# Low-Cost and Easily Fabricated Ultrasound-Guided Breast Phantom for Breast Biopsy Training
###### Abstract
However, these advanced phantoms all require a much more complex fabrication process, which can involve procedures of mixing multiple materials, long preparation time, long waiting time for materials to set/cure in middle steps and high-temperature heating (180-200 \({}^{\circ}\)C). The cost of the materials needed for the advanced phantoms (USD 60 and above) is higher than turkey/chicken and gelatin-based phantoms. Commercial products are ready to use and have good contrast between background and target tissue in ultrasound imaging. However, they are very expensive and unaffordable by clinics. Moreover, they may not resemble acoustic and mechanical properties of human tissues and currently have no multilayer structure available. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Available** & **Types** & **Fabrication** & **Cost** & & **Tissue-Mimicking Capability** \\ \hline
[14; 15] & Turkey/chicken & \begin{tabular}{c} Simple but extra \\ preparation needed \\ \end{tabular} & Low & \
\begin{tabular}{c} \(\blacklozenge\) \\ • \\ \end{tabular} &
\begin{tabular}{c} Geometry is limited \\ Acoustic and mechanical properties are \\ similar but not adjustable \\ \end{tabular} \\ \hline
[12; 16; 17; 18; 19; 20; 21; 22; 23; 24] & Gelatin & Simple & Low &
\begin{tabular}{c} Acoustic and mechanical properties are \\ adjustable but not well studied \\ No various lesion types \\ No multilayer structure \\ \end{tabular} \\ \hline
[25; 26; 27] & Gelatin-agar & Complex & Medium &
\begin{tabular}{c} Can resemble acoustic and \\ mechanical properties \\ Various lesion types \\ Multilayer structure \\ \end{tabular} \\ \hline
[28] & Paraffin-gel wax & Complex & Medium &
\begin{tabular}{c} Can resemble acoustic and \\ mechanical properties \\ Various lesion types \\ Multilayer structure \\ \end{tabular} \\ \hline \hline \end{tabular}
\end{table} 
Table 1: A comparison of existing methods and commercial products of tissue mimicking breast phantom. Many phantom users have reported that the existing phantoms do not provide adequate discrimination for basic imaging characteristics (e.g., resolution and contrast resolution) [36]. The study also suggested that the existing methods and test objects remain unable to relate image quality to clinical performance. In that sense, the influence of fat is largely underestimated. Test objects do not generally show the type of artifacts that normally appear in real tissue, nor do they represent complex tissue structures [36]. Ultrasound plays a vital role in breast cancer screening and has been used to distinguish benign lesions from malignant lesions and provide guidance during interventional biopsies. Therefore, the ultrasound operator must be properly trained. This can be implemented by the use of anthropomorphic training phantoms. Gelatin-based phantoms [12; 16; 17; 18; 19; 20; 21; 22; 23; 24] have the advantages of becoming a cost-efficient solution for the needle biopsy simulation training. Their acoustic and mechanical properties are adjustable but not well investigated yet. The existing low-cost gelatin-based phantoms all have simple geometry and construction and do not represent the human breast tissue structure [12; 14; 15; 16; 17; 18; 19; 20; 21; 22; 23; 24]. Therefore, this study aims to develop a low-cost and easy-to-fabricate gelatin phantom embedded with simulated tumors that provide realistic haptic feedback. Test objects were constructed in three dimensions to obtain realistic ultrasound images. Additionally, mechanical and acoustic properties of the test objects characterized in this study are provided in this study as a reference for future research.