Only few severe complications after endoscopic ultrasound guided drainage of pancreatic pseudocysts.
ABSTRACT Pancreatic pseudocysts arise as a complication to acute or chronic pancreatitis. Transmural drainage under guidance of endoscopic ultrasound (EUS) is a minimally invasive approach. The results of a case series was retrospectively reviewed with a mean follow-up of 441 days.
Twenty-two consecutive patients (mean age 51 years, 13 men) who had undergone EUS-guided drainage of pancreatic pseudocysts were included between December 2005 and August 2010. The mean cyst size was 8.1 cm. One or two 10 Fr. double pigtail stents were inserted into the pseudocyst from either the stomach or the duodenum.
Insertion of a stent failed in three of 22 patients. Two cases were discontinued due to technical difficulties. One procedure was converted to a surgical cystogastrostomy. In 19 patients, a stent was successfully inserted. Three developed symptomatic recurrences due to stent malfunction. One developed a pseudocyst that mechanically obstructed the common bile duct. One developed a malignant cyst. One had a surgical cystogastrostomy for reasons unrelated to the stent insertion. For 13 patients (59%), a single endoscopic treatment resulted in relief of symptoms and resolution of the pseudocysts. However, one of these subsequently developed an asymptomatic pseudocyst.
EUS-guided endoscopy has only few severe complications and long-term results are acceptable. Nevertheless, insertion can be technically challenging and stent-related complications may cause recurrence.
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ABSTRACT: In recent years, endoscopic ultrasonography (EUS)-guided techniques have been developed as alternatives to surgical, radiologic, or conventional endoscopic approaches for the treatment or palliation of several digestive diseases. The use of EUS guidance allows the therapeutic area to be targeting more precisely, with a possible clinical benefit and less morbidity. Nevertheless, the risks persist and must be taken into consideration. This review gives an overview of the complications observed with the most established procedures of therapeutic EUS. The PubMed and Embase databases were used to search English language articles on interventional EUS. The studies considered for inclusion were those reporting on complications of EUS-guided celiac plexus block (EUS-CPB), EUS-guided celiac plexus neurolysis (EUS-CPN), drainage of fluid pancreatic and pelvic collections, and EUS-guided biliary and pancreatic drainage (EUS-BD and EUS-PD). Variations in methodology and design in most studies made a thorough statistical analysis difficult. Instead, a frequency analysis of complications and a critical discussion were performed. Although EUS-guided celiac plexus injection causes mainly mild and transient complications, growing experience shows that EUS-CPN is not as benign a procedure as previously thought. Most of the major complications have been observed in patients with chronic pancreatitis. The findings show that EUS-guided drainage of fluid collections is a safe procedure. Complications occur more often after the drainage of pancreatic abscesses and necrosis. Although the heterogeneity of studies dealing with pancreatobiliary drainage makes the evaluation of risks after these procedures difficult, complications after EUS-BD and EUS-PD are relatively frequent and can be severe. The technical complexity and the lack of specifically designed devices may account for their complication rates. Clinicians can consider EUS-guided celiac injection and EUS-guided drainage of fluid collections to be safe alternatives to surgical and radiologic interventions. Well-designed prospective trials are needed to assess the risks of EUS-BD and EUS-PD accurately before they are broadly advocated after a failed endoscopic retrograde cholangiopancreatography (ERCP).Surgical Endoscopy 11/2013; · 3.43 Impact Factor
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ABSTRACT: The continued need to develop less invasive alternatives to surgical and radiologic interventions has driven the development of endoscopic ultrasound (EUS)-guided treatments. These include EUS-guided drainage of pancreatic fluid collections, EUS-guided necrosectomy, EUS-guided cholangiography and biliary drainage, EUS-guided pancreatography and pancreatic duct drainage, EUS-guided gallbladder drainage, EUS-guided drainage of abdominal and pelvic fluid collections, EUS-guided celiac plexus block and celiac plexus neurolysis, EUS-guided pancreatic cyst ablation, EUS-guided vascular interventions, EUS-guided delivery of antitumoral agents and EUS-guided fiducial placement and brachytherapy. However these procedures are technically challenging and require expertise in both EUS and interventional endoscopy, such as endoscopic retrograde cholangiopancreatography and gastrointestinal stenting. We undertook a systematic review to record the entire body of literature accumulated over the past 2 decades on EUS-guided interventions with the objective of performing a critical appraisal of published articles, based on the classification of studies according to levels of evidence, in order to assess the scientific progress made in this field.World journal of gastroenterology : WJG. 07/2014; 20(26):8424-8448.
