Scanning electron microscopy of osteoid osteoma.

We have examined the organic components of the nidus of an osteoid osteoma in 4 patients using scanning electron microscopy. Different organisation of the osteoblastic cells and of the fibrous structures of the osteoid matrix in different zones was demonstrated. These findings indicated a greater degree of immaturity in the centre, as compared with the peripheral area where the process of differentiation was more evident.