ObjectiveTo investigate influencing factors of persistent diplopia after orbital floor blowout fracture reconstruction surgery.

MethodsA case control study was conducted.Data of 146 eyes of 146 orbital floor blowout fracture patients with diplopia occurring 1 day after operation were collected in Henan Eye Hospital from July 2011 to July 2020.The patients were divided into two groups, persistent diplopia group (14 cases 14 eyes) and disappeared diplopia group (132 cases 132 eyes), according to the persistence of diplopia in the follow-up.Differences in sex, right or left eye, age, preoperative course of disease, preoperative intraorbital soft tissue hernia, operation methods, operation approach, postoperative eyeball rotation exercise compliance, the number of eyes with postoperative inferior rectus muscle damage level were compared between the two groups to select factors with P<0.05 for multifactor logistic regression analysis.This study protocol adhered to the Declaration of Helsinki and was approved by the Ethics Committee of Henan Eye Hospital (No.HNEECKY-2021[15]).

ResultsAll eyes were successfully operated and no complications such as infection or dislocation of the orbital implant occurred in any of the eyes during the postoperative follow-up period.There were statistically significant differences in age, preoperative course of disease, preoperative intraorbital soft tissue hernia, operation methods, postoperative eyeball rotation exercise compliance and postoperative inferior rectus muscle injury between the two groups ( χ ² =9.443, P=0.002; χ ² =29.041, P<0.001; H=53.943, P<0.001; H=34.583, P<0.001; χ ² =46.041, P<0.001; H=101.438, P<0.001). The multiple logistic regression analysis indicated that the long preoperative course of disease ( OR=8.678, 95% CI=1.013-74.304, P=0.031), preoperative intraorbital soft tissue hernia (Severe: OR=32.963, 95% CI=7.647-142.084, P<0.001.Moderate: OR=11.852, 95% CI=2.679-52.436, P=0.001), and postoperative inferior rectus muscle injury (Severe: OR=511.000, 95% CI=42.815-6 110.808, P<0.001.Moderate: OR=132.000, 95% CI=12.442-1 400.458, P<0.001) were independent risk factors for postoperative persistent diplopia.Advanced operation methods (Individualized shaped titanium mesh method: OR=0.020, 95% CI=0.002-0.127, P<0.001.Manufacturers prefabricated titanium mesh method: OR=0.031, 95% CI=0.004-0.257, P=0.001), and the postoperative eyeball rotation exercise ( OR=0.015, 95% CI=0.001-0.197, P<0.001) were independent protective factors for postoperative persistent diplopia.

ConclusionsSevere preoperative intraorbital soft tissue hernia and postoperative inferior rectus muscle injury are the main risk factors for persistent postoperative diplopia after orbital floor blowout fracture repair surgery.Shortening the preoperative course of disease, improving the operation methods, and enhancing postoperative ocular functional exercises may reduce the incidence of postoperative persistent diplopia.