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Periorbital Bruising After Fall
This case features a patient presenting with periorbital bruising after a fall, ultimately diagnosed with orbital floor fracture and orbital compartment syndrome.
Imaging overview:
Axial non-contrast CT demonstrates proptosis with a stretched appearance of the optic nerve and posterior globe tenting, defined as a posterior globe angle of less than 130 degrees. Coronal non-contrast CT in soft tissue windows shows intraorbital fat stranding suggestive of retrobulbar hemorrhage. Coronal non-contrast CT in bone windows confirms a fracture of the orbital floor.
Clinical insight:
Orbital compartment syndrome is a clinical emergency in which rising intraorbital pressure compromises perfusion to the optic nerve and retina, threatening permanent vision loss. Key imaging findings include retrobulbar hemorrhage with intraorbital fat stranding, proptosis, optic nerve stretching, and posterior globe tenting. Posterior globe tenting, defined as a posterior globe angle less than 130 degrees, is an important CT marker of elevated intraorbital pressure. When orbital compartment syndrome is suspected clinically, lateral canthotomy and cantholysis should be performed urgently to decompress the orbit and preserve vision, without waiting for imaging confirmation.
Case courtesy of Mira Shoukry, MS4, and Nick Matthees, MD, Mayo Clinic Arizona.