Unlike the Faden technique, the T reduction with Y-split recession is approximately constant throughout the oculomotor range resulting in less incomitance
than that with Faden technique [17-19].
None of the patients had limitation of ocular movement and any lateral incomitance
In the same study, the most common causes of incomitance
were identified as A-V pattern, fourth nerve palsy, asymmetric surgery, Duane retraction syndrome, and Brown syndrome.
In any case, a change in image separation when looking in different directions is a sign of incomitance
, and is much more likely to occur in recent onset neurogenic conditions, or those caused by a mechanical restriction to the movement of the eye.
Y-splitting surgery has also been reported to result in less incomitance
than posterior fixation surgery [4, 7].
(1) Due to the torsional component and the frequency of incomitance
, medical treatment using prisms is generally not tolerated by SOP patients.
The amount of transposition is determined by the degree of incomitance
. It has been shown that horizontal recti transposition collapses the pattern but results in increased objective torsion.