Management of calyceal diverticular calculi: a comparison of percutaneous nephrolithotomy and flexible ureterorenoscopy

Efficacy of flexible ureterorenoscopy with holmium laser in the management of calyceal diverticular calculi

The purpose of this study was to evaluate the efficacy and safety of flexible ureteroscopy with holmium laser lithotripsy in the management of calyceal diverticular calculi. In this study, we retrospectively analyzed the clinical data of 27 patients with calyceal diverticular calculi admitted to the Department of Urology of the Zigong First People's Hospital from May 2018 to May 2021. Intraoperatively, the diverticular neck was found in all 27 patients, but flexible ureterorenoscopy lithotripsy was not performed in 2 cases because of the slender diverticular neck, and the success rate of the operation was 92.6%. Of the 25 patients with successful lithotripsy, the mean operative time was 76.9 ± 35.5 (43-200) min. There were no serious intraoperative complications such as ureteral perforation, mucosal avulsion, or hemorrhage. Postoperative minor complications (Clavien classification I-II) occurred in 4 (16%) patients. The mean hospital stay was 4.4 ± 1.7 (3-12) days. The stone-free rate was 80% at the 1-month postoperative follow-up. After the second-stage treatment, the stone-free rate was 88%. In 22 cases with complete stone clearance, no stone recurrence was observed at 5.3 ± 2.6 (3-12) months follow-up. This retrospective study demonstrated that flexible ureterorenoscopy with holmium laser is a safe and effective choice for the treatment of calyceal diverticular calculi, because it utilizes the natural lumen of the human body and has the advantages of less trauma, fewer complications, and a higher stone-free rate.

PCNL vs RIRS in management of stones in calyceal diverticulum: outcomes from a global multicentre match paired study that reflects real world practice

INTRODUCTION

Calyceal diverticulum (CD) is the outpouching of a calyx into the renal parenchyma, connected by an infundibulum. Often associated with recurrent stones, common surgical options include percutaneous nephrolithotomy (PCNL) or retrograde intrarenal surgery (RIRS). We aim to present the real-world practises and outcomes comparing both approaches and the technical choices made.

MATERIALS AND METHODS

Retrospective data including 313 patients from 11 countries were evaluated. One hundred and twenty-seven underwent mini-PCNL and one hundred and eighty-six underwent RIRS. Patient demographics, perioperative parameters, and outcomes were analysed using either T test or Mann-Whitney U test. Categorical data between groups were analysed using the Chi-squared test. Propensity score matching (PSM) was performed matching for baseline characteristics. Subgroup analyses for anomalous/malrotated kidneys and difficult diverticulum access were performed.

RESULTS

After PSM, 123 patients in each arm were included, with similar outcomes for stone-free rate (SFR) and complications (p < 0.001). Hospitalisation was significantly longer in PCNL. Re-intervention rate for residual fragments (any fragment > 4 mm) was similar. RIRS was the preferred re-intervention for both groups. Intraoperative bleeding was significantly higher in PCNL (p < 0.032) but none required transfusion. Two patients with malrotated anatomy in RIRS group required transfusion. Lower pole presented most difficult access for both groups, and SFR was significantly higher in difficult CD accessed by RIRS (p < 0.031). Laser infundibulotomy was preferred for improving diverticular access in both. Fulguration post-intervention was not practised.

CONCLUSION

The crux lies in identification of the opening and safe access. Urologists may consider a step-up personalised approach with a view of endoscopic combined approach where required.

Retrograde intrarenal surgery for stones associated with renal anomalies: caliceal diverticulum, horseshoe kidney, medullary sponge kidney, megacalycosis, pelvic kidney, uretero-pelvic junction obstruction

PURPOSE OF REVIEW

Nowadays, due to the increase of imaging diagnosis, we identify easily renal anomalies, and we can choose between a wide range of armamentarium to treat symptomatic stones in those challenging cases. However, there is a lack of evidence and consensus on its use. The aim of this narrative review is to collect all the available data about safety and efficacity of retrograde intrarenal surgery (RIRS) in the treatment of kidney stones associated to a renal anomaly.

RECENT FINDINGS

Renal anomalies are uncommon findings and even more if it has to be associated with renal stones. After a literature review of the past 2 years, there are a small number of studies that compare the outcomes in patients who have been treated with minimally invasive modalities and they are mainly focus on RIRS.

SUMMARY

It is of extreme importance to know the advances on the stone treatment in anomalous kidneys. With the development of new laser technologies, RIRS is becoming a more interesting technique with high success rate and safety. Further studies are needed to make an accurate statement about the adequate surgical technique for each renal anomaly and also, clinical trials using new laser technologies.

