The reason for the recognised lack of epidemiological data of all NO conditions presenting to eye departments is attributed to the fact that they often fall in the grey zones between neuro-ophthalmologists, neurosurgeons and neurologists.

. It is anticipated that the findings of the study may then help to support better service planning and resource allocation, as well as identifying any early recognition of rare or emerging patterns.

The current study proposes to collect prospective data on patients seen within an eye department in the UK. The findings of such a prospective study will help to improve understanding of the NO disease burden and temporal trends. It will also help to further identify the demographic and systemic associations of NO conditions. It is anticipated that the findings of the study may then help to support better service planning and resource allocation, as well as identifying any early recognition of rare or emerging patterns. This may help to design clinics with the view to incorporate identifiable multidisciplinary inputs from neurology, neuro-surgery, radiology and emergency services, who are the recognised key stakeholders for the management of NO conditions. Real-world data in such a cohort of NO conditions may also help to detect rare associations or novel disease presentations.

Inclusion Criteria:

• 1. Participants aged ≥ 18 years. 2. Participants seen at the Royal Wolverhampton NHS Trust's Eye Department. 3. Participants with a diagnosis of NO.

Exclusion Criteria:

• 1. Participants aged < 18 years. 2. Participants who do not have a diagnosis of NO. 3. Participants who have opted out of their data being used for research (National Data Opt-out).

Consecutive patients seen at the Royal Wolverhampton NHS Trust's Eye Department who have a NO diagnosis and meet the eligibility criteria will be selected.