A cystic lesion with an eccentric mural nodule is centred on the internal capsule on the right, with surrounding minor vasogenic oedema. Case Discussion: This patient went on to have a biopsy which confirmed the diagnosis of a pilocytic astrocytoma. And went on to receive radiotherapy. On follow-up gradual regrowth over next 10 years has been shown. Related Articles: Pilocytic astrocytoma.RADIOPAEDIA.ley.