Epidural hematoma is when bleeding occurs between the tough outer membrane covering the brain (dura mater) and the

skull The skull is a bone protective cavity for the brain. The skull is composed of four types of bone i.e., cranial bones, facial bones, ear ossicles and hyoid bone. However two parts are more prominent: the cranium and the mandible. In humans, the ...

. Often there is

loss of consciousness Loss may refer to: Arts, entertainment, and media Music * ''Loss'' (Bass Communion album) (2006) * ''Loss'' (Mull Historical Society album) (2001) *"Loss", a song by God Is an Astronaut from their self-titled album (2008) * Losses "(Lil Tjay son ...

following a head injury, a brief regaining of consciousness, and then loss of consciousness again. Other symptoms may include

headache Headache is the symptom of pain in the face, head, or neck. It can occur as a migraine, tension-type headache, or cluster headache. There is an increased risk of depression in those with severe headaches. Headaches can occur as a result ...

, confusion, vomiting, and an inability to move parts of the body. Complications may include

seizures An epileptic seizure, informally known as a seizure, is a period of symptoms due to abnormally excessive or neural oscillation, synchronous neuronal activity in the brain. Outward effects vary from uncontrolled shaking movements involving much o ...

. The cause is typically head injury that results in a break of the

temporal bone The temporal bones are situated at the sides and base of the skull, and lateral to the temporal lobes of the cerebral cortex. The temporal bones are overlaid by the sides of the head known as the temples, and house the structures of the ears. Th ...

and bleeding from the middle meningeal artery. Occasionally it can occur as a result of a bleeding disorder or blood vessel malformation. Diagnosis is typically by a

CT scan A computed tomography scan (CT scan; formerly called computed axial tomography scan or CAT scan) is a medical imaging technique used to obtain detailed internal images of the body. The personnel that perform CT scans are called radiographers ...

or MRI. When this condition occurs in the spine it is known as a spinal epidural hematoma. Treatment is generally by urgent surgery in the form of a craniotomy or

burr hole Trepanning, also known as trepanation, trephination, trephining or making a burr hole (the verb ''trepan'' derives from Old French from Medieval Latin from Greek , literally "borer, auger"), is a surgical intervention in which a hole is drill ...

. Without treatment, death typically results. The condition occurs in one to four percent of

head injuries A head injury is any injury that results in trauma to the skull or brain. The terms ''traumatic brain injury'' and ''head injury'' are often used interchangeably in the medical literature. Because head injuries cover such a broad scope of inju ...

. Typically it occurs in young adults. Males are more often affected than females.

Signs and symptoms

Many people with epidural hematomas experience a lucid period immediately following the injury, with a delay before symptoms become evident. Because of this initial period of lucidity, it has been called "Talk and Die" syndrome. As blood accumulates, it starts to compress intracranial structures, which may impinge on the

third cranial nerve The oculomotor nerve, also known as the third cranial nerve, cranial nerve III, or simply CN III, is a cranial nerve that enters the orbit through the superior orbital fissure and innervates extraocular muscles that enable most movements of ...

, causing a fixed and dilated pupil on the side of the injury.Epidural Hematoma in Emergency Medicine
at Medscape. Author: Daniel D Price. Updated: Nov 3, 2010 The eye will be positioned down and out due to unopposed innervation of the fourth and sixth cranial nerves. Other symptoms include severe

; weakness of the extremities on the opposite side from the lesion due to compression of the crossed pyramid pathways; and vision loss, also on the opposite side, due to compression of the

posterior cerebral artery The posterior cerebral artery (PCA) is one of a pair of cerebral arteries that supply oxygenated blood to the occipital lobe, part of the back of the human brain. The two arteries originate from the distal end of the basilar artery, where it bifur ...

. In rare cases, small hematomas may be

asymptomatic In medicine, any disease is classified asymptomatic if a patient tests as carrier for a disease or infection but experiences no symptoms. Whenever a medical condition fails to show noticeable symptoms after a diagnosis it might be considered asy ...

