The editorial team of Leading Medicine Guide was able to learn more about modern techniques in interventional endoscopy in a conversation with Prof. Dr. Weismüller.
Modern techniques in interventional endoscopy are revolutionizing the diagnosis and treatment of diseases of the digestive tract. By using innovative endoscopic methods, numerous conditions can be treated in a minimally invasive, precise, and gentle manner. These advanced procedures make it possible, for example, to selectively remove tumors, treat strictures, place stents, and perform preoperative diagnostics and therapy in complex clinical conditions.
Thanks to continuous technological advances, interventional endoscopic methods not only improve treatment outcomes, but also significantly enhance patients' quality of life. They therefore represent a major pillar of modern medicine, in which interdisciplinary collaboration and the use of the latest technologies play a key role.
„Many people primarily associate the term gastroenterologist with upper and lower endoscopy. In fact, around 30 years ago endoscopy was mainly a diagnostic procedure – and in the public perception, this is often still the case. In office-based practices, diagnostic endoscopy remains the main focus, even if small polyps are removed there or tissue samples (biopsies) are taken.
In the hospital setting, however, the situation has changed considerably. Due to the technical innovations of recent years, the focus has clearly shifted from pure diagnostics toward interventional, that is, therapeutic procedures. Today, gastroenterologists treat not only the esophagus, stomach, duodenum, small and large intestine, but also the liver, bile ducts, and pancreas. In doing so, they work closely with their colleagues in visceral surgery – that is, abdominal surgery.
This close collaboration has led to a modern understanding of what is known as visceral medicine: Gastroenterology and surgery approach the same diseases from different perspectives in order to jointly identify the best possible individualized treatment for each patient.
While the miniaturization of techniques has brought major progress in surgery, modern endoscopes now make it possible in gastroenterology to perform procedures from the inside – without any abdominal incision at all“, explains Prof. Dr. Weismüller at the beginning of our conversation and continues:
„The advantages of these minimally invasive therapies are considerable: In early-stage tumors, for example, lesions can be removed endoscopically without the need for surgery. The affected organ is preserved, such as the rectum or the esophagus – a crucial factor for patients' quality of life. At the same time, it is important to know the limitations of these techniques.
For this reason, all patients are discussed in an interdisciplinary setting – in tumor boards or dedicated case conferences – in order to determine the best individual therapy. Modern endoscopic methods offer the great advantage of reduced trauma, organ preservation, and a significantly shorter length of stay in the hospital“.
In recent years, numerous technical innovations have significantly driven the development of modern interventional endoscopy and broadened its range of applications.
One of the most important developments is the improvement of the endoscopes themselves, in particular the introduction of high-resolution 4K and even 8K cameras, which enable precise visualization of even the smallest structures and almost microscopic details in the digestive tract. This high-resolution imaging dramatically increases the accuracy of both diagnosis and therapy.
„Thirty to forty years ago, many procedures in the gastrointestinal tract were still performed as open surgeries. Conditions such as early carcinomas or large adenomas had to be removed surgically, which usually meant large abdominal incisions, longer wound-healing times, a higher risk of complications, and significant impairments in quality of life.
With the dawn of laparoscopic surgery, this changed fundamentally: Today, both in surgery and in gastroenterology, most procedures are done minimally invasively – using small instruments, sometimes even robotic systems, or via the natural access through the digestive tract. The technical development of these procedures gained real momentum at the end of the 1990s, particularly with the introduction of endoscopic ultrasound (endosonography).
This made it possible to treat diseases transluminally, that is, through the stomach wall – for example in the case of infected collections after pancreatitis. Since then, innovation in endoscopy has brought new advances virtually every year: improved clipping techniques, specialized metal stents, more precise instruments, and innovative endoscopic tools continuously expand the therapeutic possibilities“, explains Prof. Dr. Weismüller.
A true milestone was the development of so-called Lumen apposing Metal Stents (LAMS) – metal stents designed to connect two hollow structures with each other.
A lumen-apposing metal stent has been placed through the stomach wall into an infected pancreatic pseudocyst.
Lumen apposing Metal Stents (LAMS) are specialized metal stents used to connect two hollow organs or cavities. They are primarily used in interventional endoscopy, for example in pancreatic necrosis or gallbladder inflammation, and can be placed minimally invasively via an endoscope without the need for major surgery. They allow effective drainage of infected fluid or advancement of the endoscope into an infected cavity in order to remove necrotic and infected tissue. Procedures that previously required a classic operation with an abdominal incision can now be performed from the inside with far less damage to healthy structures.
Prof. Dr. Weismüller illustrates this as follows: „With their help, for example, necroses following severe pancreatitis can now be treated in a gentle manner. Under endosonographic guidance, the stent is placed from the stomach into the necrotic cavity so that the dead tissue can be removed endoscopically from the inside. In this way, the inflammation can resolve – whereas in the past a high-risk operation was often necessary. These stents are also used in acute cholecystitis, particularly in patients who are too ill or too frail to undergo surgery.
