161
Percutaneous Renal Surgery, First Edition. Edited by Manoj Monga and Abhay Rane.
© 2014 John Wiley & Sons, Ltd. Published 2014 by John Wiley & Sons, Ltd.
Instrumentation and Surgical Technique: Step-by-Step Antegrade Ureteric StentingRavi KulkarniAshford and St Peter’s Hospitals, Chertsey, UK
Insertion of a ureteric stent is an “everyday” procedure
for urologists. Done for a wide variety of indications, it is
most frequently performed in a retrograde manner via
the cystoscope. The technique is well established. The
selection of guidewires, the stent diameter, design, and
length are determined by the underlying pathology,
patient habitus, and personal preference of the urologist.
The same procedure can be performed in an antegrade
manner in a selected cohort of patients and may become
necessary for a variety of reasons. The ureteric orifice
may be inaccessible due to invasion by malignancy [1].
Ureteric obstruction may be too severe to allow the
passage of a guidewire into the renal pelvis for a success-
ful retrograde stent insertion [2,3]. Such clinical
situations require insertion of a nephrostomy tube prior
to stenting.
Insertion of a nephrostomy tube becomes necessary
when upper tract obstruction is supravesical. Acute
renal failure due to bilateral ureteric obstruction that
cannot be relieved by retrograde stenting is a common
indication for bilateral nephrostomy tube insertion. This
may become imperative if the patient is acutely ill and
cannot be anesthetized for the insertion of a JJ stent.
Unilateral decompression of a ureter with a nephros-
tomy tube is necessary when the obstruction is severe or
complicated by sepsis or the patient has a solitary
functioning kidney. Other clinical settings when a
patient needs insertion of a nephrostomy prior to JJ stent
insertion are ureteric trauma (frequently iatrogenic)
[4–7], ureteric fistulas [8], and ureteric obstruction in
the presence of urinary diversion.
Another indication for antegrade stenting of the ureter
is following endopyelotomy for pelvi-ureteric junction
(PUJ) obstruction performed via a percutaneous route.
The insertion of a ureteric stent can be performed
when renal function has improved and sepsis settled [9].
Insertion of a JJ stent in an antegrade manner is a useful
technique in these clinical settings. It can be performed
under sedation in a radiology suite in selected patients
[10,11].
Principles and prerequisites
Although the technique of antegrade stenting can be
considered to be a simple reversal of the conventional
retrograde technique, there are important differences.
Insertion of a JJ stent is usually performed a few days after
insertion of a nephrostomy tube. However, it can be
performed as a primary procedure.
CHAPTER 1717
162 SECTION 2 Large Renal Calculi (Percutaneous Nephrolithotomy)
Patient preparation
It is essential to optimize the patient’s condition before
undertaking stenting. Renal function should be as normal
as possible. Sepsis should be fully treated. Prophylactic
antibiotic cover should be administered at least 1 h before
the procedure. The choice of antibiotic will be deter-
mined by the urine culture from the nephrostomy urine.
Hemogram and coagulation screen should be performed.
Long-acting anticoagulation medication should be
reversed and antiplatelet medications discontinued.
A written consent should be obtained from the patient.
It is important to ensure that a premenopausal female
patient is not pregnant as the procedure is performed
under fluoroscopic guidance.
Consideration should be given to the patient’s age,
comorbidity, and willingness to undergo the procedure
under local anesthesia. This is more significant if bilateral
stenting is to be performed. A general anesthetic may be
more appropriate in some patients in these settings.
The operating surgeon/radiologist should be aware
of the underlying pathology, patient comorbidity, and
previous surgical procedures on the urinary tract, espe-
cially urinary diversions.
The decision to remove or reinsert the nephrostomy
tube after successful stent insertion should be made
before commencing the procedure.
Equipment
The procedure can be performed in a radiology suite or a
fully equipped endourology theater with an image inten-
sifier. A wide range of guidewires, standard access cathe-
ters, angled tip catheters, stents of various lengths, and
diameter should be available. Stepped and tapered as well
as balloon dilators should also be available in case a tight
ureteric obstruction requires dilation before stenting.
