Levels of Radiosensitivity of Organs, cells and structures of the Human Body

What does Radiosensitivity of Cells, Organs and Structures of Human body mean ?

Radiosensitivity is the relative susceptibility of cells, tissues, organs to the harmful action of radiation. It denotes the level of harm which radiation can cause to certain types of cells in the body.

We have divided into High, Intermediate and Low Radiosensitive structures of human body, and discuss the effect of radiation on various cells of human body.

Organs and Cells with High Radiosensitivity:

These organs, cells or structures are Highly susceptible to the harmful effects of radiation. And we should be aware of the harmful effects radiation can have on these before proceeding with the treatment.

1. Lymphoid organs
2. Bone marrow
3. WBC
4. Testes
5. Ovaries
6. Intestines
7. Can be Considered Relatively High: Skin and other organs with epithelial cell lining (cornea, oral cavity, oesophagus  rectum, bladder, vagina, uterine cervix, ureters)

Organs and Cells with Intermediate Radiosensitivity:

These organs, cells or structures are moderately susceptible to the harmful effects of radiation, these are neither severely affected or completely unaffected due to radiation but show moderate signs of radiation injury.

1. Optic lens
2. Stomach
3. Growing cartilage
4. Fine Vasculature
5. Growing bone
6. Kidneys
7. Liver
8. Salivary glands
9. Thyroid gland

Organs and cells with Low Radiosensitivity:

This means these organs, cells or structures are resistant to damage from radiation and are not affected by the harmful effects of radiation

1. Mature cartilage
2. RBC
3. Mature Bones
4. Respiratory organs
5. Kidneys
6. Liver
7. Pancreas
8. Thyroid
9. Adrenal gland
10. Pituitary glands
11. Muscle
12. Brain
13. Spinal cord

Reference and Notes Courtesy: Rubin, P. and Casarett – Pathology of Radiation