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Self-Retained Internal Ureteral Stents: A New Approach
0022-534 7/78/1196-0731$02. 00/0 THE JOURNAL OF UROWGY
Copyright © 1978 by The Williams & Wilkins Co.
SELF-RETAINED INTERNAL URETERAL STENTS: A NEW APPROACH THOMAS W. HEPPERLEN,* HALK. MARDISt
AND
HENRY KAMMANDEL
From the Department of Urology, Nebraska Methodist Hospital, Omaha, Nebraska
ABSTRACT
Definitive surgical treatment of ureteral obstruction may not be appropriate in patients with advanced malignancy, complex benign ureteral disease or even simple obstructive disease accompanied by unacceptable operative risk. Endoscopic placement of self-retained internal ureteral catheters (stents) offers satisfactory relief for many of these patients. A new 6F pigtail ureteral stent and placement technique are described. These stents are placed easily, effective and well tolerated for short-term and long-term drainage in selected patients with ureteral obstruction. The ideal ureteral stent would be totally internal, well tolerated, radiopaque, non-reactive, resistant to crystalloid encrustation, placed easily and removed endoscopically, and capable of maintaining its position with satisfactory drainage. A new ureteral stent and placement technique that approximate these goals are described. Pigtail stents are available, pre-sterilized, in lengths from 24 to 30 cm. (in 1 cm. increments) with matching components. A set consists of the 6F polyethylene stent with multiple apertures and distal flange, 6F whistle-tip ureteral catheter, 6F open end stent pusher and teflon coated wire guide with a silver mark to indicate ureteral catheter length. :j:
flange toward the orifice. Ideally, the stent is placed with the pigtail curled in the upper calix and the distal end protruding at least 1 cm. into the bladder (fig. 2). Superior calix positioning is not difficult, since most patients have advanced nephrosis. In patients with lesser degrees of upper tract dilatation it is occasionally desirable to anchor the stent in the upper renal pelvis (fig. 3). Final adjustment is made with an endoscopic forcep or the stent pusher prior to removal of the cystoscope. If the position of the stent selected is unsatis factory for any reason, it should be removed immediately and replaced with a more appropriate length. Fluoroscopy shortens the time required for placement and is useful but not mandatory; standard radiography will suffice.
TECHNIQUE RESULTS
Endoscopic placement of the 6F pigtail stent requires passage of a 3F (0.038 inch) 145 cm. spring wire guide beyond the ureteral obstruction into the upper collecting system (fig. 1). The 6F whistle-tip ureteral catheter should be passed first, demonstrating ureteral compliance at the obstructing point and allowing complete evaluation of the upper system by ureteropyelography. A cystoscope with a large catheterizing aperture must be used. The guide wire is introduced through the lumen of the ureteral catheter to the silver mark (equivalent to the length of the catheter). The catheter is then withdrawn through the cystoscope, maintaining the guide wire in position with the flexible at the selected anchor point. In some circumstances it is appropriate to pass the guide wire alone, having first evaluated the upper system by occlusive ureteropyelography or passage of a 3F ureteral catheter. The length of stent to be used (usually 24 to 30 cm.) is estimated by measuring the distance from the uppermost area of the collecting system to the ureteral orifice, adding 1 to 2 cm. for protrusion into the bladder. This measurement is determined from a ureteropyelogram and by noting the markings on the ureteral catheter. The stent is inserted over the guide wire, straightening its and advanced through the cystoscope using the stent (6F open end catheter). The stent readily follows the guide wire into the ureter. Advancement is complete when the tip of the stent is at the anchor point and the distal flange is approximately 3 cm. from the ureteral orifice. The guide wire is withdrawn under cystoscopic observation, maintaining the stent position with the stent pusher. The pigtail tip spontaneously anchoring the stent and drawing the distal
Our observations are from an experience with this technique in 25 patients with unilateral and bilateral uretera.l obstruction (see table). Endoscopic placement was successful in 23 patients, while open surgical placement was uc,,"""cu in 2. In 5 patients with bilateral obstruction the stent could placed only in 1 ureter. Several additional patients were
Accepted for publication July 8, 1977. Read at annual meeting of American Urological Association, Chicago, Illinois, April 24-28, 1977. * Current address: Plaza Urological, P.C., 2928 Hamilton Blvd., Sioux City, Iowa 51104. t Requests for reprints: Suite 407, 8300 Dodge, Omaha, Nebraska 68114. :j:
Cook Inc., P.O. Box 489, Bloomington, Indiana 47401.
