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486
a
R. Jain and S. H. Chandrashekhara
Fig. 39.1 Diagrammatic
representation of push-type
gastrostomy technique. (a)
Gastropexy using anchor
suture device. (b) Standard
Seldinger technique of
gaining access into the
stomach using needle-wire
combination. (c) Tract dilated
serially and balloon catheter
pushed through peel away
sheath and fastened to
stomach wall. (d) Final
position of gastrostomy tube
a
c
b
d
Fig. 39.2 Push-type gastrostomy technique. (a)
PEG set (b) Gastropexy using anchor suture
device. Standard Seldinger technique of gaining
access into the stomach using needle-wire
combination. (c and d) Tract dilated serially and
balloon catheter pushed through peel away sheath
and fastened to stomach wall
c
b
d
39 Non-vascular Inter ventions oftheGastrointestinal Tract
487
a
Fig. 39.3 Diagrammatic illustration of the pull-type gastrostomy technique. Stomach is inated with air using nasogastric tube and percutaneous puncture is done (a). Guidewire is snared out through mouth (b).
Over the guidewire, sheath inserted till the mouth and folded stiff
b
c
Amplatz wire introduced and attached with gastrostomy tube with a
square knot. Whole assembly pulled out from stomach end till the
mushroom end abuts the stomach wall tube xed and fastened with
external bolster (c)
Fig. 39.4 Push-type gastrostomy tube in position
39.3 Percutaneous Jejunostomy
39.3.1 Indications
Feeding jejunostomy is preferred over gastrostomy for
patients at high risk of aspiration. Percutaneous jejunostomy is considered if converting a gastrojejunostomy to a
jejunostomy is not feasible or has failed. Additionally,
direct percutaneous jejunostomy is indicated for replacing
a surgically placed jejunostomy tube that has dislodged
prematurely.
Fig. 39.5 Deation of the retention balloon and external dislodgement
of the gastrostomy catheter with all three T-fasteners intact and a
healthy stoma. Gastrostomy tube was reinserted over a stiff guidewire
under uoroscopy
39.3.2 Technique
Direct percutaneous jejunostomy can be performed using
either uoroscopic or CT guidance. The initial technique for
percutaneous jejunostomy was outlined by Hallisey and
Pollard in 1994. Their method involves identifying a jejunal
loop in the left upper quadrant by introducing air through a
nasogastric tube. A 17-gauge needle is then used to directly
puncture the distended loop under uoroscopic guidance.
After conrming the needle’s position with a contrast injection, a 0.035-inch hydrophilic guidewire and a 5F hydrophilic catheter are introduced. The jejunum is anchored to
488
R. Jain and S. H. Chandrashekhara
the anterior abdominal wall using Cope sutures or T-fasteners.
The tract is dilated, and a 14-French locking pigtail catheter
is placed.
Alternatively, ultrasound or CT guidance can be used for
jejunal catheter placement. These imaging techniques help
identify a secure path to a proximal jejunal loop while avoiding structures like the colon. It is important to ensure that
only one jejunal loop is traversed. At our institution, we prefer inserting a 0.018-inch wire into the jejunal loop after the
initial puncture with a 22-gauge needle. T-fasteners are then
placed under uoroscopic guidance, followed by tract dilation and tube placement.
39.3.3 Ecacy andSafety
The technical success rates for percutaneous jejunostomy
range from 60% to 100% [5]. These rates tend to improve
with the use of anchor techniques. While complications
are similar to those of percutaneous gastrostomy,
procedure- specic issues include injury to other sections
of the small bowel and, more critically, the colon. The latter is a serious complication that can be minimized with
CT guidance. Alternatively, percutaneous endoscopic
guidance can be employed, where the target bowel loop
and the abdominal wall are illuminated with light to aid in
visualization.
39.4 Percutaneous Cecostomy
When rst described in 1710, the procedure was typically
performed through open surgery. However, recent advancements have introduced laparoscopic methods. Percutaneous
cecostomy has emerged as an innovative alternative to traditional surgical techniques, similar to percutaneous gastrostomy. A key advantage of percutaneous cecostomy is that it
can be performed under local anesthesia and intravenous
sedoanalgesia.