The treatment option for calyceal diverticulum stones: flexible ureteroscopy lithotripsy (FURL) or all-seeing needle-assisted percutaneous nephrolithotomy (PCNL)?

The purpose of this study was to investigate the effectiveness and safety of flexible ureteroscopy lithotripsy (FURL) and all-seeing needle-assisted percutaneous nephrolithotomy (PCNL) for the treatment of calyceal diverticula (CD) stones. From June 2012 to November 2020, 24 patients, including 14 females and 10 males, with an average age of 45.6 ± 17.4 years were retrospectively reviewed in this study. Among these patients, 14 were treated with FURL, and 10 underwent all-seeing needle-assisted PCNL. The demographic data, perioperative parameters and complications, as well as follow-up data, were recorded. In the FURL group, the ostium of CD was not identified in two patients, and these patients were finally treated with all-seeing needle-assisted PCNL. The stone clearance rate (SCR) was 64.3%, and the mean blood loss was 0.9 ± 0.8 g/dL. The average operation time was 57.5 ± 17.4 min, and the mean hospital stay was 3.5 ± 1.4 days. A complete resolution of CD was observed in five (41.7%) patients over the average follow-up of 10.8 months. In terms of the all-seeing needle-assisted PCNL, the average operation time was 83.5 ± 32.4 min, and the mean hospital stay was 4.38 ± 2.25 days. The SCR reached 91.7%, and the blood loss was 1.7 ± 1.1 g/dL. Nine patients (75%) were observed to have complete CD resolution over an average of 12.2 months of follow-up. All complications were grade I and II in both the groups. CD stones can be treated minimally invasive and effectively by FURL and PCNL. The effect of FURL greatly depends on the location and anatomy of the diverticula. PCNL is more efficient, and its safety was improved with the help of the all-seeing needle assistance.

[Comparison of long-term outcomes in different managements of diverticular neck in percutaneous nephrolithotomy for diverticular calculi]

OBJECTIVE

To compare the short-term effects and long-term outcomes of incisional procedure and dilatation procedure to manage diverticular neck in percutaneous nephrolithotomy for diverticular stones.

METHODS

Clinical data of 61 patients with diverticular stones who underwent percutaneous nephrolithotomy from June 2009 to January 2019 were retrospectively collected and analyzed, which was as follous: (1) basic information: age, gender, body mass index (BMI), American Society of Anesthesiology (ASA) classifications and preoperative symptoms.(2)stone characteristic and procedure-related data: location and size of stone, skinned renal access length and procedure time.(3)perioperative clinical data: hemoglobin drop, Clavien's classification and stone-free rate. Long-term follow-ups were performed for more than 5 years after the patients were discharged.

RESULTS

Fifty-three patients were included based on the inclusion and exclusion criteria, and were divided into the dilation group (n=37) and the incision group (n=16) by the treatment methods of diverticular neck. There were 24 male patients (45.3%) and 29 female patients (54.7%), with a mean age of 39.96±12.88 years. Stones were mainly located in the upper pole (n=32, 60.38%) and posterior area (n=41, 77.4%), with a predominance of single stone (n=36, 67.9%). There was no statistically significant difference in demographic data and stone characteristics between the two groups except for age and stone burden. Forty-five patients (84.9%) reached stone-free status after surgeries, and 44 patients (83.0%) postoperative symptoms improved. Twelve patients were lost to the follow-ups, and 41 cases were followed up for an average of 77 months. One recurrence occurred 1 year after surgery. Fifteen patients underwent operations within the past 5 years and the overall 5-year recurrence rate for the remaining 26 patients was 34.6%. There was no statistically significant difference in the incidence of perioperative complications, postoperative stone-free rate and recurrence rate between the two groups, and the recurrence rate was significantly higher 5 years postoperatively than 1 year postoperatively. The proportion of the patients who remained lithotripsy-free and residual stone status decreased significantly.

CONCLUSION

Both incisional and dilatation procedures in percutaneous nephrolithotomy to manage diverticular neck could bring the satisfactory postoperative stone free rate. The recurrence rate was about 30% to 40% 5 years after surgery.

