Year : 2019 | Volume
: 8 | Issue : 1 | Page : 3--16
What should be known prior to performing EUS?
Christoph F Dietrich1, Paolo Giorgio Arcidiacono2, Barbara Braden3, Sean Burmeister4, Silvia Carrara5, Xinwu Cui6, Milena Di Leo5, Yi Dong7, Pietro Fusaroli8, Odd Helge Gilja9, Andrew J Healey10, Michael Hocke11, Stephan Hollerbach12, Julio Iglesias Garcia13, André Ignee14, Christian Jürgensen15, Michel Kahaleh16, Masayuki Kitano17, Rastislav Kunda18, Alberto Larghi19, Kathleen Möller20, Bertrand Napoleon21, Kofi W Oppong22, Maria Chiara Petrone2, Adrian Saftoiu23, Rajesh Puri24, Anand V Sahai25, Erwin Santo26, Malay Sharma27, Assaad Soweid28, Siyu Sun29, Anthony Yuen Bun Teoh30, Peter Vilmann31, Christian Jenssen32,
1 Medical Department 2, Caritas-Krankenhaus, Uhlandstr 7, D-97980 Bad Mergentheim, Germany; Department of Ultrasound, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
2 Pancreatico/Biliary Endoscopy & Endosonography Division, Pancreas Translational & Clinical Research Center, San Raffaele Scientific Institute, Vita Salute San Raffaele University, Milan, Italy
3 Translational Gastroenterology Unit I John Radcliffe Hospital I Oxford OX3 9DU, UK
4 Surgical Gastroenterology unit, Groote Schuur Hospital, Cape Town, South Africa
5 Humanitas Clinical and Research Center- IRCCS- Digestive Endoscopy Unit, Division of Gastroenterology, Rozzano, Milan, Italy
6 Department of Medical Ultrasound, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
7 Department of Ultrasound, Zhongshan Hospital, Fudan University, Shanghai, China
8 Department of Medical and Surgical Sciences, Gastroenterology Unit, University of Bologna/Imola Hospital, Imola, Italy
9 National Centre for Ultrasound in Gastroenterology, Haukeland University Hospital, Bergen and Department of Clinical Medicine, University of Bergen, Bergen, Norway
10 General and HPB Surgery, Royal Infirmary of Edinburgh, Edinburgh, UK
11 Medical Department, Helios Klinikum Meiningen, Germany
12 Department of Gastroenterology, Allgemeines Krankenhaus Celle, Celle, Germany
13 Department of Gastroenterology and Hepatology, Health Research Institute of Santiago de Compostela (IDIS), University Hospital of Santiago de Compostela, Santiago de Compostela, Spain
14 Medical Department 2, Caritas-Krankenhaus, Uhlandstr 7, D-97980 Bad Mergentheim, Germany
15 Department of Hepatology and Gastroenterology, Charite CCM, Berlin, Germany
16 Department of Gastroenterology, The State University of New Jersey, New Jersey, USA
17 Second Department of Internal Medicine, Wakayama Medical University, Wakayama, Japan
18 Department of Surgical Gastroenterology, Aarhus University Hospital, Aarhus, Denmark; Department of Surgery and Department of Advanced Interventional Endoscopy, University Hospital Brussels, Brussels, Belgium
19 Digestive Endoscopy Unit, IRCCS Foundation University Hospital, Policlinico A. Gemelli, Rome, Italy
20 Medical Department I/Gastroenterology, SANA Hospital Lichtenberg, Berlin, Germany
21 Digestive Endoscopy Unit, Hopital Privé J Mermoz Ramsay Générale de Santé, Lyon, France
22 HPB Unit, Freeman Hospital, Newcastle upon Tyne, UK
23 Department of Gastroenterology, Research Center of Gastroenterology and Hepatology, University of Medicine and Pharmacy of Craiova, Craiova, Romania
24 Interventional Gastroenterology, Institute of Digestive and Hepatobiliary Sciences Medanta the Medicity, Gurugram, Haryana, India
25 Center Hospitalier de l'Université de Montréal, Montreal, Canada
26 Department of Gastroenterology and Liver Diseases, Tel Aviv, Sourasky Medical Center, Tel Aviv, Israel
27 Department of Gastroenterology, Jaswant Rai Speciality Hospital, Meerut, Uttar Pradesh, India
28 Endosonography and advanced therapeutic endoscopy, Division of Gastroenterology, The American University of Beirut, Medical Center, Beirut, Lebanon
29 Endoscopy Center, ShengJing Hospital of China Medical University, Shenyang, Liaoning, China
30 Division of Upper Gastrointestinal and Metabolic Surgery, Department of Surgery, The Prince of Wales Hospital, The Chinese University of Hong Kong, Hong Kong, China
31 GastroUnit, Department of Surgery, Copenhagen University, Hospital Herlev, Denmark
32 Department of Internal Medicine, Krankenhaus Maerkisch-Oderland, D-15344 Strausberg and Brandenburg Institute of Clinical Ultrasound at Medical University Brandenburg, Germany
Dr. Christoph F Dietrich
Medical Department, Caritas-Krankenhaus, Uhlandstr 7, D-97980 Bad Mergentheim, Germany; Department of Ultrasound, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
Direct referral of patients for EUS – instead of preprocedural consultation with the endosonographer – has become standard practice (like for other endoscopic procedures) as it is time- and cost-effective. To ensure appropriate indications and safe examinations, the endosonographer should carefully consider what information is needed before accepting the referral. This includes important clinical data regarding relevant comorbidities, the fitness of the patient to consent and undergo the procedure, and the anticoagulation status. In addition, relevant findings from other imaging methods to clarify the clinical question may be necessary. Appropriate knowledge and management of the patients' anticoagulation and antiplatelet therapy, antibiotic prophylaxis, and sedation issues can avoid unnecessary delays and unsafe procedures. Insisting on optimal preparation, appropriate indications, and clear clinical referral questions will increase the quality of the outcomes of EUS. In this paper, important practical issues regarding EUS preparations are raised and discussed from different points of view.
|How to cite this article:|
Dietrich CF, Arcidiacono PG, Braden B, Burmeister S, Carrara S, Cui X, Di Leo M, Dong Y, Fusaroli P, Gilja OH, Healey AJ, Hocke M, Hollerbach S, Garcia JI, Ignee A, Jürgensen C, Kahaleh M, Kitano M, Kunda R, Larghi A, Möller K, Napoleon B, Oppong KW, Petrone MC, Saftoiu A, Puri R, Sahai AV, Santo E, Sharma M, Soweid A, Sun S, Teoh AY, Vilmann P, Jenssen C. What should be known prior to performing EUS?.Endosc Ultrasound 2019;8:3-16
|How to cite this URL:|
Dietrich CF, Arcidiacono PG, Braden B, Burmeister S, Carrara S, Cui X, Di Leo M, Dong Y, Fusaroli P, Gilja OH, Healey AJ, Hocke M, Hollerbach S, Garcia JI, Ignee A, Jürgensen C, Kahaleh M, Kitano M, Kunda R, Larghi A, Möller K, Napoleon B, Oppong KW, Petrone MC, Saftoiu A, Puri R, Sahai AV, Santo E, Sharma M, Soweid A, Sun S, Teoh AY, Vilmann P, Jenssen C. What should be known prior to performing EUS?. Endosc Ultrasound [serial online] 2019 [cited 2019 Mar 22 ];8:3-16
Available from: http://www.eusjournal.com/text.asp?2019/8/1/3/252234
Indications, clinical pathways, and techniques used for EUS may vary in different cultural contexts, countries, and EUS centers.,,,,,,,, Practicing EUS endoscopists from various regions across the world contributed to this review and discussed their standard practice with regard to currently available evidence and according to personal preference.
This study aims to discuss the pros and cons of several issues as follows:
The “nihilistic” or “puristic” approach, “I need nothing prior to EUS” versus the clinical approach (“performing EUS as a clinician, I prefer to review as much clinical data as possible prior to EUS”)Knowledge of other imaging results before EUSShould transcutaneous ultrasound (TUS) and EUS be performed by the same operator?The use of esophagogastroduodenoscopy (EGD) prior to EUSShould consenting for EUS differ from consenting for EGD?Coagulation tests prior to EUS and interventionsOther miscellaneous topics.
The authors declared that this study is not intended as a guideline, but rather an opportunity to document the current practice, allowing readers to evaluate their own pre-EUS procedures and to stimulate further discussion.
The nihilistic or puristic approach
“I need nothing prior to EUS” is the philosophy of some of the authors. For diagnostic EUS, they do not need any test results. Ideally, EUS results should not be influenced by the pretest results. EUS is an endoscopic and imaging procedure and independently from previous findings should always be performed in a standardized manner.
In Great Britain, EUS is performed not only by gastroenterologists but also by radiologists. Therefore, endosonographers should be able to perform and interpret their examinations like a radiologist, with only basic clinical information and no prior imaging.