39.4.1 Indications
Cecal dilation exceeding 10cm carries a signicant risk of
perforation, with associated mortality rates reaching up to
50%. Prompt and effective decompression is critical in such
scenarios. The primary indication for colonic decompression
is colonic pseudo-obstruction or Ogilvie’s syndrome. While
colonoscopic decompression is successful in about 70% of
cases, those who do not respond to this method may require
cecostomy. Other indications for cecostomy include cecal
dilation due to distal large bowel obstruction and cecal vol-
vulus. Before proceeding with percutaneous cecostomy, it is
essential to rule out bowel necrosis or perforation.
39.4.2 Technique
When obtaining access, the anterior transabdominal approach
is preferred over the extraperitoneal option due to its simplicity. T-fasteners play a crucial role in performing cecopexy, as
they secure the anterior cecal wall to the abdominal wall,
preventing leakage into the peritoneal cavity. A 14–16 F
gastrostomy catheter is then advanced into the cecum and
ascending colon. Following dilatation and placement through
a peel-away sheath, the catheter is positioned for gravityassisted drainage.
39.4.3 Post-procedure Care
Post-procedure, the catheter undergoes gravity drainage and
requires regular saline ushing to prevent blockage. Close
supervision is crucial to identify catheter malfunction and
complications like pericatheter leakage.
39.4.4 Results andComplications
Limited reports that are available in the literature indicate
high technical success in percutaneous cecostomy procedures, particularly in cases of Ogilvie’s syndrome.
Complications are infrequent but may include pericatheter leakage, septicemia, abdominal wall sepsis, and fecal
peritonitis. Diligent attention to detail, the use of
T-fasteners and careful catheter management can help
minimize these complications, making percutaneous
cecostomy an effective and relatively low-risk method for
cecal decompression.
39.5 Balloon Dilatation ofEsophageal
Stricture
Traditionally, bougienage has been used to dilate esophageal strictures, involving an instrument with a round or oval
tip to gradually expand the stricture and achieve the desired
lumen size. Modern techniques now often utilize endoscopic approaches with bougies that can be passed over a
guidewire. However, compared to balloon dilation, bougies
have a drawback: they apply signicant longitudinal shear
forces to both the stricture and the surrounding esophagus,
which can increase the risk of mucosal tears and perforation. In contrast, balloon dilation applies radial stretch
39 Non-vascular Inter ventions oftheGastrointestinal Tract
489
forces without longitudinal shear, thereby minimizing the
risk of mucosal damage and perforation [6].
39.5.1 Technique
A barium swallow study is conducted to assess the size and
location of the esophageal stricture. For balloon dilation, the
patient is positioned in the lateral decubitus position, and the
procedure is typically performed via a transoral route. To
reduce the gag reex, a topical anesthetic spray is applied. A
5 F angiographic catheter and hydrophilic guidewire are
advanced under uoroscopic guidance into the esophagus.
After injecting a small amount of contrast, the guidewire and
catheter are maneuvered through the stricture and into the
stomach. An exchange length stiff wire is then introduced,
and a balloon with a diameter of either 10 or 12mm is used
initially, depending on the stricture. The goal is to achieve a
20mm luminal diameter by starting with a smaller balloon
and gradually increasing the size based on patient tolerance.
The balloon is inated for 1–2 min until the waist
disappears.
Immediate post-dilatation esophagogram is typically
avoided, as it may still show a stricture similar to the predilatation state due to acute muscular spasm induced by
the procedure. If signicant pain occurs during the procedure, non-ionic contrast material is injected to check for
mucosal tear or perforation. Otherwise, an esophagogram
is performed 4–6h later. The expected technical success
rate is 90%–95%, with around 70% of patients remaining
asymptomatic for up to 2years following dilation. Some
researchers have investigated the use of retrievable metallic stents, which have hooks at the proximal end for easier
removal [7].
