Treatment of Staghorn Calculi by Fiberoptic Transurethral Nephrolithotripsy

0022-534 7 /S0/1441-0017$02.00/0 Vol. 144, July

THE JOURNAL OF UROLOGY

Printed in U.S.A.

Copyright© 1990 by AMERICAN UROLOGICAL ASSOCIATION, INC.

TREATMENT OF STAGHORN CALCULI BY FIBEROPTIC TRANSURETHRAL NEPHROLITHOTRIPSY YOSHIO ASO, NOBUTAKA OHTA, MASARU NAKANO, YOSHIHISA OHTAWARA, ATSUSHI TAJIMA AND KAZUKI KAW ABE From the Departments of Urology, Faculty of Medicine, The University of Tokyo, Hongo, Tokyo, and Hamamatsu University School of Medicine, Hamamatsu, Japan

ABSTRACT

We treated 34 patients with staghorn calculi by fiberoptic transurethral nephrolithotripsy with a flexible nephroureteroscope and an electrohydraulic lithotriptor. Of the 34 patients 30 (88.2%) were treated successfully. There were 17 patients each with complete and partial staghorn calculi. There was no difference in the success ratio and the rate of residual fragments between the 2 groups. However, post-procedural fever, sepsis and extrapelvic extravasation were observed more frequently in patients with complete than with partial staghorn calculi. Countermeasures to avoid complications must be developed in the future. However, we believe that fiberoptic transurethral nephrolithotripsy is a safe and effective treatment for staghorn calculi. This procedure also should be recommended, as well as the combination of percutaneous nephrolithotomy and extracorporeal shock wave lithotripsy. (J. Ural., 144: 17-19, 1990) The treatment of staghorn calculi still is a problem in urological practice even in the age of extracorporeal shock wave lithotripsy (ESWL*). 1 • 2 We have treated upper urinary tract stones with an electrohydraulic lithotriptor combined with an Olympus fiberoptic nephroureteroscope. 3 •4 Recently, we encountered cases of staghorn calculi that were treated successfully with our method despite failure of ESWL. We describe the method of transurethral fiberoptic pulverization and removal of staghorn calculi. MATERIALS AND METHODS

From September 1986 to March 1989, 34 patients were treated by fiberoptic transurethral nephrolithotripsy in conjunction with electrohydraulic lithotripsy of staghorn calculi. The complete staghorn calculi group consisted of 5 men and 12 women 42 to 66 years old (mean age 55.5 ± 8.0 years), and the partial staghorn calculi group included 11 men and 6 women 41 to 84 years old (mean age 56.5 ± 10.2 years). The mean age of the 34 patients over-all was 56.0 ± 9 years. The stone size classified according to the longest dimension is shown in table 1. One patient in each group had a staghorn calculus that was not properly disintegrated previously by ESWL. We used an operative flexible nephroureteroscope and an electrohydraulic lithotriptor for stone removal. Four types of flexible nephroureteroscopes were used in our study. The specifications of these instruments are shown in table 2. The XURF-2.0 device measures 4.5 mm. in diameter at the working portion with a working channel 2.0 mm. in diameter. It was manufactured during the earliest period of development of an operative fiberscope for the upper urinary tract. The URF device, with a 4.1 mm. in diameter working portion and a 1. 7 mm. in diameter working channel currently is used mainly for the upper and middle calices in which the fiberoptic nephroureteroscope is manipulated easily or when a 4.5F electrohydraulic lithotriptor is preferred for hard calculi. The URF -P instrument is the thinnest device with a 3.5 mm. working portion and a 1.2 mm. working channel. This instrument is used mainly for the lower calix, where manipulation of the fiberoptic device is more difficult compared to that in the upper and middle calices, or for a friable stone that can be Accepted for publication January 10, 1990. Read at annual meeting of American Urological Association, Dallas, Texas, May 7-11, 1989. * Dornier Medical Systems, Inc., Marietta, Georgia.

