Keywords
Pancreatobiliary (ERCP/PTCD) - Cholangioscopy - PTCD/PTCS - ERC topics
Introduction
Percutaneous transhepatic cholangioscopy (PTCS) can be considered in patients with previous failed endoscopic retrograde cholangiopancreatography (ERCP) or with surgically or pathologically altered biliary anatomy posing a contraindication to peroral cholangioscopy [1]. Examples of PTCS indications include biliary stricture management and bile duct stone removal in patients with Billroth II gastrectomy [2] or Roux-en-Y anastomosis [3]
[4], removal of inaccessible, intrahepatic or complex biliary stones > 1.5 cm [5]
[6], mapping biopsies to assess the longitudinal upstream spread of hilar cholangiocarcinoma to aid in determination of resectability [7], and delivery of palliative intraluminal brachytherapy [8]. Because the American Society for Gastroenterology Endoscopy reported infectious adverse event (AE) rates as high as 35% in patients who have percutaneous cholangioscopy [9], accurate efficacy and safety data are needed to weigh the risks and benefits of its use.
Traditional reusable cholangioscopes designed for intraoperative or percutaneous use have larger accessory channels to allow a broader array of accessory devices, two-way tip deflection, and shorter working length and distance to the target area to improve ability to torque the scope to allow four-quadrant visualization [9]. The first catheter-based, fiberoptic, peroral, single-operator cholangiopancreatoscopy system with an intended use through the working channel of a duodenoscope and with a transpapillary access was launched in 2006 [10]. A second-generation system with an improved digital image and four-way deflection capability, easier set-up (“plug and play”), a larger accessory channel, and greater suctioning capability was cleared by the US Food and Drug Administration (FDA) in 2015 [10]. The newest cholangiopancreatoscopy system from the same manufacturer is a similar disposable, single-use, sterile device using the same platform with approximately one-third the length of the original catheter, optimized for percutaneous or surgical use. The device was cleared by the FDA in 2020 [11], but minimal data on its applications have been published to date [12]
[13].
We conducted a case series with 30-day follow-up to test the efficacy and safety of a new single-use cholangiopancreatoscope in adult patients scheduled for PTCS or other cholangioscopic procedures (including cholecystoscopy) for a variety of indications.
Patients and methods
Study design
We conducted a prospective, multicenter, multinational case series of PTCS to evaluate and treat complex pancreaticobiliary disease in adult patients. All centers obtained approval from their respective local ethics committees or institutional review boards and all patients provided signed informed consent before the procedure.
Cholangioscope description
The cholangiopancreatoscopy system used in the study was the SpyGlass Discover Digital System, (Boston Scientific Corporation, Marlborough, Massachusetts, United States; [Fig. 1] and [Table 1]). The SpyGlass Discover system has a shorter working length than Spy DS or Spy DSII (65 cm versus 214 cm respectively), but all three of these devices have the same field of view (120 degrees in air), distal tip width (10.5 F/3.5 mm), working channel diameter/minimum accessory width (1.2 millimeters/3.6 F), and minimum angulation range (30 degrees with accessory devices working channel). The SpyGlass Discover Digital System is indicated for use in diagnostic and therapeutic applications during endoscopic procedures in the pancreaticobiliary system including the hepatic ducts in adult patients. Because this system was used for cholangioscopy only (not pancreatoscopy) in the current study, it is called a “cholangioscope” in this paper.
Fig. 1 SpyGlass Discover Digital System used in the current study.
Table 1 SpyGlass Discover Digital Catheter specifications.
|
Specification
|
Value
|
|
Direction of view
|
0 degrees (forward viewing)
|
|
Field of view
|
120 degrees in air
|
|
Distal tip width
|
10.5F (3.5 mm)
|
|
Maximum insertion portion width
|
10.8F (3.6 mm)
|
|
Working length
|
65 cm
|
|
Minimum accessory channel width
|
1.2 mm (3.6F)
|
|
Minimum angulation range
|
30 degrees with accessory device in working channel
|
Procedure steps
Percutaneous biliary procedures were performed under general anesthesia and antibiotic prophylaxis. Initially, percutaneous biliary access was obtained under fluoroscopy by the radiology or gastroenterology team, following local expertise. An internal-external 8.5 F drain was inserted with the creation of a mature biliocutaneous fistula, allowing advancement of the cholangioscope on a guidewire in the percutaneo-biliary tract in a second step. In some cases, the tract was dilated using a 9 to 10 F bougie to allow passage of the cholangioscope to the bile ducts. Under direct visual control, the clinical intent was delivered (biopsies under direct visual control, stone fragmentation using electrohydraulic lithotripsy (EHL)/laser, selective duct cannulation). Just after the procedure, an internal-external drain was left in place to allow biliary drainage and reduce potential septic complications. At the end of the sessions, the percutaneous biliary drain was removed.