39.6 Esophageal Stenting forMalignant
Esophageal Strictures
Patients with malignant esophageal strictures frequently
present with advanced or metastatic disease. Palliative measures are primarily aimed at restoring oral feeding and
enhancing the patient’s quality of life. Historically, rigid
plastic endoprostheses were used, but these have proven difcult to insert and are associated with a high complication
rate, including esophageal perforation, tube dislodgment,
hemorrhage, pressure necrosis, and aspiration pneumonia.
Complications occur in about 36% of patients, and procedural mortality rates range from 2% to 16% [8]. Laser therapy, while effective for palliation, often requires frequent
sessions and incurs signicant costs.
Self-expanding metal stent insertion is an attractive alternative for palliation in esophageal carcinoma (Fig. 39.6).
The selection of an appropriate stent involves careful consideration of factors such as migration risk and stent coverage.
When choosing stents for benign esophageal strictures,
options include retrievable metallic stents (such as Song,
Choo, FerX-Ella) and Polyex plastic stents. For lesion
involving the upper esophagus, Polyex or Ultraex stents
are preferred as they are less stiff and cause less discomfort
as compared to conventional metallic stents [7].
39.6.1 Technique
As with esophageal stricture dilation, a barium swallow study
is conducted prior to the procedure to document the stricture’s location and length. Under intravenous sedation and
positioned in the lateral decubitus position, a 5F angiographic
catheter and hydrophilic guidewire are advanced into the
Fig. 39.6 Schematic diagram
of esophageal stenting. The
guidewire is passed across the
stricture (a), followed by
dilatation by balloon (b) and
stenting (c)
ab c
490
R. Jain and S. H. Chandrashekhara
esophagus. After applying a local anesthetic, the catheter is
maneuvered under uoroscopic guidance to just above the
stricture. Contrast injection is used to outline the stricture,
which is then crossed with the guidewire and catheter. The
hydrophilic wire is replaced with a super stiff wire, and the
stent is loaded onto this guidewire and inserted through the
stricture. The stent is positioned so that it extends into the
normal esophagus above and below the stricture. In cases of
tight strictures, pre-dilatation may be necessary before stent
placement. After releasing the stent, an esophagogram is performed the following day to evaluate the stent’s position and
dilation. Patients are initially advised to follow a liquid diet,
gradually transitioning to solid food after 1–2weeks.
39.6.2 Stenting ofGastroesophageal Junction
Strictures
Traditionally, uncovered stents were utilized at the gastroesophageal junction due to concerns about migration.
However, contemporary covered stents have ared ends that
prevent migration. The conical wall stent, known as
Flamingo, has demonstrated promise in addressing migration concerns [9]. In the course of the procedure, coiling the
super-stiff guidewire in the stomach and distending the stomach with air helps ensure accurate placement of the stent.
The length of the stent within the fundus is kept to a minimum to reduce the likelihood of migration. Stents equipped
with antireux valves, such as the Choo or Do stent, are
available for use at the gastroesophageal junction.
39.6.3 Malignant Tracheoesophageal Fistula Stenting
Tracheoesophageal stula may develop secondary to esophageal cancer eroding into the tracheal wall and it presents
with difculty in swallowing and aspiration. Without intervention, a majority of patients develop malnutrition or pulmonary infection within a month. Perforation of the
esophagus is also a potential complication observed in
approximately 4–6% of patients undergoing laser treatment
and 5–8% of those treated with plastic endoprostheses for
esophageal carcinoma [8].
Literature reports demonstrate the effectiveness of using
covered metallic endoprostheses for treating malignant stulas [10]. Success rates range from 90% to 100% in sealing
off the stula or perforation, highlighting the critical need to
position the covered segment of the stent directly over the
site of the defect [11]. Follow-up esophagograms are typically performed the next day. If leaks are detected, a second
stent may be placed with overlapping coverage. It is important to avoid placing a stent above the upper esophageal
sphincter due to potential pain during swallowing. When a
covered metal stent is needed in the trachea, consulting with
a respiratory physician is advisable.
