Low-Dose Contrast-Enhanced Breast CT Using Spectral Shaping Filters: An Experimental Study

Area of Science:

• Medical Imaging
• Radiological Physics
• Biomedical Engineering

Background:

• Contrast-enhanced X-ray imaging of the breast is crucial for diagnosis.
• Dedicated breast CT offers advantages like no compression and 3D imaging but requires dose reduction for clinical viability.

Purpose of the Study:

• To investigate spectral shaping using high atomic number filters (Gd, Er) for reducing radiation dose in contrast-enhanced breast CT.
• To compare the dose efficiency of Gd and Er filters against traditional Al and Cu filters.

Main Methods:

• A benchtop breast CT system emulating clinical settings was used.
• A phantom with iodine inserts was imaged to assess task-based performance.
• A channelized hoteling observer (CHO) with Laguerre-Gauss channels evaluated detectability.

Main Results:

• Spectral shaping with Er and Gd filters substantially increased dose efficiency compared to standard filters and settings.
• Dose efficiency was defined as the signal-to-noise ratio of the CHO divided by mean glandular dose.

Conclusions:

• Erbium and gadolinium filters show significant potential for improving dose efficiency in breast CT.
• Further clinical evaluation in patients is necessary to validate these findings for routine use.