Chapter 8 Early Tissue Reactions Flashcards
When biologic effects of radiation occur relatively soon after humans receive high doses of ionizing radiation, the biologic responses demonstrated are referred to as?
Early effects
Are effects upon the body that was it irradiated?
Somatic effects
Are effects upon future generations due to the irradiation of germ cells in previous generations?
Genetic effects
If the consequences include cell killing and are directly related to the dose received, they are called?
Somatic tissue reactions
early tissue reactions may appear within?
Minutes, hours, days, weeks
Nausea, fatigue, erythema, epilation, blood disorders, intestinal disorders, fever, dry and moist desquamation, depressed sperm count in males, temporary or permanent sterility in the male and female, injury time CNS are all examples of?
High radiation dose effects
Are caused by damage to the sensitive epithelial tissue lining the intestines.
Intestinal disorders
When whole body exposure of______ of ionizing radiation, many manifestations of organic damage occur soon after that and in succession.
6 GYt
Early tissue reactions are known as_________ syndrome?
Acute radiation syndrome
Occurs in humans after large whole body doses of ionizing radiation delivered over a short period (several hours to a few days).
Acute radiation syndrome (ARS)
Three separate dose related syndromes or conditions occurs as a part of ARS include?
Hematopoietic syndrome
Gastrointestinal syndrome
Cerebrovascular syndrome
“Bone marrow syndrome” occurs when people receive whole body doses of ionizing radiation ranging from 1 to 10 GYt
Hematopoietic syndrome
Manufacturers the corpuscular elements of the blood and is the most radio sensitive vital organ system in humans
Hematopoietic system
Death may occur 6 to 8 weeks after irradiation in some susceptible human subjects who receive a whole body dose just exceeding 2 GYt but whole body exposure dose increases from 2 to 10 GYt all irradiated individuals will die in a shorter period and with range of 1-2 GYt bone marrow cells will eventually repopulate to a level adequate to support life in most individuals.
Hematopoietic system
From _____________ people recover from 3 weeks to 6 months after irradiation.
Hematopoietic syndrome
Appears at a threshold dose of approximately 6 GYt and peaks after a dose of 10 GYt.
Gastrointestinal syndrome
Exposers personas reviewing doses of ________ may die 3 to 10 days after being exposed.
6-10 GYt
A few hours after the dose required to cause GI syndrome has been received, the _____ or beginning stage occurs. Severe ________________ persist for as long as 24 hours
Prodromal
Nausea vomiting diarrhea
for GI syndrome after the prodromal stage it is the ________which may last for several days and during this time, outward symptoms disappear then the __________ follows after stage of calm
Latent period
Manifest illness
For ________ :manifest illness a subject experiences: severe nausea vomiting diarrhea fever fatigue loss of appetite lethargy anemia leukopenia hemorrhage infection electrolyte imbalance emaciation
GI syndrome
———— occurs primarily as a result of catastrophic damage to the epithelial cells that line the GI tract.
Fatality
________ is the most severely affected part of the GI tract.
Small intestine
When the CNS and cardiovascular system receive dose of ______ GYt , _________ occurs
50
Cerebrovascular syndrome
A dose of 50 GYt can cause ______ withering a few hours to 2 or 3 days after exposure.
Death
For cerebrovascular syndrome the ________ stage happens right after irradiation and symptoms include: excessive nervousness, confusion, severe nausea, vomiting, diarrhea, loss of vision, burning sensation of skin, loss of consciousness.
Prodromal
For cerebrovascular syndrome the _______ period can last up to 12 hours and during this time symptoms lessen or disappear and then the ________ stage begins which the severe symptoms are:
Disorientation and shock, period of agitation alternating with stupor, ataxia, edema in cranial vault, loss of equilibrium, fatigue, lethargy, convulsive seizures, electrolytic imbalance, meningitis, prostration, respiratory distress, vasculitis, coma.
Latent
Manifest illness
Final result of cerebrovascular syndrome damage is the failure of the _______ which brings _____ in a matter of minutes.
CNS and cardiovascular system
Death
Term LD 50/30 signifies whole body radiation that can be lethal to 50% of the ______ within 30_______.
Population
Days
Regardless of treatment, whole body equivalent dose greater than ______ are considered fatal.
12 GYt
In repair of sublethal damage, oxygenated cells, which as a result, receive more nutrients, allow for _______ prospect or recovery than do hypoxic or poorly oxygenated cells that receive fewer nutrients.
Greater
When it comes to both categories are closed to comparable dose of low LET radiation, ______ cells are more severely damage.
