.O.N.E. scores of 7-8, where multiple percutaneous tracts may be necessary.

Use of Volume Rendered, Maximum Intensity Projection Images to Assess Whether the Medial Calyx Synonymous with the Posterior Calyx

INTRODUCTION

This paper attempts to verify the anatomical veracity of the belief that in order to enter into a posterior calyx one must aim for the medial calyx during a percutaneous nephrolithotomy (PCNL).

METHODS

Volume rendered and maximum intensity projection reconstructions of normal pelvicalyceal systems were assessed in various rotational planes. An experienced urologist decided the appropriate access for PCNL in the upper, interpole and lower calyx on each side. The selected calyx was then viewed on anteroposterior sections to decide whether they were projecting laterally or medially.

RESULTS

Of the 508 calyces studied, the posterior calyx was projecting laterally in 72% and medially in 28%. In the upper calyx, the posterior calyx was projecting laterally in a majority of cases, 94% on the right and 89% on the left. In the right lower calyx, the posterior calyx was pointing laterally in 86%, whereas the distribution on the left was 64%.

CONCLUSION

Our results refute the belief that the medial calyx is always synonymous with the lateral calyx.

Solo Sonographically Guided PCNL under Spinal Anesthesia: Defining Predictors of Success

Aim. Sonography has been brought in percutaneous nephrolithotripsy (PCNL) as an adjunct to or substitute for X-ray to restrict radiation exposure. This study was designed to investigate the possible predictors for the success of the solo sonographically guided PCNL. Methods. 148 consecutive cases were prospectively enrolled. All steps of PCNL were performed solely with sonography guidance under spinal anesthesia. Residual stones were evaluated the day after surgery using sonography and plain radiography. Results. The mean age was 46 ± 15 years; 40% of kidneys had hydronephrosis. The mean stone burden was 504 ± 350 mm(2). The mean duration of surgery was 43 ± 21 minutes. The early stone-free rate was 92% in inferior or middle calyceal stones, 89.5% in single pelvic stones, 81.5% in partial staghorn stones, and 61.9% in staghorn stones. The mean residual stone size was 13 ± 8 mm. Logistic regression showed that a lower age and a larger stone burden significantly predicted positive residual stones. Fifteen percent of patients presented with grade I or II and six percent showed grade III complication based on Clavien classification. There was no cases of organ injury or death. Conclusion. Solo ultrasonographically guided PCNL under spinal anesthesia is feasible with an acceptable stone-free rate and complication rate.

Comparing Bleeding Complications of Double and Single Access Totally Tubeless PCNL: Is It Safe to Obtain More Accesses?

PURPOSE

To assess bleeding complications in totally tubeless double-access percutaneous nephrolithotomy (PCNL) and compare it with the single-access method.

METHODS

One hundred and seven patients with large or scattered renal stones were enrolled in this cohort study. Totally tubeless PCNL with one access (group A, 70 cases) or two accesses (group B, 37 cases) was done and bleeding was assessed by measuring the hemoglobin drop of the patients, blood transfusion rate and need for performing angioembolization.

RESULTS

The mean (SD) hemoglobin drops in groups A and B were 1.97 (1.24) and 2.31 (1.24), respectively; p = 0.176. Blood transfusion rates in two groups were 7.1 and 10.8% (p = 0.716), respectively. None of our patients required angioembolization. The average hemoglobin drop and blood transfusion rate with double tracts were approximately near to those in single tract group and in acceptable ranges. The average hospital stay in groups A and B were 3.1 and 3.2 days (p = 0.074), respectively. There was no leakage from puncture site/s and stone free rates in the two groups were 85.7 and 97.3% (p = 0.093).

CONCLUSION

Totally tubeless double-access PCNL is feasible and bleeding complications are comparable to single access totally tubeless PCNL making it an effective strategy to achieve more stone free rates.