URETEROSCOPIC MANAGEMENT OF INTRARENAL CALCULI

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Vol. 159. 1139-1143, April 1998 Printed in U . S A

THE JOURNAL OF UROUJGY

Copyright 0 1998 by AMERICAN UROLOCICAL ASSOCIATION, INC.

URETEROSCOPIC MANAGEMENT OF INTRARENAL CALCULI MICHAEL D. FABRIZIO, ASHISH BEHARI AND DEMETRIUS H. BAGLEY* From the Department of Urology, JeffersonMedical College, Thomas Jefferson University, Philaaklphia, Pennsylvania

ABSTRACT

Purpose: To determine its potential role in stone therapy, we evaluated our experience with the ureteroscopic removal of intrarenal calculi in 100 patients. We review the indications, techniques, stone-free and overall success rates, and complications. Materials and Methods: From July 1994 to December 1996 ureteroscopic stone removal was attempted in 100 patients a mean of 52 years old who had renal calculi. Indications for treatment included concurrent ureteral stones in 56 cases, and failed extracorporeal shock wave lithotripsy, medical or percutaneous management as well as obesity and anatomical anomalies. There were 2 or more calculi in the affected kidney in 68 patients and stones greater than 6 mm. in 67. Treatment of intrarenal calculi was performed with flexible ureteroscopes, a laser or electrohydraulic lithotriptor and endoscopic graspers. The number and size of calculi were noted in each patient. Stone-free and overall success rates defined as 1residual fragment less than 3 mm. were noted at 1and 3-month followup visits. Results: The overall success rate was 89%. Ureteroscopic treatment of intrarenal calculi resulted in a 77% stone-free rate. Of the 23 patients with residual calculi 12 (52%) had a single residual fragment less than 3 mm. The targeted stone was removed or fkagmented in 98 patients (98%) and no ureteral calculi remained postoperatively. As expected, the number and size of the original stones inversely correlated with the success rate. There were no intraoperative complications, and only 3 urinary tract infections and 3 fevers were noted postoperatively. Conclusions: The use of smaller diameter ureteroscopes, better working instruments and more effective lithotriptors allow calculi in all parts of the collecting system to be engaged and treated. Success rates throughout the whole collecting system are comparable to if not better than those of extracorporeal shock wave lithotripsy and percutaneous approaches. KEYWORDS: kidney, lithotripsy, calculi The management of renal and ureteral calculi has changed dramatically in the last 25 years. Therapeutic options available to the urologist have expanded from open surgical intervention to far less invasive procedures today. The development of small fiberoptic, flexible ureteroscopes added another modality to treat ureteral and renal calculi. In fact, the early use of flexible ureteroscopy dates back to the 1960s.' Although described in the early 19508,percutaneous renal surgery eventually found a role in the treatment of renal and ureteral calculi.24 In addition, by the mid 1980s the innovative study of Chaussy et a15 had led to the development of extracorporeal shock wave lithotripsy (ESWLt) as standard treatment of most upper tract ~alculi.6.~ Some of the most important advances in the field of urology have arguably been the gradual decrease in the size of the ureteroscope and the development of effective lithotriptors. These advances have enabled the urologist to treat complex ureteral and renal calculi successfully. Electrohydraulic and laser lithotriptors have been shown to be effective in the ureter and kidney.'-13 In fact, several studies have documented high stone-free success rates throughout the ureter using these sophisticated instruments. Our series demonstrates the high success rates that can be achieved using ureteroscopy to treat intrarenal calculi.

