[MR tomography of aneurysmal bone cyst].

The preoperative findings of magnetic resonance imaging (MRI) in six histology-proven aneurysmal bone cysts (ABC) are examined and compared with previous publications concerning MRI of ABC. The signal intensities differ considerably, and not all of our cases conform with the literature data. They can be summarised in three different subheadings: one form that is very inhomogeneous in T1- and T2-weighting, with fluid-fluid levels in the cystic spaces; one intermediate form without fluid-fluid levels, which is inhomogeneous only in T2-weighted images; and finally, an unusual form of ABC that has homogeneous low signal both in T1- and T2-weighting, and which has not been described in literature so far.