Glossary

Abrasion: a scraping injury that carries away a surface of skin and causes bleeding.

Acute Subdural Hematoma: an arbitrarily assigned age of a subdural hematoma: usually zero to 3-4 days. There are clinical, gross, radiological and pathological characteristics for these.

Blow: force inflicted against a body, generally by another individual.

Bridging Veins: small veins that channel blood from the brain surface to the superior sagittal and other intradural venous channels that cross the subarachnoid space. Breakage or injury of these vessels causes subdural hemorrhages.

Bruise: an injury that involves some degree (usually capillary) of bleeding into a tissue (usually the skin).

CAT Scan: an image made by computed tomography.

Cause of Death: the medical cause(s) bringing about the death of an individual.

Cerebrospinal Fluid (CSF): the watery, clear fluid secreted by the choroids plexus, and probably the brain itself, that collects in the ventricles of the brain and surrounds the brain. It is produced at a constant rate at all times and must be correspondingly absorbed to maintain normal intracranial pressures.

Chronic Subdural Hematoma: an arbitrarily assigned age of a subdural hematoma: less than 10 days old (usually when a neomembrane encloses or nearly encloses a hematoma). There are clinical, gross, radiological and pathological characteristics to these.

Clinician: a physician who treats patients (internist, surgeon, pediatrician, etc.).

Coagulopathy: an abnormality of blood coagulation (either too much or too little). Can be assessed by platelet count, levels of clotting factors and other measures of blood clotting in the laboratory.

Conjunctiva: the outer covering the eyeball (the white of the eye).

Contusion: a bruise.

Cutaneous: of, relating to, or affecting the skin.

Diffuse Axonal Injuries: axonal injury that is widespread over the brain. Should have multiple samples, from different locations to document.

Ecchymosis: the escape of blood into the tissues from ruptured blood vessels. Also, a small hemorrhagic spot, larger than a petechiae, in the skin or mucous membrane forming a non-elevated, rounded or irregular, blue or purplish patch.

Edema: abnormal amounts of water that has accumulated outside vessels into the spaces between cells in an organ.

Ependyma: the cellular covering (lining) of the brain's ventricular cavities. These are ciliated low cuboidal cells that facilitate movement of cerebrospinal fluid through the ventricles.

Forensic Pathology: the medical subspecialty within pathology devoted to the medical-legal aspects of pathology. Forensic pathologists usually function as a medical examiner's pathologist and have special statutory responsibilities.

G-force: the force of gravity. Acceleration or deceleration is often expressed in Gs, representing the added "gravity" force acting on a body. If someone weighed 100 lbs. at rest, and experienced a force of 3G acceleration, they would experience the feeling of weight of 300 lbs. Tissues of the body have tolerance limits to G forces, and these limits are known.

Hematoidin: a yellow pigment not containing iron that is the product of blood degradation.

Hemosiderin: a brown-yellow pigment that contains iron and is a product of degradation of blood, usually found in scavenger cells called "sideophages."

Herniation: a breakthrough of a body organ or part of an organ through a tear or part of a membrane, muscle, or other tissue.

Hydrocephaly (Hydrocephalus): too much cerebrospinal fluid in and/or over the brain that is usually associated with increased intracranial pressure in children.

Hypoxic Ischemia: injury from lack of blood and/or oxygen to the brain. Often mistaken for diffuse axonal injury.

Hypoxia: not enough oxygen.

Impact: force directed against a body by any means (can include blow, falls and other impacts).

Infaret: dead and dying tissue due to insufficient blood or nutrient supply.

Injury: any harmful effect on any tissue in the body by any means (not meant to imply willful force necessarily).

Ischemia: not enough blood supply.

Laceration: a cutting type injury to the skin or other organ.

Lucid Interval: in psychoses or delirium, a rational period appearing in the course of the mental disorder.

Manner of Death: a quasi-legal determination stipulated by statute of how the death occurred (homicide, suicide, accident, natural disease, undetermined or judicial-execution). The Medical Examiner is empowered and required by stature to determine manner of death. Hospital pathologists generally do not determine this.

Mass Effect: damage to the brain due to the bulk of a tumor, the blockage of fluid or excess accumulation of fluid within the skull.

MRI: a noninvasive diagnostic technique that produces computerized images of internal body tissues and is based on nuclear magnetic resonance of atoms within the body induced by the application of radio waves.

Neomembrane: a membrane of inflammatory cells, reactive cells (fibroblasts), newly formed vessels and scar tissue (collagen) formed in the course of time after a subdural hemorrhage occurs. The age of this process can be estimated microscopically.

Neuropathology: the medical subspecialty of the pathology devoted to the diseases of the nervous system.

Parenchyma: working tissue of an organ, as opposed to supporting or connective tissue

Pathology: the medical specialty devoted to understanding the mechanisms, causes and manifestations of disease processes (cancer, infection, traumatic injury, toxic injury, congenital anomalies, etc.). Pathologists do autopsies, examine tissues from surgery, and use a variety of laboratory technologies and research methods. Pathologists generally do not treat patients or admit them to hospital.

Platelets: microscopic cellular elements of the blood vital to clotting.

Retina: the light-sensing element inside the eye.

Subacute Subdural Hematoma: an arbitrarily assigned age of a Subdural hematoma, usually 5-10+ days. There are clinical, gross, radiological and pathological characteristics for these.

Subarachnoid Hemorrhage: bleeding in the subarachnoid space (space normally filled with cerebrospinal fluid, below the arachnoid membrane and above the brain.

Subcutaneous: being, living, used, or made under the skin.

Subdural Hemorrhage or Hematoma: bleeding beneath the dura and above the arachnoid and brain of whatever age.

Subgaleal Hemorrhage: bleeding in the deep tissues of the scalp just above the skull.

Tentorium: a fold of the dura mater which separates the cerebellum from the cerebrum and often encloses a process or plate of the skull called the bony tentorium.

Traumatic Axonal Injuries: axonal injury due to trauma. Generally observed as focal injuries.

WBC: white blood cell count.