For trials, I think both unilateral and bilateral entry are feasible and can be efficient. In my hands, unilateral is much faster because the second needle is essentially following the fluoro path created by the first needle, you have a clear idea of what the depth and angle is, so after few second and 1-2 shots you can hook up your LOR syringe. It feels faster and easier to me, but that may simply reflect how I was trained and what I have done for years. For a trial, I think whichever approach is safe, reproducible, and works well for the operator is reasonable.
The reason I’m reviving this thread is the implant-side discussion, particularly incision planning. One approach I would strongly argue against is bilateral incisions. Aside from being more invasive than I think this procedure needs to be, in many patients those incisions would end up uncomfortably close together. That creates a narrow intervening skin bridge and a problem that seems entirely avoidable. If there were any wound breakdown or bridge compromise, it would be difficult to defend from a basic surgical-planning standpoint. To be fair, one could argue that 2 cm between incisions is adequate, and there is some ankle surgery literature that can be cited in support of that. But that feels like a pretty thin reed to lean on, especially when the whole issue is avoidable. Also, the bigger issue may be what this creates for any future spine exposure at that level. A midline incision between two prior paramedian incisions only 2–3 cm apart becomes problematic. The surgeon may need to ellipse out the intervening skin or accept a higher-risk wound situation and go in-between. My spine colleagues would likely have strong opinions about inheriting that incision pattern.
Lastly, SgtThunderfistMD’s approach aligns pretty closely with what I do. It is easy, safe, and efficient: 2–3 cm midline incision, dissect, weitlaner or army to the side, then unilateral epidural access. No fishing expedition for leads, no creative tunneling, and no other intraoperative gymnastics. I have also found unilateral leads easier to explant. We have a local pain physician who uses a bilateral approach with a transverse incision — ouch — and explanting those leads always seems to take longer, require more aggressive tissue manipulation, and involve a little more swearing in the OR. Obviously, individual mileage may vary, but from the standpoint of future revisions and explants, I would much rather inherit a clean one incision and unilateral access than incisions and placement that turns the revision into an arts-and-crafts project.