DOI: 10.7910/dvn/aqze3h
title: 3D optoacoustic numerical breast phantoms and simulated OAT measurement data (hemispherical shape, 4 lesions)

description: Companion dataset of the manuscript:
&lt;br&gt; Seonyeong Park, Umberto Villa, Fu Li, Refik Mert Cam, Alexander A. Oraevsky, Mark A. Anastasio, 
"&lt;b&gt;Stochastic three-dimensional numerical phantoms to enable computational studies in quantitative optoacoustic computed tomography of breast cancer&lt;/b&gt;," &lt;em&gt;J. Biomed. Opt.&lt;/em&gt; 28(6) 066002 (20 June 2023) &lt;a href="https://doi.org/10.1117/1.JBO.28.6.066002" rel="nofollow" target="_blank"&gt;https://doi.org/10.1117/1.JBO.28.6.066002&lt;/a&gt;
&lt;hr&gt;
This dataset contains 40 sets of three-dimensional (3D) numerical breast phantoms (NBPs) for use in virtual imaging trials (VITs) of optoacoustic tomography (OAT) and the corresponding simulated multi-wavelength optical fluence distributions, induced initial pressure distributions, and OAT measurement data.
The NBPs are in &lt;b&gt;&lt;em&gt;hemispherical&lt;/em&gt;&lt;/b&gt; shapes, and &lt;b&gt;&lt;em&gt;four different-sized lesions, that are composed solely of a viable tumor cell region,&lt;/em&gt;&lt;/b&gt; were inserted into each of 40 NBPs.
The NBPs correspond to one of the following four breast density types defined in Breast Imaging Reporting and Data System (&lt;a href="https://www.acr.org/Clinical-Resources/Reporting-and-Data-Systems/Bi-Rads" rel="nofollow" target="_blank"&gt;BI-RAD&#174;&lt;/a&gt;):
&lt;br&gt;
&lt;ul&gt;
 &lt;li&gt;&lt;b&gt;A&lt;/b&gt;: Breast is almost entirely fatty; &lt;/li&gt;
 &lt;li&gt;&lt;b&gt;B&lt;/b&gt;: Breast has scattered areas of fibroglandular density; &lt;/li&gt;
 &lt;li&gt;&lt;b&gt;C&lt;/b&gt;: Breast is heterogeneously dense; &lt;/li&gt;
 &lt;li&gt;&lt;b&gt;D&lt;/b&gt;: Breast is extremely dense. &lt;/li&gt;
&lt;/ul&gt;
&lt;br&gt;Each NBP set consists of
&lt;br&gt;
&lt;ol&gt;
 &lt;li&gt;A tissue label map (anatomical NBP);&lt;/li&gt;
 &lt;li&gt;Functional properties and chromophore concentrations maps (functional NBPs);&lt;/li&gt;
 &lt;li&gt;Optical properties maps (optical absorption and scattering coefficients, scattering anisotropy, and refractive indexes) at multiple illumination wavelengths (optical NBPs);&lt;/li&gt;
 &lt;li&gt;Acoustic properties (speed of sound, density, and acoustic attenuation) maps (acoustic NBPs);&lt;/li&gt;
 &lt;li&gt;Simulated multi-wavelength optical fluence distributions;&lt;/li&gt;
 &lt;li&gt;Simulated multi-wavelength induced initial pressure distributions;&lt;/li&gt;
 &lt;li&gt;Simulated multi-wavelength acoustic measurements.&lt;/li&gt;
&lt;/ol&gt;
&lt;br&gt;The tissue label map (anatomical NBP) was created by use of &lt;a href="https:GITHUB_CODE_ADDRESS" rel="nofollow" target="_blank"&gt;our adaptation&lt;/a&gt; of tools from the Virtual Imaging Clinical Trials for Regulatory Evaluation (&lt;a href="https://github.com/DIDSR/VICTRE" rel="nofollow" target="_blank"&gt;VICTRE&lt;/a&gt;) project at the U.S. Food and Drug Administration (FDA) and &lt;a href="https:GITHUB_CODE_ADDRESS" rel="nofollow" target="_blank"&gt;our python library&lt;/a&gt; to introduce blood vasculature under the skin layer.
