Related Experiment Video
Updated: Aug 11, 2026
06:20
Irradiator Commissioning and Dosimetry for Assessment of LQ α and β Parameters, Radiation Dosing Schema, and in vivo Dose Deposition
Published on: March 11, 2021
Scatter radiation intensities about mammography units
1Department of Radiology, St. Luke's Medical Center, Milwaukee, WI 53215, USA.
Health Physics
|February 1, 1996
Summary
Scattered X-ray intensity in mammography varies with angle, with backscatter being significantly higher. Understanding scatter fraction is crucial for accurate dose estimation and radiation safety in mammographic procedures.
Area of Science:
- Medical Physics
- Radiological Imaging
- Radiation Dosimetry
Background:
- Mammography utilizes X-rays for breast cancer screening, generating scattered radiation.
- Quantifying scattered X-rays is essential for understanding image quality and patient dose.
- Previous studies have explored scatter characteristics, but detailed analysis across various angles and units is ongoing.
Purpose of the Study:
- To measure scattered X-ray intensity and scatter fraction from clinical mammographic units.
- To analyze the influence of kilovoltage peak (kVp) and scattering angle on scatter.
- To compare scatter characteristics between different mammography units and assess forward scatter dependence on equipment design.
Main Methods:
- Scattered X-ray intensity was measured at various angles (0-163 degrees) using two clinical mammographic units at 25, 30, and 35 kVp.
- Scatter fraction was calculated as the ratio of scatter dose to primary dose at 1 meter per primary X-ray field area.
- Dose to adjacent areas was estimated based on measured scatter.
Main Results:
- Backscatter (163 degrees) scatter fraction was 4-7 times greater than 90-degree scatter.
- Scatter fraction ranged from 0.01 x 10^-6 cm^-2 to 1.7 x 10^-6 cm^-2 across angles and units.
- Forward scatter showed a sharp increase around 25 degrees, dependent on image receptor and collimator design.
- Differences between units were <10% for angles >45 degrees.
Conclusions:
- Scatter fraction in mammography is highly dependent on scattering angle, particularly significant at backward angles.
- Equipment design, especially collimators and image receptors, influences forward scatter.
- The findings provide a basis for estimating radiation dose in occupied areas surrounding mammography equipment.
Related Concept Videos
02:59Biological Effects of Radiation
All radioactive nuclides emit high-energy particles or electromagnetic waves. When this radiation encounters living cells, it can cause heating, break chemical bonds, or ionize molecules. The most serious biological damage results when these radioactive emissions fragment or ionize molecules. For example, α and β particles emitted from nuclear decay reactions possess much higher energies than ordinary chemical bond energies. When these particles strike and penetrate matter, they produce ions...
01:24X-ray Imaging
German physicist Wilhelm Röntgen (1845–1923) was experimenting with electrical current when he discovered that a mysterious and invisible "ray" would pass through his flesh but leave an outline of his bones on a screen coated with a metal compound. In 1895, Röntgen made the first durable record of the internal parts of a living human: an "X-ray" image (as it came to be called) of his wife’s hand. Scientists worldwide quickly began their own experiments with X-rays, and by 1900, X-ray was widely...
01:29Positron Emission Tomography
Positron emission tomography (PET) is a medical imaging technique involving radiopharmaceuticals — substances that emit short-lived radiation. Although the first PET scanner was introduced in 1961, it took 15 more years before radiopharmaceuticals were combined with the technique and revolutionized its potential.
One of the main requirements of a PET scan is a positron-emitting radioisotope, which is produced in a cyclotron and then attached to a substance used by the part of the body being...
One of the main requirements of a PET scan is a positron-emitting radioisotope, which is produced in a cyclotron and then attached to a substance used by the part of the body being...
01:05Absorption of Radiation
The rate of heat transfer by emitted radiation is described by the Stefan-Boltzmann law of radiation:
01:30Radiological Investigation II: MRI and Ventilation Perfusion Scan
Description
Magnetic Resonance Imaging (MRI) and Ventilation Perfusion Scans are two radiological investigations that offer detailed diagnostic images of the body, particularly lung structures.
MRI
MRI uses magnetic fields and radiofrequency signals to distinguish between normal and abnormal tissues. This technology provides a more detailed diagnostic image than CT scans, enabling it to characterize pulmonary nodules, stage bronchogenic carcinoma, and evaluate inflammatory activity in...
Magnetic Resonance Imaging (MRI) and Ventilation Perfusion Scans are two radiological investigations that offer detailed diagnostic images of the body, particularly lung structures.
MRI
MRI uses magnetic fields and radiofrequency signals to distinguish between normal and abnormal tissues. This technology provides a more detailed diagnostic image than CT scans, enabling it to characterize pulmonary nodules, stage bronchogenic carcinoma, and evaluate inflammatory activity in...
01:25Imaging Studies II: Positron Emission Tomography and Scintigraphy
Positron Emission Tomography (PET) is a medical imaging technique that provides crucial insights into the body's physiological functions at a molecular level. It is an indispensable resource for diagnosing, staging, and monitoring various illnesses, notably cancer, neurological disorders, and cardiovascular conditions.
Fundamental Principles of PET
Fundamental Principles of PET