Journal of Pediatric Urology (2015) 11, 172.e1e172.e6
Pediatric calyceal diverticulum treatment: An experience with endoscopic and laparoscopic approaches C.J. Long, D.A. Weiss, T.F. Kolon, A.K. Srinivasan, A.R. Shukla The John W. Duckett Center for Pediatric Urology at the Children’s Hospital of Philadelphia, Philadelphia, PA, USA Correspondence to: C.J. Long, Perelman School of Medicine at the University of Pennsylvania, Division of Urology, The Children’s Hospital of Philadelphia, 3rd Floor, Wood Center, 34th Street and Civic Center Blvd, Philadelphia, Pennsylvania 19104, USA, Tel.: þ1 215 590 2754; fax: þ1 267 426 7335 [email protected] (C.J. Long) [email protected] (D.A. Weiss) [email protected] (T.F. Kolon) srinivasana3@email. chop.edu (A.K. Srinivasan) [email protected] (A.R. Shukla) Keywords Pediatric urology; Calyceal diverticulum; Minimally invasive surgery; Ureteroscopy; Laparoscopy Received 6 January 2015 Accepted 23 April 2015 Available online 21 May 2015
Introduction The symptomatic calyceal diverticulum is a rare event in the pediatric population. In adults, surgical options include ureteroscopy, percutaneous ablation, and laparoscopic decortication but there is a lack of experience in the literature with these techniques. Objective We present our experience with both the ureteroscopic and laparoscopic approach to treating the pediatric calyceal diverticulum. Study design We performed a retrospective case series looking at patients who underwent treatment for calyceal diverticulum at our institution from January 2009 to May 2014. We reviewed patient demographics, indications for intervention, radiographic appearance, type of intervention, and perioperative outcomes. Ureteroscopic approach included dilation of infundibulum and ablation of diverticular cavity. Laparoscopic approach included ablation of the diverticulum with argon diathermy with or without surgical closure of the ostium. Results There were 13 patients who underwent 15 procedures for symptomatic calyceal diverticulum (Table). Median age was 11 years. Indications for intervention were: pain and increasing size of diverticulum (8/15, 55%), hematuria (3/15, 20%), UTI (3/15, 20%), and calculi (1/15, 5%). 11/15 (73%) procedures were managed endoscopically and 4/15
Table
(27%) were managed with laparoscopic decortication. Ureteral stent was left in all patients for a mean duration of 51 days (15e120 days). Follow up imaging at median of 2.1 years (0.5e4 years) revealed an initial success rate of 85% (11/13 patients). Two patients failed initial intervention (persistent pain/increasing size) necessitating successful secondary minimally invasive procedures. There were 2 (13%) complications: a perinephric hematoma post endoscopic ablation which resolved spontaneously and a deep venous thrombosis in a patient with a coagulation disorder in the laparoscopic group. Discussion Limitations of our study include its retrospective design, lack of standardization of the treatment approach amongst the four treating surgeons, and the small number of patients requiring intervention for this relatively rare diagnosis. Our study is the largest to date in the pediatric population and is the first to report outcomes with ureteroscopic management of the calyceal diverticulum. Conclusions We found that the pediatric calyceal diverticulum can be successfully treated in a minimally invasive manner. The endoscopic approach should be the first line option for patients with small, endophytic diverticula, particularly those located in the upper and mid pole. The laparoscopic approach is more invasive but should be considered for large diverticula that are exophytic with thin overlying parenchyma.
Summary of patient data. Complications classified according to clavien-dindo system.
Number of patients Size: median cm (range) Median decrease in size (cm) Median OR time, minutes (range) Median length of stay, days (range) Failure of initial therapy Complications
Endoscopic
Laparoscopic
9/13 (73%) 2.3 (1.3e3.5) 1.0 (0e2) 69 (13e97) 0.25 (0.2e1.2) 2/9 Repeat procedure 2 (Clavien IIIb) Perinephric hematoma 1 (Clavien I)
4/13 (27%) 5.8 (2e10) 3.0 (2.4e7.2) 172 (107e197) 2 (1.9e4) 0/4 DVT 1 (Clavien II)
http://dx.doi.org/10.1016/j.jpurol.2015.04.013 1477-5131/ª 2015 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.
