Utility of endoscopic ultrasonography in endoscopic drainage of pancreatic pseudocysts in selected patients

Endoscopic ultrasound-guided treatments: are we getting evidence based--a systematic review

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.

Endoscopic ultrasound-guided drainage of pancreatic fluid collections

Pancreatic fluid collections (PFCs) develop secondary to either fluid leakage or liquefaction of pancreatic necrosis following acute pancreatitis, chronic pancreatitis, surgery or abdominal trauma. Pancreatic fluid collections include acute fluid collections, acute and chronic pancreatic pseudocysts, pancreatic abscesses and pancreatic necrosis. Before the introduction of linear endoscopic ultrasound (EUS) in the 1990s and the subsequent development of endoscopic ultrasound-guided drainage (EUS-GD) procedures, the available options for drainage in symptomatic PFCs included surgical drainage, percutaneous drainage using radiological guidance and conventional endoscopic transmural drainage. In recent years, it has gradually been recognized that, due to its lower morbidity rate compared to the surgical and percutaneous approaches, endoscopic treatment may be the preferred first-line approach for managing symptomatic PFCs. Endoscopic ultrasound-guided drainage has the following advantages, when compared to other alternatives such as surgical, percutaneous and non-EUS-guided endoscopic drainage. EUS-GD is less invasive than surgery and therefore does not require general anesthesia. The morbidity rate is lower, recovery is faster and the costs are lower. EUS-GD can avoid local complications related to percutaneous drainage. Because the endoscope is placed adjacent to the fluid collection, it can have direct access to the fluid cavity, unlike percutaneous drainage which traverses the abdominal wall. Complications such as bleeding, inadvertent puncture of adjacent viscera, secondary infection and prolonged periods of drainage with resultant pancreatico-cutaneous fistulae may be avoided. The only difference between EUS and non-EUS drainage is the initial step, namely, gaining access to the pancreatic fluid collection. All the subsequent steps are similar, i.e., insertion of guide-wires with fluoroscopic guidance, balloon dilatation of the cystogastrostomy and insertion of transmural stents or nasocystic catheters. With the introduction of the EUS-scope equipped with a large operative channel which permits drainage of the PFCs in “one step”, EUS-GD has been increasingly carried out in many tertiary care centers and has expanded the safety and efficacy of this modality, allowing access to and drainage of overly challenging fluid collections. However, the nature of the PFCs determines the outcome of this procedure. The technique and review of current literature regarding EUS-GD of PFCs will be discussed.

Efficacy of endoscopic ultrasound-guided drainage of pancreatic pseudocysts in a pediatric population

BACKGROUND

While pancreatitis is uncommon in children, pseudocyst development can be a serious complication. Endoscopic drainage of pseudocysts is well established in adults. However, there are limited data regarding this procedure in a pediatric population. The objective of this study is to determine the safety and efficacy of endoscopic ultrasound-guided pseudocyst drainage in children.

METHODS

The study group included children (age <18 years) who presented for endoscopic drainage of symptomatic pancreatic pseudocysts in whom endoscopic ultrasound (EUS) was performed. In those cases with EUS guidance, a 19-gauge needle was used to access the pseudocyst and place a guidewire under fluoroscopic visualization. Needle-knife diathermy and balloon dilation of the tract were performed with subsequent placement of double pig-tailed stents for drainage.

RESULTS

Ten children with mean age of 11.8 years (range 4-17 years) were analyzed for pancreatic pseudocysts due to biliary pancreatitis (n = 4), trauma (n = 2), familial pancreatitis (n = 1), idiopathic pancreatitis (n = 2), and pancreas divisum (n = 1). In eight cases, EUS-guided puncture and stent placement was successful. In the remaining two cases, aspiration of cyst fluid until complete collapse was adequate. As experience increased with EUS examination in children, the therapeutic EUS scope alone was used in 50% of cases for the entire procedure. In all ten cases, successful transgastric endoscopic drainage of pseudocysts was achieved.

CONCLUSIONS

Endoscopic drainage of symptomatic pancreatic pseudocysts can be achieved safely in children. EUS guidance facilitates optimal site of puncture as well as placement of transmural stents.