It is important that EUS is performed in an unbiased manner and that endosonographers develop the confidence to produce independent reports, especially if they disagree with the findings on other imaging procedures. It also forces the endosonographer to do a complete, systematic examination, instead of focusing only on previously described abnormalities. If there is discordance with other imaging modalities, it may be useful to compare EUS findings to previous imaging studies after the initial EUS assessment., The endosonographer may then decide whether it is worth prolonging the procedure to focus on a potential “missed-area” or to conclude the procedure. The protagonists of the nihilistic approach state that they never look at previous imaging studies prior to EUS. Despite this, the protagonists of the “puristic” approach claim that their results and outcomes are just as good as those in centers who do consult previous imaging procedure. In any case, there are no data proving that preprocedure consultation of computed tomography (CT) or ultrasound improves the yield of EUS.
The clinical approach
“I need to have clinical and image data available prior to EUS” is the paradigm of other authors. EUS should always be used and interpreted in a clinical context. In most countries, EUS is performed by gastroenterologists, surgeons, pneumologists, and other clinicians knowing the clinical history, laboratory findings, and previous imaging data of the patients. The protagonists believe that this is a great advantage compared with the puristic approach described above. The studies suggested that the results of EUS not blinded to patient's history, clinical data, and previous imaging results are superior to the evaluation only of EUS video sequences.,
Only by knowing the full clinical context of the EUS examination, the operator can interpret the findings correctly and decide properly on performing EUS-guided sampling and therapeutic procedures. Moreover, from a practical viewpoint, as EUS is minimally invasive, it is best for the patient to undergo a strategic diagnostic workflow, knowing the relevant clinical or image data at the time of the procedure. Knowledge of the results of previous examinations may help prevent adverse events, may inform the examiner on potentially useful auxiliary procedures such as contrast-enhancement or EUS-guided sampling, and can suggest the best choice of EUS scope. For instance, dilatation of the common bile duct without obvious cause of obstruction has a completely different meaning depending on whether the liver function tests are elevated or not and whether the patient has symptoms or not.,,,
Possible underlying diseases should be known before examination.,,, Missing relevant information preprocedure might result in the need to repeat the EUS procedure. Clinical and imaging information can guide a problem-orientated EUS approach that allocates the main procedure time to answering the clinically relevant question. One example is altered anatomy or pathology of the gastrointestinal (GI) tract (postsurgical, esophageal or duodenal diverticula, and stenosis), which may prompt the examiner to be especially careful to advance the scope; to use a small-diameter EUS scope (e.g., an endobronchial ultrasound [EBUS] scope for esophageal EUS), a US-miniprobe, or a forward-viewing scope; or to decide in favor of performing EGD prior to EUS. Another example is diagnosis of mediastinal lymphadenopathy, mediastinal tumors or mediastinal staging of lung cancer: the choice of the scope (linear EUS scope vs. EBUS-scope) may depend on the location of the tumor or of the lymph nodes.,, In general, knowledge of radiological imaging is essential for planning of sampling strategies in oncological staging.,, In certain cases, knowledge of previous findings may help obviate invasive investigations with its attendant risks. In case of biochemical proof of insulinoma with EUS performed for localization, awareness of the biochemical test results means that EUS-guided sampling can be avoided.
Do We Need Other Imaging Modalities Before EUS?
Combining TUS or other cross-sectional imaging with EUS may provide complementary information, for example, in oncological staging, but also in gastric, biliary and endocrine diseases, cystic and solid pancreatic lesions, or idiopathic acute and chronic pancreatitis.,,,,,, The topic was controversially discussed because the variety of authors represented different cultural behavior, institutional preference, and medical education ranging from gastroenterologists and surgeons to radiologists performing EUS. Some of the authors learned TUS as students and as mandatory part of the specializing curriculum whereas others never learned and used ultrasound and other radiological techniques. The use of US, CT, magnetic resonance imaging (MRI), and positron-emission tomography (PET) depends on the availability and legal and specific health-care rules and local habits. The topic of imaging in relation to EUS will be discussed in a planned separate paper. Initial demonstration of pathology by EUS may facilitate the finding of the same features using subsequent high-quality TUS equipment.
One recent study demonstrated that detection of pancreatic cysts by TUS was significantly improved with correlative images from CT, MRI, or EUS. In general, TUS is rarely used in oncological staging in Anglo-Saxon countries; however, investigating the reasons for this attitude is outside the purpose of this article and might be related to training policies in gastroenterology and availability of adequate equipment. On the other hand, cross-sectional imaging is routinely included in the staging protocols in these countries. Nowadays, new high-quality compact models of ultrasound processors that are compatible with EUS and EBUS scopes are emerging to meet the needs of physicians performing both EUS,,,,,,,,, and EBUS., Although these new processors are not compatible with the standard transabdominal probes, the basic principles of ultrasound and the normal anatomy should be well known by physicians who intend to performing EUS. No consensus could be reached between the authors regarding the specific roles of TUS, EUS, CT, and MRI in the four clinical scenarios noted below. This was particularly true with respect to the value of TUS.
A thorough clinical assessment is mandatory to establish the indications for EUS which is a minimally invasive method that carries a low, but not negligible risk. In addition, it may help minimize the EUS procedural risk by optimizing the coagulation status, creating awareness of altered anatomy, or comorbid conditions, allowing planning of invasive/interventional procedures, by intubation of unstable patients, or by examination after a prolonged fasting period in case of delayed gastric emptying. Less obvious is the definition of what should be mandatory clinical information prior to EUS. However, knowing the clinical symptoms, certain blood test results, particularly liver function tests, and previous findings of other investigations will support the quality and interpretation of the EUS results. However, this statement only reflects common clinical understanding/expert opinion, while hitherto only very few studies have been published. The need of TUS as prerequisite for EUS depends on its indication. MRI or CT is helpful to evaluate the whole extent of an inflammatory process such as necrotizing pancreatitis or tumor extent in oncological examinations. In patients with abdominal/retroperitoneal lymphadenopathy of unknown cause and in patients with (suspected) lung cancer, a thoracoabdominal (PET) CT is useful before EUS (±guided sampling) while Dotanoc/Dotatoc PET-CT is useful in neuroendocrine tumors. This helps in planning the most useful technique for tissue acquisition, a reasonable sequence for the diagnostic workup and the optimal site of biopsy. In cases with solid mediastinal mass lesions on CT, a mediastinal cyst has to be ruled out prior to EUS-guided sampling.
When EUS is indicated for locoregional staging of malignancy, TUS and/or other preliminary imaging methods such as MRI, CT, and PET might be appropriate to rule out metastatic disease, which primarily determines the prognosis. CT is essential for staging of upper GI, pancreatobiliary, and thoracic malignancies and may guide the view of the endoscopist. If, for example, hepatic, lung, or skeletal metastases are detected, locoregional staging by EUS may become unnecessary. In fact, histological confirmation of metastases would determine the further therapy of the patients, while EUS would have no additional impact. In conclusion, if distant metastatic disease is found with cross-sectional imaging, in most cases, additional staging by EUS is not necessary.
The three imaging modalities (TUS, CT, and MRI) are sometimes complementary. EUS-guided sampling would be indicated if metastases are not detectable or reachable by percutaneous techniques.,,,,,[ 45] In patients with rectal cancer, CT is performed to exclude distant metastases, followed when negative by MRI to rule out or to confirm infiltration of the mesorectal fascia. In patients with distant metastases and locally advanced rectal cancer, EUS is not indicated.
For detecting metastases to the adrenals, the combined use of TUS and EUS is relevant as the right adrenal gland is better visualized with TUS and contrast-enhanced US (CEUS), whereas the left adrenal gland is more easily depicted with EUS.,,,
The assessment of resectability of ductal pancreatic adenocarcinoma is difficult and is improved by complementary use of different imaging tools (CT, TUS, and EUS).,, The vascular involvement by pancreatic cancer is often more accurately assessed by CT or MRI than by EUS. If the information is available for the endoscopist, the correct diagnosis and staging can be achieved more easily.
TUS should be performed first line in patients with suspected choledocholithiasis, since the direct confirmation of common bile duct stones or proof of dilated bile ducts in patients with elevated liver enzymes would result in direct referral to ERCP with endoscopic sphincterotomy and stone extraction. However, EUS or MRI cholangiography (MRCP) is still required prior to ERCP in cases with intermediate probability (10%–50%) of bile duct stones and no direct proof of common bile duct stones with TUS.,,, An alternative approach in the intermediate probability setting would be early cholecystectomy with on-table cholangiography followed by laparoscopic extraction or on-table ERCP in the case of positive findings. Recent meta-analysis show superiority of EUS over MRCP for the diagnosis of common bile duct stones, in particular in the case of small stones and microlithiasis., Miniprobe-EUS has shown promising results, but is rarely available.
Advanced chronic pancreatitis can be diagnosed by TUS,, while EUS due to its high spatial resolution may be more helpful to diagnose finer details in earlier stages or to exclude chronic pancreatitis. Therefore, together with secretin-enhanced MRCP, EUS may be considered the current “golden standard” for the diagnosis of chronic pancreatitis.,,,,,, TUS is appropriate before considering EUS to diagnose chronic pancreatitis. If the pancreas is well visualized (which is the case in the majority of patients),, then EUS for the diagnosis of chronic pancreatitis may be avoided., On the other hand, EUS provides valuable additional information, e.g., on ductal anatomy (pancreas divisum), and on complications (splenic vein thrombosis and small visceral pseudoaneurysm) and therefore may help plan therapeutic procedures. If inflammatory masses need to be distinguished from neoplastic lesions, it also offers the option for EUS-guided sampling which may be less risky than percutaneous biopsy by TUS.
