A pilot study on modified endoscopic variceal ligation using endoscopic ultrasonography with color Doppler function

The Role of Endoscopic Ultrasound in Hepatology

Endoscopic ultrasound (EUS) has been an indispensable and widely used diagnostic tool in several medical fields, including gastroenterology, cardiology, and urology, due to its diverse therapeutic and diagnostic applications. Many studies show that it is effective and safe in patients with liver conditions where conventional endoscopy or cross-sectional imaging are inefficient or when surgical interventions pose high risks. In this article, we present a review of the current literature for the different diagnostic and therapeutic applications of EUS in liver diseases and their complications and discuss the potential future application of artificial intelligence analysis of EUS.

The role of endoscopic ultrasound for portal hypertension in liver cirrhosis

Chronic liver disease is still a major problem because disease progression will ultimately lead to liver cirrhosis. Portal hypertension is the hallmark in advanced liver disease management. By establishing portal vein access, endoscopic ultrasound (EUS) has been utilized in various clinical applications. In comparison to standard upper gastrointestinal endoscopy, EUS-Doppler has been shown to be a better modality for detecting esophageal and gastric varices along with peri-esophageal collateral veins, para-esophageal collateral veins, and perforating veins, and may be used to objectively predict the recurrence of bleeding. EUS-guided portal vein catheterization has also been proposed to overcome the limitations of trans-jugular approaches. The combination of EUS-elastography and azygos vein evaluation can also enhance the diagnostic accuracy of each modality. Another well-known implementation of EUS-guided procedures is in the management of ascites; particularly in paracentesis and ascitic fluid analysis. In addition, the most common clinical application of EUS in the treatment of portal hypertension is through vascular therapy or creation of intrahepatic portosystemic shunts. Major drawbacks of EUS mainly revolve around technical difficulties, the high cost of the procedure, as well as the requirement of more studies in humans to evaluate EUS-guided advanced therapeutic modalities in portal hypertension.

Role of Endoscopic Ultrasound in Liver Disease: Where Do We Stand?

As the burden of liver disease in the general populace steadily increases, so does the need for both advanced diagnostic and treatment options. Endoscopic ultrasound is a reliable diagnostic and therapeutic method that has an established role, foremost in pancreatobiliary pathology. This paper aims to summarize the growing role of endoscopic ultrasound in hepatology based on the search of the current literature. A number of applications of endoscopic ultrasound are reviewed, including both noninvasive methods and tissue acquisition in focal and diffuse liver disease, portal hypertension measurement, detection and management of gastric and esophageal varices, treatment of focal liver lesions and staging of pancreatobiliary malignancies, treatment of cystic and solid liver lesions, as well as liver abscess drainage. Both hepatologists and endoscopists should be aware of the evolving role of endoscopic ultrasound in liver disease. The inherent invasive nature of endoscopic examination limits its use to a targeted population identified using noninvasive methods. Endoscopic ultrasound is one the most versatile methods in gastroenterology, allowing immediate access with detection, sampling, and treatment of digestive tract pathology. Further expansion of its use in hepatology is immanent.

The Role of Interventional Endoscopic Ultrasound in Liver Diseases: What Have We Learnt?

Chronic liver disease (CLD) is still a major problem, where the disease progression will lead to liver cirrhosis (LC) or hepatocellular carcinoma (HCC). Portal hypertension (PH) management and loco-regional therapy for HCC have become the cornerstones in advanced liver disease management. Recently, there are studies looking at the potential role of interventional endoscopic ultrasound (EUS) in liver diseases. EUS may be useful in vascular changes of the digestive wall evaluation, performing dynamic assessment of hemodynamic changes, predicting variceal bleeding and rebleeding risk, and assessing the pharmacological effects. In PH management, EUS-guided vascular therapy-which revolves around glue injection, endovascular coil placement/embolization, and combination of both-has shown promising results. As a diagnostic modality for liver cancer, the implementation of EUS in liver diseases is currently not only limited to liver biopsy (EUS-LB) but also in shear-wave elastography (SWE) and portal pressure gradient measurement, as well as portal vein sampling. The application of EUS-guided radiofrequency ablation (EUS-RFA) and tumor injection can also overcome the limitations shown by both modalities without EUS. Nevertheless, establishing EUS as a firm diagnostic and therapeutic modality is still challenging since the performance of interventional EUS requires high expertise and adequate facilities.