Pediatric calyceal diverticulum treatment
Introduction A calyceal diverticulum is an outpouching of the collecting system, which is lined with transitional epithelium that is non-secretory [1,2]. The connection with the collecting system allows passive filling and the cavity can enlarge due to narrowing of the infundibulum and urine stasis, which can result in stone formation and infection. The exact etiology of calyceal diverticulum development is unknown, but it is thought to be either congenital due to ureteric bud regression failure or secondary to an inflammatory or obstructive process in response to infection or reflux [1,3,4]. Two anatomic types have been described in the literature: Type 1 is more common, arising from a minor calyx and more likely to be asymptomatic lying in the polar region of the kidney; Type 2 arises directly from the renal pelvis or major calyx and the diverticular are more likely to be larger in size and symptomatic [2]. Although a rare entity [1,4,5], surgical intervention is warranted when the patient presents with symptoms including pain, stones, infection, and increasing size. Methods of intervention in the adult literature include endoscopic, laparoscopic, and open approaches [6,7]. Extracorporeal shock wave lithotripsy and open surgery have been surpassed by other more-effective minimally invasive techniques [8]. The endoscopic approaches include either retrograde ureteroscopy, direct percutaneous ablation [7,9e11] or a combination of the two [12]. Direct percutaneous ablation is accomplished in a similar manner to percutaneous nephrolithotripsy (PCNL), with stone removal, if needed, and ablation of the diverticulum cavity [9]. The ureteroscopic approach can be utilized if the tract to the diverticulum is accessible in a retrograde fashion. Postoperative management typically includes an internal ureteral stent. Laparoscopic or open intervention involves removal of the wall or roof of the diverticulum and closure of the neck or infundibulum by fulguration or suture ligation [13,14]. Postoperative management typically includes bladder drainage with a Foley catheter, a ureteral stent, and a perinephric drain in the laparoscopic approach. To date, calyceal diverticulum management in the pediatric literature is limited to two studies utilizing the laparoscopic, open, and PCNL approaches [5,14]. There is no consensus within the pediatric literature regarding ideal calyceal diverticulum management and no experience with the ureteroscopic approach. The present study hypothesized that pediatric calyceal diverticulum can be successfully treated with minimally invasive surgery. Herein, experience with the endoscopic and laparoscopic approaches is presented.
Materials and methods The prospective, internal-review-board-approved database was searched to identify patients who had undergone treatment for calyceal diverticulum from January 2009 to May 2014. Demographic information including age, sex, and laterality were recorded. Indications for intervention included pain, increasing size of diverticulum, stones within the diverticulum, hematuria, and infection. Pre-
172.e2 operative imaging included renal bladder ultrasound (RBUS), magnetic resonance urography (MRU), and/or CT urography (CTU). Diverticula were characterized by polarity (upper, mid, lower pole) and degree of endophycity, which was defined as 50% outside the border of the kidney (exophytic). At the time of intervention all procedures began with a retrograde pyelogram to confirm the presence of a calyceal diverticulum (if no CTU or MRU was performed pre-operatively) and to place a ureteral stent. If no connection with the collecting system was identified, the lesion was treated as a simple cyst and was treated with laparoscopic decortication, if symptoms warranted intervention. Either a ureteroscopic or laparoscopic approach was used to treat the calyceal diverticulum. The antegrade percutaneous approach was not used as it is felt that this is an inferior approach compared to URS and laparoscopic intervention [5]. The ureteroscopic approach was as follows: a cystoscopy and retrograde pyelogram were performed to delineate the anatomy, including the location and length of the diverticular infundibulum. A soft-tip wire was passed directly into the diverticulum (if feasible) and balloon dilation of the tract was performed. When unable to pass the wire directly into the lumen due to a narrow infundibulum, an initial attempt was made under direct vision with the ureteroscope. If the lumen was too narrow, the tract was incised with the holmium laser. Once sufficiently dilated, an 8-Fr flexible ureteroscope was then advanced into the diverticulum and the cavity was ablated with either cautery or the holmium laser. After dilation and ablation, one or two double J stents were left across the dilated tract and removed 2e8 weeks later (at the present institution the median stent duration was 45 days). For younger children, a 4.6-Fr ureteral stent was used, while in adolescents, a 6-Fr ureteral stents was used. The decision to place two ureteral stents was based upon the capacity of the tract and ureter to accommodate increased stent size; the preference at the present institution was to place two stents, if possible. The laparoscopic approach was performed via both traditional and single port techniques. Prior to obtaining laparoscopic access, a retrograde pyelogram was performed to confirm the presence of a calyceal diverticulum and to localize the infundibulum. An internal double J stent was left in the renal pelvis. Patients were placed in the flank position and access was obtained via the Hasson technique for both approaches. Single port access was within the umbilicus and the entire procedure was performed via this port. For traditional laparoscopy, subxiphoid and ipsilateral lower abdominal ports were placed in addition to the umbilical port. Once the kidney was exposed, the roof of the diverticulum was incised and, if visible, the neck of the infundibulum was either sutured closed or fulgurated. The bed of the diverticulum was then ablated with the argon beam, and a perinephric drain was left in place. Postoperatively, the Foley catheter was removed when minimal drain output was noted, and the internal double J stent was removed 2e8 weeks post excision (median stent duration was 41 days). If the perinephric drain demonstrated a urine leak after Foley catheter
172.e3 removal, the catheter was replaced until the drain output became negligible. Follow-up imaging consisted of renal bladder ultrasound and either CTU or MRU if concern was present for a recurrent diverticulum. Complications were graded according to the Clavien-Dindo classification system [15]. Successful diverticulum management was defined as resolution of symptoms necessitating repair. The objective of this retrospective case series was to report the present institution’s approach to treatment of symptomatic calyceal diverticulum with both the ureteroscopic and laparoscopic approach. The aim was to determine factors that contribute to outcomes and to determine the anticipated postoperative course.