Pancreatic focal lesions
According to the current meta-analysis, all modern imaging tools have comparably high sensitivity for the diagnosis of pancreatic cancer. However, for the detection of small pancreatic lesions, TUS and CT are definitely inferior to MRI and EUS.,, In high-risk persons for pancreatic cancer, screening algorithms utilize a combination of MRI and EUS. Currently, EUS (in particular longitudinal) is the most sensitive technique to detect small solid and cystic pancreatic lesions. Nevertheless, it should be kept in mind that even a negative pancreatic EUS examination is not capable to completely exclude the presence of pancreatic cancer in patients with a high clinical suspicion.,, The number of incidentally detected small pancreatic lesions is increasing.,, To avoid unnecessary major surgery and to allocate these lesions correctly to treatment or surveillance, accurate classification into malignant, premalignant, and benign lesions is essential. However, accuracy of all modern imaging modalities to classify focal pancreatic lesions is limited. Therefore, often, the combination of various imaging techniques and tissue diagnosis is necessary. CEUS has an approximately 90% of accuracy to differentiate pancreatic ductal adenocarcinoma from other solid pancreatic lesions and to differentiate between neoplastic and nonneoplastic pancreatic cysts.,, EUS elastography can rule out malignancy with a high level of certainty if the lesion appears soft. A stiff lesion can be either benign or malignant. From a technical standpoint with specific reference to optimal frequencies, the current CEUS techniques are considered more suitable for transabdominal use as opposed to EUS with Sonovue®.,,,,,, Therefore, TUS with CEUS should be performed in patients with suspected cystic and solid pancreatic lesions as an initial imaging tool.,,,,,,,
TUS and EUS: Should the Examiner Be the Same?
TUS should be performed by the same examiner as EUS
It is helpful and convenient if TUS and EUS are performed by the same person as the individual anatomy is then already familiar during the EUS examinations and pathologies detected by TUS can further be investigated and characterized by EUS. For logistic reasons, this will not always be possible.
TUS could be performed by any other examiner
In principle, a high-quality TUS report should precisely describe any pathological findings with respect to size, location, echogenicity, shape, delineation, as well as contrast- or elastography characteristics. It has to be taken into account that standardized reporting is mandatory for each imaging modality. Therefore, TUS could be performed by any experienced sonographer. However, good-quality images or better video sequences from the TUS examination should be available for the EUS examiner.
Points in favor of TUS and cross-sectional imaging before EUS
A high-quality TUS and/or radiological cross-sectional imaging should be performed prior to EUS in the following situations:
To rule out distant metastases in oncological patients (comment: the use of PET in oncological patients varies widely in European countries)In patients with abdominal painIn patients with larger abdominal lesionsIn patients with suspected choledocholithiasisIn patients with suspected cystic and solid pancreatic lesionsIn patients with ductal adenocarcinoma of the pancreas to evaluate resectabilityTo guide the choice of echoendoscope (radial versus longitudinal, diameter).
In some cases, unambiguous results of TUS or cross-sectional imaging techniques may render additional EUS unnecessary, whereas ambiguous results may be clarified using EUS. Another advantage of performing TUS prior to EUS may be that after detailed EUS imaging, some lesions may be followed up by TUS. This may be the case, for example, in cystic pancreatic lesions and subepithelial GI tumors in certain locations. A TUS examination may be recommended and should be performed if the area of interest is the upper esophagus including for Zenker's diverticulum (since the upper 5 cm of the esophagus can be evaluated using US), lower esophagus (since the cardia and the surrounding tissue can be evaluated), stomach, perianal region,,,,,,,,, and pancreas.,,,, The use of mediastinal ultrasound is not well known in the community, but the supra- and prevascular as well as the paratracheal regions and the aortopulmonary window can be evaluated in almost all patients. We refer to two recently published reviews on the topic.,
Points against TUS and cross-sectional imaging before EUS
A small number of indications for EUS are not associated with a potential benefit of a preliminary TUS or another cross-sectional imaging method. This includes the evaluation of subepithelial lesions in the GI tract where EUS offers the highest resolution at the point of interest compared to other techniques.,,,, TUS is not helpful in the evaluation of subepithelial lesions in the mid esophagus. Performing high-quality TUS of the entire abdomen before performing focused EUS examination is time-consuming.
In general, to know more is better than to know less. In the mirror of the clinical context, TUS and cross-sectional imaging techniques will often define whether EUS is really indicated. The strengths of EUS are the confirmation or exclusion of lesions suggested by the clinical picture or other imaging modalities, tissue confirmation, and staging of GI malignancies. Furthermore, the exact role of TUS prior to EUS is controversial, and it differs from country to country, depending on national and local traditions and available imaging technology. However, the EUS endoscopist should keep an open mind during the examination and should not always totally rely on previous imaging findings.
Do We Need EGD Prior to EUS?
Little is known about the reasons to perform EGD prior to EUS. All recommendations in EUS textbooks originate from the personal opinions of the investigators. It seems logical to assume that a prior EGD could diminish the complication rate of EUS. The pros and cons of preliminary EGD are discussed in detail in the following paragraphs.
It is mandatory for the physician approaching EUS to know the echoendoscope very well. In particular, the length of the nonflexible tip (where the transducer is located) and the oblique viewing of echoendoscopes are the most peculiar features. This is true for the linear echoendoscopes and radial technology from Olympus, whereas the radial technology from Pentax and Fujinon uses the frontal view. Due to these features, some maneuvers may be more difficult or risky than with the standard endoscope, for example, the insertion in the upper esophagus and the advancement in the descending duodenum from the bulb. EUS plays an important role in preoperative staging for esophageal cancer. However, when the echoendoscope cannot be passed through a stenotic tumor, the role of predilatation is controversial due to the risk of perforation, and the probability that these patients have locally advanced disease is very high. In a recent study on 100 patients with malignant esophageal strictures, the gastroscope could not be advanced through the stricture in 46 patients. At staging with EUS, all these patients had locally advanced disease (T3 or T4 and N0/N+). Therefore, the current guidelines do not recommend dilatation and EUS staging of stenosing esophageal cancers.,,
Points in favor of EGD before EUS
Knowledge of the anatomy of the upper GI tract of a particular patient might lower the complication rate of EUS. However, up to now, this was not proven in studies. The perforation rates of EUS have been reported as being between 0.034% and 0.22% mainly in the esophagus and the duodenal bulb, respectively. In the study of Das et al., 44% of the esophageal perforations occurred in patients who were difficult to investigate during EGD. Moreover, there is a significant risk to miss clinically meaningful luminal lesions when EUS is performed without prior EGD. This is related to the fact that echoendoscopes are not as flexible as a standard gastroscope; for example, retroflexion in the fundus is much less efficient (or even not possible) using echoendoscopes. In addition, some types of echoendoscopes are not equipped with a high-definition endoscopic view while side-viewing endoscopes do not adequately visualize the esophagus. Therefore, in particular, side-viewing echoendoscopes may miss important mucosal findings within the upper GI tract. In patients undergoing EUS for pancreaticobiliary or mediastinal indications, three studies found clinically relevant luminal lesions of the upper GI tract in 20.5%–29.7% of cases.,, A multicentric prospective study reported that EGD performed prior to EUS found luminal lesions impacting the subsequent endosonography in 9.8% of cases. Therefore, routine performance of EGD before longitudinal EUS may be worthwhile. In addition, the endoscopic appearance of the lesion, especially mucosal or submucosal lesions, can influence the performance and the result of EUS. In case of lesions of the papilla vateri, a good endoscopic view of the lesion is mandatory, because EUS alone cannot discriminate between adenomyomatosis, adenoma, and carcinomatous lesions.
The arguments in favor of EGD are described as follows:
A relevant proportion of indications for EUS are indications for EGD as well. Explanation: Detection of gastric or duodenal lesions may aid in exclusion of pancreaticobiliary pathology as the cause of the patient's clinical pictureEUS using side-viewing echoendoscopes may miss a number of clinically relevant luminal findings in the upper GI tractThe interpretation of endoscopic pictures after EUS where EGD is performed after and not before EUS is hampered by mucosal artifacts induced by EUSThe knowledge of anatomic difficulties such as a Zenker's or duodenal diverticulum may minimize the risk of perforationA prior endoscopic inspection of a tumor or a subepithelial lesion is complementary to observation by EUS.
Points against EGD before EUS
Some radial echoendoscopes from manufacturers are equipped with forward viewing optics; thus, an extra previous EGD may not be necessary. In patients with upper GI symptoms, a single EUS examination using a radial EUS scope has a similar or even higher diagnostic yield compared with combination of TUS and upper GI endoscopy, and therefore may be used as a first-line examination in these patients., The miss rate of clinically relevant lesions using a longitudinal echoendoscope to evaluate the luminal surface of the upper GI tract in one prospective multicenter study was not inferior to EGD. EGD always requires air insufflation. The removal of insufflated air for EUS may be time-consuming and incomplete. In the view of the authors, this does not pose a real problem. Performing an EGD before any EUS examination is time-consuming, and the added diagnostic information is assumed to be low in daily practice. Some of the authors believe that the endoscopic view of the echoendoscope still allows good general orientation. This statement does not reflect that most patients with an indication for EUS have an indication for a coincident EGD or had a prior EGD before. A complication rate of 0.034% for EUS and EUS-fine-needle aspiration (EUS-FNA) was reported according to a German survey. Furthermore, it was felt that this survey probably underestimated the risk of EUS. This low rate of complications following EUS suggests that systematic adoption of EGD prior to EUS would be unlikely to statistically increase the safety of the procedure. Finally, if the results of a recent EGD are known, an additional separate endoscopy may be skipped.