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DANISH MEDICAL JOURNAL ?
INTRODUCTION: Pancreatic pseudocysts arise as a complica-
tion to acute or chronic pancreatitis. Transmural drainage
under guidance of endoscopic ultrasound (EUS) is a min-
imally invasive approach. The results of a case series was
retrospectively reviewed with a mean follow-up of 441
MATERIAL AND METHODS: Twenty-two consecutive patients
(mean age 51 years, 13 men) who had undergone EUS-
guided drainage of pancreatic pseudocysts were included
between December 2005 and August 2010. The mean cyst
size was 8.1 cm. One or two 10 Fr. double pigtail stents
were inserted into the pseudocyst from either the stomach
or the duodenum.
RESULTS: Insertion of a stent failed in three of 22 patients.
Two cases were discontinued due to technical difficulties. One
procedure was converted to a surgical cystogastrostomy.
In 19 patients, a stent was successfully inserted. Three de-
veloped symptomatic recurrences due to stent malfunction.
One developed a pseudocyst that mechanically obstructed
the common bile duct. One developed a malignant cyst.
One had a surgical cystogastrostomy for reasons unrelated
to the stent insertion. For 13 patients (59%), a single endo-
scopic treatment resulted in relief of symptoms and resolu-
tion of the pseudocysts. However, one of these subse-
quently developed an asymptomatic pseudocyst.
CONCLUSION: EUS-guided endoscopy has only few severe
complications and long-term results are acceptable. Never-
theless, insertion can be technically challenging and stent-
related complications may cause recurrence.
FUNDING: not relevant.
TRIAL REGISTRATION: not relevant.
A pancreatic pseudocyst (PPC) is a localized collection of
amylase-rich fluid situated within or adjacent to the pan-
creas enclosed by a non-epithelial wall. A PPC may devel-
op as a consequence of pancreatic inflammation or injury.
Most pseudocysts are asymptomatic and resolve
spontaneously. Treatment is required only in cases of
persisting PPCs causing symptoms such as abdominal
pain, infection or compression into the gastrointestinal
tract, pancreatic duct or the common bile duct.
Management of pancreatic pseudocysts has traditionally
been surgical open internal drainage. Open surgery, how-
ever, is associated with complications and mortality .
Endoscopic drainage is a minimally invasive alterna-
tive which may be performed by a trans-papillary or a
trans-mural approach. Drainage of the cyst fluid by the
trans-mural approach is achieved by inserting a stent be-
tween the pseudocyst and the gastric lumen (cystogas-
trostomy) or between the pseudocyst and the duodenal
lumen (cystoduodenostomy). The drainage procedure
may either be performed by endoscopy as a “semi-
blind” procedure, if an impression caused by the cyst is
present. Alternatively, it may be guided by endoscopic
ultrasonography (EUS). The latter method is believed to
be less risky since damage to interposed vessels can be
avoided during the creation of the fistula tract between
the cyst and the gut lumen.
The aim of the present retrospective study was to
evaluate the technical success and long-term clinical
outcome in patients with symptomatic PPCs treated by
EUS-guided transmural drainage.
MATERIAL AND METHODS
The inclusion period of this study covered the period
from December 2005 to August 2010. In this period,
Only few severe complications after endoscopic
ultrasound guided drainage of pancreatic pseudocysts
Ditlev Nytoft Rasmussen, Hassem Hassan & Peter Vilmann
Endoscopic Unit Z-806,
Dan Med J
A. Endoscopic ultrasound
image of a 10 cm pseudo-
cyst in the tail of the pan-
creas. Note the short dis-
tance between the
transducer and cyst.
B. Endoscopic ultrasound
image of two pseudocysts
with colour Doppler ex-
amination showing a sig-
nificant vessel separating
the two cysts. The corres-
ponding endoscopic pic-
ture in A is also seen in
the upper left corner.
? DANISH MEDICAL JOURNAL
Dan Med J ??/? April ????
EUS-guided transmural drainage of pseudocysts was
performed in 22 consecutive patients at Gentofte Hos-
pital. Demographic patient data are displayed in Table 1.