Fm. 1. Technique of stent placement 731
732
HEPPERLEN, MARDIS AND KAMMANDEL
clinical results. One patient with obstructive pyelonephritis required a nephrectomy within 1 month of stent placement because of renal cortical abscesses. Successful stent maintenance in the other 24 patients ranges from 2 to 24 months, with an average duration of 8 months. Spontaneous expulsion has not occurred in our patients. DISCUSSION
N ephrostomy or ureterostomy drainage has been a standard but controversial form of palliative drainage for the cancer patient with ureteral obstruction for many years. 1• 2 The physician often hesitates to produce additional operative morbidity and an external tube diversion is a disagreeable situation for all concerned. Nevertheless, symptomatic ureteral obstruction may demand correction and the restoration of drainage in the uremic patient may allow time for beneficial cancer therapy. Patients with benign disease may present complex ureteral obstruction defying correction. Surgical treatment of relatively simple types of ureteral obstruction may not be possible in patients with high operative risk from concomitant disease. The endoscopic placement of a ureteral stent is a welcome solution for many of these patients and their physicians. Various types of stents and placement techniques have been described. a--s Even the most elaborate of these have associated complications. 9 • 10 We find the Gibbons stent8 to be frustrating to insert despite methods developed to simplify its use. 11 We believe the pigtail stent offers advantages over other types of stents. The prime advantage is a remarkable ease of insertion once the guide wire is in place. The variety of lengths available allows one to match closely the stent to the configuration of the involved upper urinary system. The Fm. 2. Stent coil in upper calix. IVP 10 months after placement of pigtail coil maintains the stent position effectively and no stent in solitary obstructed kidney (adenocarcinoma prostate). spontaneous expulsion has occurred during 192 stent-months offollowup in our patients. Effective long-term drainage is the rule even with advanced degrees of obstructive disease (fig. 4). Problems associated with ureteral stent drainage include proximal migration above the orifice, infection, crystalloid encrustation, reflux, hematuria, trigone erosion and inadequate drainage. 3 • 9 • 10 Proximal migration does not necessarily lead to loss of stent effectiveness but complicates retrieval and replacement should this be indicated. Meticulous pigtail stent positioning with the coil in the uppermost part of the collecting system and the flange protruding at least 1 cm. into the bladder will minimize this problem. Chronic infection has persisted in 2 patients with pre-existent calculi and urosepsis and has developed in 4 originally uninfected patients. These infections have been unresponsive to antibiotic therapy but have not produced significant morbidity. Crystalloid encrustation seems inevitable on long-term urinary tract catheters. Microscopic encrustation has been demonstrated on all stents that we have examined after several months of use, even without concomitant infection. The degree of encrustation has been minor. Our first patient with multiple pre-existent calculi, hypercalciuria (prednisone therapy) and chronic infection has shown no gross encrustation during 24 months of Fm. 3. Stent coil in renal pelvis. IVP 18 months after placement of stent to correct post-surgical obstruction (adenocarcinoma colon) with ureterocutaneous fistula.
considered to be candidates for this procedure but the stent could not be placed endoscopically and open surgical placement was not warranted. Successful placement of the stent resulted in prompt relief of ureteral obstruction in all instances. The recovery of satisfactory renal function and maintenance of drainage were documented by excretory urography (IVP) in 22 patients. Two patients were not available for followup IVP but had good
Diagnosis in 25 patients with ureteral obstruction relieved by stent No. Cases Malignant neoplasm, 19 patients: Prostate Uterus Colon Bladder Ovary
Non-malignant, 6 patients: Ureteral stone (complicated) Ureteral stricture (postop.) Retroperitoneal fibrosis U reterovaginal fistula
6 6 5
1 1 3 1 1 1
SELF-RETAINED INTERNAL URETERAL STENTS
Fm. 4. A, bilateral ureteral obstruction from subtrigonal extension of previously treated prostatic adenocarcinoma in 65-year-old man with uremic syndrome. B, stent could be passed only on right side. IVP 9 months after stent insertion shows maintenance of good drainage from right kidney. Blood urea nitrogen and creatinine remain normal after stent drainage.
