Mucosal plaque means that excess mucus has built up and turned into plaque (latin for plastic) so-named because it is very hard (much like the calcium plaque of the arteries). Using an enema only stimulates/forces peristalsis of the colon. The mucosal plaque is found in the small intestine after excess mucus has built up and hardened. So even if the peristalsis "reverberated" up to the small intestine (as can happen in a bowel movement or during a colonic), it cannot soften the buildup to release it.

Old buildup (mucosal plaque) needs to be softened by proper eating and certain types of fiber. This stuff is hard and took years to buildup so it takes time. This is why Colon Cleanse products usually contain psyllium fiber or Bentonite clay, because these substances can lay on this excess plaque and soften it over time. It can take 1 to 4 weeks on a program before you see any plaque leave your body. Many people may see plaque right away on their first cleanse because that plaque hasn't adhered to the rest, yet. (It may be only 4 month old buildup while the rest is older and older, therefore takes longer to soften.) Once you have been on a proper diet/colon cleansing program, then an enema or colonic would be more productive. I hope this helps.