All are causes of Horner's syndrome except
Pancoast tumor is a tumor in apex of lung which can compress the sympathetic trunk and leads to horner syndrome. Wallenberg syndrome due to aerial hemorrhage or infarct can damage the sympathetic chain running in lateral aspect of medulla and can leads to horner syndrome. Internal carotid aery dissection can damage the sympathetic trunk running posterior to it and can leads to horner syndrome. Neurosyphillis as such doesn't affect the sympathetic fibres directly.
Pancoast tumour
Lateral Medullary (Wallenberg) syndrome
Internal carotid aery dissection
Neurosyphilis
Investigation in ophthalmology and miscellaneous topics