[Plain imaging of meningioma in NMR tomography--retrospective contrast optimization by image synthesis].

Synthetic images of the tumour region were computed in the case of ten meningiomas for the purpose of determining retrospectively pulse sequences and sequence parameters supplying an optimal contrast between tumour and adjacent tissue in plain imaging. It was found that best results were obtained via the partial saturation/spin-echo sequence with a long recovery time (TR approximately greater than 2,000 msec) and a long maximum echo delay (TE max approximately greater than 200 msec). A comparable contrast quality can be attained by using the inversion-recovery sequence with an inversion time T1 approximately 450 msec. Nevertheless, it was not possible in our study to identify two small meningiomas with a diameter of just below one centimetre by studying the MR tomogram.