Does the Amount of Tissue included in the Hemoclip used for FI correlate with the Degree of Post-vasectomy Discomfort?

Doug Stein
I have always wondered about this question. Sometimes clips or suture ties are placed on sheath only, and sometimes vessels are included, especially if those vessels are bleeding or look like they might bleed. Nerves travel with vessels, and brisk application of a clip can cause a jolt of discomfort during an otherwise painfree vasectomy. Sometimes the sheath tissue in the hemostat or pickups is "torn back" in an effort to include the posterior aspect of the sheath and achieve "true" FI.
If one simply closes the exposed sheath over the abdominal (prostatic) end, are we really achieving true fascial interposition? The photos and diagram show that while sheath/fascia is interposed between the very ends of both arms, there is no sheath between the abdominal end and the body of the testicular arm.
Michel has emphasized the importance of this "tearback" maneuver to bring the posterior aspect of the sheath into the clip or suture tie.
This rather amateur diagram illustrates the point. More complete FI should result in a lower failure rate. Failures (whether early or late) are VERY disconcerting (even if only 1 in 3000). But more complete FI invariably requires that more tissue be included in the hemoclip or suture. Does this result in more post-vasectomy discomfort? We decided to find out.
When my med-student daughter Alison was home, she took pictures of a series of vasectomies, we categorized each side according to the amount of tissue in the clips, then she called patients on post-vasectomy days 1, 4, and 7, inquiring about pain on each side on a scale of 1-10. 37 patients (74 vasectomy sides) were included in the study. She reached 32 patients on day 1, 25 patients on day 4, and 27 patients on day 10.
Category 1: Little tissue in clip, never tearback
Category 2 "No": Moderate tissue in clip, no tearback
Category 2 "Yes": Moderate tissue in clip, with tearback
Category 3: Much tissue in clip, always with tearback
This was very subjective as you can see in the montages of photos below, and it may look like there is some overlap between categories. Some patients had a 1 on one side and a 3 on the other side, depending on the number, size, fragility, and clinginess of vessels running alongside each vas.
The results showed that there was no correlation between the amount of tissue included in the hemoclip and the degree or duration of post-vasectomy discomfort.

In fact, if anything, the sides categorized as 1s seemed to be a bit more uncomfortable than the sides categorized as 3s on all days of follow-up.

The sides categorized as 2s seemed to be just as uncomfortable on day 4 as they were on day 1, but this may be a sampling error as a result of different patients being available for follow-up on different days. Only 19 patients were reached on all 3 follow-up days.