Welcome to ASGE Video Tip of the Week. This week's topic is Submucosal Injection for EMR. In today's video, we'll cover various submucosal injection agents, especially the popular ones in the US, and go over a few technical tips on how to perform an effective injection through some videos. A recent Multi-Society Polypectomy Guideline reviews various submucosal injection agents available worldwide, and I highly recommend reading it for this topic. A table from that guideline is shown here. We will go a little bit deeper into these four agents in the US, three of which are FDA approved. Elavu is the first FDA cleared agent for submucosal injection, hence is the only one with the data available which is against saline. Dr. Repicci's randomized trial showed higher on-block resection rates and less fragments in piecemeal resections. It's composed of a variety of polymers to provide viscous injection. The dye used is methylene blue. It comes in a box of five 10ml ampoules that need to be filled in a syringe prior to EMR. Orize gel has a proprietary blend of viscous agents with a food coloring blue dye. It comes in a box of two pre-filled 10ml syringes. Everlift is the newest FDA cleared agent. Hydroxyethylacellulose is the main viscous agent, and the dye used is methylene blue. There are options of 5ml or 10ml pre-filled syringes. Hydroxyethyl starch is a colloidal IV fluid that can be repurposed as a viscous submucosal injection fluid, typically packaged as a 6% hydroxyethyl starch and saline as a 500ml bag. It has a long track record for use as a submucosal injection agent. It's readily available in most hospitals. It's inexpensive, especially when used in large volume like in ESDs or for multiple EMRs in a single day. Let's review some tips on submucosal injection with the help of a few videos. The first lesion shown here is a 3cm LSD granular hepatic flexure polyp with tattoos surrounding the polyp on the same ball. In this video, the submucosal injection has begun at the odor side of the lesion. Coordination with tech is very important to avoid deep or superficial injection. Once the submucosal plane is entered, the tip of the needle is deflected to direct fluid to achieve the desired shape of the elevation rather than a flat spread of injectate within the submucosa. Subsequent injections are typically made at the ends of the expanded submucosa, but still using the dynamic injection principles like before. Recognize a mucosal injection like promptly and stop. In all such cases, further submucosal injection or EMR is not impaired. The second lesion is like the first. Tattoo again near the lesion. This is a residual or recurrent LSD granular polyp with a scar at the oral end of the lesion, but the lesion lifts reasonably well. Initial injection at the oral end of the lesion was ineffective with injectate not penetrating the space under the polyp. Choosing a different area resulted in effective submucosal injection under the polyp. Notice the needle tip deflection to allow more fluid to enter the space under the polyp and create the desired shape of the polyp. Similar demonstration now towards the anal side of the lesion with tip deflection towards the lumen to create the desired shape of the elevated polyp. Unlike saline, the newer more viscous fluids helps the submucosal lift to stay in the same shape longer. To summarize this video, know your submucosal injection agents that are available to you. Each has its own advantages and its limitations. Cost may be a factor as well. More agents are likely to be available given the recent trend. Get into your submucosal plane. Communication and coordination with your assistant is crucial for this step. Practice dynamic injection. Needle tip deflection once in the submucosa is critical to achieve the lift and the desired shape of the lift. Regulating wall tension of the colon with suction or insufflation aids in achieving the desired lift as well as in the resection of the lesion. And this is your video tip of the week.

submucosal injection

EMR

injection agents

Multi-Society Polypectomy Guideline

dynamic injection techniques