In such cases, the gallbladder can be drained internally, allowing the pus to flow out and the inflammation to subside. At the same time, endoscopes have become finer and more powerful. Modern devices, only 3 mm thin, now allow direct visualization of the bile ducts or pancreatic duct and make it possible to detect even the smallest changes and treat them in a targeted, minimally invasive fashion – a difference much like that between the camera of a modern smartphone and a model from 20 years ago.
Thanks to this improved image quality, we can plan interventions more precisely today and treat more selectively. This is increasingly supported by artificial intelligence, which serves as an assistive tool in detecting and classifying lesions. In recent years, closure techniques such as clips or suturing systems have also been further developed, so that the access route or wound surface can be closed securely and gently after an endoscopic procedure“.
The use of interventional endoscopic methods has proven to be highly effective, based on solid evidence, in a wide range of clinical conditions. These include, in particular, the treatment of precancerous and cancerous lesions in the stomach, intestine, and esophagus, as well as functional disorders such as achalasia.
„In minimally invasive endoscopic procedures, secure closure of the access route is crucial. Modern closure techniques, such as improved clip systems, now make it possible to reliably close the openings that are intentionally created for the procedure. These technical innovations have greatly expanded the possibilities of endoscopy.
Nevertheless, these techniques also have their limitations, especially in oncology. As long as a tumor is confined to the top mucosal layer, it can be removed endoscopically – this is what we refer to as an early carcinoma. Once the tumor has invaded deeper into the submucosa (a layer of the gastrointestinal wall), there is a risk that it has already formed lymph node metastases. These cannot be addressed endoscopically, which is why surgical removal of the lymph nodes becomes necessary in such cases.
In practice, this means that after an endoscopic submucosal dissection (ESD), the removed tissue is examined by pathology. If an increased risk of metastasis is identified, surgery is required as a second step – nowadays often already performed minimally invasively with robotic systems, which help reduce the surgical trauma for the patient. This interplay between endoscopy and surgery is a prime example of the modern concept of visceral medicine: Both disciplines work hand in hand to find the gentlest yet most effective treatment for each patient.
In addition to medical limitations, there are also individual factors that influence the use of endoscopic procedures – such as age or preexisting conditions. In very elderly patients, the risk of an intervention may outweigh its potential benefit. At the same time, there are very old individuals who are still biologically fit and benefit from minimally invasive treatment. There is therefore no rigid age limit – what ultimately matters is the overall condition and quality of life of each individual patient“, explains Prof. Dr. Weismüller.
The submucosa is a layer of the intestinal and stomach wall located directly beneath the mucosa. It consists of connective tissue, blood and lymph vessels, as well as nerves, and supplies the mucosa with nutrients. During endoscopic procedures, this layer is often expanded by injecting saline so that the intervention can be carried out in this boundary layer, separating tumor tissue from healthy tissue.
Today, gastroenterology encompasses far more than just upper and lower endoscopy – it deals with the entire digestive tract, including the liver, bile ducts, and pancreas, and covers a wide spectrum of diseases.
„In gastroenterology, many different areas benefit from minimally invasive endoscopic procedures. These include, among others, endoscopic mucosal resection, endoscopic submucosal dissection (see box), endoscopic full-thickness resection, in which all layers of the intestinal wall are precisely removed, as well as procedures on the esophagus such as peroral endoscopic myotomy (POEM) for achalasia (a rare disorder of the lower esophageal sphincter). In addition, modern thin endoscopes (cholangioscopes) now allow procedures in the bile ducts and pancreatic duct, for example to fragment stones or treat tumors minimally invasively. The technical advances in recent years have been enormous: Optics have improved markedly, and image quality now enables a precise assessment of whether lesions are benign or malignant, without always requiring biopsies.
Artificial intelligence is increasingly being used in endoscopy to support diagnosis and optimize therapy planning“, explains Prof. Dr. Weismüller.
Peroral endoscopic myotomy (POEM) is a minimally invasive procedure for the treatment of achalasia. A small tunnel-like access is created in the mucosa of the esophagus in order to selectively cut the thickened and spasmodic muscle fibers at the lower end of the esophagus. This allows the esophagus to open again and enables food to pass more easily into the stomach. The advantage: No external incision is required; the treatment is performed entirely from the inside and is gentler than conventional surgery.
In achalasia, an endoscopic tunnel is first created in the esophageal wall (A). Under the intact mucosal layer, the esophageal muscle is then cut using a tiny endoscopic knife (B). After complete division of the muscle layer in the area of the lower esophageal sphincter (C), the tunnel entry is closed with endoscopic clips (D).
Although advanced endoscopic procedures are generally safe and effective, they are still associated with certain risks, despite all technical innovations. While rare, complications such as bleeding, infections, perforations, and inadvertent injury to surrounding structures can occur in individual cases.
