REMOVAL OF UPPER URINARY TRACT CALCULI WITH FLEXIBLE URETEROPYELOSCOPY DEMETRIUS H. BAGLEY, M.D. From the Departments of Urology and Radiology, Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania
ABSTRACT-Flexible ureteropyeloscopy is an endoscopic technique which can give access to the entire intrarenal collecting system. Retrieval instruments or lithotriptors, electro hydraulic or pulsed dye laser, can be employed. In 70 patients, 72 procedures were used to treat 77 calculi. The calculus could be reached in each patient. Previous treatment included shock-wave lithotripsy or attempts at repositioning and open surgical exploration. There were multiple calculi in 18 patients, and 3 patients weighed more than 300 pounds. Calculi were successfully removed or moved to the distal ureter in 62 of 77 cases (80.5 %). The success rate was better with mid or proximal ureteral stones and renal pelvic stones than distal calculi. In 21 patients lithotripsy was employed. Flexible ureteropyeloscopy can be utilized for the successful treatment of upper urinary tract calculi.
Ureteral calculi remain a major reason for ureteroscopy. Current high success rates have rendered ureteroscopy the technique of choice for the removal of distal calculi .1-3 Mid and upper ureteral calculi have been variously treated endoscopically or with shock-wave lithotripsy. The success rate with either technique leaves room for improvement. 4,5 Flexible ureteropyeloscopy offers an endoscopic technique with access to the entire upper urinary collecting system. It is of proven value in inspection and diagnosis within the ureter and intrarenal collecting system. 6,7 Flexible ureteroscopes have been used for retrieval of calculi, yet realization of their full potential has awaited development of small flexible lithotriptor probes which can fit through small working channels. 8 ,9 In the present series, patients with ureteral calculi presenting to or referred to our institution have been treated primarily with a flexible ureteroscope. Material and Methods During the initial phase of this study, only selected patients with ureteral calculi were
412
treated with the flexible ureteroscope. These patients included those in whom rigid ureteroscopy or ESWL failed or in whom other treatment modalities were contraindicated. After, our encouraging success, flexible ureteroscopy was used as the initial treatment modality in all patients with ureteral calculi. Several different flexible ureteroscopes were used in the study. Not all instruments were available at the same time, and, therefore, nO preference was made as to which flexible end,a< scope was utilized. When a calculus was dlSlodged into the intrarenal collecting system, a~ actively deflectable ureteropyeloscope was ut lized for its removal. All patients were trea~e in a retrograde fashion transurethrally With flexible ureteroscopes. Retrograde flexible ure~ teroscopy through a nephrostomy tract was n~ included. Patients were not included wh~n t intent of the procedure was specifically simp Y to push the calculus back into the kidney. Calculi were grasped with a 2.SF, three're pronged grasper or a 2F two-pronged WI grasper. When possible, the calculi were red trieved intact. Larger calculi were fra~me~t;f with an electrohydraulic lithotriptor usmg a
d
t
UROLOGY
/
MAY 1990
/
Ell 5
VOLUME XXXV. NuMB'
TABL"
,I
Flexible ureteroscolJes for stone removal
'_--------------
-------Instrument
Size (F)
~ly deflectable Circon. ACMI Circon, ACMI OlympUS Storz
9.8 8.5 10.8 10.5
Passively deflectable Baxler Microvasive, Van-Tec Microvasive, Van-Tec
7.0 6.0 8.5
-
probe or a pulsed dye laser lithotriptor using a 250-micron fiber. Major fragments of calculus were then retrieved with the graspers. A ureteral catheter or self-retaining stent was left within the ureter in all patients postoperatively. This was removed either at two days or one to two weeks, respectively. Technique