We suggest that EGD be performed prior to EUS in the following indications and circumstances:
In patients with upper esophageal pathology such as swallowing disorders, dysphagia, benign strictures, or a known Zenker's diverticulum and in patients with a history of difficult upper endoscopy, to reduce the risk of perforationIn patients with impaired gastric emptying to exclude gastric outlet obstructionIn patients with suspected or confirmed esophageal or gastric cancer to exclude stenosing lesions and to decide about the type of echoendoscope to use (e.g., the EBUS scope could be used for stenosing esophageal cancer)In patients with surgically altered anatomyIn patients where the endoscopic findings are subtle and difficult to identify (e.g., small subepithelial tumors).
Should Consenting for EUS Differ from EGD Consenting?
Diagnostic and therapeutic EUS will be discussed differently as the risk for each is notably different.
Similar to other endoscopic procedures, adverse events could occur during or after EUS which may relate to the diagnostic or therapeutic intervention itself or to the applied sedation. In expert hands, EUS-related complications are generally rare, mainly bleeding and perforation and depend on the type of diagnostic or therapeutic intervention. As EUS-guided drainage procedures in biliary and pancreatic disease and other EUS-guided therapeutic applications evolve, the safety profile of interventional EUS is changing. Apart from the type of procedure, the incidence of complications is associated with the experience of the endoscopist, the nature of the disease, the general health condition of the patient, and the type of echoendoscope used.,,,,,,,[112,, It is of importance that the endosonographer knows the potential risks involved for any endoscopic procedure he/she suggests for the patient and can explain the technique, intended benefit, and possible risks in simple terms.
Points in favor of the proposal that consent for EUS differs from EGD
Diagnostic EUS without EUS-guided sampling
Due to the transducer being located at the tip, radial as well as linear echoendoscopes have a nonflexible end of 4–5 cm, which makes them more rigid. The reported perforation rates of diagnostic EUS ranges between 0.03% and 0.09%, which is higher than for standard endoscopy of the upper GI tract. EUS-guided sampling may be indicated due to findings at EUS examination in a significant proportion of cases, in particular in patients with malignant disease. Therefore, for all patients receiving diagnostic EUS using a longitudinal echoendoscope, informed consent for EUS-guided sampling is advisable.
EUS-guided sampling is a procedure with an entirely different spectrum of adverse events compared to EGD. Patients who undergo EUS-guided sampling are approximately ten times more likely to suffer complications compared to patients undergoing diagnostic noninterventional EUS. In a systematic review, the overall rate of adverse events in EUS-guided sampling was estimated at 0.98%. However, the pooled complication rate of prospective studies was as high as 1.72%. The most common complications are postprocedural pain (34%), acute pancreatitis (34%), fever and infectious complications (16%), and bleeding (13%). Perforations, pneumothorax, pneumoperitoneum, and bile leaks are very uncommon risks of EUS-guided sampling. Complication rate and spectrum of EUS-guided sampling are related to several factors including operator experience and needle target. In particular, it has been reported to be considerably higher in pancreatic lesions (1.03%; only prospective studies: 2.64%) than in mediastinal lesions (0.38%). Considering only pancreatic targets, the risk was higher for cystic lesions (2.75%; prospective studies: 5.07%) than for solid lesions (0.82%; prospective studies: 2.44%). In particular, there is a considerable risk of hemorrhage, pancreatitis, and infection after EUS-guided sampling of cystic pancreatic lesions. Although prospective studies are lacking, guidelines recommend antibiotic prophylaxis for EUS-guided sampling of cystic pancreatic lesions.,,,, There is, however, also a small risk of adverse events associated with periprocedural and antibiotics (0.28%).
Overall mortality rate after EUS-guided sampling is very low (0.02% in a systematic review). Mortality rate of EUS-FNA of pancreatic cystic lesions, however, was reported to be 0.19%. An extremely rare, but potentially catastrophic complication of EUS-guided sampling of potentially resectable tumors is tumor cell seeding.,,,,,,, Therefore, the information given to the patient should specifically address the planned EUS-guided sampling procedure.
EUS-guided therapeutic interventions
EUS-guided therapeutic interventions are completely different from diagnostic procedures, with the degree of difference being dependent on what procedures are performed. EUS-guided treatment procedures carry a highly variable risk, determined by the particular type of intervention, specific patient-related factors, and the experience of the operator and the interventional team. For example, EUS-guided celiac plexus neurolysis carries a risk of major adverse events of only 0.2%, which is much lower than that of EUS-guided drainage of walled-off pancreatic necrosis or obstructed bile or pancreatic ducts, which may be as high as 10%–20%.,,,
Points against the proposal that consent for EUS differs from EGD
Diagnostic EUS and EUS-guided sampling are safe procedures. The procedural experience and sensations in experts for the patients are similar to a standard endoscopy. The consent form could be the same for EGD and diagnostic EUS since the procedural risk for both is very low. In the commonly used consent forms in Germany, the risk of perforation is mentioned but not as a higher risk than EGD. This obviously changes fundamentally if a therapeutic procedure is performed. EUS-FNA may be considered controversially discussed for small and resectable ductal adenocarcinoma, which can be directly referred to surgery. EUS-FNA is contraindicated in hilar cholangiocarcinoma in patients considered for liver transplantation, as a transperitoneal biopsy may preclude the liver transplantation procedure. EUS-FNA is controversial in GI stromal tumor (GIST) tumors due to its low sensitivity and accuracy, while most of the patients will need surgery anyway. This should be carefully considered during the informed consent process.
The consent process should enable the patient to make an informed decision balancing the individual risks of the procedure with its potential diagnostic benefit. Therefore, we need to explain the goals and techniques of diagnostic and therapeutic EUS which fundamentally differ from EGD and other diagnostic and therapeutic endoscopic techniques. The information provided to the patient before EUS-guided interventions should relate as specifically as possible to the intervention and should be based on a thorough consideration of risk factors and alternative procedures. All EUS performing units should have specific patient information leaflets and consent forms for EUS procedures available. Auditing and reviewing adverse events should be part of continuous quality improvement activities and might help reduce the occurrence of such complications in future.,,,,
In summary, a careful review of the indication for EUS procedures, optimal preparation, and knowledge of anatomical particularities which might increase the perforation risk, is mandatory to reduce the incidence of adverse events. The knowledge of the clinical background and any previous imaging, such as TUS, CT, and MR, are complementary in paving the way to achieve the best possible EUS outcome.
Do We Need Coagulation Tests Prior to EUS-Guided Sampling? Should Antiplatelet and Anticoagulant Treatment Be Stopped Before EUS-FNA?
Introduction and review of the literature
Bleeding associated with EUS-guided sampling is an infrequent event (0%–1.4% in large prospective series), and clinically significant bleeding is a very rare complication (0.23% in a Japanese national registry). However, some guidelines list EUS-FNA as a high-risk procedure for bleeding.,,,,,[,,,, A previous meta-analysis showed that the rate of bleeding complications after EUS-FNA was 0.13%. Assessments of the Japanese national database reported that the rates of severe bleeding after EUS-FNA in patients with GI submucosal and pancreatic tumors were as low as 0.44% and 0.23%, respectively., However, EUS-guided sampling in patients with continuation of antithrombotic agents may result in severe bleeding. Unfortunately, there is a paucity of prospective and controlled trials investigating the “real-life” risk of bleeding following EUS-FNA in patients in whom anticoagulants cannot be withdrawn. One recent prospective clinical study assessed the bleeding risk in 2629 consecutive patients undergoing EUS-FNA for various indications, particularly solid tumors. In 85 of 2629 patients, anticoagulants could not be withdrawn prior to EUS-FNA for fear of thromboembolic events during withdrawal. Of this small group, 2 (2.4%) patients developed severe bleeding including hemothorax and melena, requiring blood transfusions and surgical therapy in one patient. However, no thromboembolic events were observed in the remainder. Given this risk, the performance of coagulation tests prior to EUS-guided sampling may help identify patients with coagulation disorders who are at greater risk of complications. When bleeding occurs, it is most often self-limiting with no clinical consequences. Three types of bleeding are described: extraluminal bleeding, described as an echopoor leakage adjacent to the sampled mass; intracystic bleeding in case of biopsy of cystic lesions, defined as a hyperechoic area within the cyst; and intraluminal bleeding in the GI tract at the site of the needle puncture that is visible and treatable endoscopically. The incidence of the first type is reported as between 1.3% and 2.6% of procedures., The frequency of intracystic bleeding in some studies was as high as 6%,, whereas a recent meta-analysis reported a pooled bleeding rate after EUS-FNA of pancreatic cystic lesions of only 0.69%. Conservative management is recommended in cases of extraluminal bleeding., Additional endoscopic therapy has been described in rare cases of intraprocedural luminal bleeding, but the effectiveness of these measures is uncertain. After bleeding related to EUS-guided sampling, close postprocedural clinical observation should be instituted and a low threshold for CT angiography maintained.