39.6.4 Outcome ofEsophageal Stenting
The rst successful treatment of a malignant esophageal
stricture with a metal stent was reported in 1990 [12]. Since
then, numerous studies have explored the use of various
metallic stent designs, both covered and uncovered. The procedure is generally considered safe and can be effectively
performed under uoroscopic guidance alone, without the
need for endoscopic assistance.
Comparative studies indicate that plastic and metallic
stents provide similar reductions in dysphagia scores.
However, plastic stents are associated with signicantly
higher morbidity and mortality compared to their metallic
counterparts [13]. Additionally, when comparing palliation
with metallic stents to laser therapy, metallic endoprostheses generally offer superior relief of dysphagia. Laser therapy has been associated with perforation rates between 6%
and 9%, making it less favorable compared to metallic
stents [14].
39.6.5 Complications
Complications associated with esophageal metal stent placement include stent migration, tumor ingrowth, perforation,
food impaction, chest pain, and hemorrhage. Uncovered
metallic stents are linked to tumor ingrowth in up to 20–30%
of patients, though the use of covered metallic stents has
largely mitigated this issue.
Stent migration is more common with certain covered
stent designs, particularly those with a polyurethane cover on
the outside of the stent. Newer stent designs, featuring ared
proximal or distal ends, have reduced migration rates, but
literature reports variable rates of 10–30% depending on the
type of covered stent used.
Other complications include occasional food impaction,
which can be managed by advising patients to drink carbonated beverages after meals to help clear residual debris from
the stent. Transient chest pain related to stent deployment
has been reported and may sometimes require narcotic analgesia, although the exact cause is unclear. Tumor overgrowth
has been observed in up to 6.2% of patients and can often be
addressed by placing an additional metal stent.
Hemorrhage occurs in 3–8% of patients, with most cases
being mild and self-limiting. The source of hemorrhage is
sometimes unclear, and while some patients may receive
radiotherapy, the effect of this treatment on bleeding complications is still uncertain.
39 Non-vascular Inter ventions oftheGastrointestinal Tract
491
References
1. Currie BM, Getrajdman GI, Covey AM, Alago W, Erinjeri JP,
Maybody M, etal. Push versus pull gastrostomy in cancer patients:
a single center retrospective analysis of complications and technical
success rates. Diagn Interv Imaging. 2018;99(9):547–53.
2. Kumar M, Chahal A, Malla S, Bharti SG, Kumar S, Biswas A,
etal. Efcacy and safety of percutaneous radiological gastrostomy
(PRG) as a rescue measure for enteral feeding in patients with
advanced head, neck, and upper digestive malignancies. Indian J
Radiol Imaging. 2022;32(4):471–8.
3. Thornton FJ, Varghese JC, Haslam PJ, McGrath FP, Keeling F, Lee
MJ.Percutaneous gastrostomy in patients who fail or are unsuitable for endoscopic gastrostomy. Cardiovasc Intervent Radiol.
2000;23(4):279–84.
4. Hallisey MJ, Pollard JC.Direct percutaneous jejunostomy. J Vasc
Interv Radiol. 1994;5(4):625–32.
5. Davies RP, Kew J, West GP.Percutaneous Jejunostomy using CT
uoroscopy. Am J Roentgenol. 2001;176(3):808–10.
6. Weintraub JL, Eubig J. Balloon catheter dilatation of benign
esophageal strictures in children. J Vasc Interv Radiol.
2006;17(5):831–5.
7. Hindy P, Hong J, Lam-Tsai Y, Gress F.A comprehensive review of
esophageal stents. Gastroenterol Hepatol (N Y). 2012;8(8):526–34.
8. Parker CH, Peura DA.Palliative treatment of esophageal carcinoma
using esophageal dilation and prosthesis. Gastroenterol Clin N Am.
1991;20(4):717–29.
9. Siersema PD, Hop WC, van Blankenstein M, Dees J.A new design
metal stent (Flamingo stent) for palliation of malignant dysphagia: a prospective study. The Rotterdam Esophageal Tumor Study
Group. Gastrointest Endosc. 2000;51(2):139–45.
