An open-source CT texture phantom for radiomic imaging studies: Design, manufacture, and initial evaluation

Area of Science:

• Medical Imaging
• Radiomics
• Quantitative Imaging

Background:

• Standardized reference objects are crucial for reproducible radiomic studies.
• Current phantoms lack precision, reproducibility, and accessibility for multi-center validation.
• This limits interpretability and cross-institutional comparability of imaging research.

Purpose of the Study:

• To design, manufacture, and evaluate an open-source modular CT texture phantom.
• To provide a reproducible and accessible platform for quantitative imaging research.
• To enable standardized validation of radiomic analysis.

Main Methods:

• Developed a modular phantom with an epoxy body and 3D-printed texture inserts.
• Utilized mathematically defined geometric primitives for reproducible inserts.
• Evaluated uniformity, reproducibility (ICC, CV), texture distinctness (PCA), and protocol sensitivity.

Main Results:

• High phantom body uniformity (<5 HU) and exceptional texture insert reproducibility (ICC > 0.999).
• Principal Component Analysis confirmed distinct texture stimuli from the inserts.
• Inserts showed anticipated variations in texture features across CT dose levels and reconstruction kernels.

Conclusions:

• An open-source phantom design and manufacturing approach yields high-fidelity, reproducible reference objects.
• Utilizes accessible equipment and low-cost materials for widespread adoption.
• Public domain release facilitates replication and extension, supporting standardized radiomic investigations.