All patients suffered from symptomatic pseudo-
cysts. In 15 patients, percutaneous drainage had been
performed once prior to referral. In three additional
patients, percutaneous drainage had been performed
two or more times. In all of these 18 patients, the PPC
had recurred. Six of the patients had an infected PPC
on the day of endoscopic treatment. A PPC was evalu-
ated and reported by the endoscopist as being infected
based on observation of pus or sediment. Five patients
had more than one cyst. In these patients, only the
largest cyst was drained. The records did not facilitate
assessment of possible communications between
The sequence of individual procedural steps may be
delineated as follows:
– The ultrasound endoscope was advanced to the
stomach or the duodenum.
The PPC and the pancreas were assessed by EUS
and the location most suitable for the puncture was
selected. Doppler imaging was used to reduce the
risk of damaging interposed vessels.
– The cyst was punctured under EUS-guidance using a
19 G aspiration needle (Cook Medical).
A guidewire was advanced via the needle and
coiled-up inside the cyst monitored by EUS.
The needle was then retracted and removed from
A dilation catheter with a diameter of 8-10 mm or a
dilation balloon (TTS balloon, Boston Scientific) was
used to enlarge the cyst fistula. In some cases, it
was necessary due to a fibrous cyst wall to enter
the cyst using electrocauthery by means of a
One or two 10 Fr. straight stents or double pigtail
stents were subsequently inserted.
The functioning of the stent as well as the correct
position was confirmed by endoscopy and EUS.
Informed consent was obtained from every patient prior
to the procedure.
In order to evaluate the long-term results of the
drainage procedure, a post-procedure follow-up was
performed by reviewing the medical history of the pa-
tient following the procedure.
Trial registration: not relevant.
A total of 23 patients were referred for EUS-guided
drainage during the inclusion period. Twenty-two pa-
tients were found eligible for the procedure. One patient
was found ineligible for transmural drainage since the
pseudocyst was located too remotely as seen from the
stomach. In addition, vessels were interposed as seen
from the duodenum thereby preventing access. This pa-
tient was therefore not included in the present study.
Out of 22 patients in whom drainage was attempt-
ed, the average cyst diameter was 8.1 cm (3.8-18 cm)
measured by EUS.
In three patients (14%), the procedure was unsuc-
cessful. The sizes and locations of the cysts in these pa-
tients were 3.8 cm at the tail, 4 cm at the body and 8 cm
including the tail and body of the pancreas, respectively. In
one procedure, the pigtail stent was displaced into the cyst
and could not be retrieved. This procedure was subse-
quently converted to a surgical cystogastrostomy. In two
patients, the procedure was discontinued at an early stage
after EUS-guided needle insertion. In the first patient, it
proved impossible to bring the endoscope into a favoura-
ble position. In the second patient, the guidewire was dis-
placed several times. No attempt was made in these two
patients to enlarge the fistula tract or to insert a stent.
In one patient, the opening created between the
cyst and the stomach was found too large to support a
stent. A week later another endoscopist was, however,
Demographic data of patients scheduled for endoscopic ultrasound-
Age, mean (range), years 51 (23-73)
Aetiology of PPC, n (%)
Alcoholic pancreatitis 9 (41)
Gallstone 9 (41)
Idiopathic pancreatitis2 (9)
Traumatic pancreatitis 1 (5)
Pancreas divisum1 (5)
Health status, n (%)
ASA 1 7 (23)
ASA 213 (59)
ASA 32 (9)
Location of PPC, n (%)
Pancreatic head4 (18)
Pancreatic body6 (27)
Pancreatic tail6 (27)
Behind the stomach3 (14)
Adjacent to the liver1 (5)
Not reported2 (9)
Symptoms caused by the PPC, n (%)
Vomiting and abdominal pain4 (18)
Abdominal pain16 (82)
ASA = American Society of Anesthesiologists.
PPC = pancreatic pseudocyst.
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DANISH MEDICAL JOURNAL ?
able to successfully place two double pigtail stents via
Thus, insertion of a functioning stent was successful
in 19 of 22 patients (86%). Additional data are shown in
In one case a conscious sedation had to be con-
verted to general anaesthesia.
The outcome of the endoscopic treatment for the
19 patients (86%) with a functioning stent can be de-
scribed as follows:
The median follow-up was 230 days (range 85-1,547
days). During this period four patients (18%) developed
complications related to malfunctioning of the stent.