. If not treated promptly, epidural hematomas can cause

tonsillar herniation Brain herniation is a potentially deadly side effect of very high pressure within the skull that occurs when a part of the brain is squeezed across structures within the skull. The brain can shift across such structures as the falx cerebri, the te ...

, resulting in

respiratory arrest Respiratory arrest is a sickness caused by apnea (cessation of breathing) or respiratory dysfunction severe enough it will not sustain the body (such as agonal breathing). Prolonged apnea refers to a patient who has stopped breathing for a long p ...

. The

trigeminal nerve In neuroanatomy, the trigeminal nerve ( lit. ''triplet'' nerve), also known as the fifth cranial nerve, cranial nerve V, or simply CN V, is a cranial nerve responsible for sensation in the face and motor functions such as biting and chewin ...

may be involved late in the process as the pons is compressed, but this is not an important presentation, because the person may already be dead by the time it occurs. In the case of epidural hematoma in the posterior cranial fossa, tonsillar herniation causes

Cushing's triad Cushing reflex (also referred to as the vasopressor response, the Cushing effect, the Cushing reaction, the Cushing phenomenon, the Cushing response, or Cushing's Law) is a physiological nervous system response to increased intracranial pressure (IC ...

hypertension Hypertension (HTN or HT), also known as high blood pressure (HBP), is a long-term medical condition in which the blood pressure in the arteries is persistently elevated. High blood pressure usually does not cause symptoms. Long-term high bl ...

bradycardia Bradycardia (also sinus bradycardia) is a slow resting heart rate, commonly under 60 beats per minute (BPM) as determined by an electrocardiogram. It is considered to be a normal heart rate during sleep, in young and healthy or elderly adults, a ...

, and irregular breathing.

Causes

The most common cause of intracranial epidural hematoma is head injury, although spontaneous hemorrhages have been known to occur. Epidural hematomas occur in about 10% of traumatic brain injuries, mostly due to car accidents, assaults, or falls. They are often caused by acceleration-deceleration trauma and transverse forces.University of Vermont College of Medicine
"Neuropathology: Trauma to the CNS."
March 2005, Retrieved on February 6, 2007.McCaffrey P. 2001

California State University, Chico. Retrieved on February 6, 2007. Epidural hematoma commonly results from a blow to the side (temporal bone) of the head. The pterion region, which overlies the middle meningeal artery, is relatively weak and prone to injury.Shepherd S. 2004
"Head Trauma."
Emedicine.com. Retrieved on February 6, 2007. Only 20 to 30% of epidural hematomas occur outside the region of the temporal bone. The brain may be injured by prominences on the inside of the skull as it scrapes past them. Epidural hematoma is usually found on the same side of the brain which was impacted by the blow, but on very rare occasions it can be due to a

contrecoup injury In head injury, a coup injury occurs under the site of impact with an object, and a contrecoup injury occurs on the side opposite the area that was hit. Coup and contrecoup injuries are associated with cerebral contusions, a type of traumatic bra ...

. A "heat hematoma" is an epidural hematoma caused by severe

thermal burn A thermal burn is a type of burn resulting from making contact with heated objects, such as boiling water, steam, hot cooking oil, fire, and hot objects. Scalds are the most common type of thermal burn suffered by children, but for adults thermal ...

, causing contraction and exfoliation of the dura mater and exfoliate from the skull, in turn causing exudation of blood from the venous sinuses. The hematoma can be seen on

autopsy An autopsy (post-mortem examination, obduction, necropsy, or autopsia cadaverum) is a surgical procedure that consists of a thorough examination of a corpse by dissection to determine the cause, mode, and manner of death or to evaluate any di ...

as brick red, or as

radiolucent Radiodensity (or radiopacity) is opacity to the radio wave and X-ray portion of the electromagnetic spectrum: that is, the relative inability of those kinds of electromagnetic radiation to pass through a particular material. Radiolucency or hypod ...

