EUS elastography: How to do it?

The Latest Advancements in Diagnostic Role of Endosonography of Pancreatic Lesions

Endosonography, a minimally invasive imaging technique, has revolutionized the diagnosis and management of pancreatic diseases. This comprehensive review highlights the latest advancements in endosonography of the pancreas, focusing on key technological developments, procedural techniques, clinical applications and additional techniques, which include real-time elastography endoscopic ultrasound, contrast-enhanced-EUS, EUS-guided fine-needle aspiration or EUS-guided fine-needle biopsy. EUS is well established for T-staging and N-staging of pancreaticobiliary malignancies, for pancreatic cyst discovery, for identifying subepithelial lesions (SEL), for differentiation of benign pancreaticobiliary disorders or for acquisition of tissue by EUS-guided fine-needle aspiration or EUS-guided fine-needle biopsy. This review briefly describes principles and application of EUS and its related techniques.

Endoscopic Ultrasound (EUS) Guided Elastography

Endoscopic ultrasound (EUS) is an essential technique for the management of several diseases. Over the years, new technologies have been developed to improve and overcome certain limitations related to EUS-guided tissue acquisition. Among these new methods, EUS-guided elastography, which is a real-time method for the evaluation of tissue stiffness, has arisen as one of the most widely recognized and available. At present, there are available two different systems to perform an elastographic evaluation: strain elastography and shear wave elastography. Strain elastography is based on the knowledge that certain diseases lead to a change in tissue hardness while shear wave elastography monitored shear-wave propagation and measures its velocity. EUS-guided elastography has shown in several studies high accuracy in differentiating benign from malignant lesions from many different locations, mostly in the pancreas and lymph nodes. Therefore, nowadays, there are well-established indications for this technology, mainly for supporting the management of pancreatic diseases (diagnosis of chronic pancreatitis and differential diagnosis of solid pancreatic tumors) and characterization of different diseases. However, there are more data on new potential indications for the near future. In this review, we will present the theoretical bases of this technology and we will discuss the scientific evidence to support its use.

Endoscopic ultrasonography: Enhancing diagnostic accuracy

Endoscopic ultrasound (EUS) is an essential technique for the management of several diseases. Over the years, new technologies have been developed because to improve and overcome certain limitations related to EUS guided tissue acquisition. Among these new methods, EUS guided elastography and contrast enhanced EUS has arisen as the most widely recognized and available. We will review in this manuscript the different techniques of elastography and contrast enhancement. Nowadays, there are well establish indications for advance imaging, mainly for supporting the management of pancreatic diseases (diagnosis of chronic pancreatitis and differential diagnosis of solid and cystic pancreatic tumors) and characterization of lymph nodes. However, there are more data on new potential indications for the near future.

Advances in the clinical application of ultrasound elastography in uterine imaging

Changes in tissue stiffness by physiological or pathological factors in tissue structure are identified earlier than their clinical features. Pathological processes such as uterine fibrosis, adenomyosis, endometrial lesions, infertility, and premature birth can manifest as tissue elasticity changes. In clinical settings, elastography techniques based on ultrasonography, optical coherence tomography, and magnetic resonance imaging are widely used for noninvasive measurement of mechanical properties in patients, providing valuable tool and information for diagnosis and treatment. Ultrasound elastography (USE) plays a critical role in obstetrics and gynecology clinical work because of its simplicity, non-invasiveness, and repeatability. This article reviews the recent progress of USE in uterine tumor diagnosis (especially early diagnosis and treatment effect evaluation), prediction of preterm birth, and intrauterine insemination. We believe that USE, especially shear wave elastography, may serve as a potential means to assess tissue stiffness, thereby improving the diagnosis and treatment of adenomyosis, fibroids, endometrial lesions, cervical cancer, and precise management of preterm birth and intrauterine insemination monitoring.

