Magnetic resonance imaging of midline brain tumors using inversion recovery sequences at 0.08 T (3.4 MHz).

The use of inversion recovery sequences to highlight intracranial tumors in children is illustrated. The effect of changing the inversion time (TI) to produce the best spatial resolution and to highlight the contrast resolution between different tumors and normal brain is analyzed. The normal appearances and clinical examples in the central nervous system are used to illustrate the options that are available using IR sequences. Variation of TI for providing a means of differentiating short T1 lesions from long T1 lesions is discussed, short TI sequences being best for demonstrating gliomas and astrocytomas whilst medium/long TI sequences are best for demonstrating vascular abnormalities and short T1 tumors. Inversion recovery imaging is considered to be an accurate alternative to spin-echo imaging as currently applied.