Spontaneous Intracranial Hypotension With Prominent Dorsal Perimedullary Veins Mimicking a Spinal Dural Arteriovenous Fistula

SUMMARY: Enlarged and tortuous veins along the dorsal aspect of the spinal cord are traditionally associated with a spinal dural arteriovenous fistula (dAVF). We present six cases demonstrating prominent dorsal perimedullary spinal veins in patients without a dAVF, but rather with a spinal CSF leak resulting in spontaneous intracranial hypotension (SIH). This imaging appearance can closely mimic the classic venous congestion with prominent dorsal perimedullary veins seen with dAVF, creating a potential diagnostic pitfall. The diagnostic workup of a spinal dAVF differs substantially from that of SIH, thus making accurate distinction between these two entities critical. Compared to patients with dAVF, patients with SIH more commonly present with orthostatic headache, absence of lower extremity weakness or paresthesia, brain sagging, and lack of spinal cord edema. Recognition of this pattern may help avoid unnecessary spinal angiography and prompt appropriate evaluation for an underlying spinal CSF leak.