The expanding role of endoscopic ultrasound elastography

Endoscopic ultrasound (EUS) is an invaluable tool for assessing various GI diseases. However, using just the conventional B-mode EUS imaging may not be sufficient to accurately delineate the lesion's character. Using the principle of stress-induced tissue strain, EUS elastography (EUS-E) can help in the real-time sonographic assessment of the level of tissue stiffness or hardness of any organ of interest during a routine EUS procedure. Thus, EUS-E can better characterize the lesion's nature and highlight the more suspicious areas within an individual lesion. The most commonly studied lesions with EUS-E are the pancreatic lesions, namely, chronic pancreatitis, pancreatic cancer, and lymph nodes. However, EUS-E is gradually expanding its use for lesion characterization of the liver, bile duct, adrenals, gastrointestinal tract, and even therapy response. Moreover, the use of EUS-E along with other image enhancement techniques such as harmonic EUS and contrast-enhanced EUS can improve the accuracy of the diagnosis. However, several technical aspects need to be standardized before EUS-E can be truly used as a tool for "virtual biopsy". This review focuses on the various technical aspects of the use of EUS-E, it is established and expanding indications and an extensive outline of the various studies on EUS-E. We also discuss the current pitfalls and future trends in EUS-E.

Early detection of pancreatic tumors by advanced EUS imaging

The early detection of pancreatic ductal adenocarcinoma (PDAC) dramatically improves outcome. All available state-of-the-art imaging methods allow early detection with EUS being the best technique for exclusion of PDAC and detection of very early PDAC. Etiological differentiation of small SPL is important to guide individually tailored patients' management including radical surgery in resectable PDAC, medical (neoadjuvant or palliative intended) treatment in patients with non-resectable malignancy, pancreatic parenchyma saving strategies in some non-PDAC, and follow-up in particular in low-grade PanNEN or other small benign lesions. Multimodality EUS imaging including B-Mode assessment, elastography, contrast-enhancement and EUS-guided sampling is the most appropriate technique for diagnosis and risk assessment of small SPL. We present a review discussing modern (endoscopic) ultrasound imaging techniques including contrast enhanced ultrasound and elastography for the early detection and characterization of solid pancreatic lesions.

Endoscopic ultrasound assessment and tissue acquisition of mediastinal and abdominal lymph nodes

The differential diagnosis between benign and malignant lymph nodes (LNs) has a fundamental role in the characterization and staging of malignant conditions, as well as in subsequent patients’ management. All imaging modalities (i.e. computed tomography and magnetic resonance imaging) rely mainly on size; endoscopic ultrasound (EUS) criteria based on B-mode evaluation and Doppler features fail to adequately characterize with high specificity LNs nature. The introduction of EUS-elastography and contrast-enhanced harmonic EUS are useful techniques to increase the diagnostic yield in identifying metastatic LNs, to identify which suspicious LN should require pathological characterization and, finally, to target tissue acquisition. EUS-guided tissue acquisition (EUS-TA) is increasingly being used for diagnosing lymphadenopathy whenever the characterization modifies patients’ subsequent management and when no superficial LN is accessible. Since target therapy are currently available (i.e. lung cancer, breast cancer), EUS-TA of malignant LNs could be required to identify tumor biology. In this field, both fine needle aspiration and biopsy needles are able to guarantee accurate results with almost perfect specificity and sub-optimal sensitivity. We finally propose a diagnostic algorithm based on most recent, high-level evidence for the diagnostic approach to suspected LNs assessment.

Impact of endoscopic ultrasound elastography in pancreatic lesion evaluation

Pancreatic malignancy still becomes a major global problem and is considered as one of the most lethal cancers in the field of gastroenterology. Most patients come in the late stage of the disease due to organ’s location, and until now the treatment result is still far away from satisfaction. Early detection is still the main key for good, prolonged survival. However, discerning from other types of tumor sometimes is not easy. Endoscopic ultrasound (EUS) is still the best tool for pancreatic assessment, whereas fine-needle aspiration biopsy (FNAB) is considered as the cornerstone for further management of pancreatic malignancy. Several conditions have become a concern for EUS-FNAB procedure, such as risk of bleeding, pancreatitis, and even needle track-seeding. Recently, an artificial intelligence innovation, such as EUS elastography has been developed to improve diagnostic accuracy in pancreatic lesions evaluation. Studies have shown the promising results of EUS elastography in improving diagnostic accuracy, as well as discerning from other tumor types. However, more studies are still needed with further considerations, such as adequate operator training, expertise, availability, and its cost-effectiveness in comparison to other imaging options.