observation. Our experience suggests that crystalloid encrustation may be less of a problem on the polyethylene stents than on various silicone stents that we have used in similar circumstances. Perhaps the efficient drainage through and around these 6F stents is a protective factor. Our experience with the latter 4 problems has been acceptable clinically and is similar to that of others. 3 • 8 High fluid intake should be encouraged in all stented patients. Adjunctive medications to promote solubility of urinary crystalloids, urinary acidifiers and prophylactic antimicrobials may be warranted, although many of our patients have done well without them. It is important to follow the patient closely throughout the duration of stent maintenance. The "ideal" ureteral stent has yet to be developed and the placement of a foreign body within the urinary system cannot be undertaken lightly. Although complications have been infrequent and minor, major problems could develop. Therefore, the use of a stent for long-term drainage should be limited to patients with clinical situations that justify the risk of these complications. We believe the benefits outweigh the risks in many patients and the pigtail stent will be a useful adjunct in the management of obstructive ureteral pathology. REFERENCES
1. Grabstald, H. and McPhee, M.: Nephrostomy and the cancer patient. South. Med. J., 66: 217, 1973. 2. Brin, E. N., Schiff, M., Jr. and Weiss, R. M.: Palliative urinary diversion for pelvic malignancy. J. Urol., 113: 619, 1975. 3. Zimskind, P. D., Fetter, T. R. and Wilkerson, J. L.: Clinical use of long-term indwelling silicone rubber ureteral splints inserted cystoscopically. J. Urol., 97: 840, 1967. 4. Marmar, J. L.: The management of ureteral obstruction with silicone rubber splint catheters. J. Urol., 104: 386, 1970. 5. Orikasa, S., Tsuji, I., Siba, T. and Ohasha, N.: A new technique for transurethral insertion of a silicone rubber tube into an
obstructed ureter. J. Urol., 110: 184, 1973. 6. Gibbons, R. P., Mason, J. T. and Correa, R. J., Jr.: Experience with indwelling silicone rubber ureteral catheters. J. Urol., 111: 594, 1974. 7. Pais, V. M., Spellman, R. M., Stiles, R. E. and Mahoney, S. A.: Internal ureteral splints. Urology, 5: 32, 1975. 8. Gibbons, R. P., Correa, R. J., Jr., Cummings, K. B. and Mason, J. T.: Experience with indwelling ureteral stent catheters. J. Urol., 115: 22, 1976. 9. Schneider, R. E., DePauw, A. P., Montie, J.E. and Thompson, I. M.: Problems associated with Gibbons ureteral catheter. Urology, 8: 243, 1976. 10. Niendorf, D. C. and Kamhi, B.: Retrieval of indwelling ureteral stent utilizing Fogarty catheter. Urology, 6: 622, 1975. 11. Danoff, D. S.: The Gibbons indwelling silicone ureteral stent catheter. J. Urol., 117: 33, 1977.
EDITORIAL COMMENT The ureteral stent has proved to be a valuable addition to the urological armamentarium. McCullough was the first to describe the use of a stent suspended from the kidney using material with a pigtail memory (polyethylene). 1 The described experience with these polyethylene stents is quite favorable. However, a higher infection rate and the inability to eradicate infection that occurs may be disadvantages of the polyethylene stent compared to a stent made of silicone rubber. 2 Proper length is quite critical with the suspended stent to avoid annoying symptoms of trigonal irritation or migration upward above the ureteral orifice. Placement of any ureteral stent requires patience and is best aided by the initial passage of a ureteral catheter or bougie up to the size of the stent to be used. If dilation to stent size is not possible a small ureteral catheter indwelling for 3 to 4 days will soften the area of obstruction, simplifying stent insertion. Robert P. Gibbons The Mason Clinic Seattle, Washington
Copyright © 1978 by The Williams & Wilkins Co.