Patient position
The patient is usually kept in a tilted supine position with
the ipsilateral flank slightly raised. Bolsters containing
radiopaque materials should be avoided. The operating
table should have the facility of a side tilt as the patient
may need to be brought into a supine position during the
procedure. This is often necessary in patients with ileal
conduits as access to the stoma can be difficult. The
patient should be in a lithotomy position if a combined
procedure (rendezvous) is planned.
Analgesia and sedation
Patient monitoring is essential before sedating the patient.
The task of monitoring vital signs should be delegated to
a specific member of the team. Suitable sedation is given
along with a prophylactic antibiotic. The choice of
sedative is determined by local protocol, the experience
of the operator in handling these medications combined
with patient factors. Intravenous midazolam is a suitable
agent that can be used in titrated doses. A general
anesthetic is preferred for the rendezvous procedure.
Technique
An antegrade study is performed via the nephrostomy
tube (Figure 17.1). This helps to get the surgeon oriented
to the anatomy of the renal pelvis, the location of the PUJ
in relation to the tip of the nephrostomy tube, and the
direction of the ureter. It also reveals the exact position of
the nephrostomy tube. The latter is usually performed by
another member of the team in an emergency setting and
therefore may not be placed in the most convenient loca-
tion. It is useful to make a note of the direction and length
of the tract of the nephrostomy tube as a tortuous and long
tract may cause buckling of the stent during insertion.
The nephrostomy tube is unlocked (Figure 17.2). It is
important to familiarize oneself with the locking and
unlocking mechanism of the tube as there are significant
variations between manufacturers. The guidewire will
not advance if the tube remains locked, nor will it be
possible to remove the nephrostomy tube.
A suitable guidewire is inserted into the renal pelvis
(Figure 17.3). A floppy tip wire with a moderately stiff
shaft is the best as it allows manipulations within the
pelvis. A straight tip 0.035 inch Zebra wire (Boston
Scientific, Natick, MA) is the personal preference of
the author. Terumo (Terumo Medical, Somerset, NJ),
ZIPwire and Sensor (both Boston Scientific) and Road-
runner (Cook Medical, Bloomington, IN) are suitable
alternatives.
CHAPTER 17 Step-by-Step Antegrade Ureteric Stenting 163
Getting the wire down the PUJ is the vital step of the
procedure. This can be difficult. Various tricks have been
described.
Several centimeters of the guidewire are inserted in
the renal pelvis. The nephrostomy tube is gently with-
drawn until it becomes straight. The tip of the guidewire
can be directed to the PUJ with the help of a rotating
movement of the nephrostomy tube. This can be difficult
in patients with a baggy renal pelvis. Nephrostomy sited
too medially (Figure 17.4) or in the lower calyx in a
patient with “high take-off ” of the ureter (high location
of the PUJ) are common scenarios which complicate
insertion of the wire into the ureter. The following varia-
tions can be tried.
Changing the guide ire to a slippery and hydrophilic
type is a useful first step. A Terumo or Zip-wire have a
floppy tip and are small enough to negotiate tight cor-
ners. These wires can be inserted and maneuvered with
ease but care needs to be exercised as they can fall out
easily with a resultant loss of access. Zebra, Sensor,
Amplatz or Road-runner wires can be used as alterna-
tives. All these wires are hydrophilic and must be kept
wet during the procedure to get the maximum benefit of
this feature.
Figure 17.1 Antegrade study.
Figure 17.2 Unlocking of the nephrostomy tube.
Figure 17.3 Successful insertion of guidewire.
Figure 17.4 Nephrostomy too medial.
164 SECTION 2 Large Renal Calculi (Percutaneous Nephrolithotomy)
Angled tip stiff catheters (Figures 17.5, 17.6) can be
used to direct the tip of the guidewire into the PUJ.
