Postmortem diagnosis of fatal venous air embolism due to sigmoid sinus rupture associated with a basilar skull fracture.

BACKGROUND: Venous air embolism (VAE) secondary to basilar skull fractures is rare but potentially fatal. While VAE is a known complication in central venous catheter management, traumatic VAE-particularly in forensic contexts-remains underreported. In forensic medicine, few case reports have detailed the use of postmortem computed tomography (PMCT) to diagnose VAE.

CASE PRESENTATION: A man in his 30 s sustained a head injury at a construction site when his head was caught between a 500-kg steel plate and the ground. Despite resuscitation attempts, spontaneous circulation was not restored, and death was confirmed. PMCT performed 90 h postmortem revealed a basilar skull fracture, facial bone fractures, and approximately 430 mL of gas in the right heart and major systemic veins. Only mild decomposition was noted. Autopsy confirmed a rupture of the right sigmoid sinus and basal dura mater, a skull fracture extending from the right occipital bone to the anterior cranial fossa, and no trauma in the neck or chest. Subarachnoid hemorrhage was observed on the occipital lobes and cerebellar surface, without herniation or cerebral contusion. Brain sectioning showed only small hemorrhages in the brainstem and left basal ganglia. The cause of death was determined to be VAE due to air entry through the right sigmoid sinus.

CONCLUSION: We report a fatal case of VAE caused by air entry through a basilar skull fracture with confirmed rupture of the right sigmoid sinus. This condition may be overlooked without PMCT. Vigilance is essential in severe head trauma cases.