Points in favor of routine pre-EUS coagulation testing
Although not evidence based, in some centers, coagulation tests are routinely requested prior to EUS-guided sampling. According to the guidelines, EUS-guided interventions should not be performed with a platelet count <50000/mm3 and a prothrombin time (PT)–international normalized ratio (INR) >1.5.,,,,,
Routine coagulation tests are not expensive with the results available from all laboratories within a few hours. They may identify patients with undiagnosed coagulation disorders such as hemophilia or von Willebrand disease. Preprocedural coagulation testing may, therefore, identify patients in whom EUS-guided sampling should be avoided.
Points against of routine pre-EUS coagulation testing
In some studies, bleeding did not occur following EUS-guided sampling of solid organs., The main disadvantage of routine coagulation testing relates to its poor sensitivity and specificity in predicting postoperative bleeding.,, The PT, INR, and partial thromboplastin time (PTT) neither predict nor correlate with intraoperative or postoperative hemorrhage in the absence of clinical suspicion of a bleeding disorder or coagulopathy.,,, An abnormal value of one of the above-mentioned tests cannot predict bleeding occurrence and a normal value does not ensure hemostasis.,,,, Furthermore, a platelet count is not routinely recommended without clinical suspicion of thrombocytopenia. A history of excessive bleeding, myeloproliferative disorder, use of medications that decrease the platelet count, or other risk factors elicited from the history and physical examination should be investigated with a platelet count.,, The ASGE states that, in the absence of clinical suspicion, abnormalities of hemostasis are uncommon and routine preoperative screening for coagulopathy with PT, INR, PTT, platelet count, or bleeding time, either alone or in combination, is not recommended. Given this evidence and recommendation, the routine performance of coagulation tests before EUS and EUS-guided sampling may be unnecessary.
Points in favor of stopping antiplatelet and anticoagulation medication
The risk of bleeding is moderately elevated in patients receiving nonaspirin antiplatelet or anticoagulant treatment,, but not in patients receiving aspirin monotherapy., The guidelines advise stopping anticoagulants, clopidogrel, and other thienopyridines before performing EUS-guided sampling and therapeutic interventions. Aspirin should be stopped only before EUS-guided sampling of cystic pancreatic lesions.,,,
Con: Points against stopping antiplatelet and anticoagulation medication
Bleeding events after EUS-guided sampling are rare, despite the periprocedural continuation of antithrombotic agents (e.g., aspirin or cilostazol).,,,, A few case “series” show that EUS-guided sampling and EBUS-TBNA of mediastinal lymph nodes are not associated with a significantly increased risk of procedure-related bleeding in patients who continue thienopyridine treatment.,
There is a paucity of strong evidence supporting the routine assessment of coagulation function prior to performance of EUS-guided sampling. However, guidelines do support the performance of these tests in patients at greater risk of a coagulation disorder, such as those individuals with a personal or family history suggestive of a coagulation defect or with another clear clinical indication such as cholestatic jaundice. Endoscopists should evaluate the risks of both thromboembolic events and bleeding complications before performing EUS-FNA on patients being treated with antithrombotic agents. Aspirin treatment may be continued in patients undergoing EUS sampling of solid lesions. However, EUS-guided sampling should be avoided in patients treated with oral anticoagulants or thienopyridines, regardless of the results of the coagulation tests.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
|1||Das A, Mourad W, Lightdale CJ, et al. An international survey of the clinical practice of EUS. Gastrointest Endosc 2004;60:765-70.|
|2||Luthra AK, Evans JA. Review of current and evolving clinical indications for endoscopic ultrasound. World J Gastrointest Endosc 2016;8:157-64.|
|3||Hocke M, Braden B, Jenssen C, et al. Present status and perspectives of endosonography 2017 in gastroenterology. Korean J Intern Med 2018;33:36-63.|
|4||Shil BC, Banik RK, Saha SK, et al. Initial experience with endoscopic ultrasound. Bangladesh Med Res Counc Bull 2015;41:41-5.|
|5||D'Souza SL, Holub JL, Pavic BT, et al. Multicenter evaluation of the utilization of endoscopic ultrasound. Dig Endosc 2016;28:738-43.|
|6||James PD, Hegagi M, Antonova L, et al. Regional differences in use of endoscopic ultrasonography in Ontario: A population-based retrospective cohort study. CMAJ Open 2017;5:E437-43.|
|7||Maluf-Filho F, de Oliveira JF, Mendonça EQ, et al. II brazilian consensus statement on endoscopic ultrasonography. Endosc Ultrasound 2017;6:359-68.|
|8||Dietrich CF, Barr RG, Farrokh A, et al. Strain elastography – How to do it? Ultrasound Int Open 2017;3:E137-49.|
|9||Dietrich CF, Bibby E, Jenssen C, et al. EUS elastography: How to do it? Endosc Ultrasound 2018;7:20-8.|
|10||Braden B, Jenssen C, D'Onofrio M, et al. B-mode and contrast-enhancement characteristics of small nonincidental neuroendocrine pancreatic tumors. Endosc Ultrasound 2017;6:49-54.|
|11||Dietrich CF, Sahai AV, D'Onofrio M, et al. Differential diagnosis of small solid pancreatic lesions. Gastrointest Endosc 2016;84:933-40.|
|12||Meining A, Dittler HJ, Wolf A, et al. You get what you expect? A critical appraisal of imaging methodology in endosonographic cancer staging. Gut 2002;50:599-603.|
|13||Kahl S, Glasbrenner B, Leodolter A, et al. EUS in the diagnosis of early chronic pancreatitis: A prospective follow-up study. Gastrointest Endosc 2002;55:507-11.|
|14||Malik S, Kaushik N, Khalid A, et al. EUS yield in evaluating biliary dilatation in patients with normal serum liver enzymes. Dig Dis Sci 2007;52:508-12.|
|15||Krishna N, Tummala P, Reddy AV, et al. Dilation of both pancreatic duct and the common bile duct on computed tomography and magnetic resonance imaging scans in patients with or without obstructive jaundice. Pancreas 2012;41:767-72.|
|16||Rana SS, Bhasin DK, Sharma V, et al. Role of endoscopic ultrasound in evaluation of unexplained common bile duct dilatation on magnetic resonance cholangiopancreatography. Ann Gastroenterol 2013;26:66-70.|
|17||Sotoudehmanesh R, Nejati N, Farsinejad M, et al. Efficacy of endoscopic ultrasonography in evaluation of undetermined etiology of common bile duct dilatation on abdominal ultrasonography. Middle East J Dig Dis 2016;8:267-72.|
|18||Dietrich CF, Dong Y, Jenssen C, et al. Serous pancreatic neoplasia, data and review. World J Gastroenterol 2017;23:5567-78.|
|19||Dong Y, Jürgensen C, Puri R, et al. Ultrasound imaging features of isolated pancreatic tuberculosis. Endosc Ultrasound 2018;7:119-27.|
|20||Dong Y, D'Onofrio M, Hocke M, et al. Autoimmune pancreatitis: Imaging features. Endosc Ultrasound 2018;7:196-203.|
|21||Dietrich CF, Sharma M, Chaubal N, et al. Ascariasis imaging: Pictorial essay. Z Gastroenterol 2017;55:479-89.|
|22||Dietrich CF, Annema JT, Clementsen P, et al. Ultrasound techniques in the evaluation of the mediastinum, part I: Endoscopic ultrasound (EUS), endobronchial ultrasound (EBUS) and transcutaneous mediastinal ultrasound (TMUS), introduction into ultrasound techniques. J Thorac Dis 2015;7:E311-25.|
|23||Jenssen C, Annema JT, Clementsen P, et al. Ultrasound techniques in the evaluation of the mediastinum, part 2: Mediastinal lymph node anatomy and diagnostic reach of ultrasound techniques, clinical work up of neoplastic and inflammatory mediastinal lymphadenopathy using ultrasound techniques and how to learn mediastinal endosonography. J Thorac Dis 2015;7:E439-58.|
|24||Vilmann P, Clementsen PF, Colella S, et al. Combined endobronchial and esophageal endosonography for the diagnosis and staging of lung cancer: European Society of Gastrointestinal Endoscopy (ESGE) guideline, in Cooperation with the European Respiratory Society (ERS) and the European Society of Thoracic Surgeons (ESTS). Endoscopy 2015;47:545-59.|