A Torcon Blue Biliary manipulating catheter (Cook
Medical, Bloomington, IN) (see Figure 17.5) is the personal
preference of the author. However, many other devices
are available that can serve the purpose. The catheter should
have adequate stiffness in the shaft. The length and the
angle of the tip are variable. Selection is made to suit the
anatomy of the PUJ. The devices used in vascular surgery
are often too long and unsuitable. Bending the tip of the
needle has been described to help achieve the same [12].
Once the PUJ is entered, the guidewire is advanced
down the ureter. The antegrade study performed while
commencing the procedure will guide the surgeon to get
the wire past the obstruction. It may be necessary to per-
form further imaging if the guidewire fails to advance. A
6 F ureteric catheter is passed over the wire to perform an
antegrade study. A long and tortuous ureter, tight
obstruction, deviation of the ureter due to extraluminal
compression, and extravasation of urine following trauma
are the usual obstacles that prevent successful advance of
the guidewire. Change to a smaller guidewire (such as
25 F) and the use of angled tip catheter are some alterna-
tives that may help to get past a difficult section of the
obstructed ureter.
The guidewire is advanced into the bladder. This can
be confirmed by inserting a 6 F ureteric catheter over the
wire and injecting of contrast.
A suitable stent is chosen. The diameter, stiffness, and
the length will be determined by the height of the patient
and the underlying pathology. It is essential to familiarize
oneself with the stent features as the radiopaque marker
positions vary from stent to stent. The stent is mounted
over the wire and is advanced into the renal pelvis. The
guidewire must remain straight and the tip should be
maintained in the bladder. Intermittent fluoroscopy
should be used to check the position of the wire to pre-
vent accidental withdrawal. It is vital to have an assistant
during the procedure.
A purpose-built variable-width stent (e.g. 7/14 F) with
its wide section sited at the PUJ is selected after the
endopyelotomy procedure.
Once the tip of the stent enters the bladder, a pusher is
used to advance it further till the marker is seen in the
bladder, thus ensuring that the curl has gone past the
ureteric orifice. The wire is withdrawn into the ureteric
stem of the stent and the distal coil is checked again.
A decision needs to be made about maintaining the
nephrostomy tube after a successful stent insertion before
the guidewire is removed completely. Drainage through a
JJ stent may not be adequate and retaining a nephrostomy
tube as a fail-safe back-up is a sensible option. It can be
clamped and removed when the stent has adequately
stabilized renal function.
A variation of technique should be used before removal
of the guidewire if a nephrostomy is to be reinserted. The
stent pusher is reinserted over the guidewire. The tip of
the pusher should be in contact with the tip of the renal
end of the JJ stent (Figure 17.7). This “joint” should be
positioned in the renal pelvis. This can be confirmed by
using fluoroscopy as the metal tip of the pusher can help
locate its tip. The guidewire is slowly withdrawn under
fluoroscopic control. The stent will curl away when the
wire leaves its lumen (Figure 17.8). The wire is now
advanced back into the renal pelvis and the pusher is
withdrawn. A fresh nephrostomy tube is inserted into the
Figure 17.5 Cook angled tip catheter.
Figure 17.6 Boston angled tip catheters.
CHAPTER 17 Step-by-Step Antegrade Ureteric Stenting 165
renal pelvis over the wire (Figure 17.9). The guidewire is
removed when the positions of the proximal end of the JJ
stent and the nephrostomy tube are confirmed to be
satisfactory (Figures 17.10, 17.11).
In conventional antegrade stenting, the guidewire is
removed under fluoroscopic control. It is essential to
ensure that the renal end of the JJ stent is curled in the
renal pelvis and not left in the tract as this may lead to a
urinary leak.
Rendezvous stenting
One of the pitfalls of antegrade stenting is the lack of
control of the distal end of the stent. There is a distinct
possibility of inadvertent failure to enter the bladder and
to leave the distal end of the JJ stent curled in the lower
end of the ureter. A cystoscopic confirmation is definitive
proof of correct stenting.
