Geraint graduated from the University of Cardiff in 2002 after intercalating and gaining a BSc in Medical Genetics in 2001. He commenced his ophthalmic training in South Wales and completed his basic specialist training in the Oxford deanery in 2005. He took up a position as a Specialist Registrar in the West Midlands in 2006.
He was awarded a prestigious Wellcome Trust clinical research fellowship in 2008, completing his PhD in 2012 and achieving international prizes for his work researching scarring diseases of the ocular surface. He was an NIHR Clinical Lecturer in Ophthalmology at the University of Birmingham from 2012 to 2014. He combined this role with advanced subspecialty training in cornea and external disease at the Birmingham and Midland Eye Centre and continued his senior anterior segment training at the Queen Elizabeth Hospital Birmingham and Moorfields Eye Hospital, London.
He completed advanced clinical fellowship in cataract, corneal and refractive surgery at the Singapore National Eye Centre from 2014 to 2015, working with international leaders in their field. He received his diploma in cataract and refractive surgery (PGDip Cat Ref) from the University of Ulster in 2020, graduating with distinction.
Geraint led the corneal service in Worcestershire from 2016 to 2021. He was appointed as consultant ophthalmologist at the Wye Valley NHS Trust in Herefordshire in 2021, serving patients in the county and Mid Wales.
He is a visiting professor at Ulster University and module lead for re-operative assessment in cataract and refractive surgery for the Postgraduate Diploma in Cataract and Refractive Surgery. He holds the Certificate in Laser Refractive Surgery from the Royal College of Ophthalmologists.