Epidural hematoma
Encyclopedia
Epidural or extradural hematoma (haematoma) is a type of traumatic brain injury
(TBI) in which a buildup of blood occurs between the dura mater
(the tough outer membrane of the central nervous system
) and the skull
. The dura mater also covers the spine, so epidural bleeds may also occur in the spinal column. Often due to trauma
, the condition is potentially deadly because the buildup of blood may increase pressure
in the intracranial space and compress delicate brain tissue. The condition is present in one to three percent of head injuries
. Between 15 and 20% of patients with epidural hematomas die of the injury.
and subarachnoid hemorrhage
s, are extra-axial bleeds, occurring outside of the brain tissue, while intra-axial hemorrhages, including intraparenchymal
and intraventricular hemorrhage
s, occur within it.
After the epidural hematoma begins collecting, it starts to compress intracranial structures which may impinge on the CN III. This can be seen in the physical exam as a fixed and dilated pupil on the side of the injury.The eye will be positioned down and out due to unopposed CN VI innervation.
Other manifestations will include weakness of the extremities on the same side as the lesion due to compression of the crus on the opposite side of the lesion, and a loss of visual field opposite to the side of the lesion due to compression of the posterior cerebral artery on the side of the lesion.
The most feared event that takes place is the transtentorial, or uncal herniation which results in respiratory arrest as the medullary structures are compromised. The trigeminal nerve (CN V) may be involved late in the process as the pons becomes compressed, but this is not a significant clinical presentation since by that time the patient may already be dead.
Epidural bleeding is rapid because it is usually from arteries, which are high pressure. Epidural bleeds from arteries can grow until they reach their peak size at six to eight hours post injury, spilling from 25 to 75 cubic centimeters of blood into the intracranial space. As the hematoma expands, it strips the dura from the inside of the skull, causing an intense headache. Epidural bleeds can become large and raise intracranial pressure
, causing the brain to shift, lose blood supply, or be crushed against the skull. Larger hematomas cause more damage. Epidural bleeds can quickly expand and compress the brain stem, causing unconsciousness
, abnormal posturing
, and abnormal pupil
responses to light.
On images produced by CT scans and MRIs, epidural hematomas usually appear convex in shape because their expansion stops at 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 hematoma
. The lens like shape of the hematoma leads the appearance of these bleeds to be called "lentiform".
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 patients. In the hallmark of epidural hematoma, patients may regain consciousness during what is called a lucid interval
, only to descend suddenly and rapidly into unconsciousness later. The lucid interval, which depends on the extent of the injury, is a key to diagnosing epidural hemorrhage. If the patient is not treated with prompt surgical intervention, death is likely to follow.
, although spontaneous hemorrhage is known to occur. Hemorrhages commonly result from acceleration-deceleration trauma and transverse forces. 10% of epidural bleeds may be venous
, due to shearing injury from rotational
forces. Epidural hematoma commonly results from a blow to the side of the head. The pterion
region which overlies the middle meningeal artery is relatively weak and prone to injury. Thus 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 that was impacted by the blow, but on very rare occasions it can be due to a contrecoup injury.
. If transfer to a facility with neurosurgery is prolonged trephination may be performed in the emergency department.
), or as a rare complication of anaesthesia (such as epidural
anaesthesia) or surgery (such as laminectomy
).
The anatomy of the epidural space means that spinal epidural hematoma has a different profile from cranial epidural hematoma. In the spine, the epidural space contains loose fatty tissue, and the epidural venous plexus, a network of large, thin-walled veins. This means that bleeding is likely to be venous. Anatomical abnormalities and bleeding disorders
make these lesions more likely. They may cause pressure on the spinal cord or cauda equina
, which may present as pain, muscle weakness, or bladder and bowel dysfunction. The diagnosis may be made on clinical appearance and time course of symptoms. It usually requires MRI scanning to confirm. The treatment is surgical decompression. The incidence of epidural hematoma following epidural anaesthesia is extremely difficult to quantify; estimates vary from 1 per 10,000 to 1 per 100,000 epidural anaesthetics.
caused by this blow." [from the translation by E. J. Trechmann]
On February 20, 1998, 38 year-old Indian cricketer Raman Lamba
was hit on the head by a cricket ball while fielding without a helmet. Although Lamba walked off the field and the injury did not appear to be serious at the time, he succumbed to internal hemorrhage three days later.
On April 17, 2003, at age 72, Dr. Robert Atkins
, creator of the Atkins diet, slipped on the ice while walking to work, hitting his head and causing bleeding around his brain. He lost consciousness on the way to the hospital, where he spent two weeks in intensive care. His death certificate states that the cause of death was "blunt impact injury of head with epidural hematoma".