The flexible ureteroscope was passed into the -ureter using standard techniques. 1o The ureteral orifice was dilated as necessary.lI In each :case a O.038-inch straight, floppy-tipped guidewire was initially passed into the ureter to maintain access and remain in place as a safety guidewire. The endoscopes were passed into the orifice with stabilization through a rigid sheath, flexible sheath, or over a guidewire. Irrigation was maintained with physiologic saline. When the electrohydraulic lithotriptor was used, irrigation consisted of one sixth or one fifth normal saline only during the lithotripsy period. Results Retrograde flexible ureteroscopy was utilized in 72 procedures in 70 patients to treat 77 calculi at different locations. Multiple calculi located at a single anatomic site were considered a single calculus. It was possible to place the flexible endoscope to view the calculus in
TABLE II. Location Renal collecting system Proximal ureter Mid ureter Distal ureter
each patient. Forty-six of the patients were male, and 24 were female. The instruments employed are listed in Table I. General or spinal anesthesia was used in most patients. However, local anesthesia with intravenous sedation was employed in 12 patients. In these patients there were 13 calculi, 2 in the intrarenal collecting system, 3 in the proximal ureter, 7 in the mid ureter, and 1 in the distal ureter. The history of treatment was remarkable in that 15 patients had failed shock-wave lithotripsy or attempts at repositioning (Fig. 1). Two of these patients had failed two attempts at shock-wave lithotripsy, 1 had failed three attempts, and 1 had failed treatment with both shock-wave lithotripsy and open surgical exploration. There were multiple calculi at the same or different sites in 18 patients. Three patients weighed more than 300 pounds and were referred for endoscopy specifically because of their weight. Overall, calculi were successfully removed or repositioned for removal during the same endoscopic procedure with a rigid instrument in 62 (80.5 %) of 77 cases (Table II). The success was related to the location of the stones. Among 23 calculi located within the renal pelvis or the intrarenal collecting system, 20 were removed initially with the flexible endoscope or fragmented into small pieces to pass easily. An additional 2 calculi were removed to a location that could be treated with a rigid endoscope during the same procedure. In 1 patient the calculus was not removed. In comparison, among 13 calculi in the distal ureter only 6 were successfully removed. The remaining 7 were removed with a rigid endoscope during the same procedure. However, the flexible endoscope did not contribute to removal of the stone and, therefore, the flexible endoscopic procedure was not considered successful. In 21 patients the calculus was too large to be removed intact. Therefore, the calculus was
Results oj jlexible ureteroscopic treatment oj calculi Success Removed Moved
/
MAY 1990
I
Total
20
2
1
23
13 14 6
5 2
1 6 7
19 22 13
15
77
62 (80.5%)
UROLOGY
Failure
VOLUME XXXV, NUMBER 5
413
c
1. (A) Proximal right ureteral calculus treated in situ with ESWL after failure of repositioning and stenting. (B) Retrograde pyelogram demonstrates tortuosity of ureter and edema at level of calculus. (C) Flexible ureteroscope positioned at calculus with 3F EHL probe used for fragmentation. FIGURE
L, fragmented prior to removal. In 9 patients a pulsed dye laser was employed and in 12 an electrohydraulic lithotriptor. A similar success rate was seen with either technique. There was a difference in size of calculi that could be removed intact or by lithotripsy at any location. Slightly larger calculi could be removed intact from the distal ureter (Table III).
TABLE
414
III.
Comment Flexible ureteropyeloscopy now offers another modality for the treatment of urinary calculi. Rigid ureteroscopy has been extremel~ successful for the treatment of distal calculI with success rates routinely over 90 percent in all series.! 3 However, it has been less successful
Size of calculi (mm) treated with flexible ureteroscopes Location Mid
Stone
Renal
Proximal
Retrieved
4 x 5
3 x 4
4 x 5
4 x 6
Fragmented EHL Laser
5 x 9 7 x 8
8 x 8 6 x 10
6 x 7 8 x 11
5 x 7
CROLOGY
/
Distal Ureter
MAY l!)f)O
!
'L'\(llFH 5 VOLUME XXXV N '. '
· rcrno\'ing mid and proximal ureteral calculi
~~ith success rates in the 50-80 percent range.