MATERIALS AND METHODS

We retrospectively reviewed the records of patients who underwent ureteroscopic stone removal for renal calculi from July 1994 through December 1996.Results were determined aRer a single ureteroscopic procedure in each patient and only those followed in this institution were included in the study. We evaluated 59 men and 41 women 8 to 77 years old (mean age 52) (table 1).The body mass index was used to determine obesity with a value greater than 30 indicating obesity.l4 Preoperatively radiographic evaluation included abdominal plain x-rays, excretory urograms and renalbladder ultrasound. Special consideration was given to the characteristics of failed ureteroscopic procedures. Complications were determined from the intraoperative and postoperative records. The indications for ureteroscopic stone extraction were subdivided into certain categories with some overlap among the categories, including failed ESWL,ureteroscopy, percutaneous extraction or medical therapy, obesity (defined as

Accepted for publication October 17,1997. * Requests for reprints: De artment of Urology, Jefferson Medical College, 11th Floor College %I&., 1025 Walnut St., Philadelphia, Pennsylvania 19107. t Dornier Medical Systems, Marietta, Georgia. 1139

TABLE1. Patient characteristics Av. age (p.) Mean/-. wt. (lb.) No. pta. stone-fiee: At 1 mo. At 3 mo8. No. pts. not stone-Less than 3 mm. stones M& days hospital stay Mean mins. operative time

52 2w400 77 64 13 23 12 0.5 95

URETEROSCOPIC MANAGEMENT OF INTRARENAL CALCULI

1140

mass index greater than 3014), concurrent ureteral stone and anatomical variance (table 2). The most common indication for treatment was coexisting ureteral and renal calculi in 56 patients. A total of 24 patients who presented primarily with no previous treatment had simultaneous ureteral and rend calculi, while 36 presented as a result of E S n failure, including32 with ureteral fragments (table 2). Three patients required an immediate stone-free result secondary to their professions (for example pilot). Intervention was performed using general anesthesia (mask, laryngeal mask or endotracheal tube) in 79% of the cases, monitored anesthesia care (intravenous sedation) in 14% and spinal anesthesia in 7%. Semirigid and flexible ureteroSCOPeS were Used in a retrograde fashion. A 6.W semirigid ureteroscope with 3.4 and 2.3F working channels was used for distal and WCasiOnallY mid stones. An m a y of actively deflectable, flexible uretemscopes were availab1e for proximal ureteral and renal calculi. Ureteroscope size ranged from 9.8 to 7.5Ft facilitating easier Passage into the ureter*The ureteroscOpe was passed over a 0.038-inch guide Wire after a second Safety wire W a s lumen inserted into the ureter, with a l°F catheter. The double lumen catheter facilitated replacement Of a guide wire each time the ureteroscOpe was reinserted into the collecting system. instruments permitted retrieval Of stone fragments. In the distal ureter wire baskets were used with the 2 channel semirigid UreterOSCOpe. The dual channels allowed passage of an endoscopic lithotriptor when necesWhen a ureteroscope* a ible instrument as the 2*5Fwire pronged grasper was preferred* Fragments that were not successfully removed intact were with laser Or an electrohydraulic lithotriptor. The holmium:YAG laser is the most effective lithotrite a ~ a i l a b l e . ~ ~ The * ' ~ *2,100 ' ~ nm. wavelength laser and fragments stones Of all quartz are 2oo to 19000 p' in diameter' In the ureter the setting was tYPically limited to less than and in the capacious renal up to L4 were applied. most Common fragmentation technique has been described as direct fragmentation inwhich the fiber is applied along cleavage planes on the stone surface.17 The recent Of the 2oo p' fiber appmximately 120 degrees Of active with the scope' facilitatingaccess into the lower Lower calculi were treated by grasping the with a 2'5F wire pronged Or irrigating the fragments into a more accessible location, where the h0lmium:YAG laser was used to fragment them further. Occasionally the 1.6 or 1.9F electrohydraulic lithotripsy probe was used to fragment lower calculi that were the quartz laser calculi were retrieved Or fragmented to an acceptable size (less than 2 mm.). At completion of the procedure the coueding system was inspectea for residual calculi* A ureteral was left in in all patients with pigtail Or without a string for subsequent removal.

'

J*

J'

TMLE 2. Indications for treatment Indication coexisting ureteral caleuli. Failed ESWL Rimary presentation Obesity (body mass index greater than 30): Failed ESWL Failed E S m With ureteral fragments Anatomical m o d y Failed chemolyaia Failed percutaneous extraction Frequently more than 1 indication per patient.

