Is There a Connection Between Perivascular Space and Subarachnoid Space?Saylisoy, Suzan MD; Simsek, Sevtap MD; Adapinar, Baki MDJournal of Computer Assisted Tomography: January/February 2014 - Volume 38 - Issue 1 - p 33–35 doi: 10.1097/RCT.0b013e3182a9a45a Neuroimaging Abstract Author Information Perivascular spaces (PVSs) surrounding the walls of arteries, arterioles, and venules do not directly communicate with subarachnoid spaces. There are a few reports exhibiting subarachnoid hemorrhage (SAH) and intracerebral hematomas extending to the PVSs by leakage of the leptomeninges that surround arteries. In this report, we present 4 patients of whom 3 had SAH extending into the PVSs in the bilateral basal ganglia and 1 had extension of contrast medium to the PVSs after injection of the contrast medium into the lumbar subarachnoid space. The hemorrhage extending to the PVSs in our 3 patients with SAH could be explained by leakage of the leptomeninges surrounding the arteries. However, how the contrast medium extends to the PVSs is not clear. We think that, although speculative, incomplete or complete defect at the leptomeninges surrounding the arteries resulting in direct continuity between the subarachnoid space and the PVS allows that blood or contrast media to extend to the PVSs. From the Department of Radiology, Faculty of Medicine, Eskisehir Osmangazi University, Meselik-Eskisehir, Turkey. Received for publication August 15, 2013; accepted August 19, 2013. Reprints: Suzan Saylisoy, MD, Department of Radiology, Faculty of Medicine, Eskisehir Osmangazi University, Meselik-Eskisehir, 26040, Turkey (e-mail: firstname.lastname@example.org). The authors declare no conflict of interest. Copyright © 2014 Wolters Kluwer Health, Inc. All rights reserved.