Stent clogging caused one patient (5%) to be hospital-
ized with epigastric pain, infection and recurrence of the
PPC. This case was managed with a nasocystic drain.
Stent migration caused two patients (9%) to devel-
op symptomatic recurrence of the PPC. In one case, the
migrated stent was replaced with a second stent under a
repeated EUS-guided procedure. This second stent suc-
cessfully drained the PPC and caused the symptoms to
disappear. In the other case, an attempt to replace the
migrated stent was unsuccessful.
In one patient (5%), the PPC became infected short-
ly after insertion. Meanwhile, the same patient was
scheduled for elective cholecystectomia 20 days after
the endoscopy. The patient was then informed about
two options for treatment of the infected pseudocyst.
These options were either a repeated endoscopic
proced ure or a surgical cystogastrostomy during the
elective laparoscopic cholecystectomy. The latter was
chosen as the final outcome.
During the follow-up period, one patient (5%) de-
veloped a PPC that mechanically obstructed the com-
mon bile duct. Nineteen days after the first stent inser-
tion, this case was managed by insertion of a stent in the
pancreatic duct using ERCP.
A single patient (5%) developed a new cyst in the
tail of the pancreas which was subsequently diagnosed
as malignant. The tumour was removed by radical exci-
Seven months after endoscopy, another patient
(5%) developed an asymptomatic persistent PPC with a
diameter of 8 cm, despite a stent. No further treatment
was performed in this case.
Twelve patients experienced relief of symptoms
and did not develop new pseudocysts or complications
due to the endoscopic procedure during the follow-up
period. Thus, a single endoscopic procedure was the cur-
ative treatment for 12 patients (55%). However, two of
these were admitted to hospital with abdominal pain
during the follow-up period. Examinations, nevertheless,
showed that their pain was not caused by a recurrent
PPC, but could be ascribed to exacerbation of chronic
If the case of asymptomatic recurrence is also re-
garded as a treatment succes, the number increased to
13 patients (59%).
Additional data on the inserted stents are shown in
In the present study, a single endoscopic procedure was
curative in 13/22 patients (59%) when the single case of
asymptomatic recurrence of PPC wasis regarded as a
treatment success. The analysis of data presented by
Azar et al in a study of 23 patients showed this figure to
be 61% . In another study of 51 patients, the figure
was 84% , and in a study of 11 patients  the figure
Data on the procedure in patients treated by endoscopic ultrasound-
Patients with a stent inserted, n19
Site of endoscopic puncture, n (%)
Duodenum 1 (5)
Both 1 (5)
Number of stents inserted, n procedures (%)
1 stent 6 (32)
2 stents13 (68)
Anaesthesia, n (%)
General anaesthesia10 (53)
Sedation with propofol 4 (21)
Midazolam analgesia 5 (26)
Antibiotic prophylaxis, n (%)
No antibiotics 5 (26)
Antibiotic prophylaxis 14 (74)
Setting, n (%)
Follow-up on the stents in patients treated by endoscopic ultrasound-
Stents in follow-up procedures, n (%)
Number of stents 19 (86)
Migrated, causing symptoms 2 (11)
Migrated, asymptomatic2 (11)
Status of stent not reported2 (11)
Patency period known, n (%)
Number of stents13 (67)
Clogged 1 (5)
Replaced by surgical cystogastrostomy1 (5)
Removed endoscopically as planned11 (58)
Patency for these, mean (range), days147 (85-354)
? DANISH MEDICAL JOURNAL
Dan Med J ??/? April ????
Table 4 lists the complications encountered in the
present study and their frequency in comparable
Other authors reported that conversion to surgery
had been required due to bleeding , pneumoperito-
neum [3, 5] and peritonitis . None of these complica-
tions occurred in the present study.
In the present study, no perforation occurred.
Other authors were less fortunate [10, 11].
No significant bleeding occurred in the present
study. This may be so owing to the use of Doppler imag-
ing to avoid interposed vessels in our study. Some
authors have, however, found standard ultrasonic imag-
ing without the use of Doppler to be adequate to secure
safe drainage of pseudocysts, even in patients at a high
risk of bleeding .