In each NBP, four different-sized (&lt;10 mm in diameter) numerical lesion phantoms (NLPs) were inserted at locations randomly selected from those predicted by the VICTRE tools based on the duct and terminal duct lobular unit (TDLU) structures that are well-known
sites for lesion formation.
The considered tissue types and their unsigned 8-bit integer (&lt;em&gt;uint8&lt;/em&gt;) labels are as belows. 
&lt;br&gt;
&lt;ul&gt;
 &lt;li&gt;&lt;b&gt;Background&lt;/b&gt;: 0&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;Fat&lt;/b&gt;: 1&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;Skin&lt;/b&gt;: 2&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;Glandular&lt;/b&gt;: 29&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;Nipple&lt;/b&gt;: 33&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;Ligament&lt;/b&gt;: 88&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;Terminal duct lobular unit (TDLU)&lt;/b&gt;: 95&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;Duct&lt;/b&gt;: 125&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;Artery&lt;/b&gt;: 150&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;Vein&lt;/b&gt;: 225&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;Peripheral angiogenesis&lt;/b&gt;: 190&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;Viable tumor cell&lt;/b&gt;: 200&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;Necrotic core&lt;/b&gt;: 210&lt;/li&gt;
&lt;/ul&gt;
&lt;br&gt;The functional, optical, and acoustic properties maps were produced employing &lt;a href="https:GITHUB_CODE_ADDRESS" rel="nofollow" target="_blank"&gt;our python libraries&lt;/a&gt; to assign corresponding properties to each breast tissue type. 
The optical fluence distributions were simulated using the &lt;a href="https://mcx.space/wiki/index.cgi?Home" rel="nofollow" target="_blank"&gt;MCX software&lt;/a&gt; &lt;a href="https://doi.org/10.1364/OE.17.020178" rel="nofollow" target="_blank"&gt;[Fang2009]&lt;/a&gt;, &lt;a href="https://doi.org/10.1117/1.JBO.23.1.010504" rel="nofollow" target="_blank"&gt;[Yu2018]&lt;/a&gt;.
The induced initial pressure distributions were calculated via voxelwise multiplication of the optical absorption coefficient distributions and the simulated optical fluence distributions, assuming a Gr&#252;neisen &Gamma;=1 as commonly done as constant for soft tissues.
The acoustic measurements were simulated employing the &lt;a href="http://www.k-wave.org/" rel="nofollow" target="_blank"&gt;k-wave&lt;/a&gt; software &lt;a href="https://doi.org/10.1117/1.3360308" rel="nofollow" target="_blank"&gt;[Treeby2010]&lt;/a&gt;.
Further details on &lt;b&gt;1)&lt;/b&gt; &lt;em&gt;modifications and adaptations of the VICTRE NBPs for use in VITs of OAT&lt;/em&gt;; &lt;b&gt;2)&lt;/b&gt; &lt;em&gt;virtual OAT imaging system and data acquisition&lt;/em&gt; are in the accompanying paper &lt;a href="https://doi.org/DOI_NUMBER" rel="nofollow" target="_blank"&gt;[Park2023]&lt;/a&gt;. 
