Transverse and Sigmoid Sinus Dural Arteriovenous Fistula Mimicking Idiopathic Intracranial Hypertension and Carotid Cavernous Fistula.

Intracranial dural arteriovenous fistulas (dAVFs) can produce a variety of symptoms depending on fistula location, size, and venous drainage. Although cavernous sinus fistulas (CCFs) classically present with symptoms of orbital venous congestion due to retrograde venous drainage into the superior ophthalmic vein (i.e. an arterialised "red eye") (Miller NR. Neurosurg Focus 2007;23:1--15), dAVFs not localised to the cavernous sinus rarely present with a "red eye" and instead produce increased intracranial pressure, which can mimic idiopathic intracranial hypertension (IIH). The authors present a unique case of an intracranial dAVF with clinical features suggestive of both CCF and IIH. Clinicians should be aware of this possibility to avoid delayed diagnosis of the intracranial dAVF.