“…SS may be due to idiopathic cause if there is no detectable bleeding source or secondary when the bleeding lesion can be identified. The cause of bleeding is detected in about half of the cases and the most frequent are in highly vascularized spinal tumors, vascular malformations of the CNS, surgical procedures in the posterior fossa, trauma or previous intradural surgery (Sighary, Cohen-Addad & Linder, 2018;Ribeiro et al, 2013;Hiraka et al, 2018;Fragoso et al, 2017;Fearnley, Stevens & Rudge, 1995;Anderson, Sheffield & Hope, 1999). These bleeds may be infratentorial with deposition of hemosiderin in posterior fossa, brain stem and spine or cortical, in which the deposit is restricted to brain convexities and associated with cerebral amyloid angiopathy (CAA).…”