&lt;br&gt;
&lt;br&gt;The file naming convention of files in this dataset is &lt;b&gt;{breast type}{seed number}{lesion presence}_{contained data}.mat&lt;/b&gt;, where:
&lt;br&gt;
&lt;ul&gt;
 &lt;li&gt;&lt;b&gt;Breast type&lt;/b&gt;: &lt;b&gt;A&lt;/b&gt;, &lt;b&gt;B&lt;/b&gt;, &lt;b&gt;C&lt;/b&gt;, or &lt;b&gt;D&lt;/b&gt;;&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;Seed number&lt;/b&gt;, i.e., a number randomly generated when producing each tissue label map;&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;Lesion presence&lt;/b&gt;: absent (healthy, &lt;b&gt;h&lt;/b&gt;) or present (&lt;b&gt;l&lt;/b&gt;);&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;Contained data&lt;/b&gt;: 
 tissue label map (&lt;b&gt;label&lt;/b&gt;), 
 functional properties and chromophore concentrations maps (&lt;b&gt;func&lt;/b&gt;), 
 optical properties maps (&lt;b&gt;opt&lt;/b&gt;), 
 acoustic properties maps(&lt;b&gt;acou&lt;/b&gt;), 
 simulated optical fluence distributions (&lt;b&gt;phi&lt;/b&gt;),
 simulated induced initial pressure distributions (&lt;b&gt;p0&lt;/b&gt;), or
 simulated acoustic measurements (&lt;b&gt;p&lt;/b&gt;).&lt;/li&gt;
&lt;/ul&gt;
&lt;br&gt;For example, the file name of a tissue label map of the type A breast with no lesion inserted (healthy breast) that was created using the seed number 123456 is &lt;b&gt;A12345678h_label.mat&lt;/b&gt;.
The actual data and metadata contained in each file are as below.
&lt;br&gt;
&lt;ol&gt;
 &lt;!-- Anatomical NBP --&gt;
 &lt;li&gt;&lt;b&gt;{breast type}{seed number}{lesion presence}_label.mat&lt;/b&gt;&lt;/li&gt;
 &lt;ul&gt;
 &lt;li&gt;Data&lt;/li&gt;
 &lt;ul&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;label&lt;/em&gt;&lt;/b&gt;: 1360 x 1360 x 680 &lt;em&gt;unit8&lt;/em&gt; tissue label map that includes healthy tissues, viable tumor cell region, and necrotic core&lt;/li&gt;
 &lt;/ul&gt;
 &lt;li&gt;Metadata&lt;/li&gt;
 &lt;ul&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;origin&lt;/em&gt;&lt;/b&gt;: 3 x 1 &lt;em&gt;float32&lt;/em&gt; values that specify x, y, and z coordinates of origin, (-85, -85, -85) mm&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;voxel_size&lt;/em&gt;&lt;/b&gt;: &lt;em&gt;float32&lt;/em&gt; value that specifies voxel size, 0.125 mm&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;tissue_type_label&lt;/em&gt;&lt;/b&gt;: 13 x 2 cell that specifies tissue type names and the corresponding &lt;em&gt;uint8&lt;/em&gt; values in &lt;b&gt;&lt;em&gt;label&lt;/em&gt;&lt;/b&gt;&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;breast_type&lt;/em&gt;&lt;/b&gt;: Breast type, &lt;b&gt;A&lt;/b&gt;: Breast is almost entirely fatty; &lt;b&gt;B&lt;/b&gt;: Breast has scattered areas of fibroglandular density; &lt;b&gt;C&lt;/b&gt;: Breast is heterogeneously dense; or &lt;b&gt;D&lt;/b&gt;: Breast is extremely