10. Covered metallic stent for the treatment of malignant esophageal
stula combined with stricture | BMC Gastroenterology | Full Text
[Internet]. [cited 2024 Feb 1]. Available from: https://bmcgastro-
enterol.biomedcentral.com/articles/10.1186/s12876- 020- 01398- 6
11. Vermeulen BD, Siersema PD. Esophageal stenting in clinical practice: an overview. Curr Treat Options Gastroenterol.
2018;16(2):260–73.
12. Domschke W, Foerster EC, Matek W, Rödl W.Self-expanding mesh
stent for esophageal cancer stenosis. Endoscopy. 1990;22(3):134–6.
13. Malignant esophageal stulas and perforations: management with
plastic-covered metallic endoprostheses - PubMed [Internet].
[cited 2024 Feb 1]. Available from: https://pubmed.ncbi.nlm.nih.
gov/9240548/
14. Saxon RR, Morrison KE, Lakin PC, Petersen BD, Barton RE,
Katon RM, etal. Malignant esophageal obstruction and esophagorespiratory stula: palliation with a polyethylene-covered Z-stent.
Radiology. 1997 Feb;202(2):349–54.
Non-vascular Interventions
oftheGenitourinary Tract
TejPal, RanjanKumarPatel, NeerajKumar,
andS.H.Chandrashekhara
40
Key Messages
1. To decompress an acutely infected calyceal system PCN
plays a vital role and it can become a life-saving procedure in cases of or by preventing development of urosepsis and acute kidney injury.
2. Numerous other procedures can be undertaken via percutaneous access of the kidney, like capturing stone/foreign
body, dilation or stenting of a ureteral stricture and
endopyelotomy.
3. Refractory severe coagulopathy is the strongest contraindication to PCN.
4. PCN is most commonly extended for nephroureteral and
ureteric stent placement in cases of obstruction.
5. Balloon dilation of the stricture is one of the viable treatment strategies for ureteral strictures.
6. Percutaneous antegrade ureteric stent placement is a very
useful and effective method to manage ureteral injuries
and obstructions due to numerous causes where the retrograde approach cannot be performed or failed.
7. Lower urinary tract stulas (non-vascular) are more commoner than ureteroarterial stula (UAF). If percutaneous
nephrostomy fails to heal the stula, ureteric occlusion
should be considered and Fogarty balloon catheter should
be used for ureteric occlusion.
8. In candidates unsuitable for surgical reconstruction proximal ureteric embolization can be an option for UAF
T. Pal (*)
Department of Radiology, National Cancer Institute, Jhajjar, All
India Institute of Medical Sciences, Delhi, India
R. K. Patel
Department of Radiodiagnosis, All India Institute of Medical
Sciences, Bhubaneswar, India
N. Kumar
Department of Cardiovascular Radiology and Endovascular
Interventions, All India Institute of Medical Sciences, Delhi, India
S. H. Chandrashekhara
Department of Radiodiagnosis and Interventional Radiology,
IRCH, All India Institute of Medical Sciences, Delhi, India
using a combination of coils, gelatin sponge and other
embolizing agents like detachable balloons, N-butyl cyanoacrylate (NBCA) and vascular plugs.
9. Ureteroarterial stula (UAF) may cause life-threatening
haemorrhage, and surgical repair is often challenging due to
prior surgery and associated inammation and therefore
endovascular approach is increasingly used to manage UAF.
40.1 Introduction
Obtaining access into the renal calyceal system is a very common and vital procedure to decompress the acutely obstructed
system secondary to multiple causes and also as a therapeutic
procedure to remove renal/ureteric calculi, for ureteric strictures-stenting as well dilatation and to capture foreign bodies.
40.2 Percutaneous Nephrostomy (PCN)
Percutaneous nephrostomy is a minimally invasive procedure
to gain access into the renal collecting system and positioning
of a suitable size catheter into the pelvicalyceal system. It is a
most common and time-honoured intervention done in
patients having urinary tract obstruction from any cause, for
diversion of urinary ow and many more indications [1–10].