SELF-RETAINED INTERNAL URETERAL STENTS: A NEW APPROACH THOMAS W. HEPPERLEN,* HALK. MARDISt
AND
HENRY KAMMANDEL
From the Department of Urology, Nebraska Methodist Hospital, Omaha, Nebraska
ABSTRACT
Definitive surgical treatment of ureteral obstruction may not be appropriate in patients with advanced malignancy, complex benign ureteral disease or even simple obstructive disease accompanied by unacceptable operative risk. Endoscopic placement of self-retained internal ureteral catheters (stents) offers satisfactory relief for many of these patients. A new 6F pigtail ureteral stent and placement technique are described. These stents are placed easily, effective and well tolerated for short-term and long-term drainage in selected patients with ureteral obstruction. The ideal ureteral stent would be totally internal, well tolerated, radiopaque, non-reactive, resistant to crystalloid encrustation, placed easily and removed endoscopically, and capable of maintaining its position with satisfactory drainage. A new ureteral stent and placement technique that approximate these goals are described. Pigtail stents are available, pre-sterilized, in lengths from 24 to 30 cm. (in 1 cm. increments) with matching components. A set consists of the 6F polyethylene stent with multiple apertures and distal flange, 6F whistle-tip ureteral catheter, 6F open end stent pusher and teflon coated wire guide with a silver mark to indicate ureteral catheter length. :j:
flange toward the orifice. Ideally, the stent is placed with the pigtail curled in the upper calix and the distal end protruding at least 1 cm. into the bladder (fig. 2). Superior calix positioning is not difficult, since most patients have advanced nephrosis. In patients with lesser degrees of upper tract dilatation it is occasionally desirable to anchor the stent in the upper renal pelvis (fig. 3). Final adjustment is made with an endoscopic forcep or the stent pusher prior to removal of the cystoscope. If the position of the stent selected is unsatis factory for any reason, it should be removed immediately and replaced with a more appropriate length. Fluoroscopy shortens the time required for placement and is useful but not mandatory; standard radiography will suffice.
TECHNIQUE RESULTS
Endoscopic placement of the 6F pigtail stent requires passage of a 3F (0.038 inch) 145 cm. spring wire guide beyond the ureteral obstruction into the upper collecting system (fig. 1). The 6F whistle-tip ureteral catheter should be passed first, demonstrating ureteral compliance at the obstructing point and allowing complete evaluation of the upper system by ureteropyelography. A cystoscope with a large catheterizing aperture must be used. The guide wire is introduced through the lumen of the ureteral catheter to the silver mark (equivalent to the length of the catheter). The catheter is then withdrawn through the cystoscope, maintaining the guide wire in position with the flexible at the selected anchor point. In some circumstances it is appropriate to pass the guide wire alone, having first evaluated the upper system by occlusive ureteropyelography or passage of a 3F ureteral catheter. The length of stent to be used (usually 24 to 30 cm.) is estimated by measuring the distance from the uppermost area of the collecting system to the ureteral orifice, adding 1 to 2 cm. for protrusion into the bladder. This measurement is determined from a ureteropyelogram and by noting the markings on the ureteral catheter. The stent is inserted over the guide wire, straightening its and advanced through the cystoscope using the stent (6F open end catheter). The stent readily follows the guide wire into the ureter. Advancement is complete when the tip of the stent is at the anchor point and the distal flange is approximately 3 cm. from the ureteral orifice. The guide wire is withdrawn under cystoscopic observation, maintaining the stent position with the stent pusher. The pigtail tip spontaneously anchoring the stent and drawing the distal
Our observations are from an experience with this technique in 25 patients with unilateral and bilateral uretera.l obstruction (see table). Endoscopic placement was successful in 23 patients, while open surgical placement was uc,,"""cu in 2. In 5 patients with bilateral obstruction the stent could placed only in 1 ureter. Several additional patients were
Accepted for publication July 8, 1977. Read at annual meeting of American Urological Association, Chicago, Illinois, April 24-28, 1977. * Current address: Plaza Urological, P.C., 2928 Hamilton Blvd., Sioux City, Iowa 51104. t Requests for reprints: Suite 407, 8300 Dodge, Omaha, Nebraska 68114. :j:
Cook Inc., P.O. Box 489, Bloomington, Indiana 47401.