C.J. Long et al. Table 1 Demographics of all patients undergoing calyceal diverticulectomy at the institution from 2009 to 2014. Demographics Number of patients Number of procedures Sex Median age, years (range) Median size of diverticulum, cm (range) Laterality
13 15 Male 7/13 (54%) Female 6/13 (46%) 11 (2e17) 2.3 (1.2e10) Left 9/13 (69%) Right 4/13 (31%)
Results Of the 15 procedures performed on 13 children in the study cohort, 11 (73%) and four (37%) procedures were endoscopic and laparoscopic, respectively (Table 1). There were seven males and six females. The age of the cohort ranged from 2 to 17 years. The size of the calyceal diverticulum ranged from 1.2 to 10 cm with a median diameter of 2.3 cm. Indications for intervention included: pain or increasing size in 8/15 (55%), UTI in 3/15 (20%), hematuria in 3/15 (20%), and stones in 1/15 (5%) (Table 2). A total of 9/10 (90%) endophytic diverticula were treated endoscopically (Table 3). The one lower pole endophytic lesion was approached laparoscopically. The median stent duration in the endoscopic group was 45 days compared to 41 days in the laparoscopic group. While symptomatic relief was obtained in 11/13 (85%) patients initially undergoing surgery, complete radiographic resolution of the diverticulum occurred in 75% and 27% of laparoscopic and endoscopic repairs, respectively. The median postoperative decrease in diverticulum size was 1.0 cm in the endoscopic group and 3.0 cm in the laparoscopic group. The median operative time in the ureteroscopy group was 69 min (range 12e97) compared to 172 min (range 107e197) in the laparoscopic group. The length of stay was a median of 2 days in the laparoscopic group, compared to 0.25 days in the endoscopic group (Table 3). Two patients required re-operation for failed primary intervention (Table 3). Both failures were in the endoscopic group and were initially treated with laser incision of the infundibulum. Both were subsequently successfully retreated endoscopically: one with repeat laser incision alone and the other with balloon dilation with laser incision, for an overall success rate of 100%. The first patient had recurrent hematuria and an increase in size of a previously treated diverticulum 4 years after treatment. The infundibulum was scarred and narrow, but responded well to balloon dilation, laser incision and double stenting. The second patient underwent endoscopic intervention, but a wire could not be passed into the diverticulum during the initial operation and a failed attempt at laser incision of the infundibulum. The patient was rescheduled for a planned laparoscopic ablation; however, during the cystoscopy and retrograde pyelogram with stent placement at the start of surgery, the infundibulum accommodated the wire and ultimately the endoscopic approach was utilized.
Table 2 Indications for surgical intervention (including two re-operations). Indications
Number of patients (%)
Pain/increasing size UTI Hematuria Stones
8/15 3/15 3/15 1/15
(55%) (20%) (20%) (5%)
Discussion Pediatric calyceal diverticulum is a relatively rare entity, and the present cohort of patients and subsequent surgical management is the largest, to date, in the pediatric literature. In the present study, the techniques and experience utilizing ureteroscopy and laparoscopy to treat pediatric calyceal diverticulum have been presented. The experience reflects the interventions that are predicated for best practice, and an incorporation of techniques routinely applied for adult calyceal diverticulum management. Diagnosis of calyceal diverticulum is first suspected when a hypoechoic defect is seen within the kidney on a renal and bladder ultrasound, particularly when stones are present or there is an increase in size of the defect on subsequent studies. Diagnosis of calyceal diverticulum should be confirmed or ruled out with a contrast study. It is preferable to use MRU, due to the inherent necessity of significant radiation exposure in a CTU, particularly with the concerns about the impact of radiation upon the pediatric population. Alternatively, if a contrast study cannot be performed, a retrograde pyelogram in the operating room can confirm the presence of a communication with the collecting system. It can also provide a roadmap in the operating room by identifying the location of the infundibulum. Review of the adult literature provides comparison amongst the different treatment modalities for calyceal diverticula. Bas et al. found no significant difference in overall success rate for PCNL and URS (83% vs 76%, P Z 0.539), defined by symptom- and stone-free rates [6]. They did note a significant increase in major complications in the PCNL group due to its more invasive nature, and also noted that PCNL was able to address a larger overall stone burden. Auge et al. also compared PCNL and URS, finding PCNL superior at clearing increased stone burdens e but
Pediatric calyceal diverticulum treatment Table 3
172.e4
Summary of perioperative parameters: utilized approaches included endoscopy and laparoscopy.