On March 18, 2009, actress Natasha Richardson
died as a result of an epidural hematoma sustained two days earlier while skiing in Mont-Tremblant
, Québec, Canada. Like many patients, she had a lucid interval where she did not exhibit any symptoms until approximately an hour after her fall when she complained of a headache. By the time she reached medical care, the hematoma had already caused significant damage.
On May 26, 2010, actor Gary Coleman
was admitted to Utah Valley Regional Medical Center in Provo, Utah, after falling and hitting his head and suffering an epidural hematoma at his home in Santaquin, Utah. He was announced to be in critical condition. By mid-afternoon on May 27, 2010, Coleman was unconscious and on life support. He died at 12:05 p.m. MDT (18:05 UTC) on May 28, 2010.
Traumatic brain injury
Traumatic brain injury , also known as intracranial injury, occurs when an external force traumatically injures the brain. TBI can be classified based on severity, mechanism , or other features...
(TBI) in which a buildup of blood occurs between the dura mater
Dura mater
The dura mater , or dura, is the outermost of the three layers of the meninges surrounding the brain and spinal cord. It is derived from Mesoderm. The other two meningeal layers are the pia mater and the arachnoid mater. The dura surrounds the brain and the spinal cord and is responsible for...
(the tough outer membrane of the central nervous system
Central nervous system
The central nervous system is the part of the nervous system that integrates the information that it receives from, and coordinates the activity of, all parts of the bodies of bilaterian animals—that is, all multicellular animals except sponges and radially symmetric animals such as jellyfish...
) and the skull
Human skull
The human skull is a bony structure, skeleton, that is in the human head and which supports the structures of the face and forms a cavity for the brain.In humans, the adult skull is normally made up of 22 bones...
. The dura mater also covers the spine, so epidural bleeds may also occur in the spinal column. Often due to trauma
Physical trauma
Trauma refers to "a body wound or shock produced by sudden physical injury, as from violence or accident." It can also be described as "a physical wound or injury, such as a fracture or blow." Major trauma can result in secondary complications such as circulatory shock, respiratory failure and death...
, the condition is potentially deadly because the buildup of blood may increase pressure
Intracranial pressure
Intracranial pressure is the pressure inside the skull and thus in the brain tissue and cerebrospinal fluid . The body has various mechanisms by which it keeps the ICP stable, with CSF pressures varying by about 1 mmHg in normal adults through shifts in production and absorption of CSF...
in the intracranial space and compress delicate brain tissue. The condition is present in one to three percent of head injuries
Head injury
Head injury refers to trauma of the head. This may or may not include injury to the brain. However, the terms traumatic brain injury and head injury are often used interchangeably in medical literature....
. Between 15 and 20% of patients with epidural hematomas die of the injury.
Signs and symptoms
Epidural bleeds, like subduralSubdural hematoma
A subdural hematoma or subdural haematoma , also known as a subdural haemorrhage , is a type of haematoma, a form of traumatic brain injury. Blood gathers within the outermost meningeal layer, between the dura mater, which adheres to the skull, and the arachnoid mater, which envelops the brain...
and subarachnoid hemorrhage
Subarachnoid hemorrhage
A subarachnoid hemorrhage , or subarachnoid haemorrhage in British English, is bleeding into the subarachnoid space—the area between the arachnoid membrane and the pia mater surrounding the brain...
s, are extra-axial bleeds, occurring outside of the brain tissue, while intra-axial hemorrhages, including intraparenchymal
Intraparenchymal hemorrhage
Intraparenchymal hemorrhage is one extension of intracerebral hemorrhage with bleeding within brain parenchyma....
and intraventricular hemorrhage
Intraventricular hemorrhage
An intraventricular hemorrhage , often abbreviated "IVH," is a bleeding into the brain's ventricular system, where the cerebrospinal fluid is produced and circulates through towards the subarachnoid space...
s, occur within it.
After the epidural hematoma begins collecting, it starts to compress intracranial structures which may impinge on the CN III. This can be seen in the physical exam as a fixed and dilated pupil on the side of the injury.The eye will be positioned down and out due to unopposed CN VI innervation.
Other manifestations will include weakness of the extremities on the same side as the lesion due to compression of the crus on the opposite side of the lesion, and a loss of visual field opposite to the side of the lesion due to compression of the posterior cerebral artery on the side of the lesion.
The most feared event that takes place is the transtentorial, or uncal herniation which results in respiratory arrest as the medullary structures are compromised. The trigeminal nerve (CN V) may be involved late in the process as the pons becomes compressed, but this is not a significant clinical presentation since by that time the patient may already be dead.
