“…The most common tumor types in the IV ventricle and brainstem are medulloblastomas ( 2 , 10 , 15 , 21 – 26 ) (7–93.3%), metastases ( 2 , 3 , 21 , 25 , 27 , 28 ) (4.8–46.4%), ependymomas ( 2 , 3 , 9 , 15 , 21 – 30 ) (6.7–38%), astrocytomas (grade I–IV) ( 2 , 3 , 9 , 21 – 26 , 28 , 30 ) (7.3–33%), subependymomas ( 2 , 22 ) (9–19.5%), chorioidpapillomas ( 2 , 9 , 21 – 23 , 26 , 30 ) (2.2–14.6%), and hemangioblastomas ( 2 , 3 , 9 , 15 , 21 – 23 , 25 ) (4.9–14.3%).…”