Question

Dr. Roberts was summoned to the emergency department to see a 34-year-old man who was brought in complaining of a headache with nausea and vomiting. He has a 3-inch laceration over the right eyebrow with visible blood and fluid from his nose. He has become confused since arriving in the emergency department. Just prior to the completion of the CT scan, he became difficult to arouse.

1. The preliminary diagnosis is an epidural hematoma. Explain the physiology of an epidural hematoma.

2. Describe the surgical procedure that you anticipate will be completed.

3. What type of incision will be made? Identify the layers from the skin to the brain tissue.

4. Describe the surgical procedure that you anticipate will be completed.

5. What is the difference between a subdural hematoma and an epidural hematoma?

Answer 1

1)Epidural hematoma is a condition caused by acute arterial or venous bleeding in the epidural space. Typical symptoms are headache, confusion, vomiting, loss of consciousness etc. and is due to increased intracranial pressure. Diagnosis can be confirmed by CT and treatment is a neurosurgical opening of the skull and hematoma evacuation.

Epidural space is a space between the outer membrane of the brain called dura mater and the skull.The epidural space has a series of arteries that supply blood to the meninges and is prone to blood collection. The largest meningeal artery called the middle meningeal artery located near the temporal skull is the source of most epidural hematomas.In adults it occurs mostly in temporal regions resulting from tearing of the middle meningeal vessels due to a temporal bone fracture. It may also occur due to venous bleeding that causes laceration of dural venous sinus. In children it mostly occurs from tears of a dural sinus or diploic veins than arterial. Epidural bleeds from arteries can grow spilling blood into the intracranial space and expands the hematoma that can cause increase in intracranial pressure, causing the brain to shift, lose blood supply, be crushed against the skull, or herniate. Epidural bleeds can compresses the brainstem that causes the symptoms.

2)2) A thorough trauma evaluation is done and skull fractures and location of impact is assessed along with stabilizing the airway patency, breathing, and circulation. Surgical procedure involves the removal of the epidural hematoma. Craniotomy is the procedure that involves opening of the skull and removal of epidural hematoma. Another procedure is aspiration that involves cutting a small hole in skull and removes the hematoma using suctions. This method is used if the hematoma is small and is not pressurizing the brain. Neurosurgeons uses magnification glasses and lens in order to visualize delicate nerves and vessels.

3)The procedure is done under general anesthesia. A long arched incision in the scalp is normally made behind the hair line. The skin of scalp is lifted along with peristeum layer.Then soft tissues are folded back to expose skull and drills one or more holes and a flap of skull is removed. Between skull and the brain lies three layers called the meninges. The outermost layer is the dura mater and it is a strong layer, a thin membrane called arachnoid mater and the innermost layer called pia mater.The majority of tissues inside the brain are neural tissues.The dura mater has two layers periosteal layer and meningeal layer. Once the surgeon has access to the hematoma it is removed and then the skull flap is rejoined with screws and plates.

4)Subdural hematoma is caused by bleeding from the veins. It is caused by a brain injury that tears the bridging veins in subdural space. Here bleeding occurs in subdural space between dura and arachnoid. A sudden blow to head as in a car accident or a fall may cause this injury. Epidural hematoma results from bleeding of meningeal artery and bleeding is in epidural space which is between skull and dura.Also the amount of bleeding differs in these two types of hematomas. In epidural hematomas, the blood flow is limited and confined to the tight space between the inner surface of the skull and the outer surface of the dura mater. In subdural hematomas blood may spread to space beneath the dura mater and can reach the front of the head to the rear.