Shock-wave lithotripsy has also been employed fll' the treatment of upper ureteral calculi. The ':lccess rate with this modality has been only s roximally 65 percent with calculi in situ but Pncreases to 80 percent after passage of a ure~eral catheter and to greater than 90 percent if the calculus is successfully pushed back into the intrarenal collecting system by endoscopic manipulation. 4.5 Flexible ureteroscopes can be passed above the level of the iliac vessels more easily than rigid instruments in males as well as females. There is often difficulty in negotiating the ureter at that point with the rigid endoscope. The flexible endoscopes are also generally smaller than the rigid working endoscopes and therefore require less dilation of the ureterovesical junction. Fully actively deflectable endoscopes with a working channel range in size from 8.5F to approximately 12F (Table I). The smallest instrument (8.5F) has a 2.5F channel which is adequate for some grasping instruments and for a laser fiber. There is also a prototype of a 1.9F electrohydraulic lithotriptor probe which was available at times and could be used through this endoscope. The larger instruments (from 9.8F to 12F) have channels of 3.6F or greater and therefore can accept all of the 3F working instruments. These now include baskets, graspers, and electrohydraulic lithotriptor probes. The flexible ureteroscopes do not accept a rigid ultrasound transducer. Therefore, the rigid endoscopes may be more efficient when removing calculi requiring fragmentation. 12 Calculi or fragments were grasped under vision through a flexible endoscope only with a reversible grasping technique. Wire-pronged graspers were usually employed since they could be released if the calculus could not be Withdrawn through a narrow portion of the ureter. In comparison, if a basket were used to retrieve a calculus, which then failed to pass t?rough a narrow segment, it might be very diffJ~ult to disengage the stone. We prefer to use Wire-pronged graspers for stone retrieval. .Flexible endoscopes can accept flexible lithotnptor instruments, the electrohydraulic probe, and the laser fiber. Both of these instruments are effective in fragmenting calculi,l314 They are more effective on more fragile stones, such as oxalate dihydrate'than the\! are \ . calcium I J Vlt 1 cystine or calcium oxalate monohydrate. IS
~IAY
1990
VOLlJME XXXV. :\U1\1BER .5
There is some difference in the fragmentation seen with the two techniques: the electrohydraulic cleaves the calculus into larger fragments which can be removed with graspers, while the pulsed dye laser forms smaller fragments which are difficult to grasp yet can be passed easily through the ureter. Among the patients treated in this series, both techniques were similarly effective. Initially in this study, patients with problem calculi were treated with the flexible ureteroscope. These included those who had failed shock-wave lithotripsy, patients with tortuous ureters, and those who had a calculus found during a diagnostic study. The success in these patients then prompted use in all patients with ureteral calculi. The results in patients in this study indicate the value of flexible ureteroscopy for removing calculi in the mid and upper ureter and its relative difficulty in the distal ureter. The major problem in using the flexible endoscope in the distal ureter was maintaining the scope within the ureter. It was difficult to keep the instrument in the distal ureter since the tip would often fall into the bladder, and it was difficult to reinsert into the orifice. Therefore, the major obstacle was maintaining the position of the endoscope. We use a rigid ureteroscope for treating calculi in the distal ureter. Flexible ureteroscopy has been particularly effective for treating calculi in the mid and upper ureter. In addition to our original application for stones that have failed shock-wave lithotripsy, those above tortuous portions of the ureter, and those found during diagnostic procedures, we have also added patients who require some other