Number of patients Location Endophytic Upper pole Mid pole Lower pole Exophytic Upper pole Mid pole Lower pole Size, median cm (range) Laterality, left, N Median decrease in size, cm (range) Complete resolution, N (%) No change, N (%) Improved, N (%) Median OR time, minutes (range) Median length of stay, days (range) Failure of initial therapy, N Stent duration, median days (range) Complications
Endoscopic
Laparoscopic
9/13 (73%)
4/13 (27%)
7 1 1
0 0 1
0 0 0 2.3 (1.3e3.5) 7/9 1.0 (0e2) 3/9 (33%) 3/9 (33%) 3/9 (33%) 69 (13e97) 0.25 (0.2e1.2) 2/9 45 (29e90) Repeat procedure 2 (Clavien III b) Perinephric hematoma 1 (Clavien I)
2 1 0 5.8 (2e10) 2/4 3.0 (2.4e7.2) 3/4 (75%) 0 (0%) 1/4 (25%) 172 (107e197) 2 (1.9e4) 0/4 41 (15e120) Deep vein thrombosis 1 (Clavien II)
with a higher complication rate [16]. The authors suggest that the percutaneous approach is ideal for posterior lesions and those with large stone burdens, at least compared to URS. Overall success rates of the PCNL approach range from 54 to 100% in the published literature [17]. Overall success rates for entry into and ablation of diverticulum via ureteroscopy range from 76 to 100% [7,10,16,17]. Finally, the laparoscopic approach results in overall success rates ranging from 66 to 100%, albeit using the most-invasive approach compared to URS or PCNL [13,17,18]. Casale et al. presented experience with laparoscopic diverticulectomy in three pediatric patients. They noted a 100% success rate with no complications [14]. All diverticula were Type 2 and were identified by retrograde pyelogram at the start of the procedure. All lesions were on the anteromedial portion of the kidney and were approached transperitoneally. The authors were able to identify and suture ligate the infundibulum in all patients. Urethral, ureteral, and perinephric drains were all removed on postoperative day 1. Estrada el al. operated on 10/23 (43%) patients who were identified as having calyceal diverticula at their institution from 1983 to 2006 [5]. Their initial procedure of choice was percutaneous ablation, but over the course of the inclusion period this had evolved to laparoscopic marsupialization. At a mean follow-up of 3.1 years there were no complications and a 100% success rate. The percutaneous approach was accomplished with direct access into the diverticulum, dilation of the tract into the renal pelvis, and obliteration of the cavity with electrocautery. The infundibulum of the tract was cauterized as well. Laparoscopically, the diverticulum was marsupialized, fulgurated, and filled with perinephric fat. A perinephric drain was left in place for 1e2 days.
The present study demonstrated an overall success rate of 100%, with two patients requiring repeat intervention for initial failure. This study is the first to report success with the ureteroscopic approach for treatment of calyceal diverticulum in the pediatric population. Endophytic lesions were found, which were unlikely to be visible on the surface of the kidney, located at the mid to upper pole and ideal for endoscopic ablation. One endophytic, lower-pole lesion was approached laparoscopically as it was believed that the anatomical location would limit scope deflection and, hence, the ability to successfully treat the diverticulum. Balloon dilation of the infundibular tract was performed when the tract was large enough to accommodate passage of the balloon over an appropriate guide wire. When the tract was too small to pass the balloon, the holmium laser was used to incise the tract to allow for scope passage. The tract was then further dilated with the balloon, if not sufficiently done so with the laser. The cavity was then ablated with electrocautery or the holmium laser. Postoperatively, it was preferred to place two double J stents across the infundibulum directly into the cavity in order to prevent collapse of the dilated tract, although double stenting was not feasible in all patients. Although complete radiographic resolution occurred in 3/9 (33%) endoscopically treated patients, symptoms resolved in all e two were after repeat endoscopic ablation. Of note: 3/9 (33%) endoscopically treated patients had no discernable change in radiographic appearance. The one patient in the cohort with a stone localized within a diverticulum was successfully treated via the ureteroscopic approach. As expected, the laparoscopic approach had longer median operative times (172 vs 69 min) and median length of stay (2 vs 0.25 days).
172.e5 Technical considerations for the ureteroscopic approach included the following: stent size was determined based upon the safest allowable size that could be accommodated by the ureter and infundibulum. If the ureter would not accommodate scope passage, passive ureteral dilation with internal stenting and a staged approach was preferentially performed, as opposed to active coaxial ureteral dilation. A double-stenting technique was preferred, when possible, to maximally dilate the infundibulum. It was felt that the presence of the ureteral stent into the diverticulum facilitated healing of the tract to maintain patency. When utilizing the laparoscopic approach, suturing the infundibular tract is recommended to prevent a prolonged urinary leak after diverticulectomy. Alternatively, patients can be counseled that internal ureteral stenting and Foley catheter utilization can aid repair, albeit with prolonged catheter placement. The laparoscopic approach was performed for exophytic (3/4 patients) or lower pole (1/4) lesions. It