Practical approach to linear EUS examination of the liver

EUS has become a substantial diagnostic and therapeutic modality for digestive tract conditions. The extent of endosonographic assessment is wide, and, among others, it allows for the evaluation of liver anatomy and related pathologies. Moreover, EUS assessment has proved more accurate in detecting small focal liver lesions missed by standard imaging examinations such as computed tomography or magnetic resonance. Endosonographically, various liver segments can be visualized by transgastric and transduodenal scanning following anatomical landmarks, thus providing arranged systematic examination. In addition, knowledge considering the correct position during examination is crucial for EUS-guided procedures such as hepaticogastrostomy, ablation of tumors, and measurement of portal pressure gradient. The evolution of EUS-guided intervention has contributed to the increasing importance of understanding the hepatic segmental anatomy during the EUS examination.

The Role of Endoscopic Ultrasound for Esophageal Varices

Esophageal varices are caused by the development of collateral circulation in the esophagus as a result of portal hypertension. It is important to administer appropriate preventive treatment because bleeding varices can be fatal. Esophageal varices have complex and diverse hemodynamics, and there are various variations for each case. Endoscopic ultrasound (EUS) can estimate the hemodynamics of each case. Therefore, observation by EUS in esophageal varices provides useful information, such as safe and effective treatment selection, prediction of recurrence, and appropriate follow-up after treatment. Although treatment for the esophagogastric varices can be performed without EUS imaging, understanding the local hemodynamics of the varices using EUS prior to treatment will lead to more safe and effective treatment. EUS observation is an indispensable tool for thorough variceal care.

The role of EUS in diagnosis and treatment of liver disorders

Background and aim  Transabdominal ultrasound (US), computed tomographic scanning (CT) and magnetic resonance imaging (MRI) are established diagnostic tools for liver diseases. Percutaneous transhepatic cholangiography is used to perform hepatic interventional procedures including biopsy, biliary drainage procedures, and radiofrequency ablation. Despite their widespread use, these techniques have limitations. Endoscopic ultrasound (EUS), a tool that has proven useful for evaluating the mediastinum, esophagus, stomach, pancreas, and biliary tract, has an expanding role in the field of hepatology complementing the traditional investigational modalities. This review aimed to assess the current scientific evidence regarding diagnostic and therapeutic applications of EUS for hepatic diseases.

A miniature ultrasound probe is useful in reducing rebleeding after endoscopic cyanoacrylate injection for hemorrhagic gastric varices

OBJECTIVE

To better assess the usefulness of miniature ultrasound probe (MUP) sonography in the evaluation of the adequacy of gastric variceal injection with cyanoacrylate to decrease the risk of post injection rebleeding.

MATERIAL AND METHODS

Sixty-nine patients with bleeding gastric varices were included in this study. Endoscopic cyanoacrylate injection was performed in the acute phase for variceal hemostasis. After injection, patients (n = 34) included in the MUP group prospectively received endoscopic ultrasonography (EUS) with MUP during each scheduled endoscopic follow-up session. Patients (n = 35) in the control group who were included historically were followed up with the same interval with endoscopy only.

RESULTS

Four (11.4%) patients in the control group received reinjection, and there were 10 episodes of rebleeding in 7 (20.0%) patients. Nine (26.5%) patients received reinjection due to inadequate obturation as judged by EUS. There were six episodes of rebleeding in three (8.8%) patients in the MUP group. The free-of-rebleeding rate for the MUP group was significantly higher than that for the control group (p < 0.05). The cumulative survival for the MUP group was slightly better than that for the control group but was not statistically significant. The patients' compliance in both groups was similar. The endosonographers considered the performance of MUP sonography to be convenient.

CONCLUSIONS

MUP sonography is useful for the evaluation of the adequacy of tissue adhesive obturation of gastric varices that may reduce the probability of rebleeding.