Epidural bleeding is rapid because it is usually from arteries, which are high pressure. Epidural bleeds from arteries can grow until they reach their peak size at six to eight hours post injury, spilling from 25 to 75 cubic centimeters of blood into the intracranial space. As the hematoma expands, it strips the dura from the inside of the skull, causing an intense headache. Epidural bleeds can become large and raise intracranial pressure
Intracranial pressure
Intracranial pressure is the pressure inside the skull and thus in the brain tissue and cerebrospinal fluid . The body has various mechanisms by which it keeps the ICP stable, with CSF pressures varying by about 1 mmHg in normal adults through shifts in production and absorption of CSF...
, causing the brain to shift, lose blood supply, or be crushed against the skull. Larger hematomas cause more damage. Epidural bleeds can quickly expand and compress the brain stem, causing unconsciousness
Coma
In medicine, a coma is a state of unconsciousness, lasting more than 6 hours in which a person cannot be awakened, fails to respond normally to painful stimuli, light or sound, lacks a normal sleep-wake cycle and does not initiate voluntary actions. A person in a state of coma is described as...
, abnormal posturing
Abnormal posturing
Abnormal posturing is an involuntary flexion or extension of the arms and legs, indicating severe brain injury. It occurs when one set of muscles becomes incapacitated while the opposing set is not, and an external stimulus such as pain causes the working set of muscles to contract. The posturing...
, and abnormal pupil
Pupil
The pupil is a hole located in the center of the iris of the eye that allows light to enter the retina. It appears black because most of the light entering the pupil is absorbed by the tissues inside the eye. In humans the pupil is round, but other species, such as some cats, have slit pupils. In...
responses to light.
On images produced by CT scans and MRIs, epidural hematomas usually appear convex in shape because their expansion stops at 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 hematoma
Subdural hematoma
A subdural hematoma or subdural haematoma , also known as a subdural haemorrhage , is a type of haematoma, a form of traumatic brain injury. Blood gathers within the outermost meningeal layer, between the dura mater, which adheres to the skull, and the arachnoid mater, which envelops the brain...
. The lens like shape of the hematoma leads the appearance of these bleeds to be called "lentiform".
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 patients. In the hallmark of epidural hematoma, patients may regain consciousness during what is called a lucid interval
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...
, only to descend suddenly and rapidly into unconsciousness later. The lucid interval, which depends on the extent of the injury, is a key to diagnosing epidural hemorrhage. If the patient is not treated with prompt surgical intervention, death is likely to follow.
Causes
The most common cause of intracranial epidural hematoma is traumaticTraumatic brain injury
Traumatic brain injury , also known as intracranial injury, occurs when an external force traumatically injures the brain. TBI can be classified based on severity, mechanism , or other features...
, although spontaneous hemorrhage is known to occur. Hemorrhages commonly result from acceleration-deceleration trauma and transverse forces. 10% of epidural bleeds may be venous
Vein
In the circulatory system, veins are blood vessels 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 blood to the heart...
, due to shearing injury from rotational
Angular momentum
In physics, angular momentum, moment of momentum, or rotational momentum is a conserved vector quantity that can be used to describe the overall state of a physical system...
forces. Epidural hematoma commonly results from a blow to the side of the head. The pterion
Pterion
The pterion is the point corresponding with the posterior end of the sphenoparietal suture.-Location:It is situated about 3 cm. behind, and a little above the level of the zygomatic process of the temporal bone.It marks the junction between four bones:...
region which overlies the middle meningeal artery is relatively weak and prone to injury. Thus 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 that was impacted by the blow, but on very rare occasions it can be due to a contrecoup injury.
Treatment
As with other types of intracranial hematomas, the blood may be removed surgically to remove the mass and reduce the pressure it puts on the brain. The hematoma is evacuated through a burr hole or craniotomyCraniotomy
A craniotomy is a surgical operation in which a bone flap is temporarily removed from the skull to access the brain. Craniotomies are often a critical operation performed on patients recording, brain imaging, and for neurological manipulations such as electrical stimulation and chemical...
. If transfer to a facility with neurosurgery is prolonged trephination may be performed in the emergency department.
Prognosis
In TBI patients with epidural hematomas, prognosis is better if there was a lucid interval (a period of consciousness before coma returns) than if the patient was comatose from the time of injury. Unlike most forms of TBI, people with epidural hematoma and a Glasgow Coma Score of 3 (the lowest score) are expected to make a good outcome if they can receive surgery quickly.Of the spine
Bleeding into the epidural space in the spine may also cause epidural hematoma. These may arise spontaneously (e.g. during childbirthChildbirth
Childbirth is the culmination of a human pregnancy or gestation period with the birth of one or more newborn infants from a woman's uterus...
), or as a rare complication of anaesthesia (such as epidural
Epidural
The term epidural is often short for epidural analgesia, a form of regional analgesia involving injection of drugs through a catheter placed into the epidural space...
anaesthesia) or surgery (such as laminectomy
Laminectomy
Laminectomy is a spine operation to remove the portion of the vertebral bone called the lamina. There are many variations of laminectomy. In the most minimal form small skin incisions are made, back muscles are pushed aside rather than cut, and the parts of the vertebra adjacent to the lamina are...