It is also undertaken to obtain access for ureteral stent placement in various ureteric pathologies, for capture of renal/ureteric calculus through percutaneous route, to dilate ureteric
strictures and in endoscopic procedures. We can use uoroscopy, sonography or computed tomography (CT) to locate the
collecting system for initiation of the procedure.
40.2.1 Indications andContraindications
A. Indications:
1. Relief of supravesical urinary obstruction secondary
to benign and malignant cause.
© The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024
S. H. Chandrashekhara (ed.), Textbook of Interventional Radiology, https://doi.org/10.1007/978-981-97-9601-4_40
493
494
T. Pal et al.
(a) Stone.
(b) Stricture—intrinsic or extrinsic.
(c) Intraluminal contents—blood clots, fungal balls,
sequestered papillae.
(d) Tumour of cervix, bladder or any other pelvic
organ.
2. To provide urinary diversion in cases of.
(a) Urinary leak due to trauma or ureteral injury from
iatrogenic cause.
(b) Urinary stulas,
(c) Haemorrhagic cystitis.
3. In cases of endourologic intervention:
(a) Calculus retrieval.
(b) For dilatation/stenting of the ureteral stricture.
(c) Fulguration of tumour.
(d) To capture foreign body (e.g., broken or misposi-
tioned stent).
(e) For endopyelotomy.
(f) Medicines injection.
(g) For tissue sampling of a urothelial mass/lesion.
4. Diagnostic purpose.
(a) Antegrade pyelography.
(b) Ureteral perfusion (Whitaker test).
B. Absolute Contraindications.
As such there are no absolute contraindications, apart
from clinically unstable patients. We have to weigh carefully the risk-benet ratio for all interventional procedures, and the same holds true in this scenario too.
C. Relative Contraindications.
1. Refractory coagulopathy which is very severe and
bleeding diathesis (e.g., thrombocytopenia, liver or
multiorgan failure). Patients who are on oral anticoagulant therapy can reliably be taken for the procedure but only after addressing the deranged
coagulation prole with no associated risk of bleeding thereafter.
2. Uncontrolled hypertension is associated with an
increased risk of bleeding during and after the
procedure.
3. Hyperkalaemia—Patients who require sedation or
general anaesthesia can worsen if they already have
hyperkalaemia.
4. Patient who are terminally ill and if their life span is
too short then it can become a relative contraindication as the complication associated with the procedure further deteriorates the quality of life and
increases the morbidity.
5. Pregnancy, especially the rst trimester to avoid the
effects of ionizing radiation to the foetus.
For transplanted kidneys, the indications for percutaneous
nephrostomy mostly remain the same as in native kidneys
[11, 12].
40.2.2 Pre-requisites fortheProcedure
[13–22]
Centres where PCN is performed should be equipped with:
1. Good quality ultrasound machine with Doppler function
to avoid vascular puncture.
2. An optimal resolution at panel detector/image intensi-
er having adequate collimation and shielding so that it
can help in performing precise needle placement under
uoroscopic guidance re.
3. Good quality CT machine is required in complex anat-
omy or difcult access cases to prevent injury of vital
organs.
4. As sedation may be required in some cases, well-trained
anaesthesia team and work station to monitor vital signs
of the patients before, during and after the procedure with
other devices, such as respirators, i/v pumps, and O2
supply.
Non-availability of good quality machines and skilled
operators leads to high rates of complication and procedure
failure.
40.2.3 Relevant Anatomy totheProcedure
andPre-procedural Planning
Understanding the anatomy of the renal collecting system
and its vascular supply is important for performing successful and non-complicated procedures. Main renal artery
divides into anterior and posterior divisions and their segmental branches supply the anterior two-thirds and posterior
one-third of the renal parenchyma. There is a relatively avascular plane between this anterior two-thirds and posterior
one-third parenchyma which is known as the Brodel line or
zone of relative avascularity. This zone of relative avascularity lies just posterior to the lateral convex margin of the kidney [23, 24].
One should also review the cross-sectional images prior
to the procedure to know the gross anatomy of the organ and
any associated anomalies like malrotation, malposition, collecting system variations, or any other pathology of the kidney including calculus, tumour, cystic lesions, etc. It is also
helpful in assessing the path from the skin surface up to the
collecting system as it may be challenging in some types of
body habitus and obese patients. Cross-sectional images also
help in delineating the relations of adjacent organs, particularly colon, lung, liver, and spleen.
