Effectiveness of treatment approaches for childhood exotropia: a systematic review

Exotropia (XT), an outward ocular deviation, commonly affects children. Delayed treatment increases the risk of amblyopia and visual impairment. The aim of this systematic review is to evaluate the evidence on the effectiveness, indications, and clinical outcomes of different treatment modalities for childhood XT.

A systematic search was performed in PubMed, Web of Science, ProQuest, Scopus, Google Scholar, EBSCO, and Medline in accordance with PRISMA 2020 guidelines. Articles published between 1997 and 2025 on treatment approaches for childhood XT were included. Treatment success was defined as a post-intervention deviation of ≤10 prism diopters (PD). The review protocol was registered in the International Prospective Register of Systematic Reviews (PROSPERO) under registration number CRD420251174532.

The final review included 34 studies from 11 countries, comprising 3,643 children with a mean age of 5.70 ± 2.24 years. The reviewed studies indicated that part-time occlusion and office-based vergence and anti-suppression therapy (OBVAT) achieved the highest short-term effectiveness rate of 86.8% after follow-up of five months. Overminus lenses therapy achieved a success rate of 80.63% with a follow-up of 2.15 years. Extraocular muscle surgery achieved a success rate of 70.81% with follow-up of 3.68 years, whereas botulinum toxin type A (BTX-A) injection showed a lower effectiveness rate of 66.86% after follow-up of 1.67 years.

Multiple surgical and non-surgical options exist for managing childhood XT. Overminus lenses can improve distance control during testing, but deviation typically return to original state with non-overminus lenses, and their use requires monitoring for possible myopic progression. Surgery remains the primary treatment for constant XT, with bilateral lateral rectus recession and unilateral lateral rectus recession and medial rectus resection (R&R) showing similar short-term outcomes and long-term advantages for R&R. BTX-A offers a minimally invasive alternative for selected cases. Part-time occlusion and OBVAT improve short-term control, however durability and optimal protocols remain uncertain.