is believed that this is the first description of pediatric single port calyceal diverticulectomy (2/4 patients). It is preferable to leave a perinephric drain, an internal double J stent, and a Foley catheter in situ after the procedure. Length of time maintaining a ureteral stent and urethral catheterization are dependent upon the output recorded in the perinephric drain. One patient required a Foley catheter for 1 week due to persistent perinephric drain output suggesting a persistent urine leak; the leak resolved spontaneously. Of note: the infundibulum was not sutured on this patient and this resulted in a change in future postoperative practice. Radiographic improvement was more pronounced in the laparoscopic group compared to the URS group, although complete symptom resolution was noted in all patients. Although previous reports have identified a strong concordance of VUR and pediatric diverticulum [19], and as the management of VUR has evolved in the field of pediatric urology, VCUG studies are not routinely performed at the present institution. In the present study, 2/13 (15%) patients diagnosed with a UTI underwent VCUG in addition to US for UTI workup. These patients were young (
Pediatric calyceal diverticulum treatment: An experience with endoscopic and laparoscopic approaches C.J. Long, D.A. Weiss, T.F. Kolon, A.K. Srinivasan, A.R. Shukla The John W. Duckett Center for Pediatric Urology at the Children’s Hospital of Philadelphia, Philadelphia, PA, USA Correspondence to: C.J. Long, Perelman School of Medicine at the University of Pennsylvania, Division of Urology, The Children’s Hospital of Philadelphia, 3rd Floor, Wood Center, 34th Street and Civic Center Blvd, Philadelphia, Pennsylvania 19104, USA, Tel.: þ1 215 590 2754; fax: þ1 267 426 7335 [email protected] (C.J. Long) [email protected] (D.A. Weiss) [email protected] (T.F. Kolon) srinivasana3@email. chop.edu (A.K. Srinivasan) [email protected] (A.R. Shukla) Keywords Pediatric urology; Calyceal diverticulum; Minimally invasive surgery; Ureteroscopy; Laparoscopy Received 6 January 2015 Accepted 23 April 2015 Available online 21 May 2015
Introduction The symptomatic calyceal diverticulum is a rare event in the pediatric population. In adults, surgical options include ureteroscopy, percutaneous ablation, and laparoscopic decortication but there is a lack of experience in the literature with these techniques. Objective We present our experience with both the ureteroscopic and laparoscopic approach to treating the pediatric calyceal diverticulum. Study design We performed a retrospective case series looking at patients who underwent treatment for calyceal diverticulum at our institution from January 2009 to May 2014. We reviewed patient demographics, indications for intervention, radiographic appearance, type of intervention, and perioperative outcomes. Ureteroscopic approach included dilation of infundibulum and ablation of diverticular cavity. Laparoscopic approach included ablation of the diverticulum with argon diathermy with or without surgical closure of the ostium. Results There were 13 patients who underwent 15 procedures for symptomatic calyceal diverticulum (Table). Median age was 11 years. Indications for intervention were: pain and increasing size of diverticulum (8/15, 55%), hematuria (3/15, 20%), UTI (3/15, 20%), and calculi (1/15, 5%). 11/15 (73%) procedures were managed endoscopically and 4/15
Table
(27%) were managed with laparoscopic decortication. Ureteral stent was left in all patients for a mean duration of 51 days (15e120 days). Follow up imaging at median of 2.1 years (0.5e4 years) revealed an initial success rate of 85% (11/13 patients). Two patients failed initial intervention (persistent pain/increasing size) necessitating successful secondary minimally invasive procedures. There were 2 (13%) complications: a perinephric hematoma post endoscopic ablation which resolved spontaneously and a deep venous thrombosis in a patient with a coagulation disorder in the laparoscopic group. Discussion Limitations of our study include its retrospective design, lack of standardization of the treatment approach amongst the four treating surgeons, and the small number of patients requiring intervention for this relatively rare diagnosis. Our study is the largest to date in the pediatric population and is the first to report outcomes with ureteroscopic management of the calyceal diverticulum. Conclusions We found that the pediatric calyceal diverticulum can be successfully treated in a minimally invasive manner. The endoscopic approach should be the first line option for patients with small, endophytic diverticula, particularly those located in the upper and mid pole. The laparoscopic approach is more invasive but should be considered for large diverticula that are exophytic with thin overlying parenchyma.
Summary of patient data. Complications classified according to clavien-dindo system.
Number of patients Size: median cm (range) Median decrease in size (cm) Median OR time, minutes (range) Median length of stay, days (range) Failure of initial therapy Complications
Endoscopic
Laparoscopic
9/13 (73%) 2.3 (1.3e3.5) 1.0 (0e2) 69 (13e97) 0.25 (0.2e1.2) 2/9 Repeat procedure 2 (Clavien IIIb) Perinephric hematoma 1 (Clavien I)
4/13 (27%) 5.8 (2e10) 3.0 (2.4e7.2) 172 (107e197) 2 (1.9e4) 0/4 DVT 1 (Clavien II)
http://dx.doi.org/10.1016/j.jpurol.2015.04.013 1477-5131/ª 2015 Journal of Pediatric Urology Company. Published by Elsevier Ltd. All rights reserved.