Single-Step EUS-Guided Transmural Drainage of Pancreatic Pseudocysts: Analysis of Technical Feasibility, Efficacy, and Safety

BACKGROUND/AIMS

With the progress of product development, single-step endoscopic ultrasound (EUS)-guided transmural drainage can overcome some disadvantages of the blind or two-step procedures used in the treatment of pancreatic pseudocysts. We therefore evaluated the technical feasibility, efficacy, and safety of single-step EUS-guided transmural drainage of pancreatic pseudocysts.

METHODS

Endoscopic drainage of pancreatic pseudocysts was performed in 47 patients (median age, 46 years; range, 38 years to 59 years; 40 men) by using interventional echoendoscopes with a single-step device suitable for ballooning, bougination, and plastic-stent insertion.

RESULTS

Endoscopic stent placement was successful in 42 patients (89%; transgastric approach, 34/38; transduodenal approach, 8/9) and failed in 5 patients because of acute angulation (n=4) or small cyst (n=1). The volume of the pseudocyst was reduced by more than 90% or it disappeared completely in all of 41 patients (100%), based on a mean follow-up period of 17 months (range, 11 months to 20 months). The overall recurrence rate was 12% (5/41) after improvement by the procedure. Minor complications (one case of bleeding, three cases of pneumoperitoneum, and one case of peritonitis) occurred after the procedure in five patients (11%), but there were no major complications.

CONCLUSIONS

Single-step EUS-guided transmural drainage can be used to treat pancreatic pseudocysts with acceptable feasibility, efficacy, and safety.

EUS-guided transesophageal, transgastric, and transcolonic drainage of intra-abdominal fluid collections and abscesses

BACKGROUND

The therapeutic role of EUS is evolving. We report our experience with EUS-guided transesophageal, transgastric, and transcolonic drainage of various intra-abdominal fluid collections.

OBJECTIVE

To determine the technical feasibility and clinical outcomes of EUS-guided drainage.

DESIGN

Prospective case series.

SETTING

Academic tertiary referral center.

PATIENTS

Patients referred for endoscopic drainage of intra-abdominal fluid collections; pancreatic pseudocysts amenable to conventional transgastric or transduodenal drainage were excluded.

INTERVENTIONS

Single-step EUS-guided drainage of fluid collections by using a therapeutic linear-array echoendoscope with fluoroscopic guidance.

MAIN OUTCOME MEASUREMENTS

Technical success, relief of symptoms, and procedural complications.

RESULTS

Nine consecutive patients deemed appropriate for EUS-guided drainage of intra-abdominal fluid collections included transesophageal drainage of pseudocysts (n = 2), transgastric drainage of biloma (n = 2) and upper intra-abdominal abscesses (n = 2), transcolonic drainage of diverticular abscess (n = 1), Crohn's abscess (n = 1), and postoperative hematoma (n = 1). Endoscopic drainage was successful in all patients. Confirmation of complete resolution of the target fluid collection and symptom relief was achieved in 8 (89%) of 9 patients. Pneumothorax and mediastinitis developed in 1 patient after transesophageal drainage, which resolved with chest tube and medical therapy. During multiple stent placement, one of the stents was fully deployed into the abscess cavity in 2 patients; both were successfully retrieved either endoscopically (Crohn's abscess) or at the time of primary colonic resection (diverticular abscess).

LIMITATION

Limited number of patients.

CONCLUSIONS

EUS-guided transenteric drainage of bilomas, hematomas, abscesses, and inflammatory fluid collections is technically feasible and generally results in complete drainage and symptom relief. Procedural complications may be minimized with more experience.

