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Calcification of Ureteral Stent Treated by extracorporeal Shock Wave Lithotripsy
0022~f347 /86/1366-1297$02.00/0 Vol
THE JO~':~,NA~. OP UROLOGY
Copyr:ght (<; 1986 by '::'he Williame, & Wi!kin_s C8_
Decembe: in U.S.A.
CALCIFICATION OF URETERAL STENT TREATED BY EXTRACORPOREAL SHOCK WAVE LITHOTRIPSY ANDREI N. LUPU, GERHARD J. FUCHS
AND
CHRISTIAN G. CHAUSSY
From the Department of Surgery, Division of Urology, UCLA School of Medicine, Los Angeles, California
ABSTRACT
A patient with stones presented with large calcifications of the J ends of a Double-J* stent that had been placed in the ureter for an obstructing ureteral stone 1 month previously. The J end located in the renal pelvis was treated with extracorporeal shock wave lithotripsy and the calcification was disintegrated completely. This noninvasive procedure appears to be the method of choice in the treatment of such complications. The use of extracorporeal shock wave lithotripsy (ESWL) in the treatment of ureteral stones has led to new management strategies. 1 - 3 In the era preceding ESWL stone basketing ureterolithotripsy and open ureterolithotomy were the most commonly used methods in the treatment of ureteral calculi. Presently, stone repositioning in the upper collecting system and placement of a Double-J stent to prevent antegrade migration of the calculus are the first steps taken before elective ESWL At times patients with a stent wait for a longer period for definitive treatment. Under these circumstances it is not uncommon to find at the time of stent removal small calcific deposits attached to the stent. 4 We report a case in which large calcific deposits were found at both ends of the stent. The calcifications attached to the J end located in the renal pelvis were treated by ESWL concomitantly with the native stones and were disintegrated completely. The stent was removed with the calcific deposits attached to the J end located in the bladder.
with supersaturated urine the stent acts as a foreign body and may cause secondary nidation and calcification, In a sense, the stent acts in vivo like the rat cartilage in the in vitro experiments of Thomas and Howard. 6 Spirnak and Resnick reported 5 similar instances in patients with stones. 7 In 3 of their patients the stent was removed endoscopically, whereas in 1 pyelolithotomy was necessary. One patient was not treated because of a multitude of complicating medical problems. The patient reported on by Abber and Kahn was treated with bilateral percutaneous nephrnstomy and the stones were dissolved using hemiacidrin irrigation. 8 It is noteworthy that in om case as well as in those reported
CASE REPORT
C. C., a 55-year-old woman, was admitted to the UCLA Clark Institute Lithotriptor Unit on November 21, 1985. She had an 8 mm. obstructive stone in the right ureter, a partial staghorn calculus in the upper pole of the right kidney and bilateral nephrocalcinosis. Because of the obstructive nature of the ureteral stone a Double-J silicone stent had been placed in the right ureter 1 month before hospitalization. Urine was not infected. The preoperative film of the demonstrated 2 large Calcification§ oHoo!,n.--1 to the 2 ends OI the Double-J, respectively (fig. 1), The calcified J end located in the renal was treated at the same time as the ureteral stone with For the ureteral stone shock waves at 23 kv. were used and for the calcified J 600 shock waves at 20 kv. were used. Immediately postoperatively the J end was cleared completely of calcific deposits (fig. 2, partial staghorn calculus required 2 separate ESWL treatments at 20 to 21 kv. for a total of 3,800 shock waves. A film of the kidneys, ureters and bladder 2 days after the last treatment revealed only nephrocalcinosis (fig. 2, B). DISCUSSION
In our experience 96.6 per cent of all ureteral stones can be treated successfully with ESWL in 1 session. 5 Retrograde stone manipulation and placement of a Double-J stent precede ESWL treatment, which can be scheduled at a later date on an elective basis. What is not fully appreciated is that in patients
Accepted for publication July 25, 1986. * Medical Engineering Corp., New York, New York.
FIG. L Preoperative film of kidneys, ureters and bladder shows position of ureteral stone (arrowhead).
