MATERIALS AND METHODS: A retrospective review of patients who underwent horizontal strabismus surgery between 2013 and 2017 in Hospital Universiti Sains Malaysia was conducted. Surgery was considered successful if the post-operative deviation was within 10 prism diopters at 6 months' postoperative period. Factors influencing the outcome of surgery at 6 months were identified. Chi-square and Fisher's exact tests were used in data analysis.

RESULTS: Ninety-eight patients were included. Both genders were equally affected. Exotropia (58.2%) was the most common type. About 65.3% of patients had alternating strabismus, while 51% had an angle of deviation of more than 45 prism diopters. Amblyopia was documented in 14.3% of patients. Those operated on below 10 years of age comprised 64.3%. Ninety-four patients completed follow-ups at 6 months after the surgery. The success rate was 81.6%. Approximately 92% of the patients had best-corrected visual acuities of 6/12 and better at 6 months' postoperative period. There was no significant association between age of onset, gender, presence of amblyopia, type of deviation, amount of deviation, and postoperative best-corrected visual acuity with surgical outcome at 6 months' postoperative period (P > 0.05).