The "CT Comma Sign" in Concurrent Extradural and Hyperacute Subdural Hematomas is Revisited

Abstract

Extradual hematoma (EDH) is the collection of blood between the inner skull table and dura, and appears as a biconvex‑lens shape on imaging.[1,2] In comparison to EDH, the subdural hematoma (SDH) is a collection of blood between the dura and arachnoid membrane and it has a biconcave‑lens shape on imaging.[1,3] In the acute stage, most of these hematomas present as hyperdense lesions on computerized tomography (CT) images.[1‑4] In rare circumstances, a patient can have acute extradural hematoma and subdural hematoma adjacent to each other on the same side with a characteristic imaging appearance.[5,6]

A 26‑year‑old male patient sustained head injury in a road traffic accident and presented 6 hours after to the emergency department. The patient was unconscious from the time of injury and had multiple episodes of vomiting. There was no history of seizures or nasal/ear bleeds. His general and systemic examination was unremarkable. Neurologically, he had altered sensorium [Glasgow coma score (GCS)‑E1V2M5]. Pupils were bilaterally equal and reactive to light. He moved all four limbs normally. He had multiple abrasions over face and scalp.