Effectiveness of Percutaneous Nephrolithotomy, Retrograde Intrarenal Surgery, and Extracorporeal Shock Wave Lithotripsy for Treatment of Renal Stones: A Systematic Review and Meta-Analysis

Background and objectives: To perform a updated systematic review and meta-analysis comparing effectiveness of percutaneous nephrolithotomy (PCNL), retrograde intrarenal surgery (RIRS), and extracorporeal shock wave lithotripsy (ESWL) for treatment of renal stones (RS). Materials and Methods: A total of 37 studies were included in this systematic review and meta-analysis about effectiveness to treat RS. Endpoints were stone-free rates (SFR), incidence of auxiliary procedure, retreatment, and complications. We also conducted a sub-analysis of ≥2 cm stones. Results: First, PCNL had the highest SFR than others regardless of stone sizes and RIRS showed a higher SFR than ESWL in <2 cm stones. Second, auxiliary procedures were higher in ESWL than others, and it did not differ between PCNL and RIRS. Finally, in <2 cm stones, the retreatment rate of ESWL was higher than others. RIRS required significantly more retreatment procedures than PCNL in ≥2 cm stones. Complication was higher in PCNL than others, but there was no statistically significant difference in complications between RIRS and PCNL in ≥2 cm stones. For ≥2 cm stones, PCNL had the highest SFR, and auxiliary procedures and retreatment rates were significantly lower than others. Conclusions: We suggest that PCNL is a safe and effective treatment, especially for large RS.

Effectiveness of Percutaneous Nephrolithotomy, Retrograde Intrarenal Surgery, and Extracorporeal Shock Wave Lithotripsy for Treatment of Renal Stones: A Systematic Review and Meta-Analysis

Background and objectives: To perform a updated systematic review and meta-analysis comparing effectiveness of percutaneous nephrolithotomy (PCNL), retrograde intrarenal surgery (RIRS), and extracorporeal shock wave lithotripsy (ESWL) for treatment of renal stones (RS). Materials and Methods: A total of 37 studies were included in this systematic review and meta-analysis about effectiveness to treat RS. Endpoints were stone-free rates (SFR), incidence of auxiliary procedure, retreatment, and complications. We also conducted a sub-analysis of ≥2 cm stones. Results: First, PCNL had the highest SFR than others regardless of stone sizes and RIRS showed a higher SFR than ESWL in <2 cm stones. Second, auxiliary procedures were higher in ESWL than others, and it did not differ between PCNL and RIRS. Finally, in <2 cm stones, the retreatment rate of ESWL was higher than others. RIRS required significantly more retreatment procedures than PCNL in ≥2 cm stones. Complication was higher in PCNL than others, but there was no statistically significant difference in complications between RIRS and PCNL in ≥2 cm stones. For ≥2 cm stones, PCNL had the highest SFR, and auxiliary procedures and retreatment rates were significantly lower than others. Conclusions: We suggest that PCNL is a safe and effective treatment, especially for large RS.

Actual Management of Anterior Calyceal Diverticular Calculi: A Challenging Flexible Retrograde Endoscopic Approach

Calyceal diverticula is a cavity that communicates with the collecting system through a narrow isthmus of the kidney. The incidence of the formation of stones in calyceal diverticula is 10-50%. This paper reports three cases of two females and one male who presented with calyceal diverticular calculi; the patients have been, arbitrarily, selected between August and February 2019 at the urology department of our university hospital. A minimally invasive treatment includes extracorporeal lithotripsy (ESWL), and F-URS (flexible ureteroscopy) was performed. We report this case series.

Factors Impacting Stone-Free Rate After Retrograde Intrarenal Surgery for Calyceal Diverticular Calculi

Objective

To evaluate the outcomes of retrograde intrarenal surgery (RIRS) treatment of calyceal diverticular calculi and identify the associated factors affecting post-operative stone-free rate.

Materials and Methods

From August 2015 to May 2019, data of 32 patients with calyceal diverticular calculi who were treated by RIRS in a Siriraj Hospital were retrospectively studied. All operations were performed by the same surgeon using flexible ureterorenoscopy (f-URS) and holmium YAG laser lithotripsy. Calyceal diverticula were identified by our refluxing technique and from the collected demographic, diverticular and stone data. Operative outcomes were retrospectively evaluated. Data were analysed to identify the factors associated with stone-free outcomes. Stone-free was defined as no residual stones remaining after surgery.

Results

Mean age of the patients was 55.7 years. Stone locations were non-lower pole in 81.2% of cases and lower pole for the remaining 18.8% of cases. Median stone size was 1.2 cm with three as the median number of stones per patient. Calcium oxalate was the most common stone composition (56.3%). Positions of the diverticulum were anterior calyx (34.4%) and posterior calyx (50%), while the remainder were undetermined (incomplete data). Average length of the diverticular neck was 0.4 cm. Mean operative time was 46 minutes and mean hospital stay was 2.9 days. Complications included fever in three patients (9.3%) and sepsis in two patients (6.3%), with overall post-operative stone-free rate at 75%. Factors significantly affecting stone-free status were stone size (P=0.003) and length of diverticular neck (P=0.038). Multivariate analysis determined that only stone size had a statistically significant effect on post-operative stone-free status (P=0.015). Cut off point for stone size that increased the chances of a post-operative stone-free outcome was less than 1.5 cm, as determined by the ROC curve.