Cystic lesions and intraductal neoplasms of the pancreas

Pancreatic cystic lesions are being detected more frequently given increased use of cross-sectional imaging modalities. The most common cysts encountered are mucinous cysts, which have malignant potential. As many of these lesions are incidental findings, it is important to further evaluate them with endoscopic ultrasound-guided fine needle aspiration for diagnostic purposes and risk stratification. These cysts either require surgical resection or surveillance given the malignant risk. Mucinous cystic neoplasms should be resected. Intraductal papillary mucinous neoplasia (IPMN) has consensus-guideline indications for resection. These include main duct diameter > or = 10 mm, a branch duct size > or = 3 cm, presence of a mural nodule, or cytology suspicious for malignancy. Additionally, all symptomatic cysts, regardless of etiology, should undergo resection. Branch duct IPMN is less aggressive that the main duct variety, and may be conservatively followed. However, the development of an established indication for resection should prompt surgery. Despite generalized guidelines, decisions regarding management of pancreatic cysts should be individualized, accounting for the malignant risk of the lesion and the surgical risk of the patient.

Role of EUS in drainage of peripancreatic fluid collections not amenable for endoscopic transmural drainage

BACKGROUND

Increasingly, peripancreatic fluid collections (PFCs) are managed endoscopically with conventional transmural drainage (CTD). The role of interventional EUS in drainage of PFCs requires further clarification, because the procedure is technically challenging, with limited availability.

OBJECTIVE

Identify characteristics that determine the need for drainage of PFC by CTD versus EUS.

PATIENTS

Consecutive patients with symptomatic PFCs (types: pseudocyst, abscess, and necrosis) referred for endoscopic drainage.

STUDY DESIGN

Prospective study.

SETTING

Tertiary-referral center.

METHODS

After ERCP, transmural drainage was attempted by CTD. If unsuccessful, drainage by EUS was then attempted. Findings on contrast-enhanced CT and endoscopy were collected to identify characteristics that predict the need for CTD versus EUS drainage.

MAIN OUTCOME MEASUREMENTS

Identify characteristics to determine whether CTD or EUS is best suited for drainage of a particular PFC. Technical outcomes and safety of both techniques were also compared.

RESULTS

Of 53 patients with PFCs, CTD was technically successful in 30 (57%) and failed in 23 (43%). PFC regional location was the pancreatic head in 16, the body in 20, and the tail in 17; in these locations, CTD was successful in 13 (81%), 17 (85%), and 0, respectively. The causes of failed CTD were absence of luminal compression (LC) in 20, difficulty with scope positioning in 2, and bleeding with attempted drainage (portal hypertension) in 1. One PFC drained by CTD was later diagnosed as necrotic sarcoma. Of the 23 patients who failed CTD and underwent EUS, an alternate diagnosis of mucinous neoplasm was made in 2 patients, and EUS-guided drainage was successful in the other 21 patients (100%). Although CTD failed in all PFCs in the tail, all were successfully drained by EUS. In the pancreatic-head region, only those PFCs superior to pancreas and extending into porta hepatis (n = 3) required drainage by EUS. In the pancreatic body, only PFCs that developed bleeding from a transmural puncture or without definitive LC because of gastric mural edema (albumin <1.5 mg/dL, n = 2) required EUS drainage. When compared with PFCs at other locations, those in the tail were best accessed by EUS (P < .001). Patients with luminal compression at CT were significantly more likely to undergo successful drainage by CTD (adjusted odds ratio [OR] 13.6; P = .02). When compared with CTD, EUS drainages were longer in duration (40 versus 75 minutes; P < .001), with similar rates of PFCs resolution (90% versus 95%). Although bleeding occurred in 1 patient in the CTD group, no complications were encountered in patients who underwent EUS-guided drainage. PFCs located at the tail of the pancreas were more likely to require drainage by EUS than CTD (adjusted OR 22.9, P = .003) when adjusted for the presence of luminal compression at CT, size of the PFC, serum albumin, and etiology of pancreatitis.

LIMITATIONS

Nonrandomized study.

CONCLUSIONS

Because a majority of PFCs can be drained by CTD in a shorter duration, with comparable outcomes, EUS-guided drainage should be reserved mainly for PFCs located at the pancreatic tail, because these are unlikely to cause luminal compression or are technically difficult to access. Also, all pseudocyst-type PFCs must be evaluated by EUS before any attempts at endoscopic drainage, because EUS identifies an alternate diagnosis in 5% of such patients.