Comprehensive review of diagnostic modalities for early chronic pancreatitis

Chronic pancreatitis (CP) is a progressive condition caused by several factors and characterised by pancreatic fibrosis and dysfunction. However, CP is difficult to diagnose at an early stage. Various advanced methods including endoscopic ultrasound based elastography and confocal laser endomicroscopy have been used to diagnose early CP, although no unified diagnostic standards have been established. In the past, the diagnosis was mainly based on imaging, and no comprehensive evaluations were performed. This review describes and compares the advantages and limitations of the traditional and latest diagnostic modalities and suggests guidelines for the standardisation of the methods used to diagnose early CP.

Endoscopic Ultrasound Elastography in the Assessment of Rectal Tumors: How Well Does It Work in Clinical Practice?

Endorectal ultrasound applications in the evaluation of rectal tumors could be a useful tool in achieving proper staging of rectal cancer. The purpose of this study was to compare the efficacy of rectal tumor staging by flexible endoscopic ultrasound (EUS) with real-time elastography (RTE) using the gold standard post-surgery histological analysis of the resected tissue as the control. The second aim of our research was to establish cutoff values for the EUS-RTE strain ratio corresponding to stages by independently comparing the stiffness values obtained with histology and EUS-RTE staging in order to minimize observation bias. We evaluated the records of 130 patients with a rectal tumor confirmed by biopsy. EUS was used in 70 patients, EUS-RTE-in the other 60. We found no statistically significant differences in staging accuracy when comparing EUS to EUS-RTE. Through a correspondence method between staging assessment and the EUS-RTE stain ratio, we identified cutoff intervals for T2, T3, and T4 staging that were nonoverlapping and proved to be statistically significant in terms of EUS-RTE values (significantly different ascending values from one interval to the other). We found that EUS-RTE offers slightly better, although not statistically significant sensitivity and specificity for T and N stage predictions compared to 2D EUS. Our results showed that EUS-RTE offers slightly higher sensitivity and specificity compared to EUS. Reliable cutoff intervals were found for strain rate elastography, previously available only for shear wave elastography (SWE) which is currently unavailable on any EUS system. Thus, these commonly available EUS-RTE systems can serve as a complementary tool in the staging of rectal tumors.

Role of Endoscopic Ultrasound Elastography Strain Histograms in the Evaluation of Patients with Pancreatic Masses

BACKGROUND

The Endoscopic Ultrasound (EUS) quantitative elastography strain ratio (SR) and strain histogram (SH) methods for noninvasive pancreatic masses differentiation have been recently developed. The aim of this research was to investigate the accuracy of the diagnostic differentiation methods for patients with pancreatic masses, based on the EUS SR and SH.

METHODS

This is a prospective study involving 100 cases with pancreatic masses. Patients were classified into 2 groups: group that was diagnosed with pancreatic malignancy with positive histopathology by biopsy obtained by fine-needle aspiration or postoperative pathology (72 patients) and the group diagnosed with pancreatitis with negative pathology and follow-up for at least 1 year (28 patients).

RESULTS

Based on the ROC curve, the cut-off point for Mode 1 was set at 97. Values under it showed the presence of malignant pancreatic masses. Mode 1 achieved a sensitivity of 89% and a specificity of 43% with an overall accuracy of 76%. The predictive positive value was 70%, and the predictive negative value was 60%. The cut-off point for SR was set at 3.04, and the values were equal or above the suggested pancreatic malignancy. The SR achieved a sensitivity of 95.83%, a specificity of 61%, with an overall accuracy of 86%. The predictive positive and negative values were 86.2% and 85%, respectively.