The other problem one may encounter is failure of
progression and inability to advance the guidewire past a
tight obstruction or a disrupted ureter due to severe trauma
(Figure 17.12) [13,14]. These problems can be overcome
by a combined procedure – the rendezvous technique. This
essentially involves two teams working simultaneously
to achieve successful passage of a guidewire from the
skin to the meatus or the stoma (Figure 17.13). The use of
a ureteroscope from below to help the team working
from the renal end has been shown to improve success.
It not only guides both the teams, but also irons out the
curvature of the ureter. Once the site of obstruction is
reached [15], a guidewire can be placed by either team.
This procedure is almost obligatory in patients with ileal
conduits, especially if the ureteroileal anastomosis has
been done with the Bricker technique as this makes retro-
grade access difficult.
Figure 17.7 JJ stent and pusher over wire.
Figure 17.8 JJ stent separating from the guidewire.
Figure 17.9 Nephrostomy reinserted.
166 SECTION 2 Large Renal Calculi (Percutaneous Nephrolithotomy)
Figure 17.10 Technique of retaining guidewire in pelvis after stent insertion.
Figure 17.11 Reinsertion of nephrostomy.Figure 17.12 Ureteric injury: retrograde study demonstrates traumatized ureter with extravasation.
CHAPTER 17 Step-by-Step Antegrade Ureteric Stenting 167
Special situations
Renal anomalies and solitary kidneyRenal anomalies such as duplex, ectopic, horseshoe and
pelvic kidneys need special consideration due to the
variations in the anatomy. It is advisable to reinsert the
nephrostomy tube after stenting when the patient has a
solitary functioning kidney.
Invasion of ureteric orificeInvolvement of the ureteric orifice due to pelvic
malignancy may be impossible to negotiate during
antegrade stenting. It may be prudent to consider a
rendezvous type of procedure in such patients. A
guidewire can be advanced down to the bladder in an
antegrade fashion. Cystoscopic resection of the tumor
invading the ureteric orifice is guided by the position of
the guidewire tip located with fluoroscopy. The guidewire
is retrieved after careful resection and the stent inserted
in a conventional manner.
Ureteric injuriesPatients with ureteric trauma and subsequent extrava-
sation of urine (see Figure 17.12) can be difficult as the
guidewire has a tendency to enter the traumatized wall
of the ureter. This can be more difficult if the separation of
the two ends of the traumatized ureter is significant or the
entire circumference of the ureter has been damaged.
The use of two ureteroscopes from either end aided by
cautious use of methylene blue can help to overcome this
problem. The nephrostomy tract is dilated to a size large
enough to accommodate a fiberoptic ureteroscope. The
latter is advanced to the superior end of the tear.
A semi-rigid or a fiberoptic ureteroscope is inserted from
below, intending to “rendezvous” and get a guidewire past
the traumatized segment. Successful stent insertion may
resolve the problem (Figure 17.14).
Ileal conduitsUreteric strictures in patients with ileal conduits can be
difficult to manage. The left ureter is more commonly
affected. Ischemia due to its long and tortuous route
behind the rectosigmoid results in this complication.
These strictures can also be caused by recurrence of
the underlying malignancy or late development of
ureteric tumors.
Stenting of a stenosed ureter in this group of patients
needs full evaluation of the conduit as well as upper
tracts. Cross-sectional imaging with a CT scan, a contrast
study through the ileal conduit (a loopogram) as well as
renography are essential. Insertion of a nephrostomy tube
in the obstructed kidney followed by an antegrade study
will also help to plan the procedure. Knowledge of the
type of ureteroileal anastomosis (Wallace or Bricker) is
important.
Figure 17.13 Placement of a through-and-through guidewire.
Figure 17.14 IVU after removal of JJ stent in the same patient.