dense&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;lesion_presence&lt;/em&gt;&lt;/b&gt;: Lesion presence, &lt;b&gt;h&lt;/b&gt;: Lesion-absent numerical breast phantom (healthy) or &lt;b&gt;l&lt;/b&gt;: Lesion-present numerical breast phantom&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;lesion_loc&lt;/em&gt;&lt;/b&gt;: 4 x 3 &lt;em&gt;uint16&lt;/em&gt; values that specify x, y, and z locations (voxel) of four lesions in the first to fourth rows, respectively&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;unit&lt;/em&gt;&lt;/b&gt;: 3 x 2 cell that specifies units of &lt;em&gt;&lt;b&gt;origin&lt;/em&gt;&lt;/b&gt;, &lt;em&gt;&lt;b&gt;voxel_size&lt;/em&gt;&lt;/b&gt;, and &lt;b&gt;&lt;em&gt;lesion_loc&lt;/em&gt;&lt;/b&gt;&lt;/li&gt;
 &lt;/ul&gt;
 &lt;/ul&gt; 
 &lt;!-- Functional NBP --&gt;
 &lt;li&gt;&lt;b&gt;{breast type}{seed number}{lesion presence}_func.mat&lt;/b&gt;&lt;/li&gt;
 &lt;ul&gt;
 &lt;li&gt;Data&lt;/li&gt;
 &lt;ul&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;c_thbb&lt;/em&gt;&lt;/b&gt;: &lt;em&gt;float32&lt;/em&gt; value of total hemoglobin concentration (&micro;M) of blood&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;s&lt;/em&gt;&lt;/b&gt;: 1360 x 1360 x 680 &lt;em&gt;float32&lt;/em&gt; oxygen saturation map (unitless)&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;f_b&lt;/em&gt;&lt;/b&gt;: 1360 x 1360 x 680 &lt;em&gt;float32&lt;/em&gt; blood volume fraction map (unitless)&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;f_w&lt;/em&gt;&lt;/b&gt;: 1360 x 1360 x 680 &lt;em&gt;float32&lt;/em&gt; water volume fraction map (unitless)&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;f_f&lt;/em&gt;&lt;/b&gt;: 1360 x 1360 x 680 &lt;em&gt;float32&lt;/em&gt; fat volume fraction map (unitless)&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;f_m&lt;/em&gt;&lt;/b&gt;: 1360 x 1360 x 680 &lt;em&gt;float32&lt;/em&gt; melanosome volume fraction map (unitless)&lt;/li&gt;
 &lt;/ul&gt;
 &lt;li&gt;Metadata&lt;/li&gt;
 &lt;ul&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;origin&lt;/em&gt;&lt;/b&gt;: 3 x 1 &lt;em&gt;float32&lt;/em&gt; values that specify x, y, and z coordinates of origin, (-85, -85, -85) mm&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;voxel_size&lt;/em&gt;&lt;/b&gt;: &lt;em&gt;float32&lt;/em&gt; value that specifies voxel size, 0.125 mm&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;unit&lt;/em&gt;&lt;/b&gt;: 8 x 2 cell that specifies units of &lt;em&gt;&lt;b&gt;origin&lt;/em&gt;&lt;/b&gt;, &lt;em&gt;&lt;b&gt;voxel_size&lt;/em&gt;&lt;/b&gt;, &lt;b&gt;&lt;em&gt;c_thbb&lt;/em&gt;&lt;/b&gt;, &lt;b&gt;&lt;em&gt;s&lt;/em&gt;&lt;/b&gt;, &lt;b&gt;&lt;em&gt;f_b&lt;/em&gt;&lt;/b&gt;, &lt;b&gt;&lt;em&gt;f_w&lt;/em&gt;&lt;/b&gt;, &lt;b&gt;&lt;em&gt;f_f&lt;/em&gt;&lt;/b&gt;, and &lt;b&gt;&lt;em&gt;f_m&lt;/em&gt;&lt;/b&gt;&lt;/li&gt;
 &lt;/ul&gt;
 &lt;/ul&gt;