CONCLUSION

Mode 1 SH showed good sensitivity in the identification of pancreatic malignant tumors but were disappointingly of low specificity. Higher sensitivity, specificity, and overall accuracy were obtained by using the SR.

Diagnosis and staging of lung cancer with the use of one single echoendoscope in both the trachea and the esophagus: A practical guide

Accurate staging of non-small cell lung cancer (NSCLC) is crucial for allocation to surgical, medical or multimodal treatment. EUS and endobronchial ultrasound (EBUS) have gained ground in the diagnosis and staging of lung cancer in addition to radiological imaging (e.g., computed tomography, fluoroscopy, and magnetic resonance imaging), nuclear medicine techniques (e.g. positron emission tomography, PET), combined techniques (e.g., fluorodesoxyglucosepositron emission tomography scanning), and sonographic imaging including conventional transcutaneous mediastinal and lung ultrasound. By using one single echoendoscope in both the trachea and the esophagus, surgical staging procedures (e.g. mediastinoscopy and video assisted thoracoscopy) can be avoided in a considerable proportion of patients with NSCLC.

Enhanced EUS imaging (with videos)

BACKGROUND AND AIMS

EUS remains a primary diagnostic tool for the evaluation of pancreaticobiliary disease. Although EUS combined with FNA or biopsy sampling is highly sensitive for the diagnosis of neoplasia within the pancreaticobiliary tract, limitations exist in specific clinical settings such as chronic pancreatitis. Enhanced EUS imaging technologies aim to aid in the detection and diagnosis of lesions that are commonly evaluated with EUS.

METHODS

We reviewed technologies and methods for enhanced imaging during EUS and applications of these methods. Available data regarding efficacy, safety, and financial considerations are summarized.

RESULTS

Enhanced EUS imaging methods include elastography and contrast-enhanced EUS (CE-EUS). Both technologies have been best studied in the setting of pancreatic mass lesions. Robust data indicate that neither technology has adequate specificity to serve as a stand-alone test for pancreatic malignancy. However, there may be a role for improving the targeting of sampling and in the evaluation of peritumoral lymph nodes, inflammatory pancreatic masses, and masses with nondiagnostic FNA or fine-needle biopsy sampling. Further, novel applications of these technologies have been reported in the evaluation of liver fibrosis, pancreatic cysts, and angiogenesis within neoplastic lesions.

CONCLUSIONS

Elastography and CE-EUS may improve the real-time evaluation of intra- and extraluminal lesions as an adjunct to standard B-mode and Doppler imaging. They are not a replacement for EUS-guided tissue sampling but provide adjunctive diagnostic information in specific clinical situations. The optimal clinical use of these technologies continues to be a focus of ongoing research.

Progress in Endoscopic Treatment of Hemorrhoids

Hemorrhoids are one of the most common diseases of the anorectal region. Previously, treatment for hemorrhoids included conservative treatment, outpatient treatment, and surgical treatment. The development of flexible reversible endoscopes has provided precise controllability and imaging, enabling further improvement and development of various endoscopic techniques to treat hemorrhoids. This article discusses several of these endoscopic techniques: rubber band ligation, sclerotherapy, and electrocoagulation. The development, efficacy, and advantages of these treatments are summarized and evaluated. It is expected that going forward, endoscopic technology will be further applied in clinical practice and may become the first-line method for the treatment of hemorrhoids.

