Diplopia: When Seeing Double is Worrisome

Diplopia can result from a benign or a life-threatening cause, and therefore it is important to identify and assess diplopia. This review discusses how to approach diplopia in a stepwise manner to identify the underlying etiology and recognize potentially dangerous diplopia, such as a third cranial nerve palsy that could be a harbinger of an aneurysm. The review also highlights the targeted neuroimaging that is required for various clinical scenarios of diplopia.