Tumour delineation with magnetic resonance imaging in gliomas. A comparison with positron emission tomography and computed tomography.

In ten patients with histopathologically confirmed low-grade (n = 4) and high-grade (n = 6) cerebral gliomas, the ability of magnetic resonance imaging (MRI) to delineate these tumours was examined. Spin echo (SE) technique with dual and multiple echoes and subtraction of images recorded with multiple echo sequences was applied. Computed tomography (CT) and positron emission tomography (PET) with 11C-L-methionine were used as reference methods. In high-grade gliomas multiple echo sequences and subtractions delineated the tumours better than ordinary SE sequences and equally well as CT, but slightly less well than PET. In low-grade tumours, the tumour delineation was better than with CT and comparable to that obtained with the present PET method. Multiple echo sequences and subtraction increase the reliability of MRI in delineating cerebral gliomas as compared with standard SE sequences.