How do we select an endoscopic treatment for esophageal varices on the basis of hemodynamic analysis using color Doppler endoscopic ultrasonography

We investigated the hemodynamics of the left gastric vein (LGV) and its association with variceal recurrence using color Doppler endoscopic ultrasonography (CD-EUS). The long-term results of our technique known as combined ligation and sclerotherapy showed that the risk of variceal recurrence decreased after long-term follow-up with timely repeated therapies. On the basis of the hemodynamic background of these results, it was suggested that the posterior branch of the LGV could have developed as an extravariceal shunt, whereas the anterior branch, which directly feeds varices, seemed to disappear through long-term follow-up with repeated treatments. In the study comparing CD-EUS findings between patients with and without variceal recurrence, dominance between anterior and posterior branches and the hepatofugal flow velocity of the LGV were suggested to be important factors contributing to variceal recurrence. We consider that these patients may require more intense therapy, such as the mucofibrosing technique or a technique to obliterate both the varices and their donor vessels.

Endoscopic ultrasonography and portal hypertension: where are we in 2009?

Endoscopic ultrasonography is currently a sensitive diagnostic and therapeutic tool with established indications, but its role in the management of portal hypertension is not well defined. This article briefly reviews indications, technologic improvements, diagnostic and interventional applications of endoscopic ultrasonography in portal hypertension.

Endoscopic ultrasonography in the diagnosis and management of portal hypertension. Where are we next?

Endoscopic ultrasonography has recently emerged as an accurate, non-invasive and reproducible alternative means of providing data for patients with portal hypertension. It is well established that endoscopic ultrasonography is more sensitive than endoscopy in the diagnosis of gastric varices. Dilated venous abnormalities outside the gastrooesophageal lumen, which cannot be diagnosed by endoscopy, are readily visible with endoscopic ultrasonography or miniature probes. Endoscopic ultrasonography is also useful to predict the risk of variceal recurrence and thus the risk of rebleeding after endotherapy which cannot be reliably predicted using endoscopy alone. The introduction of echo endoscopes equipped with Doppler facilities has allowed the sonographic visualisation of the vessels and the evaluation of vascular blood flow along with possible morphologic and haemodynamic changes after endoscopic or pharmacological therapy. However, despite its theoretical advantages, relative evidence suggests that in the clinical setting of portal hypertension, endoscopic ultrasonography remains an investigational tool with limited clinical applications.

Photodynamic effects on rabbit auricular veins after photosensitization with porfimer sodium: Implications of the results with respect to the treatment of esophageal varices with photodynamic therapy

BACKGROUND

There are numerous clinical applications for photodynamic therapy in the GI tract. The principal reason for the wide variety of lesions amenable to photodynamic therapy is the ability to treat large areas of mucosa without the need for complete visualization. This report describes observed hemodynamic and histologic changes in rabbit auricles after photodynamic therapy and the feasibility of photodynamic therapy for esophageal varices.

METHODS

Porfimer sodium and an argon-dye laser (630 nm, 300 mW/cm(2)) were used. Twenty rabbits were grouped according to porfimer sodium dose: group 1 (2.0 mg/kg, n = 10); group 2 (1.0 mg/kg, n = 6); group 3 (0.2 mg/kg, n = 4). Rabbit auricular veins were classified according to time duration of laser illumination: V(0), no illumination; V(5), 5 minutes; V(10), 10 minutes; V(15), 15 minutes. Hemodynamic changes were observed with a laser Doppler blood flow meter. Histologic changes were evaluated by light microscopy.

RESULTS

For groups 1 and 2, there was a significant decrease in blood flow for V(15) after photodynamic therapy, but not in group 3. There was a significant difference in the grade of thrombus between V(5) and V(15) in groups 1 and 2, and between V(10) and V(15) in group 2. There was a significant difference in the grade of venous dilation (congestion) for V(15) between groups 1 and 3 (p < 0.05, Kruskal-Wallis test).

CONCLUSIONS

Endoscopic photodynamic therapy could possibly improve the outcome for endoscopic treatment of esophageal varices beyond that achieved by sclerotherapy or band ligation alone.

Review article: current endoscopic therapeutic options in the management of variceal bleeding

Variceal bleeding is a frequent and life-threatening complication of portal hypertension. The first episode of variceal bleeding is not only associated with a high mortality, but also with a high recurrence rate in those who survive. Therefore, many studies and randomized clinical trials have focused on different therapeutic strategies aiming to prevent the first episode of variceal bleeding (primary prophylaxis), to control haemorrhage during the acute bleeding episode (emergency treatment), and to prevent re-bleeding (secondary prophylaxis). These strategies involve pharmacological, endoscopic, surgical, and interventional radiological modalities. This review concentrates on the clinical aspects of the endoscopic modalities used to treat oesophageal variceal haemorrhage, including variceal injection sclerotherapy, variceal band ligation, and the use of tissue adhesives (glue) and their substitutes. We also draw conclusions from the available literature regarding the use of endoscopic modalities in primary prophylaxis, emergency treatment, and secondary prophylaxis of variceal re-bleeding. The management of gastric varices and variceal bleeding during pregnancy is also addressed.

