Imaging features of rosette-forming glioneuronal tumours

RGNTs are very rare mixed glioneuronal tumours and mostly affect young people. They are usually hypointense on T1-weighted images and DWI, hyperintense on T2-weighted images, and hypo-attenuated on CT images. The “green bell pepper sign” after gadolinium enhancement, intratumoural haemorrhage, CSF dissemination, and multiple satellite lesions provide additional clues to the correct diagnosis. A relatively well-demarcated tumour with these features and a midline location should raise suspicion of an RGNT.