Figure 1a-c: 33-year-old male with seizures diagnosed with a WHO °II astrocytoma by stereotactic biopsy. Complete
tumour resection was scheduled. (A) Preoperative definition of target tumour volume of 31.72 cm3 on T2 FLAIR
images. (B) On the first iMRI, a 1.92-cm3 residual tumour is detected at the ventral aspect of the resection cavity
on sharp FLAIR images. (C) Postoperative MRI shows no signs of tumour remnants. iMRI guidance led to a fully
successful procedure with no added neurologic morbidity.