Patient population
Eligible patients were adults aged ≥18 years scheduled for a percutaneous transhepatic or transcholecystic procedure per local standard of practice. Patients were excluded for age < 18 years, contraindication to cholangiopancreatoscopy, unresolved adverse event(s) associated with prior percutaneous pancreaticobiliary ductal access, or potentially vulnerable status including but not limited to pregnancy.
Study visits
Baseline screening
After a participant was enrolled in the study and prior to the index PTCS procedure, pertinent medical history and any relevant pre-procedure imaging was assessed. Data on any prior percutaneous pancreaticobiliary ductal access procedure(s) including but not limited to number of catheter exchanges, diameter of catheters and length of time between initial percutaneous procedure and final tract maturation, were collected.
Index procedure
Procedure detail was obtained from medical records or recorded, including but not limited to description of procedures conducted and any additional procedures required. The reason for adding use of the cholangioscope to the radiologic procedure was documented. Cholangioscopy images were collected to create an atlas that illustrates utility of PTCS procedures in study cases. In addition, an operator user acceptance and satisfaction rating of the study device compared with reusable scopes based on ability to complete the procedure was recorded relating to study device design attributes. Data on all accessory devices used with the cholangioscope were also collected.
Thirty-day follow-up after the index procedure
After the index procedure, participant course and complications (if applicable) were recorded and evaluated for relatedness to the PTCS procedure by the treating physician. Any reinterventions required for participant management associated with the clinical indication for the index procedure were identified in three follow-up reviews of the electronic medical record/charts: 24 to 72 hours, 7 days ± 2 days, and 30 days ± 3 days after the index PTCS procedure.
Primary efficacy endpoint
The primary efficacy endpoint was achievement of the clinical intent (e.g., stone removal, stricture management) of the index PTCS procedure within 30 days (± 3 days) after the procedure. The number of PTCS procedures required to achieve the clinical intent by the end of follow-up was also evaluated.
Secondary endpoints
Secondary endpoints included: 1) technical success, defined as the ability to advance the cholangioscope catheter to the target lesion or stone(s) and visualize the target; 2) procedure time, defined as the time between first insertion and last removal of the cholangioscope catheter during the index PTCS; 3) endoscopist rating of each of the following attributes when using the cholangioscope system compared with marketed reusable scopes: ability to complete the procedure, retroflex, selectively advance into targeted ducts, obtain targeted biopsies, grasp stones, guide lithotripsy, suction, irrigate, and advance accessories through scope channel; and image quality; and 4) serious AEs (SAEs) related to the study device, accessory devices used through the working channel of the cholangioscope or the cholangioscopy portion of the PTCS procedure(s).
Statistical analysis
Descriptive statistics included the mean, standard deviation (SD), and range for age, tabulated rates of study PTCS procedure completion, and AEs, and median ratings for overall satisfaction, PTCS maneuvers and performance. Statistical analyses were performed using SAS 9.4 software (SAS Institute Inc., Cary, North Carolina, United States).
Results
Baseline patient characteristics
The cohort had a mean age of 64.7 ± 15.9 years (range 20.0–92.0) and included 30 men (60.0%) ([Table 2]). Thirty-two patients had a history of prior surgeries, most commonly cholecystectomy (22.0%, 11/50), Roux-en-Y gastric bypass (16.0%, 8/50), or a Billroth II procedure (16.0%, 8/50). One patient had received a liver transplant and one had a past pancreaticoduodenectomy.
Table 2 Baseline characteristics of patients (N=50 patients).
|
Characteristic
|
Mean ± SD (n) (range) or % (n/N)
|
|
SD, standard deviation.
|
|
Age
|
64.7±15.9 (28.0–92.0)
|
|
Male
|
60.0% (30/50)
|
|
Previous surgeries (one or more per patient)
|
|
|
36.0% (18/50)
|
|
|
22.0% (11/50)
|
|
|
16.0% (8/50)
|
|
|
16.0% (8/50)
|
|
|
4.0% (2/50)
|
|
|
2.0% (1/50)
|
|
|
2.0% (1/50)
|
|
|
28.0% (14/50)
|
|
Prior cholecystostomy tube
|
30.0% (15/50)
|
Index procedure characteristics
The most common indication for the study procedure was biliary stone management (58.0%, 29/50), followed by (one or more of the following in each patient): biliary stricture management (26.0%, 13/50), diagnosis of indeterminate biliary stricture with tissue acquisition (18%, 9/50), and gallstone management (16.0%, 8/50). Additional specified indications included diagnosis of indeterminate biliary stricture without tissue acquisition (4.0%, 2/50), cholangitis (4.0%, 2/50), drainage of hepatic fluid collection (2.0%, 1/50), gallbladder stricture management (2.0%, 1/50), and diagnosis of indeterminate gallbladder stricture without biopsy (2.0%, 1/50).