disintegrated by a 3.5F electrohydraulic lithotriptor. The specifications of the URF -PWX device are the same as those of the URF -P instrument except for a wider angle of field due to the objective fish eye lenso To insert the operative nephroureteroscope the ureter is dilated with a balloon dilator after a guide wire is placed in the ureter. Then, a polytetrafluoroethylene (Teflon) catheter consisting of a thin outer sheath and stylet is slipped over a guide wire. The stylet then is replaced by the nephroureteroscope. The generator of the electrohydraulic shock wave was the EL21.

t

Staghorn calculi were disintegrated by electrohydraulic lithotripsy under direct vision, when calculi and mucosa were visualized clearly after proper irrigation. RESULTS

With our method insertion of the fiberoptic nephroureteroscope into the ureter was not difficult and it was successful in all 34 patients. In no patient with a staghorn stone was insertion impossible. The procedure was considered successful when the stone was disintegrated into particles smaller than 5 mm. in diameter at the end of a session. Complete and partial staghorn calculi were treated successfully in 15 of the 17 patients (88.2%) in each group. Total disappearance of a calculi was observed in 9 of 17 patients (5209%) with complete and 8 of 17 (47.1 %) with partial staghorn stones (table 3). One to 4 sessions of fiberoptic transurethral nephrolithotripsy were required to disintegrate staghorn calculi depending on stone size and hardness. The 17 patients with complete staghorn calculi underwent a total of 29 sessions: 9 required 1, 5 required 2, 2 required 3 and 1 required 4 sessions. The average number of sessions was 1.7. On the other hand, a total of 23 sessions was done in the 17 patients with partial staghorn calculi: 12 required 1, 4 required 2 and 1 required 3 sessions. The average number of sessions was 1.4. The interval required for 1 session ranged from 40 to 180 minutes (average 98.9 minutes) for complete staghorn calculi, while that for partial staghorn calculi was 40 to 200 minutes (average 90.1 minutes). The numbers of electrohydraulic lithotripsy probes consumed

t Walz Elektronik GmbH., Waldorfea Str. 40, D-7271, Rohrdorf, West Germany.

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ASO AND ASSOCIATES TABLE 1.

Size of staghorn calculi described in longest diameter Staghorn Calculi (No. pts.) Partial

Complete Diameter of stone (mm.): 49 50-59 60-69 70-79 80-89 90+ Partially fragmented by previous ESWL

0 5 2 3 4

5

5 4

1 1

1 1

0

1

lithotripsy because of the hardness. The patient with the uric acid stone was treated later with medication. Nephrolithotomy was performed in the patient with the calcium oxalate calculus. Complications are noted in table 5. Fever higher than 38C was observed in 11 of the 29 sessions (37.9%) for complete staghorn calculi. In 4 of the 29 sessions (13.8%) sepsis followed the procedure. Among the patients with partial staghorn calculi fever developed in 6 of the 23 sessions (26.1 %). Infectious stones were noted in 23 of the 34 patients. The urinary tract infection resolved after the procedure in all pa tients regardless of the presence of disintegrated stone particles. DISCUSSION

TABLE 2.

Specifications of 4 types of fiberoptic nephroureteroscope XURF-2.0 (Olympus)

URF (Olympus)

URF-P (Olympus)

URF-PWX (Olympus)

Angle of field (degrees) 75 75 75 100 4.5 (13.5F) 4.1 (12.3F) 3.5 (10.5F) 3.5 (10.5F) Diameter (mm.) Angulation (degrees): Up 160 160 160 160 60 100 100 Down 100 2.0 (6.0F) 1. 7 (5.lF) 1.2 (3.6F) 1.2 (3.6F) Diameter of working channel (mm.) Working length 700 700 700 700

TABLE 3.

Results of fiberoptic transurethral nephrolithotripsy in 17 patients in each group Staghorn Calculi Complete

No. successfully fragmented(%) No. free of stones at followup (%) No. sessions (No. cases): 1 2 3 4

Partial 15 (88.2) 8 (47.1)

15 (88.2) 9 (52.9)

12

9 5 2

4

1

1 1. 7 3.4

Av. No. sessions for 1 case 1.4 3.5 Av. No. electrohydraulic lithotripsy probes for 1 session Mins. for 1 session (mean ± stand- 40-80 (98,9 ± 39.1) 40-200 (90.1 ± 35.1) ard deviation)

TABLE 4.

