Footnotes

• Contributors TAH and MWH conceived the idea for the article. TAH, SY and MWH drafted the manuscript. SY supplied fluorescein angiogram images and JSS the neuropathology. AFC reviewed the family history and suggested the diagnosis and GMT and MDF performed the confirmatory DNA analysis. All authors revised the manuscript critically for important intellectual content and gave final approval of the version to be published.

• Funding This work received no specific grant from any funding agency in the public, commercial or not-for-profit sectors.

• Competing interests None declared.

• Patient consent Obtained.

• Ethics approval Liverpool Hospital HREC.

• Provenance and peer review Not commissioned; externally peer reviewed.

• Data sharing statement None.