Footnotes

• Acknowledgements We thank the patient for his cooperation.

• Contributors All authors made substantial contributions to the conception of the work, data acquisition, drafting the work and revising it for important intellectual content.

• Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.

• Competing interests None declared.

• Patient consent for publication Consent obtained directly from patient(s).

• Ethics approval Not applicable.

• Provenance and peer review Not commissioned. Externally peer reviewed by Stuart Weatherby, Plymouth, UK and Nicola Giffin, Bath, UK.

• Data availability statement There are no additional unpublished data from the study.