|25||Jenssen C, Hocke M, Fusaroli P, et al. EFSUMB guidelines on interventional ultrasound (INVUS), part IV – EUS-guided interventions: General aspects and EUS-guided sampling (Long version). Ultraschall Med 2016;37:E33-76.|
|26||Jenssen C, Hocke M, Fusaroli P, et al. EFSUMB guidelines on interventional ultrasound (INVUS), part IV – EUS-guided interventions: General aspects and EUS-guided sampling (Short version). Ultraschall Med 2016;37:157-69.|
|27||Dumonceau JM, Deprez PH, Jenssen C, et al. Indications, results, and clinical impact of endoscopic ultrasound (EUS)-guided sampling in gastroenterology: European Society of Gastrointestinal Endoscopy (ESGE) clinical guideline – updated January 2017. Endoscopy 2017;49:695-714.|
|28||Polkowski M, Palucki J, Butruk E. Transabdominal ultrasound for visualizing gastric submucosal tumors diagnosed by endosonography: Can surveillance be simplified? Endoscopy 2002;34:979-83.|
|29||Malik V, Johnston C, O'Toole D, et al. Metabolic tumor volume provides complementary prognostic information to EUS staging in esophageal and junctional cancer. Dis Esophagus 2017;30:1-8.|
|30||Barbe C, Murat A, Dupas B, et al. Magnetic resonance imaging versus endoscopic ultrasonography for the detection of pancreatic tumours in multiple endocrine neoplasia type 1. Dig Liver Dis 2012;44:228-34.|
|31||Jenssen C, Kahl S. Management of incidental pancreatic cystic lesions. Viszeralmedizin 2015;31:14-24.|
|32||Harinck F, Konings IC, Kluijt I, et al. A multicentre comparative prospective blinded analysis of EUS and MRI for screening of pancreatic cancer in high-risk individuals. Gut 2016;65:1505-13.|
|33||Wan J, Ouyang Y, Yu C, et al. Comparison of EUS with MRCP in idiopathic acute pancreatitis: A systematic review and meta-analysis. Gastrointest Endosc 2018;87:1180-8.e9.|
|34||Löhr JM, Dominguez-Munoz E, Rosendahl J, et al. United european gastroenterology evidence-based guidelines for the diagnosis and therapy of chronic pancreatitis (HaPanEU). United European Gastroenterol J 2017;5:153-99.|
|35||Jeon JH, Kim JH, Joo I, et al. Transabdominal ultrasound detection of pancreatic cysts incidentally detected at CT, MRI, or endoscopic ultrasound. Am J Roentgenol 2018;210:518-25.|
|36||Dietrich CF, Averkiou M, Nielsen MB, et al. How to perform contrast-enhanced ultrasound (CEUS). Ultrasound Int Open 2018;4:E2-15.|
|37||Sidhu PS, Cantisani V, Dietrich CF, et al. The EFSUMB guidelines and recommendations for the clinical practice of contrast-enhanced ultrasound (CEUS) in non-hepatic applications: Update 2017 (Short version). Ultraschall Med 2018;39:e2-44.|
|38||Sidhu PS, Cantisani V, Dietrich CF, et al. The EFSUMB guidelines and recommendations for the clinical practice of contrast-enhanced ultrasound (CEUS) in non-hepatic applications: Update 2017 (Long version). Ultraschall Med 2018;39:e2-44.|
|39||Fusaroli P, Jenssen C, Hocke M, et al. EFSUMB guidelines on interventional ultrasound (INVUS), part V. Ultraschall Med 2016;37:77-99.|
|40||Fusaroli P, Jenssen C, Hocke M, et al. EFSUMB guidelines on interventional ultrasound (INVUS), part V – EUS-guided therapeutic interventions (short version). Ultraschall Med 2016;37:412-20.|
|41||Dietrich CF. Contrast-enhanced endobronchial ultrasound: Potential value of a new method. Endosc Ultrasound 2017;6:43-8.|
|42||Dietrich CF, Jenssen C, Herth FJ. Endobronchial ultrasound elastography. Endosc Ultrasound 2016;5:233-8.|
|43||Schwab R, Pahk E, Lachter J. Impact of endoscopic ultrasound quality assessment on improving endoscopic ultrasound reports and procedures. World J Gastrointest Endosc 2016;8:362-7.|
|44||Hassan H, Vilmann P, Sharma V. Impact of EUS-guided FNA on management of gastric carcinoma. Gastrointest Endosc 2010;71:500-4.|
|45||Dietrich CF, Mathis G, Cui XW, et al. Ultrasound of the pleurae and lungs. Ultrasound Med Biol 2015;41:351-65.|
|46||Dietrich CF, Wehrmann T, Hoffmann C, et al. Detection of the adrenal glands by endoscopic or transabdominal ultrasound. Endoscopy 1997;29:859-64.|
|47||Jenssen C, Dietrich CF. Ultrasound and endoscopic ultrasound of the adrenal glands. Ultraschall Med 2010;31:228-47.|
|48||Trojan J, Schwarz W, Sarrazin C, et al. Role of ultrasonography in the detection of small adrenal masses. Ultraschall Med 2002;23:96-100.|
|49||Dietrich CF, Ignee A, Barreiros AP, et al. Contrast-enhanced ultrasound for imaging of adrenal masses. Ultraschall Med 2010;31:163-8.|
|50||Grützmann R, Bunk A, Kersting S, et al. Prospective evaluation of ultrasound and colour duplex imaging for the assessment of surgical resectability of pancreatic tumours. Langenbecks Arch Surg 2003;388:392-400.|
|51||Bodea R, Seicean A, Vasile T, et al. Role of computer tomography and endoscopic ultrasonography in assessing portal and superior mesenteric vessels invasion in cephalo-pancreatic adenocarcinoma. Ann Ital Chir 2017;88:336-41.|
|52||James PD, Meng ZW, Zhang M, et al. The incremental benefit of EUS for identifying unresectable disease among adults with pancreatic adenocarcinoma: A meta-analysis. PLoS One 2017;12:e0173687.|
|53||ASGE Standards of Practice Committee, Maple JT, Ben-Menachem T, et al. The role of endoscopy in the evaluation of suspected choledocholithiasis. Gastrointest Endosc 2010;71:1-9.|
|54||European Association for the Study of the Liver (EASL). Electronic address: email@example.com. EASL clinical practice guidelines on the prevention, diagnosis and treatment of gallstones. J Hepatol 2016;65:146-81.|
|55||Williams E, Beckingham I, El Sayed G, et al. Updated guideline on the management of common bile duct stones (CBDS). Gut 2017;66:765-82.|
|56||Seifert H, Wehrmann T, Hilgers R, et al. Catheter probe extraductal EUS reliably detects distal common bile duct abnormalities. Gastrointest Endosc 2004;60:61-7.|
|57||Meeralam Y, Al-Shammari K, Yaghoobi M. Diagnostic accuracy of EUS compared with MRCP in detecting choledocholithiasis: A meta-analysis of diagnostic test accuracy in head-to-head studies. Gastrointest Endosc 2017;86:986-93.|
|58||Engjom T, Sangnes DA, Havre RF, et al. Diagnostic accuracy of transabdominal ultrasound in chronic pancreatitis. Ultrasound Med Biol 2017;43:735-43.|
|59||Engjom T, Pham KD, Erchinger F, et al. Good agreement between transabdominal and endoscopic ultrasound of the pancreas in chronic pancreatitis. Ultraschall Med 2018;[Epub ahead of Print].|
|60||Catalano MF, Sahai A, Levy M, et al. EUS-based criteria for the diagnosis of chronic pancreatitis: The rosemont classification. Gastrointest Endosc 2009;69:1251-61.|
|61||Albashir S, Bronner MP, Parsi MA, et al. Endoscopic ultrasound, secretin endoscopic pancreatic function test, and histology: Correlation in chronic pancreatitis. Am J Gastroenterol 2010;105:2498-503.|
|62||Issa Y, Kempeneers MA, van Santvoort HC, et al. Diagnostic performance of imaging modalities in chronic pancreatitis: A systematic review and meta-analysis. Eur Radiol 2017;27:3820-44.|
|63||Jenssen C, Dietrich CF. Endoscopic ultrasound in chronic pancreatitis. Z Gastroenterol 2005;43:737-49.|
|64||Trikudanathan G, Walker SP, Munigala S, et al. Diagnostic performance of contrast-enhanced MRI with secretin-stimulated MRCP for non-calcific chronic pancreatitis: A comparison with histopathology. Am J Gastroenterol 2015;110:1598-606.|
|65||De Molo C, Cui XW, Pirri C, et al. Pancreas mobile. Z Gastroenterol 2013;51:1165-70.|
|66||Pirri C, Cui XW, De Molo C, et al. The pancreatic head is larger than often assumed. Z Gastroenterol 2013;51:390-4.|
|67||Kushnir VM, Wani SB, Fowler K, et al. Sensitivity of endoscopic ultrasound, multidetector computed tomography, and magnetic resonance cholangiopancreatography in the diagnosis of pancreas divisum: A tertiary center experience. Pancreas 2013;42:436-41.|
|68||Shen Z, Munker S, Zhou B, et al. The accuracies of diagnosing pancreas divisum by magnetic resonance cholangiopancreatography and endoscopic ultrasound: A systematic review and meta-analysis. Sci Rep 2016;6:35389.|
|69||Toft J, Hadden WJ, Laurence JM, et al. Imaging modalities in the diagnosis of pancreatic adenocarcinoma: A systematic review and meta-analysis of sensitivity, specificity and diagnostic accuracy. Eur J Radiol 2017;92:17-23.|
