Pineal region tumours in the sitting position: how I do it

BACKGROUND: Pineal region tumours remain challenging neurosurgical pathologies. METHODS: Detailed anatomical knowledge of the posterior incisural space and its variations is critical. An opaque arachnoidal membrane seals the internal cerebral and basal veins, leading to thalamic, basal ganglia, mesencephalic/pontine infarctions if injured. Medium-size tumours can be removed en-bloc with all traction/manipulation applied on the tumour side, virtually without contact of ependymal surfaces of the pulvinars or third ventricle. Sacrifice of the cerebello-mesencephalic fissure vein may be required. CONCLUSIONS: The sitting position offers superior anatomical orientation and remains safe with experienced teams. Meticulous microsurgical techniques and detailed anatomical knowledge are likely to secure safe outcomes. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s00701-021-04821-3.