Lee qualified at University College Hospital, London, and Middlesex Hospital, initially practising as a general practitioner in West Norfolk for four years before choosing to specialise in ophthalmology in 1995. He joined ACES Eye Clinic in 2010 specialising in medical ophthalmology and was also the clinical lead for teaching, serious incident reporting and audit until 2021. He remains the clinical lead for teaching and education for optometrists and ophthalmic care assistants at ACES. In addition, Dr O’Mara also worked for the Queen Elizabeth Hospital, King’s Lynn as a trust specialist in ophthalmology, a post he held for 26 years.