168 SECTION 2 Large Renal Calculi (Percutaneous Nephrolithotomy)
The guidewire should be introduced from above through
the nephrostomy. It should be guided down the ureter after
imaging the upper tract as dilated ureters are often tortuous
and the bends can be difficult to negotiate (Figures 17.15,
17.16). The use of fiberoptic scopes from below via the ileal
conduit is advisable as this would aid retrieval of the
guidewire (Figures 17.17, 17.18, 17.19). Single J ( cystectomy
stent) stents should be used in preference to double J. The
caudal end of a double J stent will remain inside the conduit
which will be inaccessible for future stent changes.
A cystectomy stent can easily be changed by inserting a
guidewire up its lumen (Figure 17.20).
Other conditionsInsertion of a stent during pyeloplasty can be performed
in either a retrograde or antegrade manner. The selection
of the technique depends largely on the experience of the
surgeon, especially if a laparoscopic approach is used [16].
Figure 17.17 Advancement of guidewire.
Figure 17.18 Rendezvous with a flexible endoscope.
Figure 17.15 Pyelogram to help insertion of guidewire.
Figure 17.16 Advancement of ureteric catheter down the ureter.
CHAPTER 17 Step-by-Step Antegrade Ureteric Stenting 169
Chronic inflammatory processes of the ureter such as
tuberculosis result in multiple strictures at various levels
of the ureter. Balloon dilation followed by a stent is
preferable to open correction. A combined approach may
be necessary in patients with tight stenoses [17,18].
Pitfalls and dangers
It is important to be aware of the complications of this
technique. It is possible for the guidewire to perforate the
wall of the ureter. The stent will follow the wire and
remain outside the lumen. This complication can occur
at any level and may be missed. It is more likely to
develop in the lower third of the ureter (Figures 17.21,
17.22, 17.23, 17.24).
Exchange of guidewires and access catheters is
necessary in complicated ureteric strictures. The risk of
accidental loss of access due to inadvertent withdrawal of
the nephrostomy can be salvaged if the guidewire is
maintained in the system. The slippery guidewires can
accidentally fall out and therefore must be secured during
maneuvers. It is advisable to use a 10 F dual-lumen cathe-
ter (Figure 17.25) and insert a second wire to prevent this
accident if the procedure is difficult.
Removal of the nephrostomy tube from the renal pelvis
after a stent insertion needs attention. The coil of the
nephrostomy tube and the upper turn of the JJ stent can
get entangled. Inadvertent upward migration of the JJ
stent can easily occur (Figure 17.26).
Figure 17.19 Retrieval of the guidewire with a fiberoptic endoscope.
Figure 17.20 Two single J stents inserted in an ileal conduit.
Figure 17.21 Antegrade pyelogram.
170 SECTION 2 Large Renal Calculi (Percutaneous Nephrolithotomy)
Conclusion
Antegrade stenting of an obstructed ureter can be a
technical challenge due to many factors. Success can be
improved with careful planning, use of appropriate
guidewires and access catheters. Alternative plans need to
be considered in the event of obstacles encountered during
the procedure. Complex clinical scenarios should be
anticipated. Consideration should be given to a combined
(rendezvous) procedure under general anesthetic to
improve success, especially in bilateral ureteric obstruction.
The debate about who should undertake this procedure
continues. Many centers expect their radiology colleagues
to undertake the antegrade stenting while urologists
Figure 17.22 Incorrectly placed JJ stent – distal end in vagina.
Figure 17.23 Incorrect antegrade placement of a JJ stent in the vagina. Retrograde catheter in the distal ureter.
Figure 17.24 Both stents in correct positions.
CHAPTER 17 Step-by-Step Antegrade Ureteric Stenting 171
Figure 17.26 Accidental locking of the nephrostomy tube and the JJ stent during removal.
restrict themselves to the retrograde procedure. The
rendezvous procedure needs two teams with skills to
perform steps necessary from either end – perhaps a
urologist and a radiologist.
It is helpful for urologists to become familiar with the
technique of antegrade stenting as it is a natural extension
of the established retrograde technique. Ability to under-
take antegrade or rendezvous stenting gives the surgeon
the flexibility of switching over to these techniques if
conventional retrograde procedure proves difficult.