).
The anatomy of the epidural space means that spinal epidural hematoma has a different profile from cranial epidural hematoma. In the spine, the epidural space contains loose fatty tissue, and the epidural venous plexus, a network of large, thin-walled veins. This means that bleeding is likely to be venous. Anatomical abnormalities and bleeding disorders
Coagulopathy
Coagulopathy is a condition in which the blood’s ability to clot is impaired. This condition can cause prolonged or excessive bleeding, which may occur spontaneously or following an injury or medical and dental procedures.The normal clotting process depends on the interplay of various proteins in...
make these lesions more likely. They may cause pressure on the spinal cord or cauda equina
Cauda equina
The cauda equina is a structure within the lower end of the spinal column of most vertebrates, that consists of nerve roots and rootlets from above...
, which may present as pain, muscle weakness, or bladder and bowel dysfunction. The diagnosis may be made on clinical appearance and time course of symptoms. It usually requires MRI scanning to confirm. The treatment is surgical decompression. The incidence of epidural hematoma following epidural anaesthesia is extremely difficult to quantify; estimates vary from 1 per 10,000 to 1 per 100,000 epidural anaesthetics.
Notable cases
Montaigne, in his essay "That to Philosophise is to Learn to Die," written in the 1580s, gives the case of his brother, Captain Saint-Martin, aged 23 years. He was playing real, or court, tennis "when he was struck by a ball a little above the right ear. There being no sign of a wound or contusion, he did not sit down to rest, but five or six hours later he died of an apoplexyApoplexy
Apoplexy is a medical term, which can be used to describe 'bleeding' in a stroke . Without further specification, it is rather outdated in use. Today it is used only for specific conditions, such as pituitary apoplexy and ovarian apoplexy. In common speech, it is used non-medically to mean a state...
caused by this blow." [from the translation by E. J. Trechmann]
On February 20, 1998, 38 year-old Indian cricketer Raman Lamba
Raman Lamba
Raman Lamba was an Indian cricketer who played in four Tests and 32 One Day Internationals, mainly as a batsman died in the Post Graduate Hospital in Dhaka in Bangladesh after three days of vain efforts by a team of doctors, ever since he was seriously hit on the forehead by a full blooded pull...
was hit on the head by a cricket ball while fielding without a helmet. Although Lamba walked off the field and the injury did not appear to be serious at the time, he succumbed to internal hemorrhage three days later.
On April 17, 2003, at age 72, Dr. Robert Atkins
Robert Atkins (nutritionist)
Robert Coleman Atkins, MD was an American physician and cardiologist, best known for the Atkins Nutritional Approach , a popular but controversial way of dieting that entails close control of carbohydrate consumption, emphasizing protein and fat intake, including saturated fat in addition to...
, creator of the Atkins diet, slipped on the ice while walking to work, hitting his head and causing bleeding around his brain. He lost consciousness on the way to the hospital, where he spent two weeks in intensive care. His death certificate states that the cause of death was "blunt impact injury of head with epidural hematoma".
On March 18, 2009, actress Natasha Richardson
Natasha Richardson
Natasha Jane Richardson was an English actress of stage and screen. A member of the Redgrave family, she was the daughter of actress Vanessa Redgrave and director/producer Tony Richardson and the granddaughter of Michael Redgrave and Rachel Kempson...
died as a result of an epidural hematoma sustained two days earlier while skiing in Mont-Tremblant
Mont-Tremblant
Circuit Mont-Tremblant is a race circuit about north of the village of Mont-Tremblant, Quebec, Canada. Formerly the village of Saint-Jovite was often included in the name but was amalgamated in 2000.-History:...
, Québec, Canada. Like many patients, she had a lucid interval where she did not exhibit any symptoms until approximately an hour after her fall when she complained of a headache. By the time she reached medical care, the hematoma had already caused significant damage.
On May 26, 2010, actor Gary Coleman
Gary Coleman
Gary Wayne Coleman was an American actor, known for his childhood role as Arnold Jackson in the American sitcom Diff'rent Strokes and for his small stature as an adult. He was described in the 1980s as "one of television's most promising stars". After a successful childhood acting career, Coleman...
was admitted to Utah Valley Regional Medical Center in Provo, Utah, after falling and hitting his head and suffering an epidural hematoma at his home in Santaquin, Utah. He was announced to be in critical condition. By mid-afternoon on May 27, 2010, Coleman was unconscious and on life support. He died at 12:05 p.m. MDT (18:05 UTC) on May 28, 2010.
External links
- MedPix: Epidural hematoma - Pictures of Epidural Hematoma
- MedPix: Epidural hematoma