I've had them for over 35 years.
Low dose aspirin keeps them away. Through trial and error, I've determined that taking the low dose aspirin (81mg) 3 times per week is enough to prevent them from happening. Mine were usually associated with bright lights or intensely examining details in a bright lighting or sometimes computer use. A opthomologist recommended the aspirin but 5mg per day caused too much bruising as did the low dose, if I took it every day.