The authors investigated the possibility of radical removal of adenomas of the pituitary (AH), while preserving remnants of pituitary tissue, in 23 patients with primarily operated hyperfunctional AH producing PRL (14 patients), STH (8 patients) and ACTH (1 patient). Normalization of the pathologically elevated hormone level was achieved by the transsphenoid operation without supplementary treatment in 13 of 16 patients with defined and in 3 of 7 patients with invasively growing AH (PRL in 10, STH in 5 and ACTH in one patient), i.e. in 69.5% Identification and preservation of remnants of the pituitary was possible in 20 patients (in all 16 with defined and in 4 of 7 with invasive AH); 17 of them (73.9%) do not need hormonal substitution. Radical and at the same time selective adenomectomy was achieved in 14 patients (60.9%) incl. three patients with invasively growing tumours. The improved activity of the pituitary is manifested clinically after successful operation in particular in young patients by improved gonadal function.