 &lt;!-- Optical NBP --&gt;
 &lt;li&gt;&lt;b&gt;{breast type}{seed number}{lesion presence}_opt.mat&lt;/b&gt;&lt;/li&gt;
 &lt;ul&gt;
 &lt;li&gt;Data&lt;/li&gt;
 &lt;ul&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;mu_a_w{757, 800, 850}&lt;/em&gt;&lt;/b&gt;: 1360 x 1360 x 680 &lt;em&gt;float32&lt;/em&gt; optical absorption coefficient maps (mm&lt;sup&gt;-1&lt;/sup&gt;) at illumination wavelengths of 757 nm, 800 nm, and 850 nm&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;mu_s_w{757, 800, 850}&lt;/em&gt;&lt;/b&gt;: 1360 x 1360 x 680 &lt;em&gt;float32&lt;/em&gt; optical scattering coefficient maps (mm&lt;sup&gt;-1&lt;/sup&gt;) at illumination wavelengths of 757 nm, 800 nm, and 850 nm&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;g&lt;/em&gt;&lt;/b&gt;: 1360 x 1360 x 680 &lt;em&gt;float32&lt;/em&gt; optical scattering anisotropy map (unitless)&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;n&lt;/em&gt;&lt;/b&gt;: 1360 x 1360 x 680 &lt;em&gt;float32&lt;/em&gt; refractive index map (unitless)&lt;/li&gt;
 &lt;/ul&gt;
 &lt;li&gt;Metadata&lt;/li&gt;
 &lt;ul&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;origin&lt;/em&gt;&lt;/b&gt;: 3 x 1 &lt;em&gt;float32&lt;/em&gt; values that specify x, y, and z coordinates of origin, (-85, -85, -85) mm&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;voxel_size&lt;/em&gt;&lt;/b&gt;: &lt;em&gt;float32&lt;/em&gt; value that specifies voxel size, 0.125 mm&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;unit&lt;/em&gt;&lt;/b&gt;: 7 x 2 cell that specifies units of &lt;em&gt;&lt;b&gt;origin&lt;/em&gt;&lt;/b&gt;, &lt;em&gt;&lt;b&gt;voxel_size&lt;/em&gt;&lt;/b&gt;, &lt;b&gt;&lt;em&gt;wavelength&lt;/em&gt;&lt;/b&gt;, &lt;b&gt;&lt;em&gt;mu_a&lt;/em&gt;&lt;/b&gt;, &lt;b&gt;&lt;em&gt;mu_s&lt;/em&gt;&lt;/b&gt;, &lt;b&gt;&lt;em&gt;g&lt;/em&gt;&lt;/b&gt;, and &lt;b&gt;&lt;em&gt;n&lt;/em&gt;&lt;/b&gt;&lt;/li&gt;
 &lt;/ul&gt;
 &lt;/ul&gt;
 &lt;!-- Acoustic NBP --&gt;
 &lt;li&gt;&lt;b&gt;{breast type}{seed number}{lesion presence}_acou.mat&lt;/b&gt;&lt;/li&gt;
 &lt;ul&gt;
 &lt;li&gt;Data&lt;/li&gt;
 &lt;ul&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;sound_speed&lt;/em&gt;&lt;/b&gt;: 1360 x 1360 x 680 &lt;em&gt;float32&lt;/em&gt; sound speed map (mm/&micro;s)&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;density&lt;/em&gt;&lt;/b&gt;: 1360 x 1360 x 680 &lt;em&gt;float32&lt;/em&gt; density map (g/mm&lt;sup&gt;3&lt;/sup&gt;)&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;alpha_coeff&lt;/em&gt;&lt;/b&gt;: 1360 x 1360 x 680 &lt;em&gt;float32&lt;/em&gt; acoustic attenuation coefficient map (dB/MHz&lt;sup&gt;y&lt;/sup&gt;mm)&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;alpha_power&lt;/em&gt;&lt;/b&gt;: &lt;em&gt;float32&lt;/em&gt; acoustic attenuation power-law exponent value (unitless)&lt;/li&gt;
 &lt;/ul&gt;
 &lt;li&gt;Metadata&lt;/li&gt;
