What is the Difference Between Epidural and Subdural?

The main difference between epidural and subdural hematomas lies in their location and the type of blood vessel involved in the bleeding. Both are types of intracranial hematomas that involve bleeding outside of the brain, but they have distinct characteristics:

Epidural Hematoma: This type of hematoma occurs when there is bleeding inside the skull but outside the dura membrane, which is the outermost layer of the brain. Epidural hematomas typically involve an artery, such as the middle meningeal artery, and bleeding can cause pressure to build up in the brain rapidly, often within hours of the injury. They usually result from a skull fracture that tears one of the arteries supplying blood to the brain. Epidural hematomas are more common in adolescents and young adults.
Subdural Hematoma: This type of hematoma occurs when the bleeding exists inside the dura but still outside the brain, in the space between the dura and the arachnoid layers of the membrane. Subdural hematomas involve veins, which tend to bleed and grow more slowly compared to arteries in epidural hematomas. They are more common in older individuals, as the brain shrinks with age and the veins connecting the brain to the dura become more fragile. The elderly and alcoholics with brain atrophy are particularly susceptible since the bridging veins are stretched out and the brain has more space for movement.

In terms of diagnosis, both epidural and subdural hematomas can be identified using CT or MRI scanning. Epidural hematomas appear convex, or lens-shaped, while subdural hematomas are concave or crescent-shaped. Prompt intervention is crucial for both types of hematomas to prevent worsening of the condition and potentially life-threatening complications.