Objective: The orbital blowout fracture is a common facial injury, carrying with it a risk of visual impairment and undesirable cosmetic results unless treated properly. Optimal timing of the surgical treatment is still a matter of debate. We set out to determine whether a meta-analysis would bring us closer to an answer to this question. 

Data Sources: PubMed, EMBASE, Web of Science, and the Cochrane Library were searched from January 1980 to August 2014. We applied the following inclusion criteria: isolated blowout fractures, presenting early and late surgery groups (<14 and >14 days). Patients were evaluated for diplopia and enophthalmos. 

Review Methods: We followed the statements of PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analyses). Pooled odds ratios were estimated with the fixed effects method of Mantel-Haenszel. 

Results: We identified 5 studies with available outcome data (N = 442). Patients in the late group showed an odds ratio of 3.3 (P =.027) for persistent postoperative diplopia as compared with the early group. We found no significant difference between the groups when assessing postoperative enophthalmos as an isolated symptom. 

Conclusion: We found a significantly increased risk of persistent diplopia in patients who were operated >14 days after the trauma.