Endoscopic procedures in hepatology: Current trends and new developments

[Endo-Hepatology: New Endoscopic Solutions for Old Hepatological Problems]

With the rapid development of endoscopic ultrasound (EUS), diagnostic and therapeutic platforms have emerged that are applicable in hepatology. New tools such as EUS-guided portal pressure measurement (in combination with EUS-guided liver biopsy) or EUS-guided variceal obliteration using coils and glue present attractive procedures that can potentially overcome the limitations of current gold standards. In this review article, we provide an overview of these new 'endo-hepatology' techniques and highlight their current role in the treatment of liver diseases.

Comprehensive approach to esophageal variceal bleeding: From prevention to treatment

Esophageal variceal bleeding is a severe complication often associated with portal hypertension, commonly due to liver cirrhosis. Prevention and treatment of this condition are critical for patient outcomes. Preventive strategies focus on reducing portal hypertension to prevent varices from developing or enlarging. Primary prophylaxis involves the use of non-selective beta-blockers, such as propranolol or nadolol, which lower portal pressure by decreasing cardiac output and thereby reducing blood flow to the varices. Endoscopic variceal ligation (EVL) may also be employed as primary prophylaxis to prevent initial bleeding episodes. Once bleeding occurs, immediate treatment is essential. Initial management includes hemodynamic stabilization followed by pharmacological therapy with vasoactive drugs such as octreotide or terlipressin to control bleeding. Endoscopic intervention is the cornerstone of treatment, with techniques such as EVL or sclerotherapy applied to directly manage the bleeding varices. In cases where bleeding is refractory to endoscopic treatment, transjugular intrahepatic portosystemic shunt may be considered to effectively reduce portal pressure. Long-term management after an acute bleeding episode involves secondary prophylaxis using beta-blockers and repeated EVL sessions to prevent rebleeding, complemented by monitoring and managing liver function to address the underlying disease. In light of new scientific evidence, including the findings of the study by Peng et al, this editorial aims to review available strategies for the prevention and treatment of esophageal varices.

Modernizing metabolic dysfunction-associated steatotic liver disease diagnostics: the progressive shift from liver biopsy to noninvasive techniques

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a growing public health concern worldwide. Liver biopsy is the gold standard for diagnosing and staging MASLD, but it is invasive and carries associated risks. In recent years, there has been significant progress in developing noninvasive techniques for evaluation. This review article discusses briefly current available noninvasive assessments and the various liver biopsy techniques available for MASLD, including invasive techniques such as transjugular and transcutaneous needle biopsy, intraoperative/laparoscopic biopsy, and the evolving role of endoscopic ultrasound-guided biopsy. In addition to discussing the various biopsy techniques, we review the current state of knowledge on the histopathologic evaluation of MASLD, including the various scoring systems used to grade and stage the disease. We also explore current and alternative modalities for histopathologic evaluation, such as whole slide imaging and the utility of immunohistochemistry. Overall, this review article provides a comprehensive overview of the progress in liver biopsy techniques for MASLD and compares invasive and noninvasive modalities. However, beyond clinical trials, the practical application of liver biopsy may be limited, as ongoing advancements in noninvasive fibrosis assessments are expected to more effectively identify candidates for MASLD treatment in real-world settings.

EUS-Guided Vascular Interventions: Recent Advances

Endoscopic ultrasound (EUS)-guided vascular interventions were first reported in 2000 in a study that evaluated the utility of EUS in sclerotherapy of esophageal varices. Currently, gastric variceal therapy and portosystemic pressure gradient (PPG) measurements are the most widely utilized applications. Ectopic variceal obliteration, splenic artery embolization, aneurysm/pseudoaneurysm treatment, portal venous sampling, and portosystemic shunt creation using EUS are some of the other emerging interventions. Since the release of the American Gastroenterological Association (AGA)'s commentary in 2023, which primarily endorses EUS-guided gastric variceal therapy and EUS-PPG measurement, several new studies have been published supporting the use of EUS for various vascular conditions. In this review, we present the recent advances in this field, critically appraising new studies and trials.

Role of endoscopy in hepatology

The growing and evolving field of EUS and advanced hepatobiliary endoscopy has amplified traditional upper gastrointestinal endoscopy and unveiled novel options for remaining unsolved hepatobiliary issues, both diagnostically and therapeutically. This conceptually appealing and fascinating integration of endoscopy within the practice of hepatology is referred to as 'endo-hepatology'. Endo-hepatology focuses on the one hand on disorders of the liver parenchyma and liver vasculature and of the hepatobiliary tract on the other hand. Applications hanging under the umbrella of endohepatology involve amongst others EUS-guided liver biopsy, EUS-guided portal pressure measurement, EUS-guided portal venous blood sampling, EUS-guided coil & glue embolization of gastric varices and spontaneous portosystemic shunts as well as ERCP in the challenging context of (decompensated cirrhosis) and intraductal cholangioscopy for primary sclerosing cholangitis. Although endoscopic proficiency however does not necessarily equal in an actual straightforward end-solution for currently persisting (complex) hepatobiliary situations. Therefore, endohepatology continues to generate high-quality data to validate and standardize procedures against currently considered (best available) "golden standards" while continuing to search and trying to provide novel minimally invasive solutions for persisting hepatological stalemate situations. In the current review, we aim to critically appraise the status and potential future directions of endo-hepatology.

