Early Tissue Reactions

Flashcards on Early Tissue Reactions and High-Dose Consequences of Ionizing Radiation

Early Tissue Reactions

Reactions that can appear within minutes, hours, days, or weeks after exposure to ionizing radiation, dependent on dose.

Somatic Effects

Effects upon the body that was irradiated.

Genetic Effects

Effects upon future generations due to irradiation of germ cells.

Deterministic Effects

Somatic tissue reactions that are directly related to the dose received and have consequences like cell death; they have a threshold.

Erythema

Diffuse redness of the skin; a possible high-dose consequence.

Epilation

Hair loss; a possible high-dose consequence.

Desquamation

Shedding of the outer layer of skin; can be dry or moist, and is a possible high-dose consequence.

Acute Radiation Syndrome (ARS)

Occurs in humans after large whole-body doses of ionizing radiation (6 Gyt or more) delivered over a short period of time.

Hematopoietic Syndrome

A dose-related syndrome of ARS that occurs with whole-body doses of ionizing radiation ranging from 1 to 10 Gyt, affecting bone marrow.

Gastrointestinal Syndrome

A dose-related syndrome of ARS that has a threshold dose of approximately 6 Gyt, affecting epithelial cells lining the GI tract.

Cerebrovascular Syndrome

A dose-related syndrome of ARS that occurs at doses of 50 Gyt or more to the central nervous system and cardiovascular system.

Prodromal Period

The immediate response of radiation sickness, occurring within hours after exposure.

Latent Period

The time after irradiation during which there are no signs of radiation sickness.

Manifest Illness

The period when signs and symptoms of radiation sickness return, usually more severe.

LD 50/30

Indicates the whole-body dose of radiation that is lethal to 50% of the exposed population within 30 days (approximately 3.0 to 4.0 Gyt without medical support).

LD 50/60

Indicates the whole-body dose of radiation that is lethal to 50% of the exposed population within 60 days; a more accurate measure for human survival.

Radiodermatitis

A significant reddening of the skin caused by excessive exposure to low-energy ionizing radiation.

Grenz Rays

X-rays with energies of 10 to 20 kVp, historically used to treat skin diseases.

Pluripotential Stem Cell

A single cell that determines what type of cell will develop and its function, in the hematopoietic system.

Cytogenetics

The study of cell genetics with an emphasis on chromosomes.

Karyotype

A photograph of the human cell nucleus during metaphase, used as a chromosome map.

Metaphase

The phase of mitosis in which chromosome damage from radiation exposure can be evaluated.