Linear Computed Tomographic Measurement of Soft Tissue Herniation into the Maxillary Sinus as an Indicator for Orbital Floor Fracture Surgery: A Preliminary Study.

Introduction: Computed tomography (CT) is the gold standard radiological assessment for orbital floor fractures and several evaluation methods have been developed. However, no definitive consensus has yet been achieved. We propose a new, linear radiological parameter that may help surgeons to decide when to treat an orbital floor fracture. Materials and Methods: This study retrospectively analysed 328 patients with orbital floor fractures. Both operative or conservative treated patients were included. All CT scans were examined and the linear extents of soft tissue herniation into the maxillary sinus were calculated. Results: The 328 patients were subdivided into three groups: Group A who did not undergo surgery (77.74%); group B (12.2%) who underwent surgery to treat maxillofacial fractures, not orbital floor fractures (12.2%); and group C (10.06%) who underwent surgical repair of the orbital floor. The mean soft tissue herniations were 2.72, 3.21 and 7.48 mm in groups A, B, and C. An ROC (Receiver Operating Characteristics) curve was drawn to identify the optimal cutoff dividing patients who did or did not undergo surgical repair of orbital floor fractures; this was 4.3 mm (sensitivity = 90.91%; specificity = 73.56%).Our proposed radiological parameter seems to accurately correlate with the surgical indications for orbital floor fracture treatment.