Fm. 1. Technique of stent placement 731
732
HEPPERLEN, MARDIS AND KAMMANDEL
clinical results. One patient with obstructive pyelonephritis required a nephrectomy within 1 month of stent placement because of renal cortical abscesses. Successful stent maintenance in the other 24 patients ranges from 2 to 24 months, with an average duration of 8 months. Spontaneous expulsion has not occurred in our patients. DISCUSSION
N ephrostomy or ureterostomy drainage has been a standard but controversial form of palliative drainage for the cancer patient with ureteral obstruction for many years. 1• 2 The physician often hesitates to produce additional operative morbidity and an external tube diversion is a disagreeable situation for all concerned. Nevertheless, symptomatic ureteral obstruction may demand correction and the restoration of drainage in the uremic patient may allow time for beneficial cancer therapy. Patients with benign disease may present complex ureteral obstruction defying correction. Surgical treatment of relatively simple types of ureteral obstruction may not be possible in patients with high operative risk from concomitant disease. The endoscopic placement of a ureteral stent is a welcome solution for many of these patients and their physicians. Various types of stents and placement techniques have been described. a--s Even the most elaborate of these have associated complications. 9 • 10 We find the Gibbons stent8 to be frustrating to insert despite methods developed to simplify its use. 11 We believe the pigtail stent offers advantages over other types of stents. The prime advantage is a remarkable ease of insertion once the guide wire is in place. The variety of lengths available allows one to match closely the stent to the configuration of the involved upper urinary system. The Fm. 2. Stent coil in upper calix. IVP 10 months after placement of pigtail coil maintains the stent position effectively and no stent in solitary obstructed kidney (adenocarcinoma prostate). spontaneous expulsion has occurred during 192 stent-months offollowup in our patients. Effective long-term drainage is the rule even with advanced degrees of obstructive disease (fig. 4). Problems associated with ureteral stent drainage include proximal migration above the orifice, infection, crystalloid encrustation, reflux, hematuria, trigone erosion and inadequate drainage. 3 • 9 • 10 Proximal migration does not necessarily lead to loss of stent effectiveness but complicates retrieval and replacement should this be indicated. Meticulous pigtail stent positioning with the coil in the uppermost part of the collecting system and the flange protruding at least 1 cm. into the bladder will minimize this problem. Chronic infection has persisted in 2 patients with pre-existent calculi and urosepsis and has developed in 4 originally uninfected patients. These infections have been unresponsive to antibiotic therapy but have not produced significant morbidity. Crystalloid encrustation seems inevitable on long-term urinary tract catheters. Microscopic encrustation has been demonstrated on all stents that we have examined after several months of use, even without concomitant infection. The degree of encrustation has been minor. Our first patient with multiple pre-existent calculi, hypercalciuria (prednisone therapy) and chronic infection has shown no gross encrustation during 24 months of Fm. 3. Stent coil in renal pelvis. IVP 18 months after placement of stent to correct post-surgical obstruction (adenocarcinoma colon) with ureterocutaneous fistula.
considered to be candidates for this procedure but the stent could not be placed endoscopically and open surgical placement was not warranted. Successful placement of the stent resulted in prompt relief of ureteral obstruction in all instances. The recovery of satisfactory renal function and maintenance of drainage were documented by excretory urography (IVP) in 22 patients. Two patients were not available for followup IVP but had good
Diagnosis in 25 patients with ureteral obstruction relieved by stent No. Cases Malignant neoplasm, 19 patients: Prostate Uterus Colon Bladder Ovary
Non-malignant, 6 patients: Ureteral stone (complicated) Ureteral stricture (postop.) Retroperitoneal fibrosis U reterovaginal fistula
6 6 5
1 1 3 1 1 1
SELF-RETAINED INTERNAL URETERAL STENTS
Fm. 4. A, bilateral ureteral obstruction from subtrigonal extension of previously treated prostatic adenocarcinoma in 65-year-old man with uremic syndrome. B, stent could be passed only on right side. IVP 9 months after stent insertion shows maintenance of good drainage from right kidney. Blood urea nitrogen and creatinine remain normal after stent drainage.
