Epidural hematoma (EDH) is a traumatic accumulation of blood between the inner table of the skull and the stripped-off dural membrane. EDH results from traumatic head injury, usually with an associated skull fracture and arterial laceration.The inciting event often is a focused blow to the head, such as that produced by a hammer or baseball bat. In 85-95% of patients, this type of trauma results in an overlying fracture of the skull. Blood vessels in close proximity to the fracture are the sources of the hemorrhage in the formation of an epidural hematoma. 

In a study of 41 patients with epidural hematoma at a level I trauma center, the patients’ age, severity of traumatic brain injury, and neurologic status were the main factors influencing outcome. Two patients died within 24hours, and 39 patients (95%) survived. Thirty-two patients (78%) showed good recovery at latest follow-up.[2]

In cases of rare bilateral extradural hematoma (0.5-10%), higher mortality has been reported. Approach to treatment depends on the volume, time of diagnosis, and neurologic deficit level. Simultaneous drainage of bilateral hematomas has been demonstrated to be an effective technique. [34]

 

 

From a clinical standpoint, the patient may have a lucid interval after the head trauma and then develop neurologic deterioration leading to coma (talk and die syndrome). The hematoma acts as a rapidly enlarging mass lesion and may cause brain shifts and herniation.

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An epidural (extradural) hematoma is an accumulation of blood between the calvaria and the underlying dura mater. An epidural hematoma is usually associated with a skull fracture and tearing of the middle meningeal artery.


Pathophysiology

Approximately 70-80% of epidural hematomas (EDHs) are located in the temporoparietal region where skull fractures cross the path of the middle meningeal artery or its dural branches. Frontal and occipital epidural hematomas each constitute about 10%, with the latter occasionally extending above and below the tentorium. Association of hematoma and skull fracture is less common in young children because of calvarial plasticity.

Epidural hematomas are usually arterial in origin but result from venous bleeding in one third of patients. Occasionally, torn venous sinuses cause an epidural hematoma, particularly in the parietal-occipital region or posterior fossa. These injuries tend to be smaller and associated with a more benign course. Usually, venous epidural hematomas only form with a depressed skull fracture, which strips the dura from the bone and, thus, creates a space for blood to accumulate. In certain patients, especially those with delayed presentations, venous epidural hematomas are treated nonsurgically.

Expanding high-volume epidural hematomas can produce a midline shift and subfalcine herniation of the brain. Compressed cerebral tissue can impinge on the third cranial nerve, resulting in ipsilateral pupillary dilation and contralateral hemiparesis or extensor motor response.

Epidural hematomas are usually stable, attaining maximum size within minutes of injury; however, Borovich et al demonstrated progression of epidural hematoma in 9% of patients during the first 24 hours. [5] Rebleeding or continuous oozing presumably causes this progression. An epidural hematoma can occasionally run a more chronic course and is detected only days after injury.

Epidemiology

Epidural hematoma occurs in 1-2% of all head trauma cases and in about 10% of patients who present with traumatic coma.

Reported mortality rates range from 5-43%.

Higher rates are associated with the following:

  • Advanced age

  • Intradural lesions

  • Temporal location

  • Increased hematoma volume

  • Rapid clinical progression

  • Pupillary abnormalities

  • Increased intracranial pressure (ICP)

  • Lower Glasgow coma scale (GCS; see the Glasgow Coma Scale calculator)

Mortality rates are essentially nil for patients not in coma preoperatively and approximately 10% for obtunded patients and 20% for patients in deep coma.

atients younger than 5 years and older than 55 years have increased mortality. Patients younger than 20 years account for 60% of EDHs. EDH is uncommon in elderly patients because the dura is strongly adhered to the inner table of the skull. In case series of EDH, fewer than 10% of patients are older than 50 years.

 

Since the release of the Hib vaccine there has been a dramatic decrease in the incidence as well as a shift in the bacterial etiology. Most cases are now caused by streptococci, staphylococci, nontypeable H influenzae, and Candida albicans. Adults typically have a more indolent course characterized by "severe" sore throat and odynophagia. Direct thermal injury has been reported as a noninfectious cause. On soft tissue lateral neck x-ray, the epiglottis is seen as rounded and blurred (thumbprint sign). Epiglottitis may progress to complete obstruction if not treated. Differential diagnosis includes acute infectious laryngitis, acute laryngotracheobronchitis (croup), acute spasmodic laryngitis, membranous (bacterial) tracheitis, anaphylactic reaction, foreign body aspiration, retropharyngeal abscess, and extrinsic or intrinsic compression of the airway (tumors, trauma, cysts).

 

 

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Mortality rates are essentially nil for patients not in coma preoperatively and approximately 10% for obtunded patients and 20% for patients in deep coma.

If treated early, prognosis usually is excellent, because the underlying brain injury generally is limited.

Outcome from surgical decompression and repair is related directly to patient's preoperative neurologic condition. [1]

Approximately 10% of patients with an epidural hematoma die as a direct result of the hematoma.

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Which of the following statements best explains the condition shown in this image?

Image not available.

The correct answer is D.

The image depicts a small epidural hemorrhage. The fracture line in the temporal bone involves the distribution of the middle meningeal artery.

 

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