1297
1298
LUPU, FUCHS AND CHAUSSY
by Spirnak and Resnick7 calcific deposits were seen only at the 2 ends of the stent located in the renal pelvis and in the bladder, respectively. The body of the catheter was completely free of calcific deposits, implying that in these cases urinary stasis had a major role in promoting calcification. With the increasing use of Double-J stents in patients with stones we expect similar events to occur more often. It is apparent that in this type of patient the stents should be left indwelling only for a short period. However, should such calcification occur, it is worthwhile to know that a noninvasive treatment is readily available. REFERENCES 1. Chaussy, C., Brendel, W. and Schmiedt, E.: Extracorporeally in-
2.
3. 4. 5. 6. 7. FIG. 2. Films of kidneys, ureters and bladder. A, position of disintegrated ureteral stone immediately postoperatively (arrowhead). Visible stone in upper ureter is disintegrated material from stent calcification. B, remaining calcifications represent nephrocalcinosis 2 days after last ESWL treatment.
8.
duced destruction of kidney stones by shock waves. Lancet, 2: 1265, 1980. Chaussy, C., Schmiedt, E., Jocham, D., Brendel, W., Forssmann, B. and Walther, V.: First clinical experience with extracorporeally induced destruction of kidney stones by shock waves. J. Urol., 127: 417, 1982. Chaussy, C. and Schmiedt, E.: Shock wave treatment for stones in the upper urinary tract. Urol. Clin. N. Amer., 10: 743, 1983. Finney, R. P.: Double-J and diversion stents. Urol. Clin. N. Amer., 9: 89, 1982. Lupu, A., Fuchs, G. and Chaussy, C.: A new approach to ureteral stone manipulation for ESWL. Endourology, 1: 13, 1986. Thomas, W. C., Jr. and Howard, J.E.: Studies on the mineralizing propensity of urine from patients with and without renal calculi. Trans. Ass. Amer. Phys., 72: 181, 1959. Spirnak, J.P. and Resnick, M. I.: Stone formation as a complication of indwelling ureteral stents: a report of 5 cases. J. Urol., 134: 349, 1985. Abber, J.C. and Kahn, R. I.: Pyelonephritis from severe incrustations on silicone ureteral stents: management. J. Urol., 130: 763, 1983.
THE JO~':~,NA~. OP UROLOGY
Copyr:ght (<; 1986 by '::'he Williame, & Wi!kin_s C8_
Decembe: in U.S.A.
CALCIFICATION OF URETERAL STENT TREATED BY EXTRACORPOREAL SHOCK WAVE LITHOTRIPSY ANDREI N. LUPU, GERHARD J. FUCHS
AND
CHRISTIAN G. CHAUSSY
From the Department of Surgery, Division of Urology, UCLA School of Medicine, Los Angeles, California
ABSTRACT
A patient with stones presented with large calcifications of the J ends of a Double-J* stent that had been placed in the ureter for an obstructing ureteral stone 1 month previously. The J end located in the renal pelvis was treated with extracorporeal shock wave lithotripsy and the calcification was disintegrated completely. This noninvasive procedure appears to be the method of choice in the treatment of such complications. The use of extracorporeal shock wave lithotripsy (ESWL) in the treatment of ureteral stones has led to new management strategies. 1 - 3 In the era preceding ESWL stone basketing ureterolithotripsy and open ureterolithotomy were the most commonly used methods in the treatment of ureteral calculi. Presently, stone repositioning in the upper collecting system and placement of a Double-J stent to prevent antegrade migration of the calculus are the first steps taken before elective ESWL At times patients with a stent wait for a longer period for definitive treatment. Under these circumstances it is not uncommon to find at the time of stent removal small calcific deposits attached to the stent. 4 We report a case in which large calcific deposits were found at both ends of the stent. The calcifications attached to the J end located in the renal pelvis were treated by ESWL concomitantly with the native stones and were disintegrated completely. The stent was removed with the calcific deposits attached to the J end located in the bladder.
