Non-traumatic subperiosteal orbital hemorrhage secondary to barotrauma.
To report a case of non-traumatic subperiosteal hemorrhage (NTSOH) secondary to barotrauma. Observational case report. A 42-year-old female presented with right proptosis with bilateral petechial lid hemorrhages, chemosis and diplopia following scuba diving. This occurred in the context of a tight facemask resulting in 'mask squeeze', and performance of Valsalva maneuver to equalize ear pressure. Clinically, there were no signs of optic nerve involvement. Computed tomography (CT) demonstrated signs consistent with right subperiosteal hematoma adjacent to the orbital roof with inferolateral displacement of the superior rectus. Patient recovered well after being admitted for intravenous dexamethasone without surgical intervention. NTSOH from barotrauma can result from 'mask squeeze' under a tight-fitting mask and exacerbated by use of Valsalva maneuvers. This may be prevented with frequent pressure equalization during diving.