Conclusion

RIRS was found to be an effective and safe treatment option for the removal of calyceal diverticular calculi. Stone size of less than 1.5 cm offered a better chance of post-operative stone-free condition.

Calyceal diverticula in children: laparoscopic marsupialization is the optimal intervention

BACKGROUND

Calyceal diverticula (CD) are abnormally dilated calyces caused by a narrowed infundibulum. Although rare, with incidence rates previously reported between 0.21% and 0.45%, CD pose diagnostic dilemmas in children as they mimic other cystic lesions of the kidney with different etiologies. Calyceal diverticula can become symptomatic if they become a locus for infections and stone formation, and the optimal treatment strategy is currently undefined.

OBJECTIVE

The aim of the study is to present a large series of consecutive cases of pediatric CD and investigate the authors' hypothesis that CDs are more common than previously reported, size of the lesion drives intervention, and laparoscopic ablation is the most effective intervention.

STUDY DESIGN

The authors conducted an observational case-control survey by reviewing all cases of pediatric CD through a prospectively maintained database of renal cystic lesions at their institution between 2012 and 2018. They analyzed the clinical and radiological presentation and description of symptoms with particular emphasis on the outcomes of ureteroscopic or laparoscopic surgical interventions.

RESULTS

Of 757 renal cysts evaluated in the pediatric urology clinics at the authors' institution, there were 43 (5%) cases of CD confirmed by cross-sectional imaging or retrograde pyelogram. The median age was 12 years. There was a female preponderance (67%), and 14% were bilateral. Twenty-five of 43 children underwent surgery (58%). On multivariate analysis, the size/complexity of the cyst (odds ratio = 2.13, 1.02 to 4.4, P = 0.04) and the presence of pain (5.931, 1.36 to 25.87, P = 0.018) were found to correlate with the need for intervention. Ureteroscopic intervention (i.e., balloon dilatation, laser incision, or diathermy incision) was the most used index procedure (17/25), followed by laparoscopic ablation (6/25), with success rates of 40% and 100%, respectively (P = 0.01). Complications in either of the approaches were usually mild and similar (P = 0.63). The majority of ureteroscopic interventions required multiple sessions (11/17, 65%, median = 2 major procedures) to achieve resolution, whereas none in the laparoscopic group required a second procedure. There were a total of 30 ureteroscopic and 8 laparoscopic approaches.

CONCLUSIONS

The authors demonstrate that CD comprise at least 5% of cystic lesions and that CD size and pain at presentation predict intervention in 60% of children diagnosed at their institution. Laparoscopic ablation is the optimal treatment and has significantly higher success rates than the ureteroscopic approach.

Treatment Options for Calyceal Diverticula

PURPOSE OF REVIEW

Calyceal diverticula are rare entities that can pose a significant challenge when it comes to their management. We analyse and summarise the literature with a focus on recent advances in the management of calyceal diverticula and discuss the advantages and disadvantages of each surgical technique.

RECENT FINDINGS

The identification of calyceal diverticula requires a certain level of suspicion and contrast-enhanced imaging. Conventional techniques of imaging the renal collecting system such as the classic intravenous urography are now superseded by the ease of access to contrast-enhanced CT imaging. Conventional surgical techniques for managing calyceal diverticula are not being superseded by new techniques but rather being progressively enhanced and improved through the amelioration of existing technology. Debate still exists over the best treatment approach for the management of symptomatic calyceal diverticula, the choice of which still very much depends on the location and anatomy of the diverticulum itself. The most significant advance in the management of calyceal diverticula and indeed stones, in general, seems to be the progressive miniaturisation of percutaneous nephrolithotomy (PCNL) equipment allowing effective treatment with a reduction in associated risks of conventional PCNL. The increasing accessibility of robotics has a role to play in the management of this condition but is not likely surpass flexible ureteroscopic (fURS) or percutaneous approaches. The future of surgical management for this condition lies in striking a balance between treatment efficacy and invasiveness. More recent identification of metabolic disturbances in patients with calyceal diverticular stones may provide further insights into the underlying pathology of this condition and is likely to play a role in future research of diverticular stones.

