A Case of Contralateral Pseudo Inferior Oblique Overaction after Unilateral Inferior Oblique Anterior Transposition

ABSTRACT

There are a large number of reports documenting the effectiveness of the inferior oblique anterior transposition (IOAT)procedure for ipsilateral inferior oblique overaction (IOOA)occurring secondarily to the suprior oblique muscle palsy.However after this procedure, the limitation of elevation in abduction of operated eye may cause apparent IOOA of the contralateral eye, and differentiation of the causes should be required for proper treatment.The primary inferior oblique overaction, inferior oblique overaction in masked bilateral superior oblique palsy and pseudo inferior oblique overaction of the contralateral eye may be the possible causes.We performed IOAT procedure on a 35 year old man showing left hypertropia with IOOA becasuse of left superior oblique palsy.Five months after the operation, we observed the contralateral inferior oblique overaction and diagnosed as the pseudo inferior oblique overaction followed by the limitation of elevation of the operated eye.This patient was successfully treated by recessing the transpositioned inferior oblique muscle posteriorly.We report this case with literature review.