Later life cognitive impairment: an ophthalmological diagnostic clue?

Although cognitive impairment in later life is often due to neurodegenerative and cerebrovascular disease, precise diagnosis may sometimes be difficult, particularly in the context of multi‐morbidities. In addition, although the genetic aetiology of neurological diseases is increasingly defined, the full spectrum of clinical features associated with particular genetic mutations may be uncertain. Here the authors present a case that illustrates some of these problems, and in which neurological signs may have been a clue to the underlying cognitive diagnosis.