On left, it is possible to drive back the pleural injecting
local anaesthetic or physiological salt solution during the progression of
the needle wich increases space between pleura and vertebra.
On right, bilateral malposition of the needles with a needle crossing
the diaphragmatic pillar (long line) and the other through the renal capsula.
The CT scan easily makes it possible to rectify the position of those.

On left, the left needle is in good position but the right one is
still too ahead; Image of right, the two needles seem in good position
but an injection test of contrast is essential.

The injection of contrast shows a good diffusion behind the
diaphragmatic pillars which allows bilateral alcoholization.