Composition of staghorn calculi Staghorn Calculi Complete

Partial

12 1 1 1

9

Calcium phosphate Calcium oxalate Uric acid Magnesium ammonium phosphate Unknown Totals

TABLE 5.

4 3 0 0

2

17

17

Complications of fiberoptic transurethral nephrolithotripsy Staghorn Calculi

Total No. sessions Complications: Fever (>38.0C) Sepsis Extravasation from renal pelvis Subcapsular hematoma Totals

Complete No.(%)

Partial No.(%)

29

23

11 (37.9) 4 (13.8) 1 (3.4) 1 (3.4) 17 (58.6)

6 (26.1) 0 (0.0) 0 (0.0) 0 (0.0) 6 (26.1)

during 1 session were 3.4 for complete and 3.5 for partial staghorn calculi. The composition of the stones is summarized in table 4. Calcium phosphate was noted most frequently in our series. Two partial staghorn calculi consisted of uric acid and calcium oxalate that could not be disintegrated by electrohydraulic

It has been stated that complete staghorn calculi are more difficult to treat by percutaneous nephrolithotripsy5 or ESWL6 compared to partial staghorn calculi. However, with fiberoptic transurethral nephrolithotripsy there was no difference in the rates of success and of residual fragments between the 2 groups. It seems that complete staghorn calculi could be treated by fiberoptic transurethral nephrolithotripsy with no more difficulty than partial staghorn calculi. However, post-procedural fever and sepsis were observed more frequently in the complete staghorn group. This finding might be due to more rapid and abundant infusion of the irrigation fluid, and excessive manipulation in the complete staghorn group. Presently, an open operation, percutaneous procedures,5 ESWL, 6 and ESWL combined with a percutaneous procedure7• 8 are accepted as the treatments of choice for staghorn calculi. The percutaneous procedure is relatively invasive, since it perforates the renal perenchyma and causes bleeding. In contrast, fiberoptic transurethral nephrolithotripsy causes minimal renal injury and secures passage of stone particles, since it is possible to observe the condition of the ureter during the procedure. Snyder and Smith reported that blood transfusion was required in 52.9% of the patients with staghorn calculi who underwent a percutaneous procedure. 9 Residual stone fragments also were noted in 10 of the 75 cases (13.3%). Combined ESWL and percutaneous nephrolithotripsy is a recent recommended therapy for staghorn stone. Schulze and associates reported that the rate of residual fragments was decreased to 15% by the combination therapy. 10 However, it should be noted that those rates were not attained at the time the patient was discharged from hospital but during followup. Post-procedural high fever and sepsis must be avoided. Normally, we begin antibiotics 2 days before the procedure in patients with infected urine. Fluid irrigation during fiberoptic transurethral nephrolithotripsy was limited to the minimum degree necessary to obtain a clear visual field. When a single J stent was obstructed with stone particles after fiberoptic transurethral nephrolithotripsy high fever always ensued. It was necessary to irrigate the renal pelvis frequently and evaluate the hydronephrotic condition of the kidney by ultrasonography after the procedure. In patients with a struvite stone a single J stent was obstructed easily with stone particles. Therefore, a Tower peripheral stent was placed in addition to a single J stent. The fluid absorption during fiberoptic transurethral nephrolithotripsy also should be minimized, although we could not measure the intrapelvic pressure, since a pressure sensor was not available at the tip of the fiberoptic nephroureteroscope. To avoid excessive fluid absorption, fluid leakage around the device was observed carefully. We assumed that no marked elevation of the intrapelvic pressure was present when we observed reasonable leakage around it. In cases of slight leakage of the fluid around the fiberoptic device or in those with a longer procedural time 20 to 40 mg. furosemide were administered prophylactically to prevent fluid accumulation. In regard to the size of the stone fragments particles smaller than 5 mm. in diameter usually were passed spontaneously in due time after the procedure. Therefore, when the stone was