, because of heat-induced coagulation of the hematoma.

Pathophysiology

The break of the

causes bleeding from the middle meningeal artery, hence epidural bleeding is often rapid as arteries are high-pressure flow. In 10% of cases, however, it comes from

vein Veins are blood vessels in humans and most other animals that carry blood towards the heart. Most veins carry deoxygenated blood from the tissues back to the heart; exceptions are the pulmonary and umbilical veins, both of which carry oxygenated b ...

s and can progress more slowly. A venous hematoma may be acute (occurring within a day of the injury and appearing as a swirling mass of blood without a clot), subacute (occurring in 2–4 days and appearing solid), or chronic (occurring in 7–20 days and appearing mixed or lucent). In adults, the temporal region accounts for 75% of cases. In children, however, they occur with similar frequency in the

occipital The occipital bone () is a cranial dermal bone and the main bone of the occiput (back and lower part of the skull). It is trapezoidal in shape and curved on itself like a shallow dish. The occipital bone overlies the occipital lobes of the cereb ...

frontal Front may refer to: Arts, entertainment, and media Films * ''The Front'' (1943 film), a 1943 Soviet drama film * ''The Front'', 1976 film Music *The Front (band), an American rock band signed to Columbia Records and active in the 1980s and ea ...

, and posterior fossa regions. Epidural bleeds from arteries can grow until they reach their peak size 6–8 hours post-injury, spilling 25–75 cubic centimeters of blood into the

intracranial space The cranial cavity, also known as intracranial space, is the space within the skull that accommodates the brain. The skull minus the mandible is called the ''cranium''. The cavity is formed by eight cranial bones known as the neurocranium that in ...

. As the hematoma expands, it strips the dura from the inside of the

, causing an intense headache. It also increases

intracranial pressure Intracranial pressure (ICP) is the pressure exerted by fluids such as cerebrospinal fluid (CSF) inside the skull and on the brain tissue. ICP is measured in millimeters of mercury (mmHg) and at rest, is normally 7–15 Millimeter of mercury, mmHg ...

, causing the brain to shift, lose blood supply, be crushed against the skull, or herniate. Larger hematomas cause more damage. Epidural bleeds can quickly compress the

brainstem The brainstem (or brain stem) is the posterior stalk-like part of the brain that connects the cerebrum with the spinal cord. In the human brain the brainstem is composed of the midbrain, the pons, and the medulla oblongata. The midbrain is cont ...

, causing

unconsciousness Unconsciousness is a state in which a living individual exhibits a complete, or near-complete, inability to maintain an consciousness, awareness of self and environment or to respond to any human or environmental Stimulus (physiology), stimulus. ...

, abnormal posturing, and abnormal pupil responses to light.Singh J and Stock A. 2006
"Head Trauma."
Emedicine.com. Retrieved on February 6, 2007.

Diagnosis

Diagnosis is typically by

or MRI. MRIs have greater sensitivity and should be used if there is a high suspicion of epidural hematoma and a negative CT scan. Differential diagnoses include a transient ischemic attack, intracranial mass, or brain abscess. Epidural hematomas usually appear convex in shape because their expansion stops at the skull's sutures, where the dura mater is tightly attached to the skull. Thus, they expand inward toward the brain rather than along the inside of the skull, as occurs in subdural hematomas. Most people also have a skull fracture. Epidural hematomas may occur in combination with subdural hematomas, or either may occur alone. CT scans reveal subdural or epidural hematomas in 20% of unconscious people.Downie A. 2001
"Tutorial: CT in Head Trauma"
. Retrieved on February 6, 2007. In the hallmark of epidural hematoma, people may regain consciousness and appear completely normal during what is called a

lucid interval In emergency medicine, a lucid interval is a temporary improvement in a patient's condition after a traumatic brain injury, after which the condition deteriorates. A lucid interval is especially indicative of an epidural hematoma. An estimated 20 ...