Approaches to the drainage of pancreatic pseudocysts

PURPOSE OF REVIEW

Review the current methods for the drainage of pancreatic pseudocysts, focusing on the recent developments in the new methods of endoscopic drainage.

RECENT FINDINGS

Pancreatic pseudocysts are collections of inflammatory fluid associated with acute and chronic pancreatitis. A leak in the pancreatic ductal system is most commonly the source of the fluid accumulation in these inflammatory cavities adjacent to the pancreas. Although most pseudocysts are not symptomatic and many resolve spontaneously over time, drainage of pseudocysts is occasionally required. There are several different approaches to the drainage: surgical, radiologic, and endoscopic. Surgical drainage is accomplished using the creation of a large anastomosis between the gastrointestinal tract and the pseudocyst cavity. Radiologically, pseudocysts are drained externally using a percutaneous, transabdominal drainage catheter. Endoscopy has offered the most recent advance, using the placement of transgastric or transduodenal stents. Most recently, therapeutic endoscopic ultrasound scopes have been used to introduce large stents that provide drainage into the upper gastrointestinal tract.

SUMMARY

Of the three methods for the drainage of a pancreatic pseudocyst, only the endoscopic approach can provide minimally invasive internal drainage.

Minimally invasive approaches to the management of pancreatic pseudocysts: review of the literature

Although one third or more of pancreatic pseudocysts might resolve spontaneously, interventional therapy is required for most. Several minimally invasive management approaches are now available, including percutaneous drainage under radiologic control, endoscopic transpapillary or transmural drainage, and laparoscopic internal drainage. This paper reviews the methodology, applications, advantages, shortcomings, and results of these management approaches. A computerized search was made of the MEDLINE, PREMEDLINE, and EMBASE databases using the search words pancreatic and pseudocysts and all relevant articles in English Language or with English abstracts were retrieved. In addition, cross-references from the identified articles were reviewed. Percutaneous drainage is best applied to pseudocysts complicated with secondary infection and in critically ill patients or those unfit for surgery. Radiologic drainage, however, risks the introduction of secondary infection and the formation of an external pancreatic fistula, and is associated with high recurrence rates. Endoscopic transpapillary drainage is beneficial for pseudocysts that communicate with the pancreatic duct and when a dependent drainage could be established. Endoscopic transmural (transgastric or transduodenal) drainage offers good results in the management of suitably located pseudocysts that complicate chronic pancreatitis, but is associated with high rates of failure to drain, secondary infection, and recurrence when pseudocysts that complicate acute necrotizing pancreatitis are approached. Laparoscopic pseudocyst gastrostomy or pseudocyst jejunostomy achieves adequate internal drainage, facilitates concomitant debridement of necrotic tissue within acute pseudocysts, and achieves good results with minimal morbidity. A randomized controlled trial that compares laparoscopic and endoscopic drainage techniques of retrogastric pseudocysts of chronic pancreatitis is required.

Laparoscopic endogastric pseudocyst gastrostomy: a report of three cases

The transgastric pseudocyst-gastrostomy is the standard approach for internal drainage of persistent and large retrogastric pancreatic pseudocysts that complicate acute necrotizing pancreatitis. We report on the application of a laparoscopic endogastric approach for drainage of pancreatic pseudocysts and discuss the merits of this technique as well as of the other previously described minimally invasive approaches for the management of pancreatic pseudocysts. Between January 2001 and August 2001, three female patients presented with large symptomatic pseudocysts 3-10 months after an episode of acute necrotizing pancreatitis. Internal drainage was effected by a laparoscopic endogastric pseudocyst gastrostomy, and the necrotic pancreas was debrided. There were no conversions and no postoperative complications. The median postoperative hospital stay was 4 days (range, 3-5). All patients remain asymptomatic, and resolution of the pseudocyst was radiologically evident at a median follow-up of 6 months (range, 4-11). The laparoscopic endogastric pseudocyst gastrostomy appears to be a safe and effective minimally invasive approach for internal drainage of large retrogastric pancreatic pseudocysts and facilitates debridement of the necrotic pancreas.