The extraction method is to extract Ogilvy from the body with a needle, but Ogilvy will be free after injection into the human body, and will leave the original injection site after free diffusion. The extraction method is blind, and it is difficult to locate the distribution of Ogilvy and take it out. It is likely that only a part of Ogilvy was taken out, leaving a lot of Ogilvy, which led to the failure of taking out.

Effective removal methods should be able to expand the surgical field of vision as much as possible and locate the distribution of Ogilvy. Excellent technology combined with the use of 3D endoscope can locate the distribution of Ogilvy in the whole process of direct vision, effectively avoid blood vessels and nerves, and remove Ogilvy without damaging normal tissues.