The Urological Association of Asia clinical guideline for urinary stone disease

The Urological Association of Asia, consisting of 25 member associations and one affiliated member since its foundation in 1990, has planned to develop Asian guidelines for all urological fields. The field of stone diseases is the third of its guideline projects. Because of the different climates, and social, economic and ethnic environments, the clinical practice for urinary stone diseases widely varies among the Asian countries. The committee members of the Urological Association of Asia on the clinical guidelines for urinary stone disease carried out a surveillance study to better understand the diversity of the treatment strategy among different regions and subsequent systematic literature review through PubMed and MEDLINE database between 1966 and 2017. Levels of evidence and grades of recommendation for each management were decided according to the relevant strategy. Each clinical question and answer were thoroughly reviewed and discussed by all committee members and their colleagues, with suggestions from expert representatives of the American Urological Association and European Association of Urology. However, we focused on the pragmatic care of patients and our own evidence throughout Asia, which included recent surgical trends, such as miniaturized percutaneous nephrolithotomy and endoscopic combined intrarenal surgery. This guideline covers all fields of stone diseases, from etiology to recurrence prevention. Here, we present a short summary of the first version of the guideline - consisting 43 clinical questions - and overview its key practical issues.

Comparison of stone-free rates following shock wave lithotripsy, percutaneous nephrolithotomy, and retrograde intrarenal surgery for treatment of renal stones: A systematic review and network meta-analysis

OBJECTIVES

To perform a systematic review and network meta-analysis comparing stone-free rates following retrograde intrarenal surgery (RIRS), extracorporeal shock wave lithotripsy (SWL), and percutaneous nephrolithotomy (PCNL) treatments of renal stones.

MATERIALS AND METHODS

Clinical trials comparing RIRS, SWL, and PCNL for treatment of renal stones were identified from electronic databases. Stone-free rates for the procedures were compared by qualitative and quantitative syntheses (meta-analyses). Outcome variables are shown as risk ratios (ORs) with 95% credible intervals (CIs).

RESULTS

A total of 35 studies were included in this network meta-analysis of success and stone-free rates following three different treatments of renal stones. Six studies compared PCNL versus SWL, ten studies compared PCNL versus RIRS, fourteen studies compared RIRS versus SWL, and five studies compared PCNL, SWL, and RIRS. The quality scores within subscales were relatively low-risk. Network meta-analyses indicated that stone-free rates of RIRS (OR 0.38; 95% CI 0.22-0.64) and SWL (OR 0.12; 95% CI 0.067-0.19) were lower than that of PCNL. In addition, stone-free rate of SWL was lower than that of RIRS (OR 0.31; 95% CI 0.20-0.47). Stone free rate of PCNL was also superior to RIRS in subgroup analyses including ≥ 2 cm stone (OR 4.680; 95% CI 2.873-8.106), lower pole stone (OR 1.984; 95% CI 1.043-2.849), and randomized studies (OR 2.219; 95% CI 1.348-4.009). In rank-probability test, PCNL was ranked as No. 1 and SWL was ranked as No. 3.

CONCLUSIONS

PCNL showed the highest success and stone-free rate in the surgical treatment of renal stones. In contrast, SWL had the lowest success and stone-free rate.

Challenges in the diagnosis of calyceal diverticulum: A report of two cases and review of the literature

BACKGROUND

Calyceal diverticula outpouchings that occur rarely in the upper collecting system of the kidney and is often difficult to detect. In this study, we present two cases of calyceal diverticula and discuss their clinical characteristics and radiologic features.

PATIENTS AND METHODS

In the presented two cases, we applied several imaging examinations, including delayed intravenous pyelography, retrograde pyelography and axial computerized tomographic (CT) scanning of the kidneys with and without contrast. Serum creatinine levels in fluid withdrawn from the diverticula were found to be significantly higher than the simultaneous serum creatinine levels. Intravenous injection of methylene blue through a ureteral catheter was also aided in the diagnosis. Calyceal diverticulum neck dilatation was performed through a percutaneous nephroscope.ResultsThe two cases were diagnosed preoperatively and the operation was successful performed. The nephrostomy tube was removed seven days after surgery without complications. CT scans of the kidney after six months showed that the size of the calyceal diverticulum of two patients were considerably smaller than pre-surgery. There were no reports of pain in the lumbar region or other discomfort.

COMMENTS

Diagnosis of calyceal diverticulum mainly depend on a variety of imaging examinations, including the delayed intravenous pyelography, retrograde pyelography, and kidney CT plain scan plus enhanced scan. If the patient cannot be diagnosed by above methods, cyst fluid can be aspirated percutaneously to measure the preoperative creatinine level. If it is significantly higher than the serum creatinine level, the cyst fluid is considered urine, which can assist in the diagnosis of calyceal diverticulum. A ureteral catheter should also be inserted before operation namely, intravenous injection of methylene blue through a ureteral catheter is helpful for diagnosis. The choice of surgical treatment is based on the size and location of calyceal diverticulum and clinical manifestations.