 &lt;ul&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;origin&lt;/em&gt;&lt;/b&gt;: 3 x 1 &lt;em&gt;float32&lt;/em&gt; values that specify x, y, and z coordinates of origin, (-85, -85, -85) mm&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;voxel_size&lt;/em&gt;&lt;/b&gt;: &lt;em&gt;float32&lt;/em&gt; value that specifies voxel size, 0.125 mm&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;unit&lt;/em&gt;&lt;/b&gt;: 6 x 2 cell that specifies units of &lt;em&gt;&lt;b&gt;origin&lt;/em&gt;&lt;/b&gt;, &lt;em&gt;&lt;b&gt;voxel_size&lt;/em&gt;&lt;/b&gt;, &lt;b&gt;&lt;em&gt;sound_speed&lt;/em&gt;&lt;/b&gt;, &lt;b&gt;&lt;em&gt;density&lt;/em&gt;&lt;/b&gt;, &lt;b&gt;&lt;em&gt;alpha_coeff&lt;/em&gt;&lt;/b&gt;, and &lt;b&gt;&lt;em&gt;alpha_power&lt;/em&gt;&lt;/b&gt;&lt;/li&gt;
 &lt;/ul&gt;
 &lt;/ul&gt;
 &lt;!-- Optical fluence --&gt;
 &lt;li&gt;&lt;b&gt;{breast type}{seed number}{lesion presence}_phi.mat&lt;/b&gt;&lt;/li&gt;
 &lt;ul&gt;
 &lt;li&gt;Data&lt;/li&gt;
 &lt;ul&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;phi_w{757, 800, 850}&lt;/em&gt;&lt;/b&gt;: 680 x 680 x 340 &lt;em&gt;float32&lt;/em&gt; optical fluence distributions (mJ/mm&lt;sup&gt;2&lt;/sup&gt;) simulated based on &lt;b&gt;mu_a_w{757, 800, 850}&lt;/b&gt;, &lt;b&gt;mu_s_w{757, 800, 850}&lt;/b&gt;, &lt;b&gt;g&lt;/b&gt;, and &lt;b&gt;n&lt;/b&gt;&lt;/li&gt;
 &lt;/ul&gt;
 &lt;li&gt;Metadata&lt;/li&gt;
 &lt;ul&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;origin&lt;/em&gt;&lt;/b&gt;: 3 x 1 &lt;em&gt;float32&lt;/em&gt; values that specify x, y, and z coordinates of origin, (-85, -85, -85) mm&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;voxel_size&lt;/em&gt;&lt;/b&gt;: &lt;em&gt;float32&lt;/em&gt; value that specifies voxel size, 0.25 mm&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;unit&lt;/em&gt;&lt;/b&gt;: 4 x 2 cell that specifies units of &lt;em&gt;&lt;b&gt;origin&lt;/em&gt;&lt;/b&gt;, &lt;em&gt;&lt;b&gt;voxel_size&lt;/em&gt;&lt;/b&gt;, &lt;b&gt;&lt;em&gt;wavelength&lt;/em&gt;&lt;/b&gt;, and &lt;b&gt;&lt;em&gt;phi&lt;/em&gt;&lt;/b&gt;&lt;/li&gt;
 &lt;/ul&gt;
 &lt;/ul&gt;
 &lt;!-- Initial pressure --&gt;
 &lt;li&gt;&lt;b&gt;{breast type}{seed number}{lesion presence}_p0.mat&lt;/b&gt;&lt;/li&gt;
 &lt;ul&gt;
 &lt;li&gt;Data&lt;/li&gt;
 &lt;ul&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;p0_w{757, 800, 850}&lt;/em&gt;&lt;/b&gt;: 680 x 680 x 340 &lt;em&gt;float32&lt;/em&gt; initial pressure distributions (mJ/mm&lt;sup&gt;3&lt;/sup&gt;) calculated via voxelwise multiplication of &lt;b&gt;mu_a_w{757, 800, 850}&lt;/b&gt; and &lt;b&gt;phi_w{757, 800, 850}&lt;/b&gt; (&Gamma;=1)&lt;/li&gt;
 &lt;/ul&gt;
 &lt;li&gt;Metadata&lt;/li&gt;