endoscopic procedure and impacted calculi as well as any lesions, which can be approached more easily with a flexible than a rigid endoscope and are thought to be treated best endoscopically. There is a very real role for flexible ureteral endoscopy for treating calculi within the kidney. Although shock-wave lithotripsy has an excellent success rate for treating stones within the kidney, the success for flexible endoscopy in this series is comparable. It should be noted, however, that these were relatively small stones treated either by retrieval or fragmentation. Flexible ureteropyeloscopy cannot be expected to replace shock-wave lithotripsy for treating renal calculi since it is technically more difficult and more invasive. However, it does offer the advantage of complete removal during one procedure without the need for following the
415
passage of fragments. It is particularly useful in patients who are having some endoscopic procedure such as ureteroscopic removal of a distal calculus or treatment of a ureteral stricture. Therefore, flexible ureteropyeloscopy appears to be an acceptable, and probably equivalent, treatment for renal calculi. 1025 Walnut Street Room 1112 Philadelphia, Pennsylvania 19107 References 1. Kahn RI: Endourological treatment of ureteral calculi. Ural 135: 239 (1986). . 2. Lingeman JE, ct al: Ureteral stone management: emerging concepts. JUral 135: 1172 (1986). 3. Seeger AR. Rittenberg MH, and Bagley DH: Ureteropyeloscopic removal of ureteral calculi, JUral 139: 1180 (1988). 4. Lingcman JE, et al: Management of upper ureteral calculi with extracorporeal shock-wave lithotripsy, J Urol 138: 720 (1987). ,5. Evans RJ, Wingfield DO, Morollo BA, and Jenkins AD:
416
Creteral stone manipulation before extracorporeal shock WaVe lithotripsy, J Frol 139: 3,) (1988). 6. Aso Y. et al: Usefulness of fiberoptic pyeloureterascopc in the diagnosis of thc upper urinary tract lesions, Urol lnt :39: 355 (1984). 7. Baglev OIl, Huffman JL, and LYon ES: Flexible IIrctcro. pyeloscopy: diagnosis and treatment in the upper urinary tract, ) Urol 138: 280 (1987). S. Prcminger GM. and Kennedy TJ: Creteral stone extraction utilizing nondeflectable flexible fiberaptic ureteroscopes, J En. dourol 1: 31 (19Si). 9. Aso Y, et al: Operative fiberoptic nephroureteroscopy: reo moval of upper ureteral and renal calculi, J Uro1137: 629 (1987). 10. Bagley DH: Ureteropveloscopy with flexible fiberoptic in. struments. in Huffman JL, Bagley DB, and Lyon ES (Eds): Ure. teroscopy, Philadelphia, WB Saunders, chap 10, 1988. I'll 131155. 11. Bagley OIl: Dilation of the ureterovesical junction and ureter, in Huffman JL, Bagley DB, and Lyon ES (Eds): Ureteros. copy, Philadelphia, \VB Saunders, chap 5. 1988, pp 51-72. 12. Chaussy C, et al: Transurethral ultrasonic urcterolitho. tripsy using a solid wire probe, Urology 29: 531 (198,). 13. Green OF, and Lytton B: Early experience with direct vi. sion electrohydraulic lithotripsy of ureteral calculi. J Urnl 133: 767 (1985). 14. Dretler SP: Techniques of laser lithotripsy, J Enclollrol21 123 (1988). 15. Dretler SP: Stone fragility, a new therapeutic distinction,], Urol 139: 1124 (1988).
UROLOGY
I
MAY 1990
I
'IllEn S
VOLUME XXXV, NU"
ABSTRACT-Flexible ureteropyeloscopy is an endoscopic technique which can give access to the entire intrarenal collecting system. Retrieval instruments or lithotriptors, electro hydraulic or pulsed dye laser, can be employed. In 70 patients, 72 procedures were used to treat 77 calculi. The calculus could be reached in each patient. Previous treatment included shock-wave lithotripsy or attempts at repositioning and open surgical exploration. There were multiple calculi in 18 patients, and 3 patients weighed more than 300 pounds. Calculi were successfully removed or moved to the distal ureter in 62 of 77 cases (80.5 %). The success rate was better with mid or proximal ureteral stones and renal pelvic stones than distal calculi. In 21 patients lithotripsy was employed. Flexible ureteropyeloscopy can be utilized for the successful treatment of upper urinary tract calculi.
