Chronic pain: Pain (an unpleasant sense of discomfort) that persists or progresses over a long period of time. In contrast to acute pain that arises suddenly in response to a specific injury and is usually treatable, chronic pain persists over time and is often resistant to medical treatments.
Common causes of the condition include: 1  Muscle imbalance (strabismus). The most common cause of lazy eye is an imbalance in the muscles that position the eyes. 2  Difference in sharpness of vision between the eyes (refractive anisometropia).
What Causes Eye Flickering: Eye flickering or eye twitching is quite common among people. 1  Usually, the bottom eye lid is the one that is involved in twitching, but quite often the top eye lid may also begin to twitch. 2  This flickering or twitching can be very annoying.