AcknowledgmentsThe author wishes to thank Boston Scientific and Cook
for their permission to use the images of devices and
Dr Elizabeth Bellamy for her artwork and help.
References
1 Uthappa MC, Cowan NC. Retrograde or antegrade double-
pigtail stent placement for malignant ureter obstruction?
Clin Radiol 2005;60(5):608–12.
2 Elyaderani MK, Belis JA, Kandzari SJ, Gabriele OF.
Facilitation of difficult percutaneous ureteral stent insertion.
J Urol 1982;128(6):1173–6.
3 Lu DS, Papanicolaou N, Girard M, Lee MJ, Yoder IC.
Percutaneous internal ureteral stent placement: review of
technical issues and solutions in 50 consecutive cases. Clin
Radiol 1994;49(4):256–61.
4 Liatsikos EN, Karnabatidis D, Katsanos K, et al. Ureteral
injuries during gynaecological surgery: treatment with a
minimally invasive approach. J Endourol 2006;20(12):1062–7.
5 Toporoff B, Sclafani S, Scalea T, et al. Percutaneous antegrade
ureteral stenting as an adjunct for treatment of complicated
ureteral injuries. J Truama 1992;32(4):534–8.
6 Ustunsoz B, Ugurel S, Duru NK, Ozgok Y, Ustunsoz A.
Percutaneous management of ureteral injuries that are
diagnosed later after cesarean section. Korean J Radiol
2008;9(4):348–53.
7 Postoak D, Simon JM, Monga M, Ferral H, Thomas R.
Combined percutaneous antegrade and cystoscopic
retrograde ureteral stent placement: an alternative tech-
nique in cases of ureteral discontinuity. Urology
1997;50(1):113–16.
8 De Baere T, Roche A, Lagrange C, et al. Combined percuta-
neous antegrade and cystoscopic retrograde approach in the
treatment of distal ureteric fistulae. Cardiovasc Intervent
Radiol 1995;19(6):349–52.
9 Jenkins CN, Marcus AJ. The value of antegrade stenting for
lower ureteric obstruction. J R Soc Med 1995;88(8):446–9.
10 Sharma SD, Persad RA, Haq A, et al. A review of antegrade
stenting in the management of obstructed kidney. Br J Urol
1996;78(4):511–15.
11 Chitale SV, Scott-Barrett S, Ho ET, Burgess NA. The
management of ureteric obstruction secondary to malignant
pelvic disease. Clin Radiol 2002;57(12):1118–21.
Figure 17.25 Dual-lumen catheters.
172 SECTION 2 Large Renal Calculi (Percutaneous Nephrolithotomy)
12 Nagele U, Anastasiadis AG, Amend B, et al. Steerable
antegrade stenting: a new trick of the trade. Int Braz J Urol
2007;33(3):393–4.
13 Brandt AS, von Rundstedt FC, Lazica DA, Roth S. Ureteral
realignment with the rendezvous procedure in complex
ureteral injuries – aspects of technique and our experience.
Aktuelle Urol 2010;41(4):257–62.
14 Anderson H, Alyas F, Edwin PJ. Intra-urinoma rendezvous
during a transconduit approach to re-establish ureteric
integrity. Cardiovasc Intervent Radiol 2005;28(1):95–7.
15 Asch MR, Jaffer NM. Antegrade placement of a ureteric
stent by a pull-through technique. Can Assoc Radiol
J 1995;46(6):465–7.
16 Chandrasekharam VV. Is retrograde stenting more reliable
than antegrade stenting for pyeloplasty in infants and
children? Urology 2005;66(6):1301–4.
17 Kim SH, Yoon HK, Park JH, et al. Tuberculous stricture of
the urinary tract: antegrade balloon dilation and ureteral
stenting. Abdom Imaging 1993;18(2):186–90.
18 How JW. Benign ureteric strictures – management by
percutaneous interventional uro-radiological techniques.
Ann Acad Med Singapore 1993;22(5):670–4.
