United States skier has revealed that he should have undergone eye surgery before taking part in the downhill skiing event on Sunday.
Miller said that while his vision is perfect in good daylight, he could not compete as well as he would have wished when the light fell, which resulted in a disappointing eight-place for the American at the Sochi Games.
"I was supposed to [have] eye surgery earlier this year," Miller told The AP.
"We just never found the time to do it because the race schedule was so tight. We were pretty [upset] looking back on that that we hadn't figured out a time to do that, because for me my vision is critical.
"When the light is perfect I can ski with any of the best guys in the world. When it goes out, my particular style suffers more than the guys who are more stable and sort of don't do as much in the middle of the turns."
Miller has won five Olympic medals for the USA.