General principles of image optimization in EUS

With the development of modern EUS, multiple imaging functions, transducer settings, and examination modes have become available for clinical settings. While the major determinants of the ultrasound beam are still comprised of the signal wavelength, its frequency range, and its amplitude, other modifications and calculations have gained more interest for advanced users, such as tissue harmonic imaging (THI), spatial and frequency compounding, certain versions of speckle reduction, and various Doppler/duplex settings. The goal of such techniques is a better, perhaps more realistic image, with reduced artifacts (such as speckle), better image contrast, and an improved signal-to-noise ratio. In addition, “add-ons” such as THI, which is based on the phenomenon of nonlinear distortion of acoustic signals as they travel through tissues, provide greater contrast and an enhanced spatial resolution than conventional EUS. Finally, optimization of spectral and color Doppler imaging in EUS requires experience and knowledge about the basic principles of Doppler/duplex phenomena. For these purposes, factors such as adjustment of Doppler controls, Doppler angle, color gain, spectral wall filters, and others require special attention during EUS examinations. Incorporating these advanced techniques in EUS examinations may be time-consuming and cumbersome. Hence, practical guidelines enabling endosonographers to steer safely through the large quantity of technological properties and settings (knobology) are appreciated. This review provides an overview of the role of important imaging features to be adjusted before, during, and after EUS procedures.

What does liver elastography measure? Technical aspects and methodology

Elastography can be thought as an extension of the ancient technique of palpation. After giving a short introduction to the history of elastography, the different technologies that are nowadays available and the physics behind them, the article focuses on the assessment of liver stiffness in patients with diffuse liver disease using shear wave elastography (SWE). Practical advices on how to perform the SWE techniques and on the factors that should be considered for a correct interpretation of the results are given. This paper aimed to provide a practical guide for beginners and advanced clinical users to better understand technical aspects, methodologies and terminology.

Diagnostic Value of Real-Time Elastography in Diagnosing Lymph Node Metastasis of Skin Cancer

Objective

The purpose of this study was to examine the diagnostic performance of real-time tissue elastography in detecting lymph node involvement in skin cancers.

Methodology

We retrospectively analyzed B-mode sonography and real-time elastography (RTE) images of 70 lymph nodes from 34 patients diagnosed with squamous cell carcinoma (SCC) or malignant melanoma (MM). In the B-mode examination, the appearance or loss of the hilar architecture in the lymph node, contour lobulation, and the presence of focal cortical thickening were evaluated. Elastography scores were classified according to the ratio of soft and hard areas across the lymph node on a 4-point scale system. Largely soft lymph nodes were scored as “1” and largely hard lymph nodes were scored as “4”.

Results

When patients with SCC and MM were evaluated together, the sensitivity of elastography was 94%, specificity was 70%, and the accuracy rate was 86% in detecting lymph node involvement. When both tumor groups were evaluated separately, for SCC, the sensitivity of elastography was 90%, specificity was 61%, and the accuracy rate was 80% in detecting lymph node involvement. When the receiver operating characteristic (ROC) curve was taken, the area under the curve (AUC) was 0.78 for SCC. Elastography showed full compliance with pathology in lymph node metastases of MM and the AUC was 1.00.

Conclusions

Based on our findings, RTE provides important contributions to B-mode ultrasonography (USG) in evaluating lymph node metastases of skin cancers.

Endoscopic ultrasonography elastography in the diagnosis of intrapancreatic ectopic spleen: A case report

BACKGROUND

Intrapancreatic accessory spleen (IPAS) mimics a pancreatic neoplasm on imaging studies, and due to the lack of radiological diagnostic criteria, patients undergo unnecessary distal pancreatectomies. Endoscopic ultrasonography (EUS) is a reliable and efficient diagnostic modality for pancreatic diseases. However, no EUS criteria have been established for IPAS. We present the EUS-elastography image of IPAS, which may minimize the chance of misdiagnosis in the future.

CASE SUMMARY

A 50-year-old man was referred for an EUS evaluation after computed tomography showed a hypervascular enhanced mass in the tail of the pancreas, which indicated a neuroendocrine neoplasm. EUS elastography demonstrated that the lesion of interest covered no more than 25% of the region of interest. The patient underwent distal pancreatectomy. However, the resected tissue was evaluated, and the patient was finally diagnosed with IPAS.

CONCLUSION

IPAS should be considered in patients with suspected pancreatic neuroendocrine tumors of the pancreatic tail before surgery is performed. The differentiation between IPAS and pancreatic neuroendocrine tumors can be demonstrated using EUS-elastography.

Do we need elastography for EUS?

