Teaching NeuroImages: Reversible cognitive impairment with bithalamic lesions caused by a dural arteriovenous fistula

A 54-year-old man developed apathy and memory impairment in 3 months. MRI showed bilateral thalamic hyperintensities with dilated cortical veins in the right cerebellum. Angiography revealed dural arteriovenous fistula (dAVF) at right transverse-sigmoid sinuses with retrograde flow through the vein of Galen (figure 1). Transvenous coil embolization improved his MRI findings (figure 2) and Wechsler Memory Scale–Revised scores from 55 at baseline to 105 in the delayed recall index.