Hello jalrein.
Thank you for your post and for the photos which make it a bit clearer as to what you are referring to.
Once or twice I have had my stoma suddenly expand and touch the wafer's edge. The last time this happened the wafer cut into the stoma and made it bleed profusely. Once it healed up I was left with similar darker red lines. I put this down to the way the stoma heals itself after injury. So, from my perspective, there is nothing much to worry about.
However, as with anything stoma related, if you are concerned about it, then a visit to the stoma nurse would be a wise course of action. I always think that stoma nurses are a useful bank of knowledge and information, so the more people that go and show them things, the more experienced they become to pass on their knowledge to others in the future.
In my case, on this occasion, the stoma nurse did not seem too concerned about what looked like someone had slit my stoma's throat with a razor She reassured me that, given time and TLC, my stoma would heal and not become a problem. This is precisely how it has turned out - apart from the residue of a thin red line, which presumably is the equivalent of a scar on normal skin.
Interestingly, these lines on my stoma have all been underneath where I cannot see them without a mirror . Hence, they don't get examined very often and I tend to forget about them. I am not sure how I would feel if they were constantly in view on the top of the stoma where they would regularly remind me that things were not quite as I expected.
Best wishes
Bill
Best wishes
Bill