, only to descend suddenly and rapidly into unconsciousness later. This lucid interval, which depends on the extent of the injury, is a key to diagnosing an epidural hematoma. File:Epidural hematoma.png, Nontraumatic epidural hematoma in a young woman. The grey area in the top right is organizing hematoma, causing midline shift and compression of the ventricle. File:Traumatic acute epidual hematoma.jpg, Non-contrast CT scan of a traumatic acute hematoma in the right fronto-temporal area. File:Hematoma.png, A diagram showing an epidural hematoma.

Treatment

Epidural hematoma is a

surgical emergency Surgical emergency is a medical emergency for which immediate surgical intervention is the only way to solve the problem successfully. The following conditions are surgical emergencies: * Acute trauma Cardiothoracic * Cardiac tamponade * Acute ...

. Delayed surgery can result in permanent brain damage or death. Without surgery, death usually follows, due to enlargement of the hematoma, causing a

brain herniation Brain herniation is a potentially deadly side effect of very high pressure within the skull that occurs when a part of the brain is squeezed across structures within the skull. The brain can shift across such structures as the falx cerebri, the te ...

. As with other types of

intracranial hematoma Intracranial hemorrhage (ICH), also known as intracranial bleed, is bleeding within the skull. Subtypes are intracerebral bleeds ( intraventricular bleeds and intraparenchymal bleeds), subarachnoid bleeds, epidural bleeds, and subdural bleeds. ...

s, the blood almost always must be removed surgically to reduce the pressure on the brain. The hematoma is evacuated through a

or craniotomy. If transfer to a facility with neurosurgery is unavailable, prolonged

trephination Trepanning, also known as trepanation, trephination, trephining or making a burr hole (the verb ''trepan'' derives from Old French from Medieval Latin from Greek , literally "borer, auger"), is a surgical intervention in which a hole is drille ...

(drilling a hole into the skull) may be performed in the emergency department. Large hematomas and blood clots may require an open craniotomy. Medications may be given after surgery. They may include antiseizure medications and hyperosmotic agents to reduce brain swelling and intracranial pressure. It is extremely rare to not require surgery. If the volume of the epidural hematoma is less than 30 mL, the clot diameter less than 15 mm, a

Glasgow Coma Score The Glasgow Coma Scale (GCS) is a clinical scale used to reliably measure a person's level of consciousness after a brain injury. The GCS assesses a person based on their ability to perform eye movements, speak, and move their body. These thre ...

above 8, and no visible neurological symptoms, then it may be possible to treat it conservatively. A CT scan should be performed, and watchful waiting should be done, as the hematoma may suddenly expand.

Prognosis

The prognosis is better if there was a lucid interval than if the person was comatose from the time of injury. Arterial epidural hematomas usually progress rapidly. However, venous epidural hematomas, caused by a dural sinus tear, are slower. Outcomes are worse if there is more than 50 mL of blood in the hematoma before surgery. Age, pupil abnormalities, and Glasgow Coma Scale score on arrival to the emergency department also influence the prognosis. In contrast to most forms of traumatic brain injury, people with epidural hematoma and a Glasgow Coma Score of 15 (the highest score, indicating the best prognosis) usually have a good outcome if they receive surgery quickly.

Epidemiology

About 2 percent of head injuries and 15 percent of fatal head injuries involve an epidural hematoma. The condition is more common in teenagers and young adults than in older people, because the dura mater sticks more to the skull as a person ages, reducing the probability of a hematoma forming. Males are affected more than females.

References

External links

MedPix: Epidural hematoma

Epidural hematoma , Radiology Case , Radiopaedia.org
{{DEFAULTSORT:Epidural Hematoma Cerebrovascular diseases Neurotrauma Wikipedia medicine articles ready to translate de:Hirnblutung#Epiduralblutung