We recently introduced a series of papers “What should be known prior to performing EUS exams.” In Part I, the authors discussed which clinical information and whether other imaging modalities are needed before embarking EUS examinations. In Part II, technical controversies on how EUS is performed were discussed from different points of view. In this article, important practical issues regarding EUS elastography will be raised and controversially discussed from very different points of view.

How to perform EUS-guided tattooing?

Recently, we introduced a series of papers describing on how to perform certain techniques and controversies in EUS. In the first paper, "What should be known before performing EUS examinations, Part I," the authors discussed clinical information and whether other imaging modalities should be needed before embarking in EUS examination. In Part II, some technical controversies on how EUS is performed are discussed from different points of view by providing the relevant available evidence. Herewith, we describe on how to perform EUS-guided fine needle tattooing (FNT) in daily practice. The aim of this paper is to discuss pros and cons for several issues including historical remarks, injecting material, technical approach, and how to perform EUS-FNT including argues in favor and against.

Clinical impact of strain histogram EUS elastography and contrast-enhanced EUS for the differential diagnosis of focal pancreatic masses: A prospective multicentric study

Background:

Recent advances in EUS techniques (real-time EUS elastography and contrast-enhanced EUS) have allowed a better characterization of focal pancreatic masses. Mean strain histograms (SHs) are considered a good parameter for the semi-quantitative evaluation of focal pancreatic masses, alongside complementary contrast-enhanced EUS parameters which can be quantified during both the early arterial and late venous phase.

Materials and Methods:

The study design was prospective, blinded, and multicentric, assessing real-time EUS elastography and contrast-enhanced EUS results for the characterization of focal pancreatic masses using parametric measurements, in comparison with pathology which is the gold standard. SHs were performed based on the embedded software of the ultrasound system, with the values being reversed as opposed to our initially published data on hue histograms. Consequently, a cutoff of 80 was derived from previous multicentric trials. Contrast-enhanced EUS also allowed the focal masses to be classified as hyper-, iso-, or hypoenhanced in comparison with the normal pancreatic parenchyma. EUS-FNA was then performed for all patients, with a positive cytological diagnosis taken as a final proof of malignancy for the pancreatic masses. The diagnoses obtained by EUS-FNA were verified further either by surgery or during a clinical follow-up of at least 6 months.

Results:

A total number of 97 consecutive patients with focal pancreatic masses were included in the study. Based on previously defined cutoffs of 80, the values of sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of the mean SHs for the diagnosis of pancreatic cancer were 100%, 29.63%, 78.65%, 100%, and 80.41%, respectively. Corresponding values for contrast-enhanced EUS (taking into consideration hypoenhencement as a predictive factor of malignancy) were 98.57%, 77.78%, 92%, 95.45%, and 92.78%, respectively. Combining contrast enhancement-EUS (hypoenhencement) and semi-quantitative EUS elastography (SH cutoffs <80), the resulting values corresponding for sensitivity, specificity, and accuracy were 98.57%, 81.48%, and 93.81%, respectively.

Conclusion:

The current study using objective parametric tools for both EUS elastography and contrast-enhanced EUS confirmed the results of previous studies and meta-analyses that indicated a complementary role for the differential diagnosis of focal pancreatic masses. Moreover, the best values for the receiver operating curves were obtained using a sequential clinical algorithm based on the initial use of elastography, followed by contrast enhancement.

The Role of Endoscopic Ultrasound and Endoscopic Resection for Gastric Glomus: A Case Series and Literature Review

Background and Objectives

Preoperative diagnosis of gastric glomus tumor is very difficult, and there are few reports regarding the endoscopic treatment of glomus tumor of the stomach. Our aim is to provide a retrospective assessment of the imaging features of endoscopic ultrasound (EUS) and treatment of choice of gastric glomus tumor.