Postoperative followup consisted of an abdominal plain x-ray within a month of the procedure to evaluate the kidneys, ureter and bladder. Renal ultrasound was commonly performed as part of the postoperative evaluation to detect calculi as well as rule out obstruction. Excretory urography was occasionally performed at followup. Stone-free results were reported at the 1 and 3-month postoperative visits. Overall success rates were determined by including in the results patients with a single residual, clinically insignificant fragment less than 3 mm. Those with larger residual calculi were treated further according to clinical status. RESULTS

Average patient height and weight were 67 inches (170 cm.) and 204 pounds (92.7 kg.), respectively (table 1).Average mass index was 32 with obesity defined as a body index greater than 30.l4 A total of 56 patients (56%) had combined ureteral and renal calculi, while the remaining 44 had intrarenal calculi (44%).Of the 63 patients with associated lower pole calculi 20 had a single lower pole calculus (table 3). Patients were grouped into 4 categories according to the size and number of stones (table 4). There were or more calculi in the affected kidney in 68 patients and stones greater than 6 m.in 67 (table 4). Ofthe 100 patients in our series 10 (10%)had anatomical anomalies, including a solitary kidney in 3, ureteropelvic junction obstruction in 2, and crossed-fused renal ectopia, a caliceal diverticulum, horseshoe kidney, pelvic kidney and history of emtrophy in 1 each. The overall success rate was 89%.Ureteroscopic treatment of intrarenal calculi resulted in a 77% (77 patients) stone-free success rate. Of the 23 patients (23%) who were not stonefree at the end of the 3-month period 12 (52%) had a single insidcant fragment less than -., which is frequently defined as success in the ESWL literature.6,7,1~ At month 64 patients (64%)were rendered stone-free and the remaining 13 (13%)were stone-free by 3 months (table 1). The targeted stone was removed or fragmented in 98 cases (98%). In 2 patients (2%)the targeted calculi could not be treated. One patient who had undergone a left lower pole percutaneous procedure had a stenotic lower pole infimdibulum and 1 had an inaccessible It is interesting to note the total number of calculi at the time of treatment (table 4). While 32 patients (32%) had a single stone at presentation, 31 (31%)had 4 or more renal calculi at treatment (table 4). The size of the largest stone ranged from 1to 5 mm. in 33 patients, 6 to 10 in 42,11 to 15 in 14 and greater than 15 in ll. There were concurrent ureteral and renal calculi in 56 patients (56%) and rend calculi only in 44 (44%). We evaluated the characteristics of the patients with residual calculi (figs. 1and 2). Of the 23 patients with residual fragments 12 (52%) had a single remaining fragment less than 3 mm. No residual ureteral fragments were noted and a majority of the residual renal fragments were found in the lower pole in 18 cases. Figure1showsthe numbr ofresidual calculi in relation to the original number of renal calculi. As expected, increased stone burden led to a higher percentage of patients with residual fragments. Figure 2 shows residual

No. Pta. 56 32 24 40 20 36 32 10 3 1

TABLE3. Location ofcalculi Location Ureterallrenal stones: Steinstrasse Renal other than lower pole Lower pole stones: + Ureteral + Other calk + Other calix/ureter Lower pole only

No. Pts. 56 5

37 63 13 13 17 20

URETEROSCOPIC MANAGEMENT OF INTRARENAL CALCULI TABLE4. Number and location

of

calculi No.Pta. ~

No.original calculi: 1 2 3 4 or More Largest size of original calculus (nun.): 1-5 6-10 11-15 16-20 20 or Greater

32 23 14 31 33 42 14 5 6

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using anesthesia work sheets. Mean operative time was 95 minutes (range 20 to 315) and mean hospital stay was 0.5 iays (range 0 to 6).There were no intraoperative complications and postoperative complications were rare. In the immediate postoperative period 3 patients (3%) had fever, defined as greater than 38.5C,while in 3 (3%) a documented urinary tract infection was treated with appropriate antimicrobials. No mortality or long-term complications have been obsemed. Stone composition was calcium oxalate monohydrate in 66% of the cases, mixed in 1396,uric acid in 12%, calcium phosphate in 7% and cystine in 2%. DISCUSSION

ONE

TWO THREE FOUR # O F STONES

FIG.1. Residual calculi in relation to original number of renal calculi. As number of stones increased, percentage of patients with residual fragments increased.

