From the Guidelines
A gastroenterologist can typically reach up to 100 cm from the angle of Treitz into the small bowel during a standard EGD, but specialized techniques like device-assisted enteroscopy can reach deeper. When performing an esophagogastroduodenoscopy (EGD), the depth of insertion into the small bowel is generally limited by anatomical constraints, such as the ligament of Treitz. According to the most recent guideline evidence 1, conventional push enteroscopy is intended to access only the proximal small bowel, with a median insertion typically not exceeding 100 cm from the angle of Treitz. Key points to consider when evaluating the depth of insertion during an EGD include:
- Standard adult endoscopes are about 100-110 cm in length, but anatomical angles and the fixed attachment of the duodenum at the ligament of Treitz generally limit deeper advancement 1.
- The second portion of the duodenum contains important landmarks, including the major duodenal papilla (ampulla of Vater) where the common bile and pancreatic ducts enter.
- Specialized techniques, such as device-assisted enteroscopy, can potentially examine the entire small bowel, but these procedures are not considered standard EGDs and are typically performed for specific indications such as obscure gastrointestinal bleeding, suspected small bowel tumors, or Crohn's disease 1. It's worth noting that the AGA clinical practice update on high-quality upper endoscopy 1 provides best practice advice on how to perform a high-quality upper endoscopic examination, but it does not specifically address the depth of insertion into the small bowel during an EGD.
From the Research
Depth of Insertion with EGD
- The depth of insertion with an EGD (Esophagogastroduodenoscopy) is generally limited to the proximal jejunum, which is the first part of the small bowel 2.
- Push enteroscopy (PE) is a technique that can be used to examine the proximal jejunum, but it is not suitable for deep small bowel endoscopy 2.
- For deeper small bowel endoscopy, other techniques such as double-balloon enteroscopy (DBE), single-balloon enteroscopy (SBE), and spiral enteroscopy (SE) are required 2, 3.
Comparison of Techniques
- DBE is considered the gold standard for deep small bowel endoscopy, providing the highest rates of complete enteroscopy 2.
- SBE and SE are also effective techniques, but may have slightly lower rates of complete enteroscopy compared to DBE 2, 4.
- Motorized spiral enteroscopy (MSE) has been shown to enable deeper and total small bowel evaluation compared to SBE in suspected Crohn's disease, but has been withdrawn from the market due to safety concerns 3, 4.
Use of Colonoscope
- A colonoscope can be used for distal duodenal stent placement in patients with malignant obstruction, and has been shown to be effective and safe in this setting 5.
- The use of a colonoscope can overcome the limitations of a therapeutic gastroscope, such as reach and flexibility, and can provide good endoscopic stiffness to avoid looping in the stomach 5.