Methods

A database of all patients with gastric glomus tumor who was treated at Shengjing Hospital of China Medical University between March 2011 and March 2017 was retrospectively analyzed. The EUS characteristics and patients’ clinical data as well as their treatment were reviewed. At the same time, we compared EUS characteristics of gastric glomus tumor with that of gastrointestinal stromal tumor (GISTs), leiomyomas, schwannomas, and ectopic pancreas.

Results

Eleven patients (3 male and 8 female patients) were included in the present study. The patients’ age ranged from 37 to 62 years (mean age, 50.1 years). Ten patients received EUS examination. Eight lesions were presented with mild-hyperechoic round or oval mass; one lesion was mild-hyperechoic oval mass with hypoechoic spots; one lesion was hypoechoic oval mass. One patient received endoscopic full-thickness resection; 3 patients were treated by endoscopic submucosal dissection; and laparoscopic resection was performed for 7 patients.

Conclusions

Gastric glomus has typical EUS features to differentiate from other submucosal tumors. Compared with surgery, endoscopic resection is also a safe and effective treatment of choice for gastric glomus tumor.

Castleman disease in the hepatic-gastric space: A case report

BACKGROUND

Castleman disease, also known as giant lymph node hyperplasia, was first reported in 1956. It is a rare benign proliferative pathological change of the lymph nodes.

CASE SUMMARY

The patient, a 33-year-old woman, had epigastric distension for half a year. Examinations were performed in a local hospital. Computed tomography scan showed round soft tissue nodules, about 5.45 cm in diameter, in the hepatic-gastric space. Endoscopic ultrasound and endoscopic ultrasound guided fine needle aspiration was performed on the patient. Rapid on-site evaluation, hematoxylin eosin staining and histopathology of the puncture smear was performed. According to the Diff-Quik staining and hematoxylin eosin staining results of preoperative endoscopic ultrasound guided fine needle aspiration puncture smears as well as the immunohistochemistry results, Castleman disease was highly suspected. A sufficient preoperative evaluation was made, and a precise surgical plan was developed. Postoperative pathology confirmed Castleman disease.

CONCLUSION

Endoscopic ultrasound guided fine needle aspiration can extract internal tissues of the tumor for histological and cytological examinations and provide accurate diagnosis as much as possible. Therefore, a sufficient preoperative evaluation can be made, and a precise surgical plan can be developed.

Prognostic significance of 14v-lymph node dissection to D2 dissection for lower-third gastric cancer

BACKGROUND

Radical gastrectomy with D2 lymph node (LN) dissection is the standard surgical procedure for patients with resectable gastric cancer (GC). In the fifteenth edition of the Japanese Classification of Gastric Carcinoma, the 14v LN (LNs along the root of the superior mesenteric vein) was defined as the regional gastric LN. The efficacy of 14v LN dissection during radical distal gastrectomy for lower-third GC remains controversial.

AIM

To analyze whether the addition of 14v LN dissection improved the survival of patients with lower-third GC.

METHODS

The data from 65 patients who underwent 14v LN dissection and 65 patients treated without 14v LN dissection were selected using the propensity score-matched method from our institute database constructed between 2000 and 2012. Overall survival was compared between the groups.

RESULTS

Overall survival was similar between patients with 14v LN metastasis and those with distant metastasis (P = 0.521). Among patients with pathological stage IIIA disease, those who were treated with 14v LN dissection had a significantly higher overall survival than those treated without it (P = 0.020). Multivariate analysis showed that age < 65 years and pT2-3 stage were independent favorable prognostic factors for prolonged overall survival in patients with pathological stage IIIA disease. Patients with No. 1, No. 6, No. 8a, or No. 11p LN metastasis were at higher risk of having 14v LN metastasis.

CONCLUSION

Adding 14v LN dissection to D2 dissection during radical distal gastrectomy may improve the overall survival of patients with pathological stage IIIA lower-third GC.