The reasons reported for a percutaneous approach were (one or more of the following in each patient): ERCP anticipated to be technically challenging or impossible (38.0%, 19/50), previous unsuccessful ERCP (34.0%, 17/50), prior cholecystostomy tube (30.0%, 15/50), to identify a source of hemobilia (2.0%, 1/50), or to minimize risk of infection (2.0%, 1/50).
All 48 technically successful baseline PTCS procedures were performed in an inpatient setting. Thirty of the PTCS procedures (62.5% of 48) were performed by an interventional radiologist, and 18 (37.5% of 48) were performed by a gastroenterologist/endoscopist. A mean of 2.5 ± 3.8 drains (range 1.0–20.0) were placed per patient, most commonly on the right side (82.8%, 77/93 drains placed).
At the index procedure, the most common cholangioscope maneuvers were (one or more of the following in each patient): visualization of a biliary stricture or lesion (58.0%, 29/50), biopsy of biliary stricture or lesion (26.0%, 13/50), clearance of biliary stones/sludge with (26.0%, 13/50) or without (16.0%, 8/50) lithotripsy, selected biliary cannulation (14.0%, 7/50), or clearance of gallstones/sludge without lithotripsy (12.0%, 6/50). These and other maneuvers are listed in [Table 3].
Table 3 Cholangioscope maneuvers performed at index PTCS procedure (N=50 patients).
|
Cholangioscope maneuver
|
% (n/N)
|
|
PTCS, percutaneous transhepatic cholangioscopy.
|
|
Visualization of region of interest in biliary stricture or lesion
|
58.0% (29/50)
|
|
Biopsy of biliary stricture or lesion
|
26.0% (13/50)
|
|
Clearance of biliary stone(s)/sludge, with lithotripsy: mechanical, electrohydraulic or laser
|
26.0% (13/50)
|
|
Clearance of biliary stone(s)/sludge, without lithotripsy
|
16.0% (8/50)
|
|
Selective cannulation of a biliary duct
|
14.0% (7/50)
|
|
Clearance of gallstone(s)/sludge, without lithotripsy
|
12.0% (6/50)
|
|
Removal of foreign body in the bile duct
|
8.0% (4/50)
|
|
Advancement of guidewire into the duodenum/jejunum for rendezvous procedures
|
6.0% (3/50)
|
|
Visualization of region of interest in gallbladder stricture or lesion
|
4.0% (2/50)
|
|
Establishing bile duct continuity after ductal injury
|
4.0% (2/50)
|
|
Clearance of gallstone(s)/sludge, with lithotripsy: mechanical, electrohydraulic or laser
|
2.0% (1/50)
|
|
Clearance of occluded biliary stent
|
2.0% (1/50)
|
|
PTCS maneuvers-other
|
2.0% (1/50)
|
Primary efficacy endpoint: achievement of clinical intent of index PTCS procedure
Forty-four patients (88.0%) achieved the clinical intent by 30 days after the index PTCS, with one procedure required to achieve the clinical intent until the end of follow-up in all cases. For example, [Fig. 2] and [Video 1] show common bile duct stone clearance using the cholangioscope and EHL in altered anatomy.
Fig. 2 Successful biliary stone clearance. A 73-year-old patient with previous surgical
status of mini bypass presented with cholestasis. MRCP disclosed an enlarged common bile
duct filled with more than 10 supracentimetric polyhedric stones. a An endoscopic retrograde approach was excluded after endoscopic control of
the anatomy using a pediatric colonoscope. An EDGE approach was not feasible because of
gastric resection as the patient’s previous surgical status. b
Percutaneous access was obtained by the gastroenterology team under fluoroscopic
guidance, with internal-external drain placement. c,d, video
One week later, lithotripsy with electrohydraulic lithotripsy was performed using the
cholangioscope through the percutaneous tract, with a total of five fragmentation
sessions. e The drain was kept in place until cholecystectomy,
with some stone fragments needing to be extracted after the surgery, and the drain was
removed thereafter, with excellent clinical resolution.
