Module 5 (Early Effects of Radiation) Flashcards
(47 cards)
What are early effects of radiation exposure?
Early somatic effects occur soon after exposure to high doses of radiation, primarily from whole-body exposure (e.g., nuclear bombs, accidents).
What are the primary sources of knowledge on early effects of radiation?
Studies from nuclear bomb survivors, nuclear accident victims, laboratory animal research.
Are early effects associated with diagnostic radiography?
No, but early tissue reactions can occur in cases of prolonged fluoroscopy, excessive CT imaging, or technologist malpractice.
What are some medical imaging situations where early effects have been reported?
Prolonged fluoroscopy exams, excessive CT imaging (e.g., repeated CT stroke perfusion studies), technologist malpractice (incorrect equipment settings, inadequate knowledge).
What are the major historical sources of knowledge on radiation injury?
Early X-ray applications, Radium use in commercial products, Atomic bomb survivors (Hiroshima & Nagasaki), Nuclear power plant disasters (Chernobyl), Experimental radiation therapies
What was ‘X-ray Mania’?
The public excitement over X-ray imaging, leading to its rapid and uncontrolled use, often without shielding or exposure management.
How did early radiologists test X-ray beams?
By exposing their hands, leading to severe radiation burns and injuries.
Who first recommended radiation protection measures?
William Herbert Rollins (1898), after experiencing severe burns from X-ray exposure.
What were Rollins’ early radiation safety recommendations?
Wear protective glasses, Enclose X-ray tubes in protective housing, Limit exposure to targeted areas using radiopaque shielding.
Who was the first known death due to X-ray exposure?
Clarence Dally, an assistant to Thomas Edison, in 1904.
How was radium misused in early commercial applications?
Used in health elixirs, cosmetics, and medical treatments, believed to cure arthritis, rheumatism, high blood pressure, and insomnia.
What occupational group was heavily affected by radium exposure?
Uranium miners, who inhaled radon gas and uranium dust, leading to high lung cancer rates.
What happened to Marie Curie due to prolonged radium exposure?
She and her daughter both died of leukemia.
What event provided major data on radiation effects from high-dose exposure?
The Hiroshima and Nagasaki atomic bombings in WWII, where survivors suffered from acute and long-term radiation effects.
Why is the Chernobyl disaster significant in radiation research?
It released 30-40 times more radioactivity than the atomic bombs, leading to long-term health studies on survivors and future generations.
What early radiation therapy caused leukemia in patients?
High-dose radiation treatment for vertebral disk pain (UK, 1930s-1940s).
What radiation treatment led to thyroid tumors in patients?
Radiation exposure used to treat enlarged thymus glands in children.
How was radiation used to treat scalp ringworm, and what was the outcome?
Children were exposed to 400 rads (4 Gy), later suffering from permanent baldness in treated areas.
What is Acute Radiation Syndrome (ARS)?
ARS is a collection of early somatic effects resulting from high-dose, whole-body radiation exposure, typically observed in nuclear bomb and reactor disaster survivors.
Are early somatic effects relevant to medical imaging?
No, early effects are not associated with medical imaging but help illustrate how radiation risk increases with higher exposure.
How soon do early somatic effects appear after exposure?
Minutes to months after whole-body exposure to high doses of radiation.
What does it mean that early effects are deterministic?
Deterministic effects appear when radiation exposure exceeds a threshold, and severity increases with dose.
What are the three syndromes of ARS?
- Hematopoietic Syndrome (Bone Marrow Syndrome)
- Gastrointestinal Syndrome
- Cerebrovascular Syndrome
What radiation dose causes Hematopoietic Syndrome?
1-10 Gy whole-body exposure.
