Magnetic resonance imaging of intracranial neoplasms at 0.02 tesla

Sixty-five patients with single or multiple intracranial neoplasms were examined with an MR imager operating at 0.02 tesla. In 56 patients the diagnosis was histologically confirmed. All patients had an abnormal CT finding. MR images were positive in 59 cases, while the lesion remained undetected or equivocal in 6 cases (2 pituitary adenomas and 4 meningiomas). The MR signal intensity of several meningiomas was equal to that of normal brain tissue. Some astrocytomas were better delineated on MRI than on CT. For the study of pituitary lesions, the spatial resolution was unsatisfactory. The ultralow field MR imager was found to be sensitive for the detection of other intracranial neoplasms.