Binocular Vision in inferior oblique hyperfunction

Purpose: Investigation of frequency of amblyopia and binocularity in patients with symmetric or asymmetric in­ ferior oblique hyperfunction. Material and methods : This study includes 93 patients with heterotropia which were found to have inferior oblique hyperfunction (IOH) upon examination in İstanbul beyoğlu Hospital Eye Clinic Strabismus Department. 32 patients who had equal İOHF in both eyes were grouped as "symmetric" and 61 pa­ tients who had unequal İOHF as "asymmetric". Findings: İn the group with symmetric İOHF, amlyopia was found in 21.37 % of cases and in asymmetric group 55.73 %. İn 69 patients who had reliable fusion examination, bet- ween the fusion was recorded in 74.07 %in the symmetric group and 35.71 % in the asymmetric group. There was a significant difference two groups (p < 0.05). Results: Because of the risk of developing amblyopia and in- hibition of binocular Vision we, one should follow patients with asymmetric İOHF very carefully.