Qualität:
Common bile duct stone clearance using the cholangioscope and electrohydraulic lithotripsy.Video 1
Secondary endpoints
Technical success and procedure time
Technical success was achieved in 48 patients (96.0%), with a mean procedure time of 37.6 minutes (SD, 25.1; range 5.0–125.0). Of the remaining two patients with technical failure, one was a 69-year-old man with an indeterminate biliary stricture in whom the index procedure failed because the target could not be visualized. This patient later had surgery. The second was a 46-year-old woman with post-cholecystectomy biliary stones in whom the initial procedure failed when the catheter could not be advanced to the target and the target could not be visualized. She subsequently had balloon dilation followed by laser lithotripsy through the SpyGlass Discover working channel.
Endoscopist ratings of device attributes
The mean endoscopist rating of overall ability of the cholangioscope to complete the
procedure as indicated was 9.2 (SD, 1.6; range 1.0–10.0), including 46 scores (92.0%) in
the 8 to 10 range ([Fig. 3]). For specific maneuvers, mean ratings ranged from 8.3 (81.8% of scores 8 to 10)
for suction ability and 8.3 (66.0% of scores 8 to 10) for image quality to 9.5 (100% of
scores 8 to 10) for ability to obtain targeted biopsies.
Fig. 3 Ratings of specific cholangioscope attributes or features.
Procedures in patients with prior cholecystostomy tubes
Fifteen patients (30.0%) reported a prior cholecystostomy tube at baseline. The reasons for cholangioscopy in these patients were (one or more of the following in each patient): visualization-guided clearance of biliary stones or gallstones (11), to aid in visualization of the region of interest in a biliary stricture or lesion (3), to aid in visualization of a foreign body (1), or to help identify the source of hemobilia during stone clearance (1). In all patients who had a preexisting cholecystostomy tube, the tube tract was utilized for cholangioscopy access. To facilitate percutaneous cholangioscopy, the existing tube was removed over a wire. A second safety wire was then placed to ensure secure access, over which a 12 F sheath was inserted into the gallbladder. Larger access sheaths were then utilized as needed for removal of larger stones. If access to the common bile duct was required, a guidewire was advanced down the cystic duct and into the common bile duct and the small bowel. Once wire access was established, the 12 F sheath could be advanced into the common bile duct, through which percutaneous cholangioscopy could be performed. All of these procedures were technically successful.
Adverse events related to cholangioscope or PTCS
One patient had one SAE related to the cholangioscope or PTCS index procedure ([Table 4]). The patient was an 85-year-old man scheduled for PTCS for biliary stone
management. He had successful visualization and biopsy of a biliary stricture, clearance of
biliary stones with lithotripsy, and removal of a foreign body from the bile duct. This
patient experienced severe aspiration during the index procedure and died 12 days later. Two
other SAEs were observed during the follow-up of another patient, and classified as possibly
related to the procedure, although very unlikely. This patient was a 57-year-old woman who
had diagnostic PTCS including biopsies of an indeterminate biliary stricture. She had a
portal vein embolization the day after, then she developed hemobilia the day after the
embolization (and 2 days after the index procedure), which was managed conservatively and
resolved 6 days later. She also developed sepsis due to presence of a perihepatic collection
14 days after the index procedure, but another procedure had been performed 5 days before, which
replaced the previously dislodged biliary drainage.
Table 4 Serious adverse events related to the cholangioscope or PTCS procedure (N = 50 cases).
|
|
Number of SAEs
|
Percent of patients (n/N)
|
|
PTCS, percutaneous transhepatic cholangioscopy.
|
|
Any serious adverse event
|
3
|
4.0% (2/50)
|
|
Fatal aspiration
|
1
|
2.0% (1/50)
|
|
Sepsis due to cholangitis
|
1
|
2.0% (1/50)
|
|
Hemobilia
|
1
|
2.0% (1/50)
|
Three other patients had nonserious AEs related to the device or index procedure. The first was a 69-year-old woman with prior cholangitis who received prophylactic piperacillin/tazobactam before PTCS for biliary drainage during EHL for gallstone removal. When she developed cholangitis on post-procedure day 1, her antibiotic was switched to imipenem and the cholangitis resolved on post-procedure day 5. The second patient was a 78-year-old male with duodenal stenosis who had PTCS during EHL for biliary stones without antibiotic prophylaxis as planned, developed cholangitis on post-procedure day 1, and was treated with piperacillin/tazobactam with resolution on post-procedure day 6. The third patient was a 78-year-old woman with a narrow and angulated post-cholecystectomy common bile duct stricture and upstream multiple bile duct stones. Via the percutaneous route, she had a balloon dilation and stone extraction by laser lithotripsy of stones at the index procedure. She was reported to have bacterial angiocholitis on post-procedure day 1, was treated with meropenem, and received repeat PTCS and drainage with resolution on post-procedure day 13. During study monitoring, the treating physicians for these patients reported that the AEs were nonserious because they did not cause a new hospitalization or prolonged hospitalization.