Before starting the procedure, we must check the laboratory parameters to avoid bleeding and/or systemic complications like cardiac arrhythmias due to electrolyte imbalance
during or after the procedure. These may be institutional
40 Non-vascular Interventions oftheGenitourinary Tract
495
specic but generally include PT, INR, platelet counts and
serum electrolytes for hyperkalaemia (INR should be <1.5
and platelet count >50,000). Coagulopathy must be corrected before the percutaneous intervention. There is a separate chapter for protocols to be followed before doing
non-vascular interventions in cases of coagulopathy.
In routine cases, 8 Fr. catheter is deployed to drain the
calyceal system; however, in infected obstructed system like
pyonephrosis and in cases where frank blood or clots are suspected, we can upsize the catheter to 10-Fr. or 12-Fr to adequately drain the system with less chance of the catheter
occlusion.
All patients should be well explained regarding the indication of the procedure, associated potential complications
and nal outcome in the simplest language possible and written consent must be obtained before commencing the intervention [25].
40.2.4 Procedure Technique (Fig.40.1)
Fluoroscopic and US guidance are the generally used modalities for routine percutaneous nephrostomy; however, CT or
MR guidance can also be used in complex or difcult anatomy. Placing the patient in the prone position with a bolster
under the abdomen helps in xing the position of the kidneys
against the posterior abdominal wall and prevents their anterior displacement during the procedure. If the patient is not
comfortable in the prone position or some contraindication is
there like in pregnancy, lateral decubitus or prone oblique
position with the ipsilateral side facing upside can be made.
We inject local anaesthesia (1% lidocaine) at the chosen
skin site to minimize the pain during the procedure. Small
skin incisions can be made which facilitate the passage of
puncture needle, dilators and catheters through the dermis.
As we enter into the collecting system, withdraw the stylet of the coaxial puncture needle and with this clear urine
drains out. We inject small amount ~5–10ml of dilute contrast media (50% diluted iohexol) to opacity the PCS and
ureter which acts as a roadmap for the rest of the
intervention.
If the urine that comes out is turbid in appearance or frank
pus is there, then we can aspirate the pus to decompress the
system. In this scenario, inject minimal contrast volume and
that too slowly to avoid pyelovenous reux. In such cases we
can upscale the size of the draining catheter to 10F [26].
The next step is the introduction of preferably ‘J’ tip
hydrophilic 0.035-in. or 0.038-in. guidewire through coaxial
6 Fr. introducer under uoro guidance. Some radiologists
directly introduce stiff exchange guidewire, i.e., Amplatz, to
shorten the duration of the procedure but it can cause injury
to the collecting system if there is limited experience, especially when the hardware is of suboptimal quality.
Track dilatation is done using 6, 8 and 10F dilators over
the guidewire. It should be done strictly under uoro guidance because if we apply extra force during dilatation, we
can puncture the medial wall of renal pelvis/proximal ureter
if we are not restricting the distal tip of the dilator under the
connes of our roadmap.
Then we mount MPA and exchange the hydrophilic
guidewire with an extra stiff guidewire, i.e., Amplatz. MPA
was removed and we further dilated the tract using 8F dilator. As there is a bulk of paraspinal muscles in this region, we
can dilate the tract up to the renal capsule using 10F dilator
but not beyond that which allows easy deployment of the
drainage catheter.
a
Fig. 40.1 Percutaneous nephrostomy. The puncture of the calyx has to be done through the Brodel line or zone of relative avascularity (a). The
tip of the pigtail PCN catheter is in the renal pelvis (b and c)
b c
496
T. Pal et al.
After adequately dilating the tract, we nally mounted the
desired size pigtail catheter over the Amplatz guidewire.