Pediatric calyceal diverticulum treatment
Introduction A calyceal diverticulum is an outpouching of the collecting system, which is lined with transitional epithelium that is non-secretory [1,2]. The connection with the collecting system allows passive filling and the cavity can enlarge due to narrowing of the infundibulum and urine stasis, which can result in stone formation and infection. The exact etiology of calyceal diverticulum development is unknown, but it is thought to be either congenital due to ureteric bud regression failure or secondary to an inflammatory or obstructive process in response to infection or reflux [1,3,4]. Two anatomic types have been described in the literature: Type 1 is more common, arising from a minor calyx and more likely to be asymptomatic lying in the polar region of the kidney; Type 2 arises directly from the renal pelvis or major calyx and the diverticular are more likely to be larger in size and symptomatic [2]. Although a rare entity [1,4,5], surgical intervention is warranted when the patient presents with symptoms including pain, stones, infection, and increasing size. Methods of intervention in the adult literature include endoscopic, laparoscopic, and open approaches [6,7]. Extracorporeal shock wave lithotripsy and open surgery have been surpassed by other more-effective minimally invasive techniques [8]. The endoscopic approaches include either retrograde ureteroscopy, direct percutaneous ablation [7,9e11] or a combination of the two [12]. Direct percutaneous ablation is accomplished in a similar manner to percutaneous nephrolithotripsy (PCNL), with stone removal, if needed, and ablation of the diverticulum cavity [9]. The ureteroscopic approach can be utilized if the tract to the diverticulum is accessible in a retrograde fashion. Postoperative management typically includes an internal ureteral stent. Laparoscopic or open intervention involves removal of the wall or roof of the diverticulum and closure of the neck or infundibulum by fulguration or suture ligation [13,14]. Postoperative management typically includes bladder drainage with a Foley catheter, a ureteral stent, and a perinephric drain in the laparoscopic approach. To date, calyceal diverticulum management in the pediatric literature is limited to two studies utilizing the laparoscopic, open, and PCNL approaches [5,14]. There is no consensus within the pediatric literature regarding ideal calyceal diverticulum management and no experience with the ureteroscopic approach. The present study hypothesized that pediatric calyceal diverticulum can be successfully treated with minimally invasive surgery. Herein, experience with the endoscopic and laparoscopic approaches is presented.
Materials and methods The prospective, internal-review-board-approved database was searched to identify patients who had undergone treatment for calyceal diverticulum from January 2009 to May 2014. Demographic information including age, sex, and laterality were recorded. Indications for intervention included pain, increasing size of diverticulum, stones within the diverticulum, hematuria, and infection. Pre-
172.e2 operative imaging included renal bladder ultrasound (RBUS), magnetic resonance urography (MRU), and/or CT urography (CTU). Diverticula were characterized by polarity (upper, mid, lower pole) and degree of endophycity, which was defined as 50% outside the border of the kidney (exophytic). At the time of intervention all procedures began with a retrograde pyelogram to confirm the presence of a calyceal diverticulum (if no CTU or MRU was performed pre-operatively) and to place a ureteral stent. If no connection with the collecting system was identified, the lesion was treated as a simple cyst and was treated with laparoscopic decortication, if symptoms warranted intervention. Either a ureteroscopic or laparoscopic approach was used to treat the calyceal diverticulum. The antegrade percutaneous approach was not used as it is felt that this is an inferior approach compared to URS and laparoscopic intervention [5]. The ureteroscopic approach was as follows: a cystoscopy and retrograde pyelogram were performed to delineate the anatomy, including the location and length of the diverticular infundibulum. A soft-tip wire was passed directly into the diverticulum (if feasible) and balloon dilation of the tract was performed. When unable to pass the wire directly into the lumen due to a narrow infundibulum, an initial attempt was made under direct vision with the ureteroscope. If the lumen was too narrow, the tract was incised with the holmium laser. Once sufficiently dilated, an 8-Fr flexible ureteroscope was then advanced into the diverticulum and the cavity was ablated with either cautery or the holmium laser. After dilation and ablation, one or two double J stents were left across the dilated tract and removed 2e8 weeks later (at the present institution the median stent duration was 45 days). For younger children, a 4.6-Fr ureteral stent was used, while in adolescents, a 6-Fr ureteral stents was used. The decision to place two ureteral stents was based upon the capacity of the tract and ureter to accommodate increased stent size; the preference at the present institution was to place two stents, if possible. The laparoscopic approach was performed via both traditional and single port techniques. Prior to obtaining laparoscopic access, a retrograde pyelogram was performed to confirm the presence of a calyceal diverticulum and to localize the infundibulum. An internal double J stent was left in the renal pelvis. Patients were placed in the flank position and access was obtained via the Hasson technique for both approaches. Single port access was within the umbilicus and the entire procedure was performed via this port. For traditional laparoscopy, subxiphoid and ipsilateral lower abdominal ports were placed in addition to the umbilical port. Once the kidney was exposed, the roof of the diverticulum was incised and, if visible, the neck of the infundibulum was either sutured closed or fulgurated. The bed of the diverticulum was then ablated with the argon beam, and a perinephric drain was left in place. Postoperatively, the Foley catheter was removed when minimal drain output was noted, and the internal double J stent was removed 2e8 weeks post excision (median stent duration was 41 days). If the perinephric drain demonstrated a urine leak after Foley catheter
172.e3 removal, the catheter was replaced until the drain output became negligible. Follow-up imaging consisted of renal bladder ultrasound and either CTU or MRU if concern was present for a recurrent diverticulum. Complications were graded according to the Clavien-Dindo classification system [15]. Successful diverticulum management was defined as resolution of symptoms necessitating repair. The objective of this retrospective case series was to report the present institution’s approach to treatment of symptomatic calyceal diverticulum with both the ureteroscopic and laparoscopic approach. The aim was to determine factors that contribute to outcomes and to determine the anticipated postoperative course.
