Drainage therapy for malignant biliary obstruction (MBO) includes trans-papillary endoscopic retrograde biliary drainage (ERBD), percutaneous transhepatic biliary drainage (PTBD), and transgastrointestinal endoscopic ultrasound-guided biliary drainage (EUS-BD). With the development of chemotherapy, many MBO cases end up needing endoscopic reintervention (E-RI) for recurrent biliary obstruction. To achieve a successful E-RI, it is necessary to understand the various findings regarding E-RI in MBO cases reported to date. Therefore, in this review, we focus on E-RI for ERBD of distal MBO, ERBD of hilar MBO, and EUS-BD. To plan an appropriate E-RI strategy for biliary stent occlusion for MBO, the following must be considered on a case-by-case basis: the urgency of the drainage, the cause of the occlusion, the original route of drainage (PTBD/ERBD/EUS-BD), the initial stent used (plastic stent or self-expandable metallic stent), and in the case of self-expandable metallic stents, the type used (fully covered or uncovered). Regardless of the original method of stent placement, if the inflammation caused by obstructive cholangitis is severe and/or the patient is in shock, PTBD should be considered as the first choice. Finally, it is important to keep in mind that in many cases, performing E-RI will be difficult.

The double-guidewire method has been increasingly used in endoscopic procedures for biliary and pancreatic diseases in recent years, including endoscopic retrograde cholangiopancreatography and endoscopic ultrasonography-related procedures. In addition, double-lumen catheters with uneven distal and proximal lumen openings have been introduced, making it possible to easily create a double-guidewire situation, and the usefulness of the double-guidewire technique using uneven double-lumen cannulas has been widely reported. Although the advantages of using two guidewires depend on the particular situation and the appropriate use of the two guidewires, deepening the knowledge of the double-guidewire method will contribute greatly to troubleshooting in daily practice. In this review, the usefulness of the double-guidewire technique is discussed with respect to two main areas: selective insertion of guidewires and devices and biliary cannulation.

Malignant hilar biliary obstruction (MHO), an aggressive perihilar biliary obstruction caused by cholangiocarcinoma, gallbladder cancer, or other metastatic malignancies, has a poor prognosis. Surgical resection is the only curative treatment for biliary malignancies. However, the majority of patients with MHO cannot undergo surgery on presentation because of an advanced inoperable state or a poor performance state due to old age or comorbid diseases. Therefore, palliative biliary drainage is mandatory to improve symptomatic jaundice and the quality of life. Among the drainage methods, endoscopic biliary drainage is the current standard for palliation of unresectable advanced MHO. In addition, combined with endoscopic drainage, additional local ablation therapies, such as photodynamic therapy or radiofrequency ablation (RFA), have been introduced to prolong stent patency and survival. Currently, RFA is commonly used as palliative therapy, even for advanced MHO. This literature review summarizes recent studies on RFA for advanced MHO.

No abstract available.
Constriction, Pathologic ; Pancreatic Ducts ; Pancreatic Neoplasms

Inflammatory bowel disease (IBD), with its 2 subtypes, Crohn’s disease and ulcerative colitis, is a complex chronic condition. A precise definition of disease activity and appropriate drug management greatly improve the clinical course while minimizing the risk or cost. Artificial intelligence (AI) has been used in several medical diseases or situations. Herein, we provide an overview of AI for endoscopy in IBD. We discuss how AI can improve clinical practice and how some components have already begun to shape our knowledge. There may be a time when we can use AI in clinical practice. As AI systems contribute to the exact diagnosis and treatment of human disease, we should continue to learn best practices in health care in the field of IBD.

Tacrolimus is a calcineurin inhibitor used for the treatment of corticosteroid-refractory ulcerative colitis (UC). Two randomized controlled trials and a number of retrospective studies have assessed the therapeutic effect of tacrolimus in UC patients. These studies showed that tacrolimus has excellent short-term efficacy in corticosteroid-refractory patients, with the rates of clinical response ranging from 61% to 96%. However, the long-term prognosis of patients treated with tacrolimus is disappointing, and almost 50% of patients eventually underwent colectomy in long-term follow-up. Tacrolimus can achieve mucosal healing in 40-50% of patients, and this is associated with a favorable long-term prognosis. Anti-tumor necrosis factor (TNF)-alpha antibodies are another therapeutic option in corticosteroid-refractory patients. A prospective head-to-head comparative study of tacrolimus and infliximab is currently being performed to determine which treatment is more effective in corticosteroid-refractory patients. Several retrospective studies have demonstrated that switching between tacrolimus and anti-TNF-alpha antibody therapy was effective in patients who were refractory to one of the treatments. Most adverse events of tacrolimus are mild; however, opportunistic infections, especially pneumocystis pneumonia, are the most important adverse events, and these should be carefully considered during treatment. Several issues on tacrolimus treatment in UC patients remain unsolved (e.g., use of tacrolimus as remission maintenance therapy). Further controlled studies are needed to optimize the use of tacrolimus for the treatment of UC.
Antibodies ; Calcineurin ; Colectomy ; Colitis, Ulcerative* ; Cyclosporine ; Follow-Up Studies ; Humans ; Infliximab ; Necrosis ; Opportunistic Infections ; Pneumonia, Pneumocystis ; Prognosis ; Tacrolimus*

For the control of Crohn's disease (CD) a thorough assessment of the small intestine is essential; several modalities may be utilized, with cross-sectional imaging being important. Magnetic resonance (MR) enterography, i.e., MRE is recommended as a modality with the highest accuracy for CD lesions. MRE and MR enteroclysis are the two methods performed following distension of the small intestine. MRE has sensitivity and specificity comparable to computed tomography enterography (CTE); although images obtained using MRE are less clear compared with CTE, MRE does not expose the patient to radiation and is superior for soft-tissue contrast. Furthermore, it can assess not only static but also dynamic and functional imaging and reveals signs of CD, such as abscess, comb sign, fat edema, fistula, lymph node enhancement, less motility, mucosal lesions, stricture, and wall enhancement. Several indices of inflammatory changes and intestinal damage have been proposed for objective evaluation. Recently, diffusion-weighted imaging has been proposed, which does not need bowel preparation and contrast enhancement. Comprehension of the characteristics of MRE and other modalities is important for better management of CD.
Abscess ; Animals ; Capsule Endoscopy ; Comb and Wattles ; Comprehension ; Constriction, Pathologic ; Crohn Disease* ; Diffusion Magnetic Resonance Imaging ; Edema ; Fistula ; Humans ; Intestine, Small* ; Lymph Nodes ; Sensitivity and Specificity