TREATMENT OF STAGHORN CALCULI BY FIBEROPTIC TRANSURETHRAL NEPHROLITHOTRIPSY

disintegrated to particles of less than 5 mm. in diameter the procedure was considered successful. Although the rates free of stone in our series when the patient was discharged from the hospital were 52. 9 and 47.1 % for complete and partial staghorn calculi, respectively, we presume that 88.2% of those with particles of less than 5 mm. in diameter would eventually be free of stone. On the other hand, Schulze and associates reported that 32 of 87 patients (36.8%) were free of stone when they were discharged from the hospital after combined percutaneous lithotripsy and ESWL, although in 38 other patients (43.7%) the stone was disintegrated to small particles less than 3 mm. in diameter. 10 Obviously, a state without stones when the patient leaves the hospital is desirable. However, disintegration of a large stone into smaller particles with a less invasive method is equally important, since patients eventually would become free of stones. According to Kahnoski and associates the average hospital stay was 17 days for ESWL monotherapy, and 14.2 days for combined percutaneous and ESWL treatment. 8 Schulze and associates reported an average hospital stay of 19 days for the combination therapy, 10 which is much shorter compared to 37.5 days of our series. However, since our medical insurance system and other circumstances are different from theirs, it is difficult to make reasonable comparison regarding those data. A device is desirable that prevents increased pelvic pressure and disintegrates hard stones that cannot be treated by current electrohydraulic lithotripsy without tissue injury. Prof. J. Patrick Barron, St. Marianna University School of Medicine, assisted in reviewing the English language.

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97, 1988. 2. Miller, K., Bachor, R. and Hautmann, R.: Percutaneous nephrolithotomy and extracorporeal shock wave lithotripsy versus ureteral stent and ESWL for the treatment of large renal calculi and staghorn calculi-a prospective randomized study: preliminary results. J. Endourol., 2: 131, 1988. 3. Aso, Y., Ohtawara, Y., Fukuta, K., Sudoko, H., Nakano, M., Ushiyama, M., Ohta, N., Suzuki, K. and Tajima, A.: Operative fiberoptic nephroureteroscopy: removal of upper ureteral and renal calculi. J. Urol., 137: 629, 1987. 4. Aso, Y., Takayasu, H., Ohta, N. and Tajima, A.: Flexible ureterorenoscopy. Urol. Clin. N. Amer., 15: 329, 1988. 5. Patterson, D. E., Segura, J. W. and LeRoy, A. J.: Long-term followup of patients treated by percutaneous ultrasonic lithotripsy for struvite staghorn calculi. J. Endourol., l: 177, 1987. 6. Drach, G. W., Dretler, S., Fair, W., Finlayson, B., Gillenwater, J., Griffith, D., Lingeman, J. and Newman, D.: Report of the United States cooperative study of extracorporeal shock wave lithotripsy. J. Urol., 135: 1127, 1986. 7. Eisenberger, F., Rassweiler, J., Bub, P., Kallert, B. and Miller, K.: Differentiated approach to staghorn calculi using extra-corporeal shock wave lithotripsy and percutaneous nephrolithotomy: an analysis of 151 consecutive cases. World J. Urol., 5: 248, 1987. 8. Kahnoski, R. J., Lingeman, J.E., Coury, T. A., Steele, R. E. and Mosbaugh, P. G.: Combined percutaneous and extracorporeal shock wave lithotripsy for staghorn calculi: an alternative to anatrophic nephrolithotomy. J. Urol., 135: 679, 1986. 9. Snyder, J. A. and Smith, A. D.: Staghorn calculi: percutaneous extraction versus anatrophic nephrolithotomy. J. Urol., 136: 351, 1986. 10. Schulze, H., Hertle, L., Graff, J., Funke, P.-J. and Senge, T.: Combined treatment of branched calculi by percutaneous nephrolithotomy and extracorporeal shock wave lithotripsy. J. Urol., 135: 1138, 1986.