observation. Our experience suggests that crystalloid encrustation may be less of a problem on the polyethylene stents than on various silicone stents that we have used in similar circumstances. Perhaps the efficient drainage through and around these 6F stents is a protective factor. Our experience with the latter 4 problems has been acceptable clinically and is similar to that of others. 3 • 8 High fluid intake should be encouraged in all stented patients. Adjunctive medications to promote solubility of urinary crystalloids, urinary acidifiers and prophylactic antimicrobials may be warranted, although many of our patients have done well without them. It is important to follow the patient closely throughout the duration of stent maintenance. The "ideal" ureteral stent has yet to be developed and the placement of a foreign body within the urinary system cannot be undertaken lightly. Although complications have been infrequent and minor, major problems could develop. Therefore, the use of a stent for long-term drainage should be limited to patients with clinical situations that justify the risk of these complications. We believe the benefits outweigh the risks in many patients and the pigtail stent will be a useful adjunct in the management of obstructive ureteral pathology. REFERENCES
1. Grabstald, H. and McPhee, M.: Nephrostomy and the cancer patient. South. Med. J., 66: 217, 1973. 2. Brin, E. N., Schiff, M., Jr. and Weiss, R. M.: Palliative urinary diversion for pelvic malignancy. J. Urol., 113: 619, 1975. 3. Zimskind, P. D., Fetter, T. R. and Wilkerson, J. L.: Clinical use of long-term indwelling silicone rubber ureteral splints inserted cystoscopically. J. Urol., 97: 840, 1967. 4. Marmar, J. L.: The management of ureteral obstruction with silicone rubber splint catheters. J. Urol., 104: 386, 1970. 5. Orikasa, S., Tsuji, I., Siba, T. and Ohasha, N.: A new technique for transurethral insertion of a silicone rubber tube into an
obstructed ureter. J. Urol., 110: 184, 1973. 6. Gibbons, R. P., Mason, J. T. and Correa, R. J., Jr.: Experience with indwelling silicone rubber ureteral catheters. J. Urol., 111: 594, 1974. 7. Pais, V. M., Spellman, R. M., Stiles, R. E. and Mahoney, S. A.: Internal ureteral splints. Urology, 5: 32, 1975. 8. Gibbons, R. P., Correa, R. J., Jr., Cummings, K. B. and Mason, J. T.: Experience with indwelling ureteral stent catheters. J. Urol., 115: 22, 1976. 9. Schneider, R. E., DePauw, A. P., Montie, J.E. and Thompson, I. M.: Problems associated with Gibbons ureteral catheter. Urology, 8: 243, 1976. 10. Niendorf, D. C. and Kamhi, B.: Retrieval of indwelling ureteral stent utilizing Fogarty catheter. Urology, 6: 622, 1975. 11. Danoff, D. S.: The Gibbons indwelling silicone ureteral stent catheter. J. Urol., 117: 33, 1977.
EDITORIAL COMMENT The ureteral stent has proved to be a valuable addition to the urological armamentarium. McCullough was the first to describe the use of a stent suspended from the kidney using material with a pigtail memory (polyethylene). 1 The described experience with these polyethylene stents is quite favorable. However, a higher infection rate and the inability to eradicate infection that occurs may be disadvantages of the polyethylene stent compared to a stent made of silicone rubber. 2 Proper length is quite critical with the suspended stent to avoid annoying symptoms of trigonal irritation or migration upward above the ureteral orifice. Placement of any ureteral stent requires patience and is best aided by the initial passage of a ureteral catheter or bougie up to the size of the stent to be used. If dilation to stent size is not possible a small ureteral catheter indwelling for 3 to 4 days will soften the area of obstruction, simplifying stent insertion. Robert P. Gibbons The Mason Clinic Seattle, Washington