EACH ORIGINAL

I-5mm 6-IOmm

11-

16-

>20mm

15mm 20mm

FIG.2. Residual calculi in relation to original renal c d , d size. h onginal stone size increased, percentage of patients m t h resldual fragments increased.

calculi in relation to the size of the largest original renal calculi. Again, larger size was associated with a greater chance of residual stones postoperatively. When the ureteroscope could not be passed in 18 patients (18%), the ureteral orifice was dilated, usually with a graduated 6 to 12F dilator (table 5). One patient required balloon dilation of the ureteropelvic junction. Notably 37 patients presented with previously placed ureteral stents (table 5). Although this stent served to dilate the ureter, it had no effect on calculi. A catheter was placed in all patients postoperatively and in the majority a dangler string remained for easy removal. Operative time was determined as accurately as possible TABLE5 . Ureteral dilation with ureteroscopy Type

No.Pta.

Graduated 6-12F dilators Balloon dilation Ureteropelvic junction balloon dilation F'reop. stent

13 5

1 37

There have been dramatic changes in the management of ureteral and renal calculi. The initial report of Drach et al in 1986 indicated an overall 77.4% stone-free success rate at 3 months for upper ureteral and renal calculi? When 4 or more stones were present in that study, the success rate decreased dramatically to 29%. Similarly Lingeman et al reviewed their experience with ESWL and found that 72% of cases were stone-free at 3 months and 24% had clinically insigniscant fragments less than 5 mm.7In a more recent study comparing ESWL results Cass noted overall 70% stone-free success for all renal calculi but 55% for multiple stones.'' These residual fragments after ESWL may not only progress, but also lead to complications such as steinstrasse that oRen require further endoscopic management.20*21In these series the most common causes of a failed procedure were failure to fragment or localize calculi, or detect upper tract obstruction. Thomas and Cass noted that obesity oRen limits urologist ability to place the stone in the F2 focal point, thus, inhibiting fragmentation.22When multiple calculi are present in the ureter and kidney, re-treatment with ESWL is oRen necessary and success rates decrease significantly. Furthermore, Parr et al questioned the role of ESWL for confined and impacted Calculi.23 The stone-free success rate of ESWL for lower pole stones is limited as well. Stone-free success rates range from 41 to 79% in the most successful ~ e r i e s . 2 ~Sampaio "~ and Aragao found that the clearance of fragments in the lower pole after ESWL may be directly related to the angle of the infundibulum.27Although highly successful for lower pole calculi, percutaneous nephrostolithotomy is associated with a long hospital stay and numerous complications, including transElashry et al recently advocated endoscopic management of these lower pole stones.13 In an impressive series of percutaneous removal of renal calculi Segura et al reported 98% overall success in removing the targeted stone.3 However, the average hospital stay was 5.2 days and 30 patients required transfusion. More recently, Lingeman et al noted an average 4.7-day hospitalization?6 Although the percutaneous approach is extremely useful for staghorn calculi, the ureteroscopic approach effectively treats most renal calculi and limits morbidity, hospital stay and cost. With the advent of flexible ureteroscopic techniques the success rates of stone removal have increased throughout the collecting system. In the mid to late 1980s it was possible to examine the whole collecting system using the flexible ureteroscope in 85 to 96% of patients.10*29This diagnostic ability lead to therapeutic applications. Using the rigid ureteroscope the success rates of ureteroscopic treatment of distal ureteral stones were consistently in the 90% or greater range.s.25.30 As the flexible ureteroscope evolved and more effective endoscopic lithotrites were developed, the success rates of treatin mid and proximal ureteral calculi approached 1oO%.'f 12*15*25*31.32 This technique is not only successful, In addition, patients with simulbut also taneous ureteral and renal calculi may be prone to failed of ESWL monotherapy. Others have reported the advan-

