AKT-2234

A 68-year-old with a history of type 2 diabetes mellitus and hypertension comes to the clinic complaining of experiencing light flashes in his left eye. He has been experiencing these symptoms for the past 2 days and they seem to occur more at the peripheral part of his vision. There is no pain or redness in the affected eye. His corrected visual acuity is measured as 6/9 in both eyes. What is the most probable diagnosis?