Ureteral calculi remain a major reason for ureteroscopy. Current high success rates have rendered ureteroscopy the technique of choice for the removal of distal calculi .1-3 Mid and upper ureteral calculi have been variously treated endoscopically or with shock-wave lithotripsy. The success rate with either technique leaves room for improvement. 4,5 Flexible ureteropyeloscopy offers an endoscopic technique with access to the entire upper urinary collecting system. It is of proven value in inspection and diagnosis within the ureter and intrarenal collecting system. 6,7 Flexible ureteroscopes have been used for retrieval of calculi, yet realization of their full potential has awaited development of small flexible lithotriptor probes which can fit through small working channels. 8 ,9 In the present series, patients with ureteral calculi presenting to or referred to our institution have been treated primarily with a flexible ureteroscope. Material and Methods During the initial phase of this study, only selected patients with ureteral calculi were
412
treated with the flexible ureteroscope. These patients included those in whom rigid ureteroscopy or ESWL failed or in whom other treatment modalities were contraindicated. After, our encouraging success, flexible ureteroscopy was used as the initial treatment modality in all patients with ureteral calculi. Several different flexible ureteroscopes were used in the study. Not all instruments were available at the same time, and, therefore, nO preference was made as to which flexible end,a< scope was utilized. When a calculus was dlSlodged into the intrarenal collecting system, a~ actively deflectable ureteropyeloscope was ut lized for its removal. All patients were trea~e in a retrograde fashion transurethrally With flexible ureteroscopes. Retrograde flexible ure~ teroscopy through a nephrostomy tract was n~ included. Patients were not included wh~n t intent of the procedure was specifically simp Y to push the calculus back into the kidney. Calculi were grasped with a 2.SF, three're pronged grasper or a 2F two-pronged WI grasper. When possible, the calculi were red trieved intact. Larger calculi were fra~me~t;f with an electrohydraulic lithotriptor usmg a
d
t
UROLOGY
/
MAY 1990
/
Ell 5
VOLUME XXXV. NuMB'
TABL"
,I
Flexible ureteroscolJes for stone removal
'_--------------
-------Instrument
Size (F)
~ly deflectable Circon. ACMI Circon, ACMI OlympUS Storz
9.8 8.5 10.8 10.5
Passively deflectable Baxler Microvasive, Van-Tec Microvasive, Van-Tec
7.0 6.0 8.5
-
probe or a pulsed dye laser lithotriptor using a 250-micron fiber. Major fragments of calculus were then retrieved with the graspers. A ureteral catheter or self-retaining stent was left within the ureter in all patients postoperatively. This was removed either at two days or one to two weeks, respectively. Technique
The flexible ureteroscope was passed into the -ureter using standard techniques. 1o The ureteral orifice was dilated as necessary.lI In each :case a O.038-inch straight, floppy-tipped guidewire was initially passed into the ureter to maintain access and remain in place as a safety guidewire. The endoscopes were passed into the orifice with stabilization through a rigid sheath, flexible sheath, or over a guidewire. Irrigation was maintained with physiologic saline. When the electrohydraulic lithotriptor was used, irrigation consisted of one sixth or one fifth normal saline only during the lithotripsy period. Results Retrograde flexible ureteroscopy was utilized in 72 procedures in 70 patients to treat 77 calculi at different locations. Multiple calculi located at a single anatomic site were considered a single calculus. It was possible to place the flexible endoscope to view the calculus in
TABLE II. Location Renal collecting system Proximal ureter Mid ureter Distal ureter
each patient. Forty-six of the patients were male, and 24 were female. The instruments employed are listed in Table I. General or spinal anesthesia was used in most patients. However, local anesthesia with intravenous sedation was employed in 12 patients. In these patients there were 13 calculi, 2 in the intrarenal collecting system, 3 in the proximal ureter, 7 in the mid ureter, and 1 in the distal ureter. The history of treatment was remarkable in that 15 patients had failed shock-wave lithotripsy or attempts at repositioning (Fig. 1). Two of these patients had failed two attempts at shock-wave lithotripsy, 1 had failed three attempts, and 1 had failed treatment with both shock-wave lithotripsy and open surgical exploration. There were multiple calculi at the same or different sites in 18 patients. Three patients weighed more than 300 pounds and were referred for endoscopy specifically because of their weight. Overall, calculi were successfully removed or repositioned for removal during the same endoscopic procedure with a rigid instrument in 62 (80.5 %) of 77 cases (Table II). The success was related to the location of the stones. Among 23 calculi located within the renal pelvis or the intrarenal collecting system, 20 were removed initially with the flexible endoscope or fragmented into small pieces to pass easily. An additional 2 calculi were removed to a location that could be treated with a rigid endoscope during the same procedure. In 1 patient the calculus was not removed. In comparison, among 13 calculi in the distal ureter only 6 were successfully removed. The remaining 7 were removed with a rigid endoscope during the same procedure. However, the flexible endoscope did not contribute to removal of the stone and, therefore, the flexible endoscopic procedure was not considered successful. In 21 patients the calculus was too large to be removed intact. Therefore, the calculus was
Results oj jlexible ureteroscopic treatment oj calculi Success Removed Moved
/
MAY 1990
I
Total
20
2
1
23
13 14 6
5 2
1 6 7
19 22 13
15
77
62 (80.5%)
UROLOGY
Failure
VOLUME XXXV, NUMBER 5
413
c
1. (A) Proximal right ureteral calculus treated in situ with ESWL after failure of repositioning and stenting. (B) Retrograde pyelogram demonstrates tortuosity of ureter and edema at level of calculus. (C) Flexible ureteroscope positioned at calculus with 3F EHL probe used for fragmentation. FIGURE
L, fragmented prior to removal. In 9 patients a pulsed dye laser was employed and in 12 an electrohydraulic lithotriptor. A similar success rate was seen with either technique. There was a difference in size of calculi that could be removed intact or by lithotripsy at any location. Slightly larger calculi could be removed intact from the distal ureter (Table III).