1142

URETEROSCOPIC MANAGEMENT OF INTRARENAL CALCULI

combining rigid and flexible ureteroscopy with ESWL to treat common and probably least traumatic tool used was the 10 or ureteral and renal calculi with high stone-free success 12F graduated dilator and balloon dilation was rarely needed. With increased complexity operative time may be rates.3537 Limited studies have indicated the success rates of uret- expected to increase, since we now treat larger, multiple eroscopic treatment of renal calculi. Bagley s~ccessfllu~ re- stones in the kidney. However, the average operative time of '~~ to moved 87% of intrarenal calculi using 8.5 to 9.8F flexible 95 minutes is comparable to that of other s e r i e ~ . ' ~Due uretemscopes? Grasso treated 26 patients in a retrograde the ability to treat multiple stones in the ureter and kidney fashion with the ho1mium:YAG laser, of whom 88.5% re- at a single setting ureteroscopy has been shown to be efficacious and c o ~ t - e f f e c t i v e . ~ ~ * ~ ~ quired a single treatment." There are several advantages to considering flexible ureteroscopy as first line treatment for renal calculi, especially CONCLUSIONS when there are concurrent ureteral stones. Success rates are "his series demonstrates the value of ureteroscopy for comparable to those in the literature for ESWL. When considering treatment of simultaneous ureteral stones, the SUC- managing upper tract calculi. Flexible ureteroscopy offers cess rates approach 100% throughout the ureter. Also, al- the advantage of treating ureteral and renal calculi at a though more invasive than ESWL, ureteroscopy provides an single setting. The use of smaller diameter ureteroscopes, attempt to remove the targeted stone completely at a single better working instruments and more effective lithotriptors setting. In addition, ureteroscopy is far less invasive than allow calculi in all parts of the collecting system to be enpercutaneous nephrostolithotomy and it is associated with gaged and treated. Using these instruments we treated the targeted stone in 98% of our patients. Ureteroscopy may be decreased morbidity, cost and hospital stay. We achieved 89% overall success in our series. Of our 100 considered effective first line therapy for upper tract calculi patients 77% were rendered stone-free aRer a single session with limited morbidity even in high risk, obese patients. and the remaining 12% had a single asymptomatic fragment Success rates throughout the whole collecting system are less than 3 mm. These results are comparable to those of the comparable to if not better than those of ESWL and percubest ESWL series for intrarenal calculi. Importantly in 56 taneous approaches. patients in our series concurrent ureteral and renal calculi were treated at a single setting with no residual ureteral REFERENCES fragments. Flexible ureteroscopy provided the ability to ad1. Marshall, V. F.: Fiberoptics in urology. J. Urol., 91: 110, 1964. dress renal and ureteral locations simultaneously, and the 2. Segura, J. W., Patterson, D. E., LeRoy, A. J., May, G. R. and targeted stone was removed or fragmented in 98% of cases. Smith, L. H.: Percutaneous lithotripsy. J. Urol., 130 1051, Perhaps more important is that 68% of the patients had 2 or 1983. more stones at presentation and 31%had 4 or more. It would 3. Segura, J. W., Patterson, D. E., LeRoy, A. J., Williams,H. J., Jr., be difficult to address this number of stones successfully at a Barrett, D. M., Benson, R. C., Jr., May, G. R. and Bender, single session using only ESWL. A majority of patients were C. E.: Percutaneous removal of kidney stones: review of 1,000 noted to have lower pole calculi a t presentation. Although it cases. J. Urol., 134: 1077,1985. 