Rupture of a Calyceal Diverticulum Secondary to Ureteroscopy: A Rare Complication

We present a case of a 45-year-old female who experienced rupture of a right calyceal diverticulum caused by ureteroscopy. Fifteen hours after the operation, she had severe right flank pain and a high fever (38.9°C). Computed tomography revealed perinephric extravasation of urine and bleeding inside the diverticulum. We diagnosed rupture of a calyceal diverticulum; therefore, we continued antibiotic administration and pain relief medication. She became afebrile on postoperative day 4 and was discharged from the hospital on postoperative day 7. Owing to renal cortex thinning in the diverticula, ureteroscopy is associated with a risk of rupture of calyceal diverticula.

Retrograde intrarenal surgery: An expanding role in treatment of urolithiasis

During the past 3 decades, the surgical management of kidney stones has undergone many technological advances and one is the development of the flexible ureteroscopy. The development of this instrument as well as ancillary equipment such as baskets, graspers, and others, and improvements in lithotripsy with Holmium: YAG laser have led to expand its indications with diagnostic and therapeutic management of medical issues of the upper urinary tract such as urolithiasis and urothelial tumors. The objective of this review is to describe its indications and results in the different scenarios for the treatment of urinary stones.

Systematic Review of Caliceal Diverticulum

PURPOSE

We performed a systematic review of the literature regarding the diagnosis and treatment of caliceal diverticulum (CD).

METHODS

The search strategy was conducted according to the Cochrane review guidelines for systematic reviews and Preferred Reporting Items for Systematic reviews and Meta-Analyses checklist.

RESULTS

In total 1189 titles and abstracts were reviewed, of which 101 were selected for article evaluation. Of these 101 articles, 40 were selected for inclusion after full article evaluations. In the extracted article, intravenous urography (IVU), rather than CT urography, was the main imaging tool for diagnosis, although many articles had failed to provide any imaging modality information. The extracted articles included 88, 153, and 487 patients who underwent shock wave lithotripsy (SWL), flexible ureteroscopy/retrograde intrarenal surgery (fURS/RIRS), and percutaneous nephrolithotomy (PCNL), respectively. Stone-free rates were 21.3% (SWL), 61.4% (fURS/RIRS), and 83.0% (PCNL). The complication rates were 8.0% (SWL), 3.3% (fURS/RIRS), and 11.9% (PCNL). There was incomplete and inconsistent reporting of even basic clinical parameters, such as the size and location of the CD, number of stones, outcomes, and complications. There was a striking lack of follow-up data, despite a known high recurrence rate. The literature on laparoscopic management was too sparse to analyze.

CONCLUSIONS

This meta-analysis revealed that there are not enough high-quality studies to evaluate the ideal strategy for the diagnosis and treatment of CDs. This systematic review emphasizes (a) the importance of contrast imaging for CD diagnosis, (b) higher success rates but also higher complication rates in PCNL compared with SWL and FURS, and (c) the need for standardized reporting of outcomes to include complications, number of interventions, symptom resolution, stone clearance, and CD ablation.

Percutaneous Management of Stone Containing Calyceal Diverticula: Associated Factors and Outcomes

PURPOSE

We evaluated the outcomes of percutaneous treatment and metabolic evaluation of calyceal diverticula with associated stones.

MATERIALS AND METHODS

We retrospectively identified 51 patients with a calyceal diverticulum in our prospectively maintained percutaneous nephrolithotomy database. Patients with complete data were separated into 14 with stones isolated to the diverticulum and 15 with renal stones in and outside the diverticulum. A total of 571 patients with renal stones but no diverticulum were used for comparison. Statistical differences were assessed using the chi-square test and the t-test.

RESULTS

Patients with stones isolated to the diverticulum were younger (44 vs 54 years, p = 0.024), had a lower body mass index (23.2 vs 27 kg/m², p = 0.032) and were more often female (71% vs 44%, p = 0.046) compared to patients with renal stones but no diverticulum. Calyceal diverticula were anterior in 19 of 29 cases and in the upper pole in 15. Average diverticular size was 2.5 cm with a 1.5 cm stone burden. Percutaneous treatment was successful in 96% of patients with a 4% complication rate. The diverticular neck was dilated in 22 of 51 patients (43%). During 5-year followup in the 51 patients there was 1 stone recurrence, which was managed by ureteroscopy, while 46 and 5 patients showed complete absence and reduction of the diverticulum, respectively. Of the calyceal diverticular stones 82% contained calcium phosphate compared to only 33% in patients with renal stones but no diverticulum. All patients with a diverticulum had at least 1 metabolic derangement.

CONCLUSIONS

Percutaneous treatment of calyceal diverticula is safe and effective regardless of size or location, including anterior diverticula. Infundibular neck dilation does not appear to be necessary. There are metabolic abnormalities in a significant proportion of patients with a calyceal diverticulum.

