- Correspondence to Dr Manjit Matharu, Headache and Facial Pain Group, UCL Queen Square Institute of Neurology, London WC1N 3BG, UK;
- Accepted April 27, 2021
- First published June 9, 2021.
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.