EUS in cirrhotic patients with and without prior variceal hemorrhage in comparison with noncirrhotic control subjects

BACKGROUND

Endoscopic ultrasound (EUS) was used to evaluate cirrhotic patients with and without prior variceal hemorrhage. The findings were compared with those of EUS in noncirrhotic control subjects to determine EUS features indicative of cirrhosis and of a risk for variceal hemorrhage.

METHODS

Patients with cirrhosis undergoing indicated endoscopic screening for varices or surveillance after endoscopic therapy for variceal hemorrhage were studied and compared with healthy noncirrhotic control patients undergoing EUS for benign conditions.

RESULTS

Sixty-six cirrhotic patients (31 with prior hemorrhage) and 32 control patients were studied. Nonhemorrhage cirrhotic patients had more severe liver disease by Child's class (p = 0.02) and less beta-adrenergic blocker usage (p < 0.0001). Paraesophageal varices were detected in 97% of cirrhotic patients and 3% of control patients (p < 0.001) and were a more sensitive predictor of cirrhosis than varices at endoscopy (74%, p < 0.0001). Azygos vein and thoracic duct diameters, and gastric mucosa and submucosa thickness were greater for cirrhotic than control patients (p < 0.001). More hemorrhage patients had large (5 mm or greater) paraesophageal varices (odds ratio 3.1: 95% CI [1.1, 8.3]; p < 0.05) and paragastric varices (odds ratio 3.7: 95% CI [1.3, 10.2]; p = 0.01). Paraesophageal varix size correlated with ascites (p = 0.03) and, for nonhemorrhage patients, with Child's class (p < 0.01).

CONCLUSIONS

Paraesophageal and paragastric varices correlate with the presence and severity of liver disease and portal hypertension. These data support the hypothesis that large paraesophageal and paragastric varices (5 mm or greater) may be risk factors for variceal hemorrhage, an observation that merits further prospective study. Cirrhosis causes dilation of the azygos vein and thoracic duct and thickening of gastric mucosa and submucosa.

Esophageal varices. I. Clinical presentation, medical therapy, and endoscopic therapy

The last half century has witnessed great advances in the understanding of the pathogenesis and natural history of portal hypertension in cirrhotics. Several pharmacologic and endoscopic techniques have been developed for the treatment of portal hypertension. The use of these agents in a given patient must be based on an understanding of the stage in the natural history of the disease and the relative efficacy and safety of the available treatment options.

Left gastric vein hemodynamics and variceal recurrence in patients undergoing prophylactic endoscopic ligation of high-risk esophageal varices

BACKGROUND

Early recurrence of esophageal varices remains problematic after endoscopic variceal ligation. To evaluate the efficacy of prophylactic endoscopic ligation for esophageal varices at high risk for bleeding, the relationship between left gastric vein hemodynamics and variceal recurrence was investigated.

METHODS

Thirty-five patients with cirrhosis underwent endoscopic variceal ligation. Angiography was performed in all patients before treatment and after eradication of varices to study left gastric vein hemodynamics.

RESULTS

Before treatment, 12 patients had hepatopetal flow in the left gastric vein (type I), 17 had hepatofugal flow (type II), and 6 had hepatofugal flow with an extra-esophageal shunt (type III). In type I and III patients, the direction of blood flow in the left gastric vein did not change after eradication of varices. Type II patients showed bi-directional flow in the left gastric vein after treatment. Varices recurred in all but one type II patient and in one type I patient during follow-up (mean 36.7 months). The 2-year recurrence-free rate was higher in type I patients (p = 0.0001) and type III patients (p = 0.0002) than in type II patients.

CONCLUSIONS

Prophylactic ligation seems to be a safe and useful procedure, especially in patients with type I or III hemodynamics in the left gastric vein before treatment.