Oxygenated
_______ cells do not repair and recover as efficiently.
Hypoxic
Significant cell death usually results, leading to the ______ of organs and tissues, a process referred to as ______.
Shrinkage
Atrophy
_______ organs and tissues can lose their ability to function, or may recover
Atrophied
Organ and tissue response to radiation exposure depend on factors such as:
Radio sensitivity
Reproductive characteristics
Growth rate
Tissues that suffer immediate consequences from high radiation dose include:
Skin
Male and female reproductive organs
Bone marrow
A significant reddening of the skin causes by excessive exposure to relatively low energy ionizing radiation that eventually led to cancerous lesions on the hands and finger.
Radiodermatitis
Three important safety practices for radiographers findings from Rollins:
-Radio plaque glasses
-Enclose the X-ray tube in a protective housing and irradiate only areas of interest on the patient
-Covering adjacent areas with radio plaque materials
Three layers of skin:
Epidermis (outer layer)
Dermis (middle, composed of connective tissue)
Hypodermis (subcutaneous layer of fat and connective tissue)
______ % of the body surface skin cells are replaced daily by stem cells from underlying nasal layer
2
Single absorbed dose of ____ GYt can cause radiation induced skin erythema within 24-48 hours after irradiation
2
Or shedding of the outer layer of skin, occurs at higher radiation doses
Desquamation
Generally manifests first as moist skin peeling, and then dry skin flaking may develop
Desquamation
Caused by exposure to radiation since hair follicles are growing tissue.
Epilation (alopecia)
Skin diseases such as ring worm were treated and successfully cured by irradiating the affected area with ________ (X-ray energy range of 10-20 kvp)
Grenz rays
To deliver dose to the tumor, the _______ would unavoidably be significantly greater than the tumor dose.
Skin dose
High energy gamma emitting isotopes such as cobalt 60 have historically been utilized to _______ while successfully treating non superficial cancers.
Spare skin dose
Deposit the radiant energy to an overwhelming extent into an image guided volume that both enclosed the tumor and any microscopic extent of it and includes a small added margin while delver if a substantially lower dose to as much healthy surrounding tissue as possible this is called a
Planning target volume and concept is the therapeutic ratio
Doses as low as____ can depress the male sperm population and this same dose as the potential to cause genetic mutations in future generations.
0.1 Gyt
For females, a gonadal dose of ___ may delay or suppress menstruation.
0.1 GYt
Irradiated human populations include:
Patients who have undergone radiation therapy.
Radiation accident victims
Volunteer convicts
_________, the stem cells of the testes continually reproduce. They evolve and become______. The latter cells then multiply and develop into ______ that eventually differentiate and become __________ or sperm
Spermatogonia
Spermatocytes
Spermatids
Spermatozoa
_______, the ovarian stem cells, multiply to millions of cells only during fetal development, before births, and then they steadily decline in number throughout life.
Oogonia
During latter part of fetal development, the oogonia become encapsulated by numerous _________ that grow around then. The oogonia then becomes _______ which contain follicles that are neat of cells, some of which eventually mature during reproductive life of a women.
Primordial (primary) follicles
Oocytes
As puberty begins, the developed ____ or mature female germ cells, within the follicles are ejected when the follicles themselves rupture. Usually one follicle will fully mature and more towards that surface of the ovary to be expelled and the others disintegrate.
Ova
The __________ are the most radio sensitive and the small follicles are the least radio sensitive. _______ possess only a moderate degree of radio sensitivity
Intermediate size follicles
Large mature follicles
When blood counts were used to monitor the effects of radiation exposure among those who worked with radiation,whole body radiation dose of _______ would be required to produce a measurable hematologic depression
0.25 GYt
Life spans of each type of blood cell differs varying on average from only a few hours example (_________) to almost 120 days example (_________).
Lymphocytes
Erythrocytes
Defined as the study of cell genetics with an emphasis on cell chromosomes.
Cytogenetics
Cytogenetic analysis of chromosomes may be accomplished through the use of a chromosome map called a ______.
Karyotype
Karyotype map consist of a photograph or __________ of human cell nucleus during metaphase when each chromosome can be individually perceived.
Photomicrograph
Is constructed by extracting the individual chromosomes and pairing them on the map with their sister chromosomes.
Karyotype
Is the phase of cell division in which chromosome damage caused by radiation exposure can be evaluated.
Metaphase
Majority of chromosomal damage results from the process of _______ action of ionizing radiation on vital biologic macromolecules.
Indirect