TABLE
414
III.
Comment Flexible ureteropyeloscopy now offers another modality for the treatment of urinary calculi. Rigid ureteroscopy has been extremel~ successful for the treatment of distal calculI with success rates routinely over 90 percent in all series.! 3 However, it has been less successful
Size of calculi (mm) treated with flexible ureteroscopes Location Mid
Stone
Renal
Proximal
Retrieved
4 x 5
3 x 4
4 x 5
4 x 6
Fragmented EHL Laser
5 x 9 7 x 8
8 x 8 6 x 10
6 x 7 8 x 11
5 x 7
CROLOGY
/
Distal Ureter
MAY l!)f)O
!
'L'\(llFH 5 VOLUME XXXV N '. '
· rcrno\'ing mid and proximal ureteral calculi
~~ith success rates in the 50-80 percent range.
Shock-wave lithotripsy has also been employed fll' the treatment of upper ureteral calculi. The ':lccess rate with this modality has been only s roximally 65 percent with calculi in situ but Pncreases to 80 percent after passage of a ure~eral catheter and to greater than 90 percent if the calculus is successfully pushed back into the intrarenal collecting system by endoscopic manipulation. 4.5 Flexible ureteroscopes can be passed above the level of the iliac vessels more easily than rigid instruments in males as well as females. There is often difficulty in negotiating the ureter at that point with the rigid endoscope. The flexible endoscopes are also generally smaller than the rigid working endoscopes and therefore require less dilation of the ureterovesical junction. Fully actively deflectable endoscopes with a working channel range in size from 8.5F to approximately 12F (Table I). The smallest instrument (8.5F) has a 2.5F channel which is adequate for some grasping instruments and for a laser fiber. There is also a prototype of a 1.9F electrohydraulic lithotriptor probe which was available at times and could be used through this endoscope. The larger instruments (from 9.8F to 12F) have channels of 3.6F or greater and therefore can accept all of the 3F working instruments. These now include baskets, graspers, and electrohydraulic lithotriptor probes. The flexible ureteroscopes do not accept a rigid ultrasound transducer. Therefore, the rigid endoscopes may be more efficient when removing calculi requiring fragmentation. 12 Calculi or fragments were grasped under vision through a flexible endoscope only with a reversible grasping technique. Wire-pronged graspers were usually employed since they could be released if the calculus could not be Withdrawn through a narrow portion of the ureter. In comparison, if a basket were used to retrieve a calculus, which then failed to pass t?rough a narrow segment, it might be very diffJ~ult to disengage the stone. We prefer to use Wire-pronged graspers for stone retrieval. .Flexible endoscopes can accept flexible lithotnptor instruments, the electrohydraulic probe, and the laser fiber. Both of these instruments are effective in fragmenting calculi,l314 They are more effective on more fragile stones, such as oxalate dihydrate'than the\! are \ . calcium I J Vlt 1 cystine or calcium oxalate monohydrate. IS
~IAY
1990
VOLlJME XXXV. :\U1\1BER .5
There is some difference in the fragmentation seen with the two techniques: the electrohydraulic cleaves the calculus into larger fragments which can be removed with graspers, while the pulsed dye laser forms smaller fragments which are difficult to grasp yet can be passed easily through the ureter. Among the patients treated in this series, both techniques were similarly effective. Initially in this study, patients with problem calculi were treated with the flexible ureteroscope. These included those who had failed shock-wave lithotripsy, patients with tortuous ureters, and those who had a calculus found during a diagnostic study. The success in these patients then prompted use in all patients with ureteral calculi. The results in patients in this study indicate the value of flexible ureteroscopy for removing calculi in the mid and upper ureter and its relative difficulty in the distal