AIM: To investigate pathogeny of paralytic strabismus, the patterns of paralytic extraocular muscles and effects of paralytic strabismus on binocular vision.

METHODS: A retrospective study was done in 183 patients with paralytic strabismus who underwent squint correction in our hospital from March 2009 to March 2012.

RESULTS: Of the 183 patients reviewed, the incidence of congenital paralytic strabismus was 80.87%, acquired paralytic strabismus accounted for 19.13%. In 77.60% of the cases, the causes could not be identified, followed by trauma accounted for 14.21%. Among all vertical strabismus the ratio of superior oblique palsy, inferior rectus palsy, superior rectus palsy, double elevator palsy, inferior oblique palsy, double depression palsy accounted for 81.19%, 8.26%, 6.88%, 2.29%, 0.92%, 0.46%, respectively. Among all horizontal strabismus the rate of extra rectus palsy was 54.17%, internal rectus palsy 45.83%. 28.92% of patients who were examined with synoptophore had binocular function.

CONCLUSION: Paralytic strabismus had complex causes. The most common paralytic extraocular muscle was superior oblique muscle. It has important effects on binocular vision. Therefore, surgical treatment should be carried out as early as possible.