4. Reddy, P. K., Hulbert, J. C., Lange, P. H., Clayman, R. V., is debatable whether asymptomatic lower pole calculi require Marcuzzi, A., LaPointe, S., Miller, R. P., Hunter, D. W., treatment, in most of our patients calculi were present a t Castaneda-Zuniga, W. R. and Amplatz, K: Percutaneous reother locations throughout the collecting system. We treated moval of renal and ureteral calculi experience with 400 cases. these lower pole calculi with little change in operative time J. Urol., 134:662,1985. and limited morbidity. As expected, the number of stones 5. Chaussy, C., Schmiedt, E., Jocham, D., Brendel, W., Forssmann, inversely correlated with success rates. B. and Walther, V.: First clinical experience with extracorpoThe development of smaller, more effectiveworking instru- . really induced destruction of kidney stones by shock waves. ments and lithotriptors has enhanced our ability to perform J. Urol., 127: 417, 1982. ureteroscopy successhlly. Small working instruments allow 6. Drach, G. W., Dretler, S., Fair, W., Finlayson, B., Gillenwater, J., deflection of the ureteroscope into once inaccessible regions Griflith, D., Lingeman, J . and Newman, D.: Report of the United States cooperative study of extracorporeal shock wave in the collecting system. The 1.9F electrohydraulic litholithotripsy. J. Urol., 136 1127, 1986. tripsy probe permits easy deflection of the ureteroscope into 7. Lingeman, J. E., Newman, D., Mertz, J. H. 0, Mosbaugh, P. G., the lower pole,13 while the ho1mium:YAG laser has proved to Steele, R. E., Kahnoski, R. J., Coury, T. A. and Woods, J. R.: be an effective lithotrite for all forms of calculi.12*15,16*3s Extracorporeal shock wave lithotripsy: the Methodist Hospital We were unable to engage the targeted stone in 2 patients. of Indiana experience. J. Urol., 135. 1134,1986. In 1patient a previous leR lower pole percutaneous nephros8. Higashihara, E., Hone, S., Takeuchi, T., Kameyama, S., tomy tube presumably led to i n h d i b u l a r stenosis. 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pyeloacopy: diagnosis and treatment in Ihe u p p r ~ r i ~ r y tract. J. Urol.. 1s8: 280. 1987. 30. Seeger, A. R.,Rittenberg. M.H.and Rqley. D. H.:Urctcropyeloacopic removal of ureteral calculi. J . Urol.. 138: 1180. 1988. 31. Crasao, M.,Loisides. P., Benghler, M. and Bagley, D. H.:The c u e for. primary endoacopic management of upper urinary tract calculi: I. A critical review of 121 extracorporeal shockwave lithotripsy failures. Urology, lb: 363. 1995. 32. Boline. C. B. and Belis, J. A.: Outpntient fragmentation of ureteral calculi with mini-ureterowopes and laser lithotripy. J . Endourol., 8: 341, 1994. 33. Crasao. M.,Beaghler, M.and Lainides. P.:The CW for primary endoscopic management of upper urinary trad calculi: 11. Cost and outcome assessment of 112 primary ureteral calculi. Umlogy, 372, 1995. 34. Kapoor, D. A.. Leech, J . E., Yap, W. T., Rose, J . F..Knbler, R.m d Mowad. J . J.: Cost and eficacy of extracorporeal shock wave lithotripsy versus ureteroscopy in the treatment of lower ureteral calculi. J. Urol., 148: 1095. 1992. 35. Jarowenka, M.V., Belis, J . A. and Rohner. T. J.. Jr.: Management of simultaneous renal and ureteral calculi: combined extracorporeal shock wave lithotripsy and ureteroecapy under a single anesthetic. J . Urol., 1 4 2 1186. 1989. 36. Dretler, S. P.: Ureteroscopic fragmentation followed by extracorporeal shock wave lithotripsy: a treatment alternative for belected large or staghorn calculi. J. Urol., 161: 842, 1994. 37. Marini, F., Martino, F.. Alfano. V. and Valente, R.: Combined therapy of staghorn calculi with ureteroneph-py (URS) and extracorporeal shock wave lithotripsy (ESWL).Arch. Esp. Urol., 4 2 945, 1989. 38. Denstedt, J. D.. Razvi, H. A.. Sales, J. L. and Eberwein, P.: Preliminary experience with ho1mium:YAC laser lithotripsy. J. Endourol.. 9: 255, 1995. 39. Hofmann, R. and Stoller. M. L.: Endoscopic and open stone surgery in morbidly obew patients. -1. Urol., 118: 1108. 1992. 40. Abdel-Razzak. 0. M. and Bagley, D. H.: Clinical experienoc with flexible ureteropyelompy. J. Urol., 118: 1788. 1992.

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