A previously undescribed variant of the confluence of sinuses.

An 8-year-old female with a history of chronic headaches and uncertain papilloedema was found to have a variant of the posterior intracranial dural venous sinuses on magnetic resonance imaging assessment of the brain. Magnetic resonance venography included in the imaging revealed a circular formation of the confluence of sinuses and absent right-sided transverse sinus. The confluence of sinuses is a highly variable structure; however, to the authors' knowledge, a circular confluence of sinuses variant has not been reported in the literature.