For aorticorenal plexus the ideal protocol is the same as any nerve: - 10 minute freeze - 3 minute passive thaw - 3 minute freeze - 3 minute passive thaws It is useful to hold the needles physically in place when you're thawing, because the aortic side will thaw very quickly, and the needle might move depending on the probe used you might start counting the 10 minutes once you have reached a certain goal, amount of ice, because many probes have trouble achieving ice in this region, some people are moving to a single 12 minute freeze for nerves, but the overall concept is long freezes (and passive thaws to avoid osmotic disruption of the nerve which causes a more disorganized neurolysis.) https://pubs.rsna.org/doi/full/10.1148/rg.220082