Modern ultrasound imaging of pancreatic tumors

In patients with solid pancreatic lesions (SPLs), the differential diagnosis must be evaluated to determine whether radical surgery, pancreatic parenchyma-saving strategies, or follow-up is indicated. Contrast-enhanced (endoscopic) ultrasonography and elastography facilitate the further characterization of SPLs. The majority of cases of pancreatic ductal adenocarcinoma exhibit hypoenhancement with contrast-enhanced ultrasonography. Elastographically soft SPLs are benign with very few exceptions, whereas stiffer SPLs can be malignant or benign. This article reviews the current use of modern ultrasound imaging techniques, including contrast-enhanced ultrasonography and elastography, for the detection and characterization of SPLs. In particular, the unexcelled diagnostic potential of multiparametric endoscopic ultrasonography to detect and characterize small SPLs is highlighted.

Correlation between intracoronary thrombus components and coronary blood flow after percutaneous coronary intervention for acute myocardial infarction at different onset time

BACKGROUND

Acute myocardial infarction (AMI) is a leading cause of mortality. Early reperfusion to restore blood flow is crucial to successful treatment. In the current reperfusion regimen, an increasing number of patients have benefited from direct percutaneous coronary intervention (PCI). In order to understand whether there is a correlation between the components of coronary thrombosis and the absence of reflow or slow blood flow after coronary stent implantation in direct PCI, we collected data on direct PCI cases in our hospital between January 2016 and November 2018.

AIM

To investigate the correlation between intracoronary thrombus components and coronary blood flow after stent implantation in direct PCI in AMI.

METHODS

We enrolled 154 patients (85 male and 69 female, aged 36–81 years) with direct PCI who underwent thrombus catheter aspiration within < 3, 3–6 or 6–12 h of onset of AMI between January 2016 and November 2018. The thrombus was removed for pathological examination under a microscope. The patients of the three groups according to the onset time of AMI were further divided into those with a white or red thrombus. The thrombolysis in myocardial infarction (TIMI) blood flow after stent implantation was recorded based on digital subtraction angiography during PCI. The number of patients with no-reflow and slow blood flow in each group was counted. Statistical analysis was performed based on data such as onset time, TIMI blood flow.

RESULTS

There were significant differences in thrombus components between the patients with acute ST-segment elevation myocardial infarction and non-ST-segment elevation myocardial infarction (P < 0.01). In the group with PCI < 3 h after onset of AMI, there was no significant difference in the incidence of no-reflow and slow-flow between the white and red thrombus groups. In the groups with PCI 3-6 and 6-12 h after onset of AMI, there was a significant difference in the incidence of no-reflow and slow-flow between the white and red thrombus groups (P < 0.01). There was a significant correlation between the onset time of AMI and the occurrences of no-reflow and slow blood flow during PCI (P < 0.01).

CONCLUSION

In direct PCI, the onset time of AMI and color of coronary thrombus are often used to predict whether there will be no reflow or slow blood flow after stent implantation.

Long-term assessment of over-the-scope clip (OTSC) behavior after gastric application

Background: The aim of this study was to assess the long-term behavior of the over-the-scope clip (OTSC) after gastric application.Material and methods: A database of all patients who had OTSC placement with regular follow-up at a tertiary hospital between November 2013 and September 2016 was retrospectively analyzed. The incidence, time, and related adverse events of clip attachment and detachment were recorded. The relationship between the position of the clip and detachment was assessed by Fisher's exact test.Results: Seventy-two patients who had gastric OTSC placement due to iatrogenic perforations by endoscopic interventions were included in the study. The overall incidence of clip detachment was 27.8% (20/72). Fisher's exact test confirmed a significant association between clip detachment rate and clip position (p = .005): cardia 50% (3/6); gastric fundus 13.2% (5/38); gastric body 75% (9/16); and gastric antrum 25% (3/12). Except for one patient (5%; 1/20) who experienced minor gastric hemorrhage, there were no complications related to spontaneous clip detachment. There was no delayed bleeding, perforation, or obstruction due to clips staying in place in the long-term.Conclusions: Long-term gastric clip attachment appears to be safe even if spontaneous detachment occurs.

What should be known prior to performing EUS?

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.

Editorial on the Special Issue of Applied Sciences on the Topic of Elastography

n/a