The Orbital Index: a novel comprehensive quantitative tool for prediction of delayed enophthalmos in orbital floor fracture management

Prediction of Permanent Enophthalmos Using 3-Dimensional Integral Model in Blowout Fractures

BACKGROUND

The objective of this study is to validate the possibility of setting volumetric surgical indications by predicting permanent enophthalmos using a simplified formula.

METHODS

The volume difference of bilateral orbits in a CT scan was automatically measured, and permanent enophthalmos was predicted by substituting the volume difference into a formula made using the 3-dimensional (3D) integral model.

RESULTS

The predicted enophthalmos showed a strong positive correlation with the permanent enophthalmos of 52 blowout fracture patients. Analyzing CT of 768 pure blowout fracture patients, the mean predicted enophthalmos was 1.84 mm, and both the size of the fracture area and the degree of EOM herniation showed the absence of correlations.

CONCLUSIONS

Through the digitized orbital volume analysis and formula using the 3D integral model, blowout fracture patients who require surgery in the early post-traumatic period can be identified with convenience and reproducibility.