Spontaneous Resolution of Dural Arteriovenous Fistula

A 33-year-old man presented with pulsatile tinnitus and headache for 2 months. He was a smoker, and his medical history was unremarkable. His tinnitus gradually progressed from intermittent to persistent. The sound was captured using his mobile phone positioned over the right temporal region (Audio). His headache evolved from periodic stinging pain to a sustained, distending quality. His headache improved after taking tramadol. Digital subtraction angiography (DSA) demonstrated a dural arteriovenous fistula located in the right temporal region. The right middle meningeal artery served as the feeding artery, with predominant venous drainage into the right external cervical vein and minor drainage into the right cavernous sinus (Fig 1A–C). Brain three-dimensional time of flight magnetic resonance angiography (3D-TOF MRA) demonstrated that the fistulous ostium was situated within the dura anterior to the right temporal pole (Fig 2A). One month later, his symptoms subsided gradually and had completely resolved by 1.5 months. A 2-month follow-up DSA confirmed the disappearance of the fistula (Fig 1D), whereas the 3D-TOF MRA indicated thrombus formation at the fistulous ostium (Fig 2B). Although head injury, dural venous sinus thrombosis (CVST), prior craniotomy, and intracranial infection may cause dural arteriovenous fistulae (dAVFs), the majority of dAVFs belongs to idiopathic fashion. In the present case, there is no special history associated with the lesion, so idiopathic pattern was considered.1 The dAVF's feeding artery was the right middle meningeal artery, and its drainage predominantly into the external cervical vein with minor involvement of the cavernous sinus. The absence of cortical venous drainage established a Borden type I/Cognard type I classification, a grade associated with a low annual risk of neurological events, ranging from 0.0 to 0.6%.1 Although the pulsatile tinnitus and headache were intolerable, the patient has a lower risk of cerebral hemorrhage due to no cortical vein drainage. Spontaneous closure of the dAVFs is not uncommon.2, 3 In this case, by comparing the baseline 3D-TOF MRA with the follow-up images, a focal homogeneous isointense lesion was found at the fistulous ostium. This finding suggests that thrombus formation was the reason for the spontaneous resolution of the present dAVF. X.L. and N.M. contributed to the conception and design of the study; X.L. contributed to the acquisition and analysis of data; X.L. contributed to drafting the text or preparing the figures. Nothing to report.