|70||Krishna SG, Rao BB, Ugbarugba E, et al. Diagnostic performance of endoscopic ultrasound for detection of pancreatic malignancy following an indeterminate multidetector CT scan: A systemic review and meta-analysis. Surg Endosc 2017;31:4558-67.|
|71||Canto MI, Hruban RH, Fishman EK, et al. Frequent detection of pancreatic lesions in asymptomatic high-risk individuals. Gastroenterology 2012;142:796-804.|
|72||Shin EJ, Topazian M, Goggins MG, et al. Linear-array EUS improves detection of pancreatic lesions in high-risk individuals: A randomized tandem study. Gastrointest Endosc 2015;82:812-8.|
|73||Klapman JB, Chang KJ, Lee JG, et al. Negative predictive value of endoscopic ultrasound in a large series of patients with a clinical suspicion of pancreatic cancer. Am J Gastroenterol 2005;100:2658-61.|
|74||Kromrey ML, Bülow R, Hübner J, et al. Prospective study on the incidence, prevalence and 5-year pancreatic-related mortality of pancreatic cysts in a population-based study. Gut 2018;67:138-45.|
|75||Best LM, Rawji V, Pereira SP, Davidson BR, Gurusamy KS. Imaging modalities for characterising focal pancreatic lesions. Cochrane Database Syst Rev 2017;4:CD010213.|
|76||Beyer-Enke SA, Hocke M, Ignee A, et al. Contrast enhanced transabdominal ultrasound in the characterisation of pancreatic lesions with cystic appearance. JOP 2010;11:427-33.|
|77||D'Onofrio M, Barbi E, Dietrich CF, et al. Pancreatic multicenter ultrasound study (PAMUS). Eur J Radiol 2012;81:630-8.|
|78||Ignee A, Jenssen C, Arcidiacono PG, et al. Endoscopic ultrasound elastography of small solid pancreatic lesions: A multicenter study. Endoscopy 2018;49:1071-9.|
|79||Săftoiu A, Dietrich CF, Vilmann P. Contrast-enhanced harmonic endoscopic ultrasound. Endoscopy 2012;44:612-7.|
|80||Ignee A, Atkinson NS, Schuessler G, et al. Ultrasound contrast agents. Endosc Ultrasound 2016;5:355-62.|
|81||Dietrich CF, Dong Y, Froehlich E, et al. Dynamic contrast-enhanced endoscopic ultrasound: A quantification method. Endosc Ultrasound 2017;6:12-20.|
|82||Dietrich CF, Averkiou MA, Correas JM, et al. An EFSUMB introduction into dynamic contrast-enhanced ultrasound (DCE-US) for quantification of tumour perfusion. Ultraschall Med 2012;33:344-51.|
|83||Cui XW, Ignee A, Baum U, et al. Feasibility and usefulness of using swallow contrast-enhanced ultrasound to diagnose Zenker's diverticulum: Preliminary results. Ultrasound Med Biol 2015;41:975-81.|
|84||Atkinson NS, Bryant RV, Dong Y, et al. WFUMB position paper. Learning gastrointestinal ultrasound: Theory and practice. Ultrasound Med Biol 2016;42:2732-42.|
|85||Atkinson NS, Bryant RV, Dong Y, et al. How to perform gastrointestinal ultrasound: Anatomy and normal findings. World J Gastroenterol 2017;23:6931-41.|
|86||Nylund K, Maconi G, Hollerweger A, et al. EFSUMB recommendations and guidelines for gastrointestinal ultrasound. Ultraschall Med 2017;38:e1-15.|
|87||Nylund K, Maconi G, Hollerweger A, et al. EFSUMB recommendations and guidelines for gastrointestinal ultrasound. Ultraschall Med 2017;38:273-84.|
|88||Barreiros AP, Hirche TO, Ignee A, et al. Indications and limitations of perineal ultrasound examination. Scand J Gastroenterol 2010;45:764-5.|
|89||Dietrich CF, Barreiros AP, Nuernberg D, et al. Perianal ultrasound. Z Gastroenterol 2008;46:625-30.|
|90||Okanobu H, Hata J, Haruma K, et al. Giant gastric folds: Differential diagnosis at US. Radiology 2003;226:686-90.|
|91||Suk KT, Lim DW, Kim MY, et al. Thickening of the gastric wall on transabdominal sonography: A sign of gastric cancer. J Clin Ultrasound 2008;36:462-6.|
|92||Sato K, Saito H, Yashima K, et al. Transabdominal ultrasonography for assessing the depth of tumor invasion in gastric cancer. Yonago Acta Med 2017;60:154-61.|
|93||Rösch T, Schusdziarra V, Born P, et al. Modern imaging methods versus clinical assessment in the evaluation of hospital in-patients with suspected pancreatic disease. Am J Gastroenterol 2000;95:2261-70.|
|94||Martínez-Noguera A, D'Onofrio M. Ultrasonography of the pancreas 1. Conventional imaging. Abdom Imaging 2007;32:136-49.|
|95||Bertolotto M, D'Onofrio M, Martone E, et al. Ultrasonography of the pancreas 3. Doppler imaging. Abdom Imaging 2007;32:161-70.|
|96||Zamboni GA, Ambrosetti MC, D'Onofrio M, et al. Ultrasonography of the pancreas. Radiol Clin North Am 2012;50:395-406.|
|97||Jenssen C, Dietrich CF. Endoscopic ultrasound of gastrointestinal subepithelial lesions. Ultraschall Med 2008;29:236-56.|
|98||Eckardt AJ, Jenssen C. Current endoscopic ultrasound-guided approach to incidental subepithelial lesions: Optimal or optional? Ann Gastroenterol 2015;28:160-72.|
|99||Ignee A, Jenssen C, Hocke M, et al. Contrast-enhanced (endoscopic) ultrasound and endoscopic ultrasound elastography in gastrointestinal stromal tumors. Endosc Ultrasound 2017;6:55-60.|
|100||Eckardt AJ, Adler A, Gomes EM, et al. Endosonographic large-bore biopsy of gastric subepithelial tumors: A prospective multicenter study. Eur J Gastroenterol Hepatol 2012;24:1135-44.|
|101||Jenssen C, Alvarez-Sánchez MV, Napoléon B, et al. Diagnostic endoscopic ultrasonography: Assessment of safety and prevention of complications. World J Gastroenterol 2012;18:4659-76.|
|102||Bang JY, Ramesh J, Hasan M, et al. Endoscopic ultrasonography is not required for staging malignant esophageal strictures that preclude the passage of a diagnostic gastroscope. Dig Endosc 2016;28:650-6.|
|103||Denzer U, Beilenhoff U, Eickhoff A, et al. S2k guideline: Quality requirements for gastrointestinal endoscopy, AWMF registry no. 021-022. Z Gastroenterol 2015;53:E1-227.|
|104||Denzer U, Beilenhoff U, Eickhoff A, et al. S2k guideline: Quality requirements for gastrointestinal endoscopy, AWMF registry no. 021-022. Z Gastroenterol 2015;53:1496-530.|
|105||Das A, Sivak MV Jr., Chak A. Cervical esophageal perforation during EUS: A national survey. Gastrointest Endosc 2001;53:599-602.|
|106||Thomas A, Vamadevan AS, Slattery E, et al. Performing forward-viewing endoscopy at time of pancreaticobiliary EUS and ERCP may detect additional upper gastrointestinal lesions. Endosc Int Open 2016;4:E193-7.|
|107||Sahakian AB, Aslanian HR, Mehra M, et al. The utility of esophagogastroduodenoscopy before endoscopic ultrasonography in patients undergoing endoscopic ultrasonography for pancreatico-biliary and mediastinal indications. J Clin Gastroenterol 2013;47:857-60.|
|108||Kim S, Hamerski C, Ghassemi K, et al. The clinical utility of evaluating the luminal upper gastrointestinal tract during linear endoscopic ultrasonography. J Clin Gastroenterol 2016;50:538-44.|
|109||Jung A, Schlag C, Becker V, et al. Endosonography for right-sided and acute upper intestinal misery: The EFRAIM study: A prospective, randomized, controlled, blinded study. United European Gastroenterol J 2013;1:329-34.|
|110||Chang KJ, Erickson RA, Chak A, et al. EUS compared with endoscopy plus transabdominal US in the initial diagnostic evaluation of patients with upper abdominal pain. Gastrointest Endosc 2010;72:967-74.|
|111||Jenssen C, Faiss S, Nürnberg D. Complications of endoscopic ultrasound and endoscopic ultrasound-guided interventions – Results of a survey among german centers. Z Gastroenterol 2008;46:1177-84.|
|112||Alvarez-Sánchez MV, Jenssen C, Faiss S, et al. Interventional endoscopic ultrasonography: An overview of safety and complications. Surg Endosc 2014;28:712-34.|
|113||Teoh AY, Dhir V, Kida M, et al. Consensus guidelines on the optimal management in interventional EUS procedures: Results from the Asian EUS group RAND/UCLA expert panel. Gut 2018;67:1209-28.|
|114||Polkowski M, Jenssen C, Kaye P, et al. Technical aspects of endoscopic ultrasound (EUS)-guided sampling in gastroenterology: European Society of Gastrointestinal Endoscopy (ESGE) technical guideline – March 2017. Endoscopy 2017;49:989-1006.|
|115||Wang KX, Ben QW, Jin ZD, et al. Assessment of morbidity and mortality associated with EUS-guided FNA: A systematic review. Gastrointest Endosc 2011;73:283-90.|
