Welcome to our latest podcast episode, where we dive deep into the innovative and increasingly popular technique known as Water Assisted-Colonoscopy, or WAC, also referred to as Hydrocolonoscopy. This method has been garnering attention for its substantial benefits to both endoscopists and patients in the realm of colonoscopy procedures.

To begin with, let's understand the concept and application of WAC. This technique involves the use of water instead of traditional air or gas for the insertion phase of a colonoscopy. The core idea here is to utilize water's natural properties to aid in the colonoscopy process. Studies have shown that WAC can significantly reduce the pain associated with colonoscopy. This is especially beneficial in challenging cases, where the colonoscope has to navigate through complex bends and loops in the colon. WAC aids in straightening out the colon and mitigating angulations.

The benefits of WAC arise from two principal mechanisms. Firstly, the use of water exerts a gravitational effect which reduces colonic elongation. This, in turn, minimizes loop formation, which is a common cause of discomfort during the procedure. Additionally, this method reduces the requirement for sedation, making the process safer and more comfortable for patients.

Secondly, the technique of water irrigation enhances the visibility of the mucosal surface. This is crucial for detecting adenomas, which are precancerous growths in the colon. By improving adenoma detection rates (ADR), WAC plays a pivotal role in colorectal cancer prevention.

When we compare WAC with traditional methods like air insufflation, the benefits become even more evident. Both water immersion and water exchange methods have been shown to significantly reduce the pain experienced during colonoscopies. An important aspect to note here is that the use of water does not compromise other facets of the colonoscopy. For instance, the duration of the procedure remains unchanged, addressing a common concern among patients and medical professionals.

In our practice, we have embraced a modified version of WAC, which we refer to as "partial" WAC. This approach involves a combination of water and CO2 use during the colonoscopy. Here, water is employed for its benefits in traversing tight angulations, preventing colon elongation, and cleaning the mucosal surface. Concurrently, CO2 is used to open up the lumen and flatten the folds, which is essential for efficient polyp detection. The integration of modern colonoscopes with waterjets facilitates this hybrid technique, allowing for seamless suction and liberal use of water, thereby enhancing the overall quality of the colonoscopy.

Moreover, the extensive use of water is critical for cleaning the mucosal surface during a colonoscopy. It helps in removing any debris, thereby improving the visibility and detection of colorectal adenomas. Water also plays a vital role in certain resection techniques, such as underwater endoscopic mucosal resection. It is equally important in cleaning the wound surface during and after procedures like polypectomy.

To sum up, water is not just an alternative for colon distention in colonoscopy; it's an essential component that significantly elevates the effectiveness of the procedure. Whether used as the primary method or in a dynamic, hybrid approach, WAC enhances patient comfort and potentially improves clinical outcomes. This advancement in colonoscopy practice not only makes the procedure more bearable for patients but also holds the promise of better preventive measures against colorectal cancer.