ureter. The major problem in using the flexible endoscope in the distal ureter was maintaining the scope within the ureter. It was difficult to keep the instrument in the distal ureter since the tip would often fall into the bladder, and it was difficult to reinsert into the orifice. Therefore, the major obstacle was maintaining the position of the endoscope. We use a rigid ureteroscope for treating calculi in the distal ureter. Flexible ureteroscopy has been particularly effective for treating calculi in the mid and upper ureter. In addition to our original application for stones that have failed shock-wave lithotripsy, those above tortuous portions of the ureter, and those found during diagnostic procedures, we have also added patients who require some other endoscopic procedure and impacted calculi as well as any lesions, which can be approached more easily with a flexible than a rigid endoscope and are thought to be treated best endoscopically. There is a very real role for flexible ureteral endoscopy for treating calculi within the kidney. Although shock-wave lithotripsy has an excellent success rate for treating stones within the kidney, the success for flexible endoscopy in this series is comparable. It should be noted, however, that these were relatively small stones treated either by retrieval or fragmentation. Flexible ureteropyeloscopy cannot be expected to replace shock-wave lithotripsy for treating renal calculi since it is technically more difficult and more invasive. However, it does offer the advantage of complete removal during one procedure without the need for following the
415
passage of fragments. It is particularly useful in patients who are having some endoscopic procedure such as ureteroscopic removal of a distal calculus or treatment of a ureteral stricture. Therefore, flexible ureteropyeloscopy appears to be an acceptable, and probably equivalent, treatment for renal calculi. 1025 Walnut Street Room 1112 Philadelphia, Pennsylvania 19107 References 1. Kahn RI: Endourological treatment of ureteral calculi. Ural 135: 239 (1986). . 2. Lingeman JE, ct al: Ureteral stone management: emerging concepts. JUral 135: 1172 (1986). 3. Seeger AR. Rittenberg MH, and Bagley DH: Ureteropyeloscopic removal of ureteral calculi, JUral 139: 1180 (1988). 4. Lingcman JE, et al: Management of upper ureteral calculi with extracorporeal shock-wave lithotripsy, J Urol 138: 720 (1987). ,5. Evans RJ, Wingfield DO, Morollo BA, and Jenkins AD:
416
Creteral stone manipulation before extracorporeal shock WaVe lithotripsy, J Frol 139: 3,) (1988). 6. Aso Y. et al: Usefulness of fiberoptic pyeloureterascopc in the diagnosis of thc upper urinary tract lesions, Urol lnt :39: 355 (1984). 7. Baglev OIl, Huffman JL, and LYon ES: Flexible IIrctcro. pyeloscopy: diagnosis and treatment in the upper urinary tract, ) Urol 138: 280 (1987). S. Prcminger GM. and Kennedy TJ: Creteral stone extraction utilizing nondeflectable flexible fiberaptic ureteroscopes, J En. dourol 1: 31 (19Si). 9. Aso Y, et al: Operative fiberoptic nephroureteroscopy: reo moval of upper ureteral and renal calculi, J Uro1137: 629 (1987). 10. Bagley DH: Ureteropveloscopy with flexible fiberoptic in. struments. in Huffman JL, Bagley DB, and Lyon ES (Eds): Ure. teroscopy, Philadelphia, WB Saunders, chap 10, 1988. I'll 131155. 11. Bagley OIl: Dilation of the ureterovesical junction and ureter, in Huffman JL, Bagley DB, and Lyon ES (Eds): Ureteros. copy, Philadelphia, \VB Saunders, chap 5. 1988, pp 51-72. 12. Chaussy C, et al: Transurethral ultrasonic urcterolitho. tripsy using a solid wire probe, Urology 29: 531 (198,). 13. Green OF, and Lytton B: Early experience with direct vi. sion electrohydraulic lithotripsy of ureteral calculi. J Urnl 133: 767 (1985). 14. Dretler SP: Techniques of laser lithotripsy, J Enclollrol21 123 (1988). 15. Dretler SP: Stone fragility, a new therapeutic distinction,], Urol 139: 1124 (1988).
UROLOGY
I
MAY 1990
I
'IllEn S
VOLUME XXXV, NU"