|116||Zhu H, Jiang F, Zhu J, et al. Assessment of morbidity and mortality associated with endoscopic ultrasound-guided fine-needle aspiration for pancreatic cystic lesions: A systematic review and meta-analysis. Dig Endosc 2017;29:667-75.|
|117||ASGE Standards of Practice Committee, Early DS, Acosta RD, et al. Adverse events associated with EUS and EUS with FNA. Gastrointest Endosc 2013;77:839-43.|
|118||Dietrich CF, Müller T, Bojunga J, et al. Statement and recommendations on interventional ultrasound as a thyroid diagnostic and treatment procedure. Ultrasound Med Biol 2018;44:14-36.|
|119||Dietrich CF. EFSUMB guidelines 2015 on interventional ultrasound. Med Ultrason 2015;17:521-7.|
|120||Dietrich CF, Lorentzen T, Sidhu PS, et al. An introduction to the EFSUMB guidelines on interventional ultrasound (INVUS). Ultraschall Med 2015;36:460-3.|
|121||Lorentzen T, Nolsøe CP, Ewertsen C, et al. EFSUMB guidelines on interventional ultrasound (INVUS), part I. General aspects (long version). Ultraschall Med 2015;36:E1-14.|
|122||Lorentzen T, Nolsøe CP, Ewertsen C, et al. EFSUMB guidelines on interventional ultrasound (INVUS), part I. General aspects (Short version). Ultraschall Med 2015;36:464-72.|
|123||Sidhu PS, Brabrand K, Cantisani V, et al. EFSUMB guidelines on interventional ultrasound (INVUS), part II. Diagnostic ultrasound-guided interventional procedures (Long version). Ultraschall Med 2015;36:E15-35.|
|124||Sidhu PS, Brabrand K, Cantisani V, et al. EFSUMB guidelines on interventional ultrasound (INVUS), part II. Diagnostic ultrasound-guided interventional procedures (Short version). Ultraschall Med 2015;36:566-80.|
|125||Minaga K, Takenaka M, Katanuma A, et al. Needle tract seeding: An overlooked rare complication of endoscopic ultrasound-guided fine-needle aspiration. Oncology 2017;93 Suppl 1:107-12.|
|126||Dietrich CF, Lorentzen T, Appelbaum L, et al. EFSUMB guidelines on interventional ultrasound (INVUS), part III – Abdominal treatment procedures (Short version). Ultraschall Med 2016;37:27-45.|
|127||Dietrich CF, Lorentzen T, Appelbaum L, et al. EFSUMB guidelines on interventional ultrasound (INVUS), part III – Abdominal treatment procedures (Long version). Ultraschall Med 2016;37:E1-32.|
|128||Hamada T, Yasunaga H, Nakai Y, et al. Rarity of severe bleeding and perforation in endoscopic ultrasound-guided fine needle aspiration for submucosal tumors. Dig Dis Sci 2013;58:2634-8.|
|129||Fujimoto K, Fujishiro M, Kato M, et al. Guidelines for gastroenterological endoscopy in patients undergoing antithrombotic treatment. Dig Endosc 2014;26:1-4.|
|130||Veitch AM, Vanbiervliet G, Gershlick AH, et al. Endoscopy in patients on antiplatelet or anticoagulant therapy, including direct oral anticoagulants: British Society of Gastroenterology (BSG) and European Society of Gastrointestinal Endoscopy (ESGE) guidelines. Gut 2016;65:374-89.|
|131||ASGE Standards of Practice Committee, Anderson MA, Ben-Menachem T, et al. Management of antithrombotic agents for endoscopic procedures. Gastrointest Endosc 2009;70:1060-70.|
|132||Hamada T, Yasunaga H, Nakai Y, et al. Severe bleeding and perforation are rare complications of endoscopic ultrasound-guided fine needle aspiration for pancreatic masses: An analysis of 3,090 patients from 212 hospitals. Gut Liver 2014;8:215-8.|
|133||Kawakubo K, Yane K, Eto K, et al. A prospective multicenter study evaluating bleeding risk after endoscopic ultrasound-guided fine needle aspiration in patients prescribed antithrombotic agents. Gut Liver 2018;12:353-9.|
|134||Affi A, Vazquez-Sequeiros E, Norton ID, et al. Acute extraluminal hemorrhage associated with EUS-guided fine needle aspiration: Frequency and clinical significance. Gastrointest Endosc 2001;53:221-5.|
|135||Kien-Fong Vu C, Chang F, Doig L, et al. A prospective control study of the safety and cellular yield of EUS-guided FNA or trucut biopsy in patients taking aspirin, nonsteroidal anti-inflammatory drugs, or prophylactic low molecular weight heparin. Gastrointest Endosc 2006;63:808-13.|
|136||Varadarajulu S, Eloubeidi MA. Frequency and significance of acute intracystic hemorrhage during EUS-FNA of cystic lesions of the pancreas. Gastrointest Endosc 2004;60:631-5.|
|137||Tarantino I, Fabbri C, Di Mitri R, et al. Complications of endoscopic ultrasound fine needle aspiration on pancreatic cystic lesions: Final results from a large prospective multicenter study. Dig Liver Dis 2014;46:41-4.|
|138||Veitch AM, Vanbiervliet G, Gershlick AH, et al. Endoscopy in patients on antiplatelet or anticoagulant therapy, including direct oral anticoagulants: British Society of Gastroenterology (BSG) and European Society of Gastrointestinal Endoscopy (ESGE) guidelines. Endoscopy 2016;48:385-402.|
|139||Gralnek IM, Dumonceau JM, Kuipers EJ, et al. Diagnosis and management of nonvariceal upper gastrointestinal hemorrhage: European society of gastrointestinal endoscopy (ESGE) guideline. Endoscopy 2015;47:a1-46.|
|140||Chee YL, Crawford JC, Watson HG, et al. Guidelines on the assessment of bleeding risk prior to surgery or invasive procedures. British committee for standards in haematology. Br J Haematol 2008;140:496-504.|
|141||Eloubeidi MA, Tamhane A, Varadarajulu S, et al. Frequency of major complications after EUS-guided FNA of solid pancreatic masses: A prospective evaluation. Gastrointest Endosc 2006;63:622-9.|
|142||Hara K, Yamao K, Hijioka S, et al. Prospective clinical study of endoscopic ultrasound-guided choledochoduodenostomy with direct metallic stent placement using a forward-viewing echoendoscope. Endoscopy 2013;45:392-6.|
|143||Sanders DP, McKinney FW, Harris WH. Clinical evaluation and cost effectiveness of preoperative laboratory assessment on patients undergoing total hip arthroplasty. Orthopedics 1989;12:1449-53.|
|144||Segal JB, Dzik WH; Transfusion Medicine/Hemostasis Clinical Trials Network. Paucity of studies to support that abnormal coagulation test results predict bleeding in the setting of invasive procedures: An evidence-based review. Transfusion 2005;45:1413-25.|
|145||Dzik WH. Predicting hemorrhage using preoperative coagulation screening assays. Curr Hematol Rep 2004;3:324-30.|
|146||Eika C, Havig O, Godal HC. The value of preoperative haemostatic screening. Scand J Haematol 1978;21:349-54.|
|147||Suchman AL, Mushlin AI. How well does the activated partial thromboplastin time predict postoperative hemorrhage? JAMA 1986;256:750-3.|
|148||Perez A, Planell J, Bacardaz C, et al. Value of routine preoperative tests: A multicentre study in four general hospitals. Br J Anaesth 1995;74:250-6.|
|149||Rohrer MJ, Michelotti MC, Nahrwold DL. A prospective evaluation of the efficacy of preoperative coagulation testing. Ann Surg 1988;208:554-7.|
|150||Giles E, Walton-Salih E, Shah N, et al. Routine coagulation screening in children undergoing gastrointestinal endoscopy does not predict those at risk of bleeding. Endoscopy 2006;38:508-10.|
|151||Dzankic S, Pastor D, Gonzalez C, et al. The prevalence and predictive value of abnormal preoperative laboratory tests in elderly surgical patients. Anesth Analg 2001;93:301-8.|
|152||Smetana GW, Macpherson DS. The case against routine preoperative laboratory testing. Med Clin North Am 2003;87:7-40.|
|153||ASGE Standards of Practice Committee, Pasha SF, Acosta R, et al. Routine laboratory testing before endoscopic procedures. Gastrointest Endosc 2014;80:28-33.|
|154||Nagata N, Yasunaga H, Matsui H, et al. Therapeutic endoscopy-related GI bleeding and thromboembolic events in patients using warfarin or direct oral anticoagulants: Results from a large nationwide database analysis. Gut 2018;67:1805-12.|
|155||Inoue T, Okumura F, Sano H, et al. Bleeding risk of endoscopic ultrasound-guided fine-needle aspiration in patients undergoing antithrombotic therapy. Dig Endosc 2017;29:91-6.|
|156||Meena N, Abouzgheib W, Patolia S, et al. EBUS-TBNA and EUS-FNA: Risk assessment for patients receiving clopidogrel. J Bronchology Interv Pulmonol 2016;23:303-7.|
|157||Trindade AJ, Hirten R, Slattery E, et al. Endoscopic ultrasound-guided fine-needle aspiration of solid lesions on clopidogrel may not be a high-risk procedure for bleeding: A case series. Dig Endosc 2016;28:216-9.|