Brainstem death due to intracranial hypertension with hydrocephalus, produced by a third ventricular colloid cyst

We describe the clinical presentation and CT findings of a 10-year-old female patient about half an hour prior to cardiorespiratory arrest and subsequent death, resulting from brainstem compression and herniation caused by hydrocephalus and intracranial hypertension, produced by a previously undetected colloid cyst occluding foramina of Monro on both sides. While third ventricular colloid cysts are rare lesions, sudden unpredicted deaths have been attributed to undetected colloid cysts in many case reports, with some authors even considering that 10% of colloid cyst patients suffer such ends. However, there is still no conclusive or comprehensive guideline regarding how to prevent such situations. We make a short literature review and put forward a few recommendations or learning points to that end.