A 70 year old man presents to the ED complaining of pain and swelling around his right eye. On taking a thorough history you note that he has had dry eyes for several years, but no other history of eye problems. He has essential hypertension, well controlled on bendroflumethiazide and is otherwise well, taking no other regular medications, and with no allergies.
Baseline observations:
HR 73
BP 142/80
RR 14
SpO2 98% on air
T 37
Capillary blood glucose 5.1