 &lt;ul&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;origin&lt;/em&gt;&lt;/b&gt;: 3 x 1 &lt;em&gt;float32&lt;/em&gt; values that specify x, y, and z coordinates of origin, (-85, -85, -85) mm&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;voxel_size&lt;/em&gt;&lt;/b&gt;: &lt;em&gt;float32&lt;/em&gt; value that specifies voxel size, 0.25 mm&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;unit&lt;/em&gt;&lt;/b&gt;: 4 x 2 cell that specifies units of &lt;em&gt;&lt;b&gt;origin&lt;/em&gt;&lt;/b&gt;, &lt;em&gt;&lt;b&gt;voxel_size&lt;/em&gt;&lt;/b&gt;, &lt;b&gt;&lt;em&gt;wavelength&lt;/em&gt;&lt;/b&gt;, and &lt;b&gt;&lt;em&gt;p0&lt;/em&gt;&lt;/b&gt;&lt;/li&gt;
 &lt;/ul&gt;
 &lt;/ul&gt;
 &lt;!-- Acoustic measurements --&gt;
 &lt;li&gt;&lt;b&gt;{breast type}{seed number}{lesion presence}_p.mat&lt;/b&gt;&lt;/li&gt;
 &lt;ul&gt;
 &lt;li&gt;Data&lt;/li&gt;
 &lt;ul&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;p_w{757, 800, 850}&lt;/em&gt;&lt;/b&gt;: 51472 x 3710 &lt;em&gt;float32&lt;/em&gt; acoustic measurements (mJ/mm&lt;sup&gt;3&lt;/sup&gt;) simulated based on &lt;b&gt;sound_speed&lt;/b&gt;, &lt;b&gt;density&lt;/b&gt;, &lt;b&gt;alpha_coeff&lt;/b&gt;, &lt;b&gt;alpha_power&lt;/b&gt;, and &lt;b&gt;p0_w{757, 800, 850}&lt;/b&gt;&lt;/li&gt;
 &lt;/ul&gt;
 &lt;li&gt;Metadata&lt;/li&gt;
 &lt;ul&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;sampling_frequency&lt;/em&gt;&lt;/b&gt;: &lt;em&gt;float32&lt;/em&gt; value that specifies sampling frequency, 20 MHz&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;transducer_loc&lt;/em&gt;&lt;/b&gt;: 3 x 51472 &lt;em&gt;float32&lt;/em&gt; values that specify x, y, and z locations (mm) of virtual transducer elements in the image domain of &lt;b&gt;sound_speed&lt;/b&gt;, &lt;b&gt;density&lt;/b&gt;, &lt;b&gt;alpha_coeff&lt;/b&gt;, &lt;b&gt;alpha_power&lt;/b&gt;, and &lt;b&gt;p0_w{757, 800, 850}&lt;/b&gt;&lt;/li&gt;
 &lt;li&gt;&lt;b&gt;&lt;em&gt;unit&lt;/em&gt;&lt;/b&gt;: 4 x 2 cell that specifies units of &lt;em&gt;&lt;b&gt;sampling_frequency&lt;/em&gt;&lt;/b&gt;, &lt;em&gt;&lt;b&gt;transducer_loc&lt;/em&gt;&lt;/b&gt;, &lt;em&gt;&lt;b&gt;wavelength&lt;/em&gt;&lt;/b&gt;, and &lt;em&gt;&lt;b&gt;p&lt;/em&gt;&lt;/b&gt;&lt;/li&gt;
 &lt;/ul&gt;
 &lt;/ul&gt;
&lt;/ol&gt;
&lt;br&gt;These data were saved as MATLAB binary files version 7.3 (extension &lt;b&gt;.mat&lt;/b&gt;). They can be imported in MATLAB using the &lt;b&gt;load&lt;/b&gt; function.
&lt;br&gt;
&lt;br&gt;The code of &lt;b&gt;1)&lt;/b&gt; &lt;em&gt;our modified version of the VICTRE project by the FDA&lt;/em&gt; and &lt;b&gt;2)&lt;/b&gt; &lt;em&gt;python libraries to introduce blood vasculature under the skin layer and to assign corresponding properties to each breast tissue type&lt;/em&gt; is available from the GitHub repository: &lt;a href="https://github.com/comp-imaging-sci/breast-phantom-oat" rel="nofollow" target="_blank"&gt;comp-imaging-sci/breast-phantom-oat&lt;/a&gt;; &lt;a href="https://github.com/comp-imaging-sci/soa-nbp" rel="nofollow" target="_blank"&gt;comp-imaging-sci/soa-nbp.
&lt;br&gt;