Moran Eye has a really good ppt presentation on this

There are 9 positions of the eye Of which, 6 are cardinal, because 6 represent 1 primary muscle The 6 are: - elevation and depression in adducted (obliques) - elevated and depression in abducted (superior/inferior rectus) - abduction/adduction

The are 3 gazes include elevation in mid position, neutral gaze, and depression

We grade the movements from -4 to+4 0 is perfect -1 = -25% deficit -2 = -50% defict -3 = -75% deficit -4 = 100% deficit, no movement at all ‘+’ values represent equivalent overcorrection