Retrospective Analysis of Ultrasound-guided Flexible Ureteroscopy in the Management of Calyceal Diverticular Calculi

Background:

Percutaneous nephrolithotomy (PCNL) is the most widely recommended treatment for calyceal diverticular calculi, providing excellent stone-free results. However, its invasiveness is not negligible considering its major complication rates. Flexible ureteroscopy (FURS) is currently used to treat calyceal diverticula. However, the greatest drawback of FURS is locating the diverticulum since its neck is narrow and concealed. In such a case, the FURS procedure must be converted to PCNL. The aim of this study was to evaluate ultrasound-guided flexible ureteroscopy (UFURS) identifying diverticulum and the management of calyceal diverticular calculi.

Methods:

A retrospective analysis was conducted on 24 patients who had calyceal diverticular calculi. In all 12 patients in the UFURS group, direct FURS failed to find evidence of calyceal diverticula but were confirmed with imaging. The other 12 patients in the PCNL group received PCNL plus fulguration of the diverticular walls.

Results:

Puncture of calyceal diverticulum was successful in all 12 UFURS patients. Two patients in this group had postoperative residual calculi and two patients developed fever. In the PCNL group, percutaneous renal access and lithotomy were successful in all 12 patients. One patient in this group had residual calculi, one had perirenal hematoma, and two patients developed fever. No significant difference was found in the operating time (UFURS vs. PCNL, 91.8 ± 24.2 vs. 86.3 ± 18.7 min), stone-free rate (UFURS vs. PCNL, 9/12 vs. 10/12), and rate of successful lithotripsy (UFURS vs. PCNL, 10/12 vs. 11/12) between the two groups (all P > 0.05). Postoperative pain scores in the FURS group were significantly lower than that in the PCNL group (2.7 ± 1.2 vs. 6.2 ± 1.5, P < 0.05). Hospital stay in the UFURS group was significantly shorter than that in the PCNL group (3.4 ± 0.8 vs. 5.4 ± 1.0 days, P < 0.05). All patients were symptom-free following surgery (UFURS vs. PCNL, 10/10 vs. 12/12).

Conclusion:

Ultrasound-guided puncture facilitates identification of calyceal diverticula during FURS and improves the success rate of FURS surgery.

Management of symptomatic caliceal diverticular calculi: Minimally invasive percutaneous nephrolithotomy versus flexible ureterorenoscopy

Objective

To retrospectively evaluate appropriate treatment for patients with symptomatic caliceal diverticular calculi, by comparing the therapeutic outcomes for those undergoing minimally invasive percutaneous nephrolithotomy (MPCNL) and flexible ureterorenoscopy (F-URS).

Methods

From March 2009 to May 2014, 36 consecutive patients with caliceal diverticular calculi were divided into 2 groups: 21 patients underwent MPCNL, and 15 were treated by F-URS. All procedures were performed by one surgical group, which ensured relatively constant parameters. Patient characteristics, operative time, hospital stay after surgery, stone-free rate, symptomatic improvement rate, complications, diverticular obliteration, and stone composition were analyzed retrospectively in the 2 groups.

Results

Patient preoperative variables were comparable between the two groups, with no significant difference (P > 0.05). Mean operative time was 136.9 ± 22.8 min in the MPCNL group and 117.3 ± 24.3 min in the F-URS group (P = 0.019). Hospital stay was significantly longer in the MPCNL group than in the F-URS group (9.4 ± 3.1 vs. 6.9 ± 2.1 days, P = 0.010). The stone-free rates after MPCNL and F-URS were 90.5% (19/21) and 60.0% (9/15), respectively (P = 0.046). Additionally, 71.4% (15/21) of patients in the MPCNL group and 46.7% (7/15) of patients in the F-URS group had symptomatic improvement at the 6-month follow-up (P = 0.175); the rates of complications in the 2 groups were 19.0% (4/21) and 13.3% (2/15), respectively (P = 0.650). Complete diverticular obliteration was achieved in 16 (76.2%) cases in the MPCNL group and 5 (33.3%) cases in the F-URS group (P = 0.017). The distributions of calcium oxalate and hydroxyapatite in the stones were 66.7% (14/21) and 33.3% (7/21), respectively, in the MPCNL group; however, the distributions in the F-URS group were 46.7% (7/15) and 53.3% (8/15), respectively (P = 0.310).

Conclusion

MPCNL is an effective method for the treatment of caliceal diverticular calculi. However, F-URS is an alternative technique in selected patients with a patent infundibulum, despite lower stone-free rates than with MPCNL. Fulguration of the diverticular lining with a high-power holmium laser and permitting the cavity to collapse are useful to increase the chance of diverticular obliteration.