Prof. Dr. Weismüller explains: „In minimally invasive endoscopic and interventional procedures, there are specific risks and complications that depend heavily on the particular intervention. Overall, these procedures are less risky than major open operations; however, the risk of complications increases with the extent of the intervention. Bleeding is particularly relevant, as many blood vessels are present in the field of surgery in transvisceral procedures.
Infections can also occur if a procedure passes through non-sterile areas into sterile structures such as the bile ducts; this risk is addressed prophylactically with antibiotic therapy. In addition, there are the general risks associated with general anesthesia, which is required for longer procedures. Minimally invasive techniques, however, clearly offer the advantage of less surgical trauma, shorter hospital stays, and the possibility of preserving the affected organs“.
In principle, a minimally invasive endoscopic procedure is significantly more advantageous for the postoperative period, particularly in terms of pain and recovery time.
„Because access is achieved without an external incision, many patients hardly notice after the procedure that an intervention has taken place, and they usually experience only minor discomfort, depending on the area treated. To ensure safety and enable rapid countermeasures in the event of complications, patients are typically monitored in the hospital for one to two days, undergo regular lab tests, and are often given prophylactic antibiotics.
The length of stay depends heavily on the procedure: For elective interventions such as endoscopic submucosal dissection (ESD), one to two days are often sufficient, whereas more complex procedures such as POEM require around four days. Acute emergencies, for example patients with infected necroses, remain in the hospital for a longer period accordingly. Overall, the duration of hospitalization varies depending on the intervention, risk profile, and general health status, with planned procedures involving the esophagus or colon usually requiring a much shorter hospital stay than complex emergency situations“, explains Prof. Dr. Weismüller.
A tumor at the gastric inlet (A) is dissected from the stomach wall during an upper endoscopy using a millimeter-sized endoscopic knife (B). The remaining wound defect (C) has completely healed after a few weeks (D).
Endoscopic submucosal dissection (ESD) is a minimally invasive procedure in which precancerous lesions or early carcinomas in the stomach, intestine, or esophagus are removed en bloc with the aid of an endoscope. Using a fine needle knife, the diseased mucosa is separated from the underlying healthy muscle layer so that the wound can subsequently heal and the organ can be preserved.
Ongoing technological advances – such as the integration of highly precise imaging systems and computer-assisted guidance, as well as modern anesthetic techniques – further increase safety. In addition, complex procedures are always preceded by thorough patient counseling, a careful preoperative risk assessment, and close monitoring during and after the intervention.
Prof. Dr. Weismüller emphasizes: „Endoscopic and minimally invasive procedures are now offered at many large hospitals in Germany, although not yet universally available everywhere. Development in this field is highly dynamic: At every conference, new innovations, techniques, and procedures are presented that continue to push the boundaries of minimally invasive treatment options and open up new possibilities year after year.
For patients, it is especially important to provide all existing medical records, including previous endoscopic examinations or imaging studies, so that the team has a complete overview of the situation. At Vivantes, treatment is characterized by extremely close interdisciplinary collaboration between gastroenterology and surgery. This ensures that, if surgery becomes necessary, action can be taken immediately and patient care continues seamlessly.
Likewise, the surgical colleagues rely on endoscopic expertise when complex interventions need to be solved minimally invasively. Close cooperation, the provision of comprehensive prior findings, and clear communication enable efficient planning and execution of procedures. Therefore, patient inquiries should be as detailed as possible – not just two or three sentences – in order to ensure smooth processes and the best possible individualized care“ and he concludes:
„Across Germany, there are many excellent endoscopists, and it is not necessary to come to Berlin for every treatment. However, for the northwest of Berlin and the surrounding communities in Brandenburg, we are an excellent point of contact, as we can offer the full spectrum of minimally invasive procedures.
What is particularly important here is close interdisciplinary collaboration: In the past, internal medicine and surgery were viewed separately; today we work hand in hand with abdominal surgery and other specialties to provide patients with the best possible and holistic care. This interplay is central to ensuring optimal treatment“.
Professor Dr. Weismüller, thank you very much for your detailed description of endoscopic procedures!
- Prof. Dr. Tobias Weismüller is Head of the Departments of Gastroenterology and Hepatology at Vivantes Humboldt-Klinikum and Vivantes Klinikum Spandau in Berlin.
- Specialist in diseases of the digestive tract, liver, bile ducts, and pancreas.
- Many years of experience and extensive expertise in diagnostics, endoscopy, and interventional therapy.
- Focus areas: Procedures on the bile ducts and pancreas, treatment of esophageal diseases such as achalasia or diverticula, and minimally invasive tumor removal in the esophagus, stomach, and intestine.
- Relies on innovative endoscopic techniques for particularly gentle and precise treatments.
- Actively involved in interdisciplinary collaboration with oncology, surgery, and radiology.
- Member of several national and international professional societies.
- Academic work at leading university hospitals such as Hannover Medical School and University Hospital Bonn.
- Committed to the training and education of young physicians.
- Author of more than 100 scientific articles, books, and presentations.
- Stands for high medical quality, modern techniques, and empathetic patient care.
