On your first time leading the ICU night shift in a District General Hospital, an urgent bleep call rushes you to ED Resus. A concerned Emergency Physician briefs you about his patient, a 49 y/o female awaiting elective surgical review for a multinodular goitre with retrosternal extension.

A 67-year-old lady with a background of hypertension presents to ED complaining of unilateral vision loss. This started 3 days ago when she saw some flashing lights. Since then, there has been progressive visual loss and darkness spreading from the temporal aspect of her visual field towards the centre. She has no eye pain, headache or jaw ache.