Mammograms obtained with rhodium vs molybdenum anodes: contrast and dose differences

Area of Science:

• Radiology
• Medical Imaging
• Diagnostic Imaging

Background:

• Mammography utilizes different anode and filter combinations to optimize image quality and radiation dose.
• Molybdenum (Mo/Mo) and rhodium (Rh/Rh) systems are common, each with distinct characteristics.
• Evaluating these systems is crucial for patient safety and diagnostic accuracy.

Purpose of the Study:

• To compare the diagnostic performance and radiation dose of molybdenum/molybdenum (Mo/Mo) versus rhodium/rhodium (Rh/Rh) mammography systems.
• To identify patient populations that would benefit most from the Rh/Rh system's dose reduction capabilities.

Main Methods:

• A comparative study involving 100 women, with Mo/Mo mammograms of the right breast and Rh/Rh mammograms of the left breast at 26 kVp.
• Radiologists assessed mammograms from 54 women (including those with prior imaging) for breast type, preference, contrast, and sharpness.
• Mean glandular dose was calculated for both systems across different breast types.

Main Results:

• Overall preference favored the Mo/Mo combination, but Rh/Rh was preferred more often for dense breasts (types 3 and 4).
• The Rh/Rh system achieved a 42% reduction in mean glandular dose compared to Mo/Mo across all breast types.
• For a 6-cm dense breast, Rh/Rh required 40% less radiation dose than Mo/Mo.

Conclusions:

• The Rh/Rh mammography system reduces radiation dose but may decrease contrast.
• Rh/Rh mammograms can be equivalent or superior for young women and those with large, dense breasts.
• Optimal use of Rh/Rh systems necessitates patient selection based on age or breast density from prior mammograms.