My urethral opening is the same size as my vaginal opening. i use a mitrofanoff. (i can't urinate through my urethra) could this be involved?

What is the question: I know what Mitrofanoff is, I am a little confused about urethral size and vaginal size, but I can understand it. I did not know what this could be involved in what? If this a follow up question, i did not get the first part. You can ask the question again with some more clarity of what you really want. sorry some of my colleague might have a better understanding, and a better answer.