A technique has been developed to complete the processing of fine needle aspiration biopsy material of deep and/or superficial organs: a method of collection and "prefixation staining" allowing visualisation of very small coherent fragments (microfragments) obtained by fine needle aspiration biopsy and which can consequently be submitted to histological examination. This method optimises CT-guided fine needle aspiration biopsies which, up until now, were only submitted to cytological examination (smears on slides, cell pellets, concentration and cytocentrifugation). Histological analysis of microfragments of 35 aspiration biopsies of various organs (pancreas, liver, adrenals, retroperitoneal nodes, paravertebral and mediastinal masses, etc.) was contributive in 71.4% of cases (25/35). In conclusion, the combination of cytological and microfragment inclusion techniques increased the diagnostic yield to 80% of cases.