Two cases of dural arteriovenous fistula presenting with parkinsonism and progressive cognitive dysfunction.

Dural arteriovenous fistula (DAVF) is a rare type of cerebral arteriovenous malformation. The occurrence of parkinsonism together with progressive cognitive dysfunction caused by DAVF has been rarely reported. The probable underlying pathophysiology could be due to venous hypertension caused by DAVF which leads to basal ganglia and cortical dysfunction. Here, two DAVF cases were reported presenting with parkinsonism and progressive cognitive dysfunction. A 54-year-old man (case 1) and a 75-year-old man (case 2) presented with bradykinesia, gait disturbances and cognitive dysfunction who were initially misdiagnosed as having Parkinson's disease. Case 1 exhibited a characteristic type of subcortical calcification on CT scan, while case 2 had specific resting tremor and intracranial hypertension. Both cases showed transient response to the dopaminergic treatment. After 3D time-of-flight (TOF) magnetic resonance arteriography (MRA) or digital subtraction arteriography (DSA), they were diagnosed as having DAVF. This report suggests the possibility of DAVF in patients presenting with parkinsonism and progressive cognitive dysfunction, which requires further attention to be paid, especially in those with transient response to levodopa. Early 3D TOF MRA or DSA is recommended for the diagnosis of DAVF.