Some conditions fall between specialties: optic neuritis is a very good example. It presents with visual disturbance, sometimes with eye pain, and a patient is likely to be referred to an ophthalmologist—from optician, emergency department or primary care. Many of the important differential diagnoses are ophthalmological, though not all, and the ophthalmologist is usually concerned about the neurological implications of the diagnosis—a concern that the patient often shares after only a brief internet search. Thus, patients with optic neuritis often attend a neurologist, particularly if there are atypical features. In this edition of Practical Neurology, Dinushi Weerasinghe and Christian Lueck (see page 96) explore the mimics and chameleons of optic neuritis, a paper that should help us in making the diagnosis more secure and to increase awareness of the ophthalmological differentials.

Another clinical area of overlap occurs when children with neurological disorders grow …