C.J. Long et al. Table 1 Demographics of all patients undergoing calyceal diverticulectomy at the institution from 2009 to 2014. Demographics Number of patients Number of procedures Sex Median age, years (range) Median size of diverticulum, cm (range) Laterality
13 15 Male 7/13 (54%) Female 6/13 (46%) 11 (2e17) 2.3 (1.2e10) Left 9/13 (69%) Right 4/13 (31%)
Results Of the 15 procedures performed on 13 children in the study cohort, 11 (73%) and four (37%) procedures were endoscopic and laparoscopic, respectively (Table 1). There were seven males and six females. The age of the cohort ranged from 2 to 17 years. The size of the calyceal diverticulum ranged from 1.2 to 10 cm with a median diameter of 2.3 cm. Indications for intervention included: pain or increasing size in 8/15 (55%), UTI in 3/15 (20%), hematuria in 3/15 (20%), and stones in 1/15 (5%) (Table 2). A total of 9/10 (90%) endophytic diverticula were treated endoscopically (Table 3). The one lower pole endophytic lesion was approached laparoscopically. The median stent duration in the endoscopic group was 45 days compared to 41 days in the laparoscopic group. While symptomatic relief was obtained in 11/13 (85%) patients initially undergoing surgery, complete radiographic resolution of the diverticulum occurred in 75% and 27% of laparoscopic and endoscopic repairs, respectively. The median postoperative decrease in diverticulum size was 1.0 cm in the endoscopic group and 3.0 cm in the laparoscopic group. The median operative time in the ureteroscopy group was 69 min (range 12e97) compared to 172 min (range 107e197) in the laparoscopic group. The length of stay was a median of 2 days in the laparoscopic group, compared to 0.25 days in the endoscopic group (Table 3). Two patients required re-operation for failed primary intervention (Table 3). Both failures were in the endoscopic group and were initially treated with laser incision of the infundibulum. Both were subsequently successfully retreated endoscopically: one with repeat laser incision alone and the other with balloon dilation with laser incision, for an overall success rate of 100%. The first patient had recurrent hematuria and an increase in size of a previously treated diverticulum 4 years after treatment. The infundibulum was scarred and narrow, but responded well to balloon dilation, laser incision and double stenting. The second patient underwent endoscopic intervention, but a wire could not be passed into the diverticulum during the initial operation and a failed attempt at laser incision of the infundibulum. The patient was rescheduled for a planned laparoscopic ablation; however, during the cystoscopy and retrograde pyelogram with stent placement at the start of surgery, the infundibulum accommodated the wire and ultimately the endoscopic approach was utilized.
Table 2 Indications for surgical intervention (including two re-operations). Indications
Number of patients (%)
Pain/increasing size UTI Hematuria Stones
8/15 3/15 3/15 1/15
(55%) (20%) (20%) (5%)
Discussion Pediatric calyceal diverticulum is a relatively rare entity, and the present cohort of patients and subsequent surgical management is the largest, to date, in the pediatric literature. In the present study, the techniques and experience utilizing ureteroscopy and laparoscopy to treat pediatric calyceal diverticulum have been presented. The experience reflects the interventions that are predicated for best practice, and an incorporation of techniques routinely applied for adult calyceal diverticulum management. Diagnosis of calyceal diverticulum is first suspected when a hypoechoic defect is seen within the kidney on a renal and bladder ultrasound, particularly when stones are present or there is an increase in size of the defect on subsequent studies. Diagnosis of calyceal diverticulum should be confirmed or ruled out with a contrast study. It is preferable to use MRU, due to the inherent necessity of significant radiation exposure in a CTU, particularly with the concerns about the impact of radiation upon the pediatric population. Alternatively, if a contrast study cannot be performed, a retrograde pyelogram in the operating room can confirm the presence of a communication with the collecting system. It can also provide a roadmap in the operating room by identifying the location of the infundibulum. Review of the adult literature provides comparison amongst the different treatment modalities for calyceal diverticula. Bas et al. found no significant difference in overall success rate for PCNL and URS (83% vs 76%, P Z 0.539), defined by symptom- and stone-free rates [6]. They did note a significant increase in major complications in the PCNL group due to its more invasive nature, and also noted that PCNL was able to address a larger overall stone burden. Auge et al. also compared PCNL and URS, finding PCNL superior at clearing increased stone burdens e but
Pediatric calyceal diverticulum treatment Table 3
172.e4
Summary of perioperative parameters: utilized approaches included endoscopy and laparoscopy.
