Increasing the Accuracy of Orbital Reconstruction With Selective Laser-Melted Patient-Specific Implants Combined With Intraoperative Navigation

Abstract

Advances in technology have allowed increasing degrees of accuracy in the treatment of orbital deformities. The purpose of this study was to compare the accuracy of pre-bent titanium mesh (PBTM) and selective laser-melted patient-specific implants (PSIs) in unilateral orbital reconstruction after traumatic injury. The authors hypothesized that selective laser-melted PSIs would more accurately reconstruct the orbit. A retrospective review of 34 cases of primary reconstruction of unilateral orbital fractures treated using selective laser-melted PSIs (group 1, n= 17) or PBTM (group 2, n= 17) was performed. The primary outcome measurements were orbital volume excess and the anterior, medial, and posterior intraorbital angles. The Mann-Whitney U test was used to assess the difference in orbital volume and angular deviation between the 2 groups. The level of statistical significance was set at .05. All Pvalues were 2-sided. The comparison of mean values for the 2 groups showed significant differences for the anterior angle (PBTM: mean, 11.3; standard deviation [SD], 1.8; PSI: mean, 4.1; SD, 0.7; P= .001), but not the medial (PBTM: mean, 11.6; SD, 2.0; PSI: mean, 8.2; SD, 1.9; P= .170) and posterior (PBTM: mean, 10.8, SD, 2.8; PSI: mean, 8.2, SD, 1.4; P= .760) angles between the unaffected and reconstructed orbits. The postoperative difference in volume between the unaffected and reconstructed orbits differed significantly between the 2 study groups (PBTM: mean, 0.6; SD, 0.1; PSI: mean, 0.4; SD,0.1; P= .029). The results of this study suggest that complex orbital fractures can be reconstructed with an even higher degree of accuracy with selective laser-melted PSIs than with PBTM.