Abstract
This study examined whether the size and shape of the fluid‐filled space around the spinal cord, called the thecal sac, could help diagnose spontaneous intracranial hypotension (SIH), a condition with low spinal fluid volume, from leaking spinal fluid. Using spinal magnetic resonance imaging scans from 28 patients with SIH and 28 controls, we found that people with SIH had significantly larger thecal sacs than those without the condition. These volume differences could help doctors more accurately identify SIH using noninvasive MRI.