Returning to the one case (5%) of conversion from
conscious sedation to general anaesthesia in the present
study as reported above, a similar anaesthetic incident
was reported by Azar et al . These cases should not be
considered a complication to the endoscopic procedure.
In the latter case, the endoscopic procedure was can-
celled, while in the present study the endoscopist was
able to complete the procedure.
EUS-guided procedures have been reported to take
longer than conventional procedures . Another
author found that time could be saved if the transmural
drainage was performed as a single-step procedure as
was the case in the present study . A single step pro-
cedure was conducted with an EUS-endoscope as op-
posed to a multistep procedure in which an EUS-endo-
scope would have had to be exchanged by a therapeutic
Some authors have used fluoroscopic control to op-
timize access into the pseudocyst. This was not used in
the present study, and EUS-guided drainage has been ar-
gued to be efficient and safe without fluoroscopy .
In the present study, one or two stents with a diam-
eter of 10 Fr. were used. The insertion of two stents may
be more advantageous than one . It has been sug-
gested that a stent diameter of 10 Fr. may cause fewer
cloggings than a stent diameter of 7 Fr. . Ran-
domized studies are required to draw any firm conclu-
EUS-guided drainage was compared with conven-
tional endoscopic drainage in a prospective randomized
study  and a prospective non-randomized study .
These studies showed that the EUS-guided proced-
ure was advantageous when compared with the conven-
tional endoscopic procedure. The difference between
the two methods could be explained by conventional
endoscopy not being able to handle non-bulging PPCs.
The two methods were equally efficient for managing
PPCs that did show luminal bulging.
Two prospective, but non-randomized studies [13,
19] supported the use of EUS in selected patient popula-
tions. In the first study, EUS guided drainage was used for
patients not considered ameanable to a conventional pro-
cedure . These patients had either gastric varices, un-
controlled coagulopathy or pseudocysts that did not dis-
play bulging. The technical success rates for the selected
group treated with EUS-guided drainage and the group
treated with conventional endoscopy did not differ.
In the second study, EUS-guided drainage was used
only when conventional endoscopic drainage was unsuc-
cesful . All pseudocysts located in the tail of pan-
creas failed to be managed with a conventional endo-
scopic procedure, while EUS-guided drainage proved
The literature offers conflicting recommendations
as to the optimal time for stent retrieval, ranging from a
few weeks to no retrieval. Two major concerns are asso-
ciated with leaving a stent in situ for an extended period
of time, namely stent clogging and the risk of bacterial
colonization of the stent. On the other hand, some
authors believe that premature retrieval of a stent may
increase the risk of PPC recurrence. The effect of the pa-
tency period was evaluated in a randomized study .
In the first group of 15 patients, stent retrieval took
place after two months. In a second group of 13 pa-
tients, stent retrieval was scheduled for 12 months after
insertion. In five of the 15 patients whose stent was re-
moved after two months, a recurrence occurred,
whereas by contrast none of the 13 patients who had
their stent removed after 12 months experienced a re-
currence of their cyst. Stent clogging or infection related
to the stent was not reported in any of the 13 patients
with an extended drainage period.
EUS-guided drainage of PPCs is a technically challenging
Encountered complications and their frequency in comparable studies.
ComplicationIn present study Reference
Conversion to surgical cystogastrostomy
due to stent displacement into the PPC
1 of 22 1 of 36 
1 of 11 
Recurrence of the PPC due to stent
1 of 22 2 of 36 
3 of 24 
1 of 6 
1 of 3 
Symptomatic recurrence of PPC due to
stent migration into the gastrointestinal
2 of 22 4 of 36 
1 of 11 
1 of 3 
3 of 24 
Abdominal pain continues despite no
recurrence of the pseudocyst
2 of 22 1 of 14 
PPC = pancreatic pseudocyst.
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DANISH MEDICAL JOURNAL ?
procedure which is not successful in all cases. Despite
the present patient series being small and the study be-
ing retrospective, the data showed that the procedure
had only few severe complications. In those who suc-
ceeded, the functional long-term results were accep-
table. Immediate complications were stent dislodge-
ment and in the short term infections due to clogging.
CORRESPONDENCE: Ditlev Nytoft Rasmussen, O.V. Kjettinges Allé 8, 4. tv.,
2000 Frederiksberg, Denmark. E-mail: firstname.lastname@example.org
ACCEPTED: 11 January 2012
CONFLICTS OF INTEREST: none
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