The Clinical Effect of Preoperative Deviation on Surgical Success and Sensory Function in Infantile Exotropia

Background: This study aims to assess the impact of preoperative deviation on surgical success and sensory function in infantile exotropia. Furthermore, to assess the effects of late surgical timing in these patients.Materials and Methods: This retrospective study evaluated 16 subjects with infantile exotropia that underwent surgical management between 2012 and 2018. Patients with deviation ≤ 50 prism diopters (PD) were added to Group 1, and Patients with deviation > 50 PD were added to Group 2 to assess the impact of preoperative deviation on surgical success and sensory function. The surgical success is descri-bed as ≤5 PD esotropia and ≤10 PD exotropia for patients. The Titmus stereopsis and Worth 4-Dot tests were used for sensory function assessment.Results: The average preoperative deviation was 50,63 ± 18,7 PD (20-90). The median age at the time of surgery was 73 (24-400) months. Surgical success was observed in 75% of the patients after the first surgery, and surgical success was observed in all patients after the second surgery. The sensory function was assessed in 11 testable patients (68.7%), of which 5 (45.4%) fusion was observed in the Worth 4-Point test, and 2 (18.1%) achieved measurable stereopsis. While the preoperative deviation had an effect on fusion, it had no effect on stereopsis and surgical success(p=0,015; p=0,45; p=0,77 respectively).Conclusions: The smaller preoperative deviation may be associated with a higher rate of sensorial fusion development. Furthermore, relatively high surgical success can be achieved with late surgical timing in these patients.Keywords: Exotropia, Preoperative deviation, Strabismus, Stereopsis