A cerebral laceration is a type of traumatic brain injury

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...

 that occurs when the tissue of the brain is mechanically cut or torn. The injury is similar to a cerebral contusion

Cerebral contusion

Cerebral contusion, Latin contusio cerebri, a form of traumatic brain injury, is a bruise of the brain tissue. Like bruises in other tissues, cerebral contusion can be associated with multiple microhemorrhages, small blood vessel leaks into brain tissue. Contusion occurs in 20–30% of severe head...

; however, according to their respective definitions, the pia

Pia mater

Pia mater often referred to as simply the pia, is the delicate innermost layer of the meninges, the membranes surrounding the brain and spinal cord. The word finds its roots in Latin, meaning literally "tender mother." The other two meningeal membranes are the dura mater and the arachnoid mater....

-arachnoid

Arachnoid mater

The arachnoid mater, literally from Latin "spider -like mother", is one of the three meninges, the membranes that cover the brain and spinal cord...

 membranes are torn over the site of injury in laceration and are not torn in contusion. Lacerations require greater physical force to cause than contusions, but the two types of injury are grouped together in the ICD-9 and ICD-10

ICD-10

The International Statistical Classification of Diseases and Related Health Problems, 10th Revision is a medical classification list for the coding of diseases, signs and symptoms, abnormal findings, complaints, social circumstances, and external causes of injury or diseases, as maintained by the...

 classification systems.

A fifth of people with cerebral lacerations have 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...

 and no significant changes in level of consciousness. The level of consciousness decreases as the laceration bleeds and blood begins to build up within the skull.

Cerebral lacerations usually accompany other brain injuries and are often found with skull fractures on both sides of the head. Frequently occurring in the same areas as contusions, lacerations are particularly common in the inferior frontal lobe

Frontal lobe

The frontal lobe is an area in the brain of humans and other mammals, located at the front of each cerebral hemisphere and positioned anterior to the parietal lobe and superior and anterior to the temporal lobes...

s and the poles of the temporal lobe

Temporal lobe

The temporal lobe is a region of the cerebral cortex that is located beneath the Sylvian fissure on both cerebral hemispheres of the mammalian brain....

s. When associated with diffuse axonal injury

Diffuse axonal injury

Diffuse axonal injury is one of the most common and devastating types of traumatic brain injury, meaning that damage occurs over a more widespread area than in focal brain injury. DAI, which refers to extensive lesions in white matter tracts, is one of the major causes of unconsciousness and...

, the corpus callosum

Corpus callosum

The corpus callosum , also known as the colossal commissure, is a wide, flat bundle of neural fibers beneath the cortex in the eutherian brain at the longitudinal fissure. It connects the left and right cerebral hemispheres and facilitates interhemispheric communication...

 and the brain stem

Brain stem

In vertebrate anatomy the brainstem is the posterior part of the brain, adjoining and structurally continuous with the spinal cord. The brain stem provides the main motor and sensory innervation to the face and neck via the cranial nerves...

 are common locations for laceration. Lacerations are very common in penetrating and perforating head trauma

Penetrating head injury

A penetrating head injury, or open head injury, is a head injury in which the dura mater, the outer layer of the meninges, is breached. Penetrating injury can be caused by high-velocity projectiles or objects of lower velocity such as knives, or bone fragments from a skull fracture that are...

 and frequently accompany skull fracture

Skull fracture

A skull fracture is a break in one or more of the bones in the skull usually occurring as a result of blunt force trauma. If the force of the impact is excessive the bone may fracture at or near the site of the impact...

s; however, they may also occur in the absence of skull fracture. Lacerations, which may result when brain tissue is stretched, are associated with intraparenchymal bleeding (bleeding into the brain tissue).

A cerebral laceration with large amounts of blood apparent on a CT scan is an indicator of poor prognosis

Prognosis

Prognosis is a medical term to describe the likely outcome of an illness.When applied to large statistical populations, prognostic estimates can be very accurate: for example the statement "45% of patients with severe septic shock will die within 28 days" can be made with some confidence, because...

. The progression and course of complication

Complication (medicine)

Complication, in medicine, is an unfavorable evolution of a disease, a health condition or a medical treatment. The disease can become worse in its severity or show a higher number of signs, symptoms or new pathological changes, become widespread throughout the body or affect other organ systems. A...

s (health effects that result from but are distinct from the injury itself) do not appear to be affected by a cerebral laceration's location or a mass effect

Mass effect (medicine)

In medicine, a mass effect is the effect of a growing mass , for example the consequences of a growing cancer....

it causes.