Gut Microbiota and Sinusoidal Vasoregulation in MASLD: A Portal Perspective

Metabolic dysfunction-associated steatotic liver disease (MASLD) is a common condition with heterogeneous outcomes difficult to predict at the individual level. Feared complications of advanced MASLD are linked to clinically significant portal hypertension and are initiated by functional and mechanical changes in the unique sinusoidal capillary network of the liver. Early sinusoidal vasoregulatory changes in MASLD lead to increased intrahepatic vascular resistance and represent the beginning of portal hypertension. In addition, the composition and function of gut microbiota in MASLD are distinctly different from the healthy state, and multiple lines of evidence demonstrate the association of dysbiosis with these vasoregulatory changes. The gut microbiota is involved in the biotransformation of nutrients, production of de novo metabolites, release of microbial structural components, and impairment of the intestinal barrier with impact on innate immune responses, metabolism, inflammation, fibrosis, and vasoregulation in the liver and beyond. The gut-liver axis is a conceptual framework in which portal circulation is the primary connection between gut microbiota and the liver. Accordingly, biochemical and hemodynamic attributes of portal circulation may hold the key to better understanding and predicting disease progression in MASLD. However, many specific details remain hidden due to limited access to the portal circulation, indicating a major unmet need for the development of innovative diagnostic tools to analyze portal metabolites and explore their effect on health and disease. We also need to safely and reliably monitor portal hemodynamics with the goal of providing preventive and curative interventions in all stages of MASLD. Here, we review recent advances that link portal metabolomics to altered sinusoidal vasoregulation and may allow for new insights into the development of portal hypertension in MASLD.

Endoscopic Ultrasound-Guided Tissue Sampling for the Cytohistological Diagnosis of Focal Liver Lesions

BACKGROUND

Focal liver lesions (FLL) often require cytohistological evaluation. Endoscopic Ultrasound (EUS)-guided tissue acquisition (EUS-TA) is highly accurate in diagnosing pancreatic and gastrointestinal malignancies. The aim of our study was to evaluate the role of EUS-TA in the characterization of FLL.

METHODS

A retrospective analysis of a prospective database of patients who underwent EUS-TA for the evaluation of FLL. Diagnostic yield, adverse events and factors associated with diagnostic yield were evaluated as endpoints. The effect of variables such as needle size, lesion size, rapid on-site evaluation (ROSE) and the use of cytological or histological needles were analyzed.

RESULTS

A total of 114 cases were included (mean age 68.05 ± 11.35 years, 64 male). A correct diagnosis was made using EUS-TA in 100 of the 114 cases (diagnostic yield of 88%). The EUS-TA of additional extrahepatic lesions during the same EUS procedure increased the diagnostic yield to 94%. No adverse events were reported. Multivariate analysis did not identify any factor influencing the diagnostic yield.

CONCLUSIONS

EUS-TA is a highly accurate and safe technique for the differential diagnosis of FLL and could be considered as the primary approach in this setting.

Gastrointestinal tract disease detection via deep learning based structural and statistical features optimized hexa-classification model

BACKGROUND

Gastrointestinal tract (GIT) diseases impact the entire digestive system, spanning from the mouth to the anus. Wireless Capsule Endoscopy (WCE) stands out as an effective analytic instrument for Gastrointestinal tract diseases. Nevertheless, accurately identifying various lesion features, such as irregular sizes, shapes, colors, and textures, remains challenging in this field.

OBJECTIVE

Several computer vision algorithms have been introduced to tackle these challenges, but many relied on handcrafted features, resulting in inaccuracies in various instances.

METHODS

In this work, a novel Deep SS-Hexa model is proposed which is a combination two different deep learning structures for extracting two different features from the WCE images to detect various GIT ailment. The gathered images are denoised by weighted median filter to remove the noisy distortions and augment the images for enhancing the training data. The structural and statistical (SS) feature extraction process is sectioned into two phases for the analysis of distinct regions of gastrointestinal. In the first stage, statistical features of the image are retrieved using MobileNet with the support of SiLU activation function to retrieve the relevant features. In the second phase, the segmented intestine images are transformed into structural features to learn the local information. These SS features are parallelly fused for selecting the best relevant features with walrus optimization algorithm. Finally, Deep belief network (DBN) is used classified the GIT diseases into hexa classes namely normal, ulcer, pylorus, cecum, esophagitis and polyps on the basis of the selected features.

RESULTS

The proposed Deep SS-Hexa model attains an overall average accuracy of 99.16% in GIT disease detection based on KVASIR and KID datasets. The proposed Deep SS-Hexa model achieves high level of accuracy with minimal computational cost in the recognition of GIT illness.

CONCLUSIONS

The proposed Deep SS-Hexa Model progresses the overall accuracy range of 0.04%, 0.80% better than GastroVision, Genetic algorithm based on KVASIR dataset and 0.60%, 1.21% better than Modified U-Net, WCENet based on KID dataset respectively.