Comments on the article 'A single injection, multisegmental paravertebral block-extension of somatosensory and sympathetic block in volunteers,' written by Saito et al. which appeared in a 2001 issue of the journal 'Acta Anaesthesiologica Scandinavica.' Performance of the injection under radiological control; Ability of the anesthetists in identifying intravertebral space levels based on anatomical landmarks.