CT diagnosis of orbital blowout fracture

Objective To explore CT findings and diagnosis methods oforbital blowout fracture. Methods Axial thin slices CT scans on orbitsin 45 cases with orbital blowout fracture were performed,as well asadditional coronal thin slices CT scans in some of the cases. ResultsThe results revealed fracture lines in 12 cases,medio-rectus musclehypertrophy in 34 cases, hernia of ocular muscle ant orbital fat intoparnasal sinuses in 35 cases and narrowed or disappeared space betweenmedio-rectus muscle and orbital fat in 34 cases, pneumatosis of orbitand eyelid in 27 cases.Besides,there occurred 36 cases of hydrops orcollapse of paranasal sinus(some of the patients had 2 or more then 2hydroped sinuses.Hydrops occurred in ethmoid sinus in 32 cases,inmaxillary sinus in 3 cases, in sphenoidal sinus in 3 cases and in frontalsinus in 2 cases).Swelling of peri-orbit soft tissue were seen in 45 cases.Conclusion CT is an effective method to diagnose the fracture of orbitalblowout,showing the shape of orbital fracture and the change of softtissue and paranasal sinuses around the rupture of orbital fracture.