Number of patients Location Endophytic Upper pole Mid pole Lower pole Exophytic Upper pole Mid pole Lower pole Size, median cm (range) Laterality, left, N Median decrease in size, cm (range) Complete resolution, N (%) No change, N (%) Improved, N (%) Median OR time, minutes (range) Median length of stay, days (range) Failure of initial therapy, N Stent duration, median days (range) Complications
Endoscopic
Laparoscopic
9/13 (73%)
4/13 (27%)
7 1 1
0 0 1
0 0 0 2.3 (1.3e3.5) 7/9 1.0 (0e2) 3/9 (33%) 3/9 (33%) 3/9 (33%) 69 (13e97) 0.25 (0.2e1.2) 2/9 45 (29e90) Repeat procedure 2 (Clavien III b) Perinephric hematoma 1 (Clavien I)
2 1 0 5.8 (2e10) 2/4 3.0 (2.4e7.2) 3/4 (75%) 0 (0%) 1/4 (25%) 172 (107e197) 2 (1.9e4) 0/4 41 (15e120) Deep vein thrombosis 1 (Clavien II)
with a higher complication rate [16]. The authors suggest that the percutaneous approach is ideal for posterior lesions and those with large stone burdens, at least compared to URS. Overall success rates of the PCNL approach range from 54 to 100% in the published literature [17]. Overall success rates for entry into and ablation of diverticulum via ureteroscopy range from 76 to 100% [7,10,16,17]. Finally, the laparoscopic approach results in overall success rates ranging from 66 to 100%, albeit using the most-invasive approach compared to URS or PCNL [13,17,18]. Casale et al. presented experience with laparoscopic diverticulectomy in three pediatric patients. They noted a 100% success rate with no complications [14]. All diverticula were Type 2 and were identified by retrograde pyelogram at the start of the procedure. All lesions were on the anteromedial portion of the kidney and were approached transperitoneally. The authors were able to identify and suture ligate the infundibulum in all patients. Urethral, ureteral, and perinephric drains were all removed on postoperative day 1. Estrada el al. operated on 10/23 (43%) patients who were identified as having calyceal diverticula at their institution from 1983 to 2006 [5]. Their initial procedure of choice was percutaneous ablation, but over the course of the inclusion period this had evolved to laparoscopic marsupialization. At a mean follow-up of 3.1 years there were no complications and a 100% success rate. The percutaneous approach was accomplished with direct access into the diverticulum, dilation of the tract into the renal pelvis, and obliteration of the cavity with electrocautery. The infundibulum of the tract was cauterized as well. Laparoscopically, the diverticulum was marsupialized, fulgurated, and filled with perinephric fat. A perinephric drain was left in place for 1e2 days.
The present study demonstrated an overall success rate of 100%, with two patients requiring repeat intervention for initial failure. This study is the first to report success with the ureteroscopic approach for treatment of calyceal diverticulum in the pediatric population. Endophytic lesions were found, which were unlikely to be visible on the surface of the kidney, located at the mid to upper pole and ideal for endoscopic ablation. One endophytic, lower-pole lesion was approached laparoscopically as it was believed that the anatomical location would limit scope deflection and, hence, the ability to successfully treat the diverticulum. Balloon dilation of the infundibular tract was performed when the tract was large enough to accommodate passage of the balloon over an appropriate guide wire. When the tract was too small to pass the balloon, the holmium laser was used to incise the tract to allow for scope passage. The tract was then further dilated with the balloon, if not sufficiently done so with the laser. The cavity was then ablated with electrocautery or the holmium laser. Postoperatively, it was preferred to place two double J stents across the infundibulum directly into the cavity in order to prevent collapse of the dilated tract, although double stenting was not feasible in all patients. Although complete radiographic resolution occurred in 3/9 (33%) endoscopically treated patients, symptoms resolved in all e two were after repeat endoscopic ablation. Of note: 3/9 (33%) endoscopically treated patients had no discernable change in radiographic appearance. The one patient in the cohort with a stone localized within a diverticulum was successfully treated via the ureteroscopic approach. As expected, the laparoscopic approach had longer median operative times (172 vs 69 min) and median length of stay (2 vs 0.25 days).
172.e5 Technical considerations for the ureteroscopic approach included the following: stent size was determined based upon the safest allowable size that could be accommodated by the ureter and infundibulum. If the ureter would not accommodate scope passage, passive ureteral dilation with internal stenting and a staged approach was preferentially performed, as opposed to active coaxial ureteral dilation. A double-stenting technique was preferred, when possible, to maximally dilate the infundibulum. It was felt that the presence of the ureteral stent into the diverticulum facilitated healing of the tract to maintain patency. When utilizing the laparoscopic approach, suturing the infundibular tract is recommended to prevent a prolonged urinary leak after diverticulectomy. Alternatively, patients can be counseled that internal ureteral stenting and Foley catheter utilization can aid repair, albeit with prolonged catheter placement. The laparoscopic approach was performed for exophytic (3/4 patients) or lower pole (1/4) lesions. It is believed that this is the first description of pediatric single port calyceal diverticulectomy (2/4 patients). It is preferable to leave a perinephric drain, an internal double J stent, and a Foley catheter in situ after the procedure. Length of time maintaining a ureteral stent and urethral catheterization are dependent upon the output recorded in the perinephric drain. One patient required a Foley catheter for 1 week due to persistent perinephric drain output suggesting a persistent urine leak; the leak resolved spontaneously. Of note: the infundibulum was not sutured on this patient and this resulted in a change in future postoperative practice. Radiographic improvement was more pronounced in the laparoscopic group compared to the URS group, although complete symptom resolution was noted in all patients. Although previous reports have identified a strong concordance of VUR and pediatric diverticulum [19], and as the management of VUR has evolved in the field of pediatric urology, VCUG studies are not routinely performed at the present institution. In the present study, 2/13 (15%) patients diagnosed with a UTI underwent VCUG in addition to US for UTI workup. These patients were young (