Discussion
In this case series of 50 patients, 88% achieved the planned clinical intent within 30 days after one PTCS procedure. One patient (2%) experienced a related SAE, which had a fatal outcome. Endoscopists reported high ratings for the functional ability of the cholangioscope.
Although PTCS is performed much less commonly than ERCP, it offers important advantages for some indications. For example, endoscopic visualization is considered the most accurate tool currently available to distinguish benign from malignant pancreatobiliary strictures [10]. Tamada et al. and Sato et al. documented the value of PTCS for mapping biopsies to determine longitudinal cancer extension along the bile duct [7]
[14]. Tamada mentions that collection of multiple biopsies from the circumference of the margin of the stenotic area can only be accomplished under direct vision using PTCS, whereas transpapillary or transhepatic fluoroscopically guided bile duct biopsies are inadequate for this purpose [7]. PTCS is a useful alternative therapy for intrahepatic stones and can be used as the primary treatment modality when a partial hepatectomy is not indicated, with recognition that severe biliary stricture or advanced biliary cirrhosis increases risk of stone recurrence [5]. It can also be used for percutaneous stone removal in patients who are not candidates for laparoscopic cholecystectomy [15].
The current exploratory study is informative regarding indications endoscopists select for PTCS and procedure outcomes for those indications. PTCS is notable because of the baseline severity of illness of the PTCS patient population. For example, a retrospective study examined PTCS efficacy and safety outcomes in 13 patients with a prior Roux-en-Y reconstruction who presented with abdominal pain (5), fever (6), jaundice and fever (1), or septic shock (1) [3]. Eight patients with bile duct stones in a single intrahepatic duct or in the common bile duct had successful stone removal; however, the authors acknowledged that complete stone removal with PTCS would be difficult in cases of bile duct stones along multiple intrahepatic bile ducts. The remaining five patients had a biliary stricture, with SpyBite biopsies confirming cholangiocarcinoma (2) or recurrent cholangiocarcinoma (3) [3]. Another small case series described four patients with biliary strictures in whom conventional ERCP was not possible and percutaneous brushings were either nondiagnostic or unsatisfactory; using PTCS visualization and biopsy, a diagnosis was achieved in all of these patients without complications [16]. These studies show that PTCS with biopsy can be influential in a patient population that is small but challenging, in some of whom conventional biliary access with ERCP failed.
PTCS is one of several endoscopic techniques that may be considered after failed ERCP in
select patient populations. Of note, balloon enteroscopy-assisted ERCP has a known safety
profile that supports its use in cases of altered anatomy [17], but notably, it is associated with a lower success rate than other advanced
techniques. EUS-guided (via hepaticogastrostomy or gastrogastric in case of Roux-en-Y gastric
bypass) access has been developed in expert centers with good quality results, despite the
potential high complication rates [18]
[19]
[20]. All these alternative techniques do not completely replace PTC access, which is a
complementary technique today, when faced with scenarios for which it is the best option to
easily and safely deliver the desired therapy/diagnosis. The choice between the different
modalities is a case-by-case discussion based on indication, anatomy, and intervention
purpose.
Our study had strengths and limitations. This was an early case series of percutaneous cholangioscopy, including data from 50 patients followed for 30 days. Consecutive patient recruitment was not possible because study participation depended on the availability of adequate endoscopic and imaging expertise. For this reason, the study population and their results may not be typical of all patients receiving PTCS. Regarding limitations, PTCS-guided biopsy was performed at endoscopist discretion; therefore, histopathology data are incomplete and we could not accurately estimate the diagnostic accuracy of PTCS.
Conclusions
In conclusion, for selected patients in whom ERCP has failed or retrograde access is
impossible, PTCS treatment was associated with high clinical intent and excellent technical
success rates in academic medical centers. Although the related SAE rate was low, one fatal
periprocedural aspiration event occurred. PTCS offers an important clinical management option
for selected patients with altered anatomy or in whom ERCP has failed, and it should be
reserved for highly trained endoscopists at centers with adequate procedure volume.
Data sharing
The data, analytic methods, and study materials for this study may be made available to other researchers in accordance with the Boston Scientific Data Sharing Policy (http://www.bostonscientific.com/en-US/data-sharing-requests.html).
