Intra-operative detection of SLN
Intra-operatively, patients had 2 ml of blue dye (patent
blue V sodium 2.5%, Guerbet, UK) injected intra-dermally
around the previous biopsy scar or residual melanoma.
Once the relevant drainage basin was exposed, the SLN was
located using a hand held gamma probe (Neo2000, Neoprobe
Co, Dublin) and by visualising blue staining in the node
and afferent lymphatics. Those SLNs with the greatest
radioactivity and those stained blue were excised. Radioactivity
of the excised tissue was measured ex-vivo to
confirm the targeted node had been successfully removed.
Additional nodes measuring 10% or greater of the hottest
node were also excised. The surrounding tissues were systematically
probed to exclude any residual clinically relevant
nodes.