Clues to dural arteriovenous fistulas in patients with progressive dementia.

The mode of presentation of cranial dural arteriovenous fistulas (DAVFs) is dictated by the pattern of venous drainage. Lesions without demonstrable cortical venous reflux (CVR) have an indolent natural history. Alternatively, the presence of CVR defines aggressive lesions that mandate early diagnosis and definitive intervention (either surgical or endovascular).1 Indeed, it has been previously reported that untreated aggressive DAVF have an annual event rate of 15% and an annual mortality rate of 10.4%.2 While the majority of aggressive DAVFs present with a hemorrhagic complication, an under-recognized presentation is progressive cognitive impairment related to venous congestive encephalopathy.3,4 The largest series to date was reported by Hurst et al who summarized the clinical and radiographic features of five patients with DAVF presenting with dementialike syndromes.5 In this series, however, four of the five patients demonstrated a concomitant decreased level of consciousness or lateralizing findings at presentation. We therefore sought to identify clues on history, physical examination and MRI (magnetic resonance imaging) that would alert the clinician in the absence of decreased level of consciousness or lateralizing findings to a diagnosis of DAVF.