Sometimes during deployment there is buckling of the catheter into the subcutaneous plane which prevents its progression toward the collecting system. In such conditions we can
use pigtail catheter along with its metallic straightener, but it
should be advanced till renal parenchyma only as it can easily
perforate the renal pelvis. Finally we place the distal part of
the catheter into the renal pelvis or proximal ureter. Pigtail is
reformed into the pelvis when we remove the stiff guidewire
which helps anchor the catheter into the collecting system.
Check nephrostogram is obtained to look at the position
of the catheter tip, for free passage of the contrast into the
pelvis/ureter and also to ensure that all holes of the catheter
are into the collecting system.
Urobag is connected to the hub of the catheter. Suturing is
done at the entry site to x the catheter with skin and bandages are applied over there.
40.2.5 Post-procedure Care
• Patients should be kept under observation for vital signs.
Post-procedure notes mentioning the steps of the proce-
dure and any complications during the procedure should
be conveyed to the referring doctor. If general anaesthe-
sia/moderate sedation was given before and intra-
procedurally, one must document the complete course till
one regains consciousness.
• Monitor the bag output for volume and its appearance by
the hospital staff at frequent intervals.
• Educating the patient to prevent tube dislodgement or
contamination and regular follow-up at coordinated inter-
vals is recommended.
40.2.6 Complications ofPercutaneous
Nephrostomy
A majority of the complications are very subtle and routinely
do not require any intervention. Haematuria after the procedure is observed in almost every patient, but if it is continued
beyond 24h, then it is a point of concern. Most of the time it
is a venous bleed and it only requires clamping of the urobad
tubing which produces a tamponade effect in the PCS and
stops the bleed. In rare instances when the source of bleed is
arterial, a CT angiogram is performed to look for any pseudoaneurysm formation or arteriovenous stula formation. It
can be addressed by percutaneous embolization procedure
and open surgery is never required. The mortality rate for
PCN is (0.046%–0.3%) which is very low [8, 27–29]. Other
complication is a systemic infection due to pyelovenous
reex when the system is infected as in pyonephrosis. Injury
to the colon can occur and chances are increased if some
unusual anatomy is there. Splenic injury, hydrothorax and
pneumothorax can also occur especially when upper pole
calyx is targeted for stone therapy.
40.3 Further Applications oftheBasic
Technique [30]
PCN is most commonly extended for nephroureteral and ureteric stent placement in cases of obstruction. If there is a
native bladder and long-term urinary drainage is required,
stent placement is a good option as they have been widely
used in the management of ureteral obstruction or ureteral
injury. Ureteral stents are generally placed by urologists
through a retrograde transvesical route via a cystoscope. But
when a retrograde approach is unsuitable like in complete
ureteral orice blockade by tumour within the bladder lumen,
percutaneous antegrade ureteral stenting is a safe and effective alternative technique. To assess whether the patient will
benet from the ureteral stent when nephroureterostomy is
in place, we can do a capping trial. If there is no increase in
the serum creatinine levels and no pericatheter leakage or
fever after capping for a few days, there are fair chances that
the ureteral stent will provide adequate drainage.
40.3.1 Nephroureteral Access
andPercutaneous Antegrade Ureteral
Stent Placement
• If PN is not in place, then it’s a two-stage procedure, i.e.,
percutaneous nephrostomy followed by ureteral stent
placement in an antegrade fashion. In patients who
already have nephrostomy catheter in situ, the second
stage of the procedure is directly performed.
• Both procedures are generally not performed in the same
sitting, and it is common to keep a gap of 7days after
placement of a nephrostomy tube before stent placement
to decrease the risk of stent lumen occlusion by blood clot
or any other debris. But it’s not a dictum, and the timing
of stent placement should be decided according to the
clinical scenario.
• If there is a nephrostomy in place, antegrade pyelography
is performed by injecting contrast material via the nephrostomy catheter, demonstrating complete ureteric segments and the ureterovesical junction and its various
pathologies like leakage, stricture or occlusion.
• After that we exchange nephrostomy catheter over the
straight-tip guidewire with 5F multipurpose diagnostic
angiographic vascular catheter (MPA). Once PUJ is
crossed and the ureter is accessed, then the catheter is
advanced and into the bladder over the wire.