Not very long ago neurologists made almost exclusively clinical diagnoses untroubled by scans or genetic tests. Diagnoses were proved right or wrong with time and sometimes pathology. This type of neurology was very difficult. Training was long and neurology was the province of the neurologist.

Technological advances introduced scanners, genetic tests, improved neurophysiology and more sophisticated neurological diagnoses. These investigations were still scarce and often were only available in neuroscience centres. A significant part of neurological expertise was the optimum use of these scarce resources for patient management.

More recently there has been a huge expansion in the provision of these technological aids to diagnosis. Scanners are much more widely available – and much more sophisticated. MR sequences such as diffusion weighting can be used to distinguish between old and new changes to tell you about the time course of events and not simply anatomical changes. The internet has also made access to information on rare and unusual diseases much easier – with journals such as this available online. This democratisation of the provision of …