Revisiting bilateral bony orbital volumes comparison using 3D reconstruction in Korean adults: a reference study for orbital wall reconstruction, 3D printing, and navigation by mirroring

Orbital wall fractures can result in changes to the bony orbital volume and soft tissue. Restoring the bony orbital and intraconal fat volumes is crucial to prevent posttraumatic enophthalmos and hypoglobus. We aimed to establish an evidence-based medical reference point for "mirroring" in orbital wall reconstruction, which incorporates three-dimensional (3D)-printing and navigation-assisted surgery, by comparing bilateral bony orbital volumes.We retrospectively analyzed the data obtained from 100 Korean adults who did not have orbital wall fractures, categorized by age groups. The AVIEW Research software (Coreline Soft Inc., Seoul, South Korea) was used to generate 3D reformations of the bony orbital cavity, and bony orbital volumes were automatically calculated after selecting the region of interest on consecutive computed tomography slices.The mean left and right orbital volume of males in their 20 s was 24.67 ± 2.58 mL and 24.70 ± 2.59 mL, respectively, with no significant difference in size (p = 0.98) and Pearson's correlation coefficient of 0.977 (p < 0.001). No significant differences were found in orbital volumes in other age groups without fractures or in patients with nasal bone fractures (p = 0.84, Pearson's correlation coefficient 0.970, p < 0.001). The interclass correlation coefficients (2,1) for inter- and intrarater reliability were 0.97 (p < 0.001) and 0.99 (p < 0.001), respectively.No significant differences were found in the bilateral bony orbital volumes among males of any age. Thus, the uninjured orbit can be used as a volumetric reference point for the contralateral injured orbit during orbital wall reconstruction.