Section Editor: Sandy Cheng-Yu Chen, M.D.
Taipei Medical University Hospital, Taipei, Taiwan
Patients with spontaneous intracranial hypotension typically present with postural headache, nausea, or lower cranial neuropathy due to brainstem sagging. Usually, the cause is some form of spinal CSF leakage which may require an epidural blood patch. Typical SIH may show small subdural hemorrhages involving the bilateral hemispheric convexities on axial CT (A, yellow arrows). Other cause of headache to exclude include subarachnoid hemorrhage, venous sinus thrombosis or pseudotumor cerebri. MRI confirms the diagnosis by showing classic sagging of the brain (B, white arrow) and brainstem (B, yellow arrows). Postcontrast T1-weighted image shows diffuse dural thickening and enhancement (C, white arrows).