Effects of Parenchymal Thickness and Stone Density Values on Percutaneous Nephrolithotomy Outcomes

BACKGROUND It is unclear whether parenchymal thickness (PT), in combination with stone density measured by Hounsfield Units (HU), affects stone-free rates after PCNL. The aim of the present study was to investigate the relationship between PT in combination with stone density values and the outcomes of PCNL. MATERIAL AND METHODS From 2009 to 2014, data from 216 PCNL patients were prospectively analyzed. In total, 120 patients were included in the study. Using NCCT images, stone burden, stone localization, stone density as HU values, PT, and operative-postoperative parameters were recorded. RESULTS Stone localization, stone type, stone burden, and presence of hydronephrosis were statistically significant factors affecting stone-free status (p<0.001, p<0.001, p<0.01, and p<0.01, respectively). The stone-free rate in patients with thicker renal parenchyma was higher than in patients with lower parenchymal thickness (p<0.01). No correlation was detected between stone density and success rate (p>0.05). Drop in Hb (%) was only correlated with parenchymal thickness (p<0.01). In univariate analyses, factors that affected blood transfusion requirement were PT, BMI, and operative times (p<0.01, p<0.05, and p<0.05, respectively). CONCLUSIONS Stone location, stone burden, and presence of hydronephrosis detected with NCCT were factors affecting PCNL outcome. Stone density values did not correlate with the rate of bleeding or success of PCNL. PT measured by NCCT may predict bleeding and may guide surgeons in determining preoperative blood requirements. The outcome of PCNL appeared to be better in patients with thicker renal parenchyma and should be taken into consideration in the clinical evaluation of patients undergoing PCNL.

Factors affecting complication rates of retrograde flexible ureterorenoscopy: analysis of 1571 procedures-a single-center experience

PURPOSE

To evaluate the factors affecting complication rates of flexible ureteroscopy and laser lithotripsy (FURSL).

MATERIALS AND METHODS

Data on a total of 1395 patients, with 1411 renal units underwent 1571 procedures with FURSL for renal and/or proximal ureteral stones between April 2012 and January 2016, were retrospectively analyzed. Complications were assessed using the Satava and modified Clavien systems. Univariate and multivariate analyses were done to determine predictive factors affecting complication rates.

RESULTS

The mean patient age in the total procedures was 45.68 ± 14.00 years (range 2-86 years), and the mean stone size was 15.15 ± 8.32 mm (range 5-75 mm). The overall success rate was 95.6 %. A total of 209 (13.3 %) cases suffered from complications with intraoperative complications rates of 5.9 % and postoperative complication rates of 7.3 %. Univariate analysis revealed no significant difference in complication rates in respect of age, gender, body mass index, use of ureteral access sheath, operation time, bleeding disorder, solitary kidney, preoperative stenting, American Society of Anesthesiologists score, repeated procedure or location of stones (all p value >0.05). Complication rates were determined to be significantly affected by stone size (p = 0.026), multiplicity (p = 0.028) and the presence of congenital renal abnormality (p < 0.01). The only significant factor in multivariate analysis was the presence of congenital renal abnormalities (p = 0.02).

CONCLUSIONS

The results of the current study indicated that stone size, stone number and the presence of congenital renal abnormalities were factors affecting complication rates after FURSL, although congenital renal abnormality was the only independent predictor among these risk factors.

Retrograde intrarenal surgery in the management of symptomatic calyceal diverticular stones: a single center experience

To evaluate the outcome of RIRS in managing symptomatic calyceal diverticular as a minimally invasive option, we retrospectively reviewed the records of 43 patients who underwent RIRS from 2005 to 2014 for symptomatic calyceal diverticular stones. A month after the initial operation, the success rate was (81.4%, 35 patients) of which 21 (48.83%) patients were stone free and 14 (32.6%) patients had clinically insignificant residual fragments (CIRFs), and 90% patients were symptom free. Eight patients (16.6%) had significant residual fragments (>3 mm), five of them became completely stone free after the second procedure, other three patients were symptom free and underwent a routine follow-up. The final treatment success rate was 93.0%. The initial success rate in the lower calyx was significantly lower than the other calices (P = 0.040). In addition, the association between the stone size and the initial treatment success was significant (P = 0.036). There was no association between any of our other variables and the success rate. The mean first operative time was 60.95 ± 12.43 min (range 34-92). No major complication (Clavien III-V) occurred, although there were five minor complications (11.6%) (Clavien I-II). There were no admissions to intensive care or deaths in our series, the mean hospitalization time was 1.77 ± 0.80 days. The management of calyceal diverticular calculus with RIRS is highly effective and can be accomplished with low morbidity.