with supersaturated urine the stent acts as a foreign body and may cause secondary nidation and calcification, In a sense, the stent acts in vivo like the rat cartilage in the in vitro experiments of Thomas and Howard. 6 Spirnak and Resnick reported 5 similar instances in patients with stones. 7 In 3 of their patients the stent was removed endoscopically, whereas in 1 pyelolithotomy was necessary. One patient was not treated because of a multitude of complicating medical problems. The patient reported on by Abber and Kahn was treated with bilateral percutaneous nephrnstomy and the stones were dissolved using hemiacidrin irrigation. 8 It is noteworthy that in om case as well as in those reported
CASE REPORT
C. C., a 55-year-old woman, was admitted to the UCLA Clark Institute Lithotriptor Unit on November 21, 1985. She had an 8 mm. obstructive stone in the right ureter, a partial staghorn calculus in the upper pole of the right kidney and bilateral nephrocalcinosis. Because of the obstructive nature of the ureteral stone a Double-J silicone stent had been placed in the right ureter 1 month before hospitalization. Urine was not infected. The preoperative film of the demonstrated 2 large Calcification§ oHoo!,n.--1 to the 2 ends OI the Double-J, respectively (fig. 1), The calcified J end located in the renal was treated at the same time as the ureteral stone with For the ureteral stone shock waves at 23 kv. were used and for the calcified J 600 shock waves at 20 kv. were used. Immediately postoperatively the J end was cleared completely of calcific deposits (fig. 2, partial staghorn calculus required 2 separate ESWL treatments at 20 to 21 kv. for a total of 3,800 shock waves. A film of the kidneys, ureters and bladder 2 days after the last treatment revealed only nephrocalcinosis (fig. 2, B). DISCUSSION
In our experience 96.6 per cent of all ureteral stones can be treated successfully with ESWL in 1 session. 5 Retrograde stone manipulation and placement of a Double-J stent precede ESWL treatment, which can be scheduled at a later date on an elective basis. What is not fully appreciated is that in patients
Accepted for publication July 25, 1986. * Medical Engineering Corp., New York, New York.
FIG. L Preoperative film of kidneys, ureters and bladder shows position of ureteral stone (arrowhead).
1297
1298
LUPU, FUCHS AND CHAUSSY
by Spirnak and Resnick7 calcific deposits were seen only at the 2 ends of the stent located in the renal pelvis and in the bladder, respectively. The body of the catheter was completely free of calcific deposits, implying that in these cases urinary stasis had a major role in promoting calcification. With the increasing use of Double-J stents in patients with stones we expect similar events to occur more often. It is apparent that in this type of patient the stents should be left indwelling only for a short period. However, should such calcification occur, it is worthwhile to know that a noninvasive treatment is readily available. REFERENCES 1. Chaussy, C., Brendel, W. and Schmiedt, E.: Extracorporeally in-
2.
3. 4. 5. 6. 7. FIG. 2. Films of kidneys, ureters and bladder. A, position of disintegrated ureteral stone immediately postoperatively (arrowhead). Visible stone in upper ureter is disintegrated material from stent calcification. B, remaining calcifications represent nephrocalcinosis 2 days after last ESWL treatment.
8.
duced destruction of kidney stones by shock waves. Lancet, 2: 1265, 1980. Chaussy, C., Schmiedt, E., Jocham, D., Brendel, W., Forssmann, B. and Walther, V.: First clinical experience with extracorporeally induced destruction of kidney stones by shock waves. J. Urol., 127: 417, 1982. Chaussy, C. and Schmiedt, E.: Shock wave treatment for stones in the upper urinary tract. Urol. Clin. N. Amer., 10: 743, 1983. Finney, R. P.: Double-J and diversion stents. Urol. Clin. N. Amer., 9: 89, 1982. Lupu, A., Fuchs, G. and Chaussy, C.: A new approach to ureteral stone manipulation for ESWL. Endourology, 1: 13, 1986. Thomas, W. C., Jr. and Howard, J.E.: Studies on the mineralizing propensity of urine from patients with and without renal calculi. Trans. Ass. Amer. Phys., 72: 181, 1959. Spirnak, J.P. and Resnick, M. I.: Stone formation as a complication of indwelling ureteral stents: a report of 5 cases. J. Urol., 134: 349, 1985. Abber, J.C. and Kahn, R. I.: Pyelonephritis from severe incrustations on silicone ureteral stents: management. J. Urol., 130: 763, 1983.