If you look at the top right picture you’ll notice that the method used for this vasectomy was a clip. You’ll also notice that the vas to the left of the clip is larger in diameter than the vas extending below the clip. This is because the larger diameter vas is coming from the testicle and is always larger to the pressure of the sperm produced. This is the area of the vas at the time of the reversal where fluid is checked for its character and the presence or absence of sperm or sperm parts. When the testicular end is cut you almost always see fluid emanate promptly.
This back pressure is what is felt to be responsible for post vasectomy pain syndrome. I have postulated in a previous post that the inflammatory changes around the spot of the vasectomy could also contribute to this syndrome and the pain.
Although not all urological microscopic surgeon remove the entire vasectomy site, I always do. I feel it is cleaner and may help with any pre-reversal symptom issues related to this area of healing/inflammation associated with the vasectomy.