MICROWAVE IMAGING BREAST PHANTOM, METHOD FOR TESTING RELIABILITY OF BREAST CANCER DIAGNOSTIC APPARATUS USING THE PHANTOM, AND BREAST CANCER DIAGNOSTIC APPARATUS INCLUDING THE PHANTOM

The present invention relates to a microwave imaging breast phantom including a simulated breast tissue phantom and a simulated cancer tissue phantom, wherein the simulated cancer tissue phantom is included in the simulated breast tissue phantom, the simulated breast tissue and the simulated cancer tissue are separated from each other, the simulated breast tissue and the simulated cancer tissue are formed by using a solvent solely or mixing water and a solvent, and the solvent having a range in which assuming that specific gravity of the water is a and specific gravity of the solvent is b, ‘(b−a)/a×100’ is about −10 to about +10 (wherein 0 is excluded) is mixed with the water, a method of testing reliability of a breast cancer diagnostic apparatus using the microwave imaging breast phantom, and a breast cancer diagnostic apparatus including the microwave imaging breast phantom.

DESCRIPTION OF SPECIFIC EMBODIMENTS

Hereinafter, embodiments of the present invention will be described with reference to accompanying drawings. However, the embodiments are for illustrative purposes only and are not intended to limit the scope of the invention.

A microwave imaging breast phantom in accordance with one aspect of the present invention includes a simulated breast tissue phantom and a simulated cancer tissue phantom.

The simulated breast tissue phantom has relative permittivity of about 6 to 14 and conductivity of about 0.8 to 1.8 S/m in a frequency 3 GHz, and the simulated cancer tissue phantom has relative permittivity of about 50 to 60 and conductivity of about 1 to 4 S/m in a frequency 3 GHz to 1.3 GHz.

The relative permittivity and conductivity values of breast tissue of a human being are obtained by combining the electrical characteristics of fat tissue and streamline tissue that form the breast. Furthermore, the relative permittivity and conductivity values of a real cancer tissue result from the electrical characteristics of an abnormal tissue that forms a cancer tissue.

The simulated breast tissue phantom and the simulated cancer tissue phantom that form the microwave imaging breast phantom of the present invention have very similar relative permittivity and conductivity to the breast tissue and the cancer tissue of a human being.

The microwave imaging breast phantom of the present invention is fabricated in such a manner that a simulated breast tissue and a simulated cancer tissue are respectively formed by a solvent solely or mixing water and a solvent, wherein assuming that specific gravity of water is a and specific gravity of the solvent is b, the solvent having a range in which ‘(b−a)/a×100’ is about −10 to about +10 (wherein 0 is excluded) is mixed with water, a simulated breast tissue phantom and a simulated cancer tissue phantom are formed by injecting the simulated breast tissue and the simulated cancer tissue into respective supports.

In general, in the diagnosis of breast cancer using microwave imaging, breast tissue, although not limited, is classified into four types of tissues. More particularly, breast tissue can be classified into four typical types: a breast tissue (Fatty, FT) chiefly composed of fat, a breast tissue (SCattered, SC) in which streamline tissues are scattered, a breast tissue (Heterogeneously Dense, HD) in which streamline tissues are irregularly crowded, and a breast tissue (Extremely Dense, ED) in which streamline tissues are extremely crowded.

FIGS. 3 to 6show the four types of typical breast tissues.

The above-described breast tissues typically have relative permittivity of about 6 to 14 and conductivity of about 0.8 to 1.8 S/m in a frequency 3 GHz.

The simulated breast tissue phantom of the present invention includes a simulated breast tissue formed by using a solvent solely or mixing water and a solvent. Here, assuming that specific gravity of water is a and specific gravity of the solvent is b, the solvent having a range in which ‘(b−a)/a×100’ is about −10 to about +10 (wherein 0 is excluded) is mixed with water.

The simulated breast tissue phantom of the present invention also has similar relative permittivity and conductivity in the frequency range to the four types of breast tissues.

Furthermore, real cancer tissue typically has relative permittivity of about 50 to 60 and conductivity of about 1 to 4 S/m in a frequency 3 GHz to 1.3 GHz.

In the imaging phantom of the present invention, the simulated cancer tissue phantom includes a simulated cancer tissue formed by using a solvent solely or mixing water and a solvent. Here, the solvent having a range in which assuming that specific gravity of water is a and specific gravity of the solvent is b, ‘(b−a)/a×100’ is about −10 to about +10 (wherein 0 is excluded) is mixed with water.

The simulated cancer tissue phantom of the present invention also has similar relative permittivity and conductivity in the frequency range to the real cancer tissue.

In the microwave imaging breast phantom, if a solvent having the range in which ‘(b−a)/a×100’ is less than about −10 or more than about +10 (wherein 0 is excluded) is used, a phantom cannot be formed because the solvent is not well mixed with water. Furthermore, although the solvent is mixed with water, the solvent is separated from water over time and stable electrical characteristics cannot be obtained, with the result that efficiency of microwave imaging diagnostic test equipment cannot be measured.

‘(b−a)/a×100’ preferably can be about −5 to about +5 (wherein 0 is excluded), more preferably, about 0.001 to about 5.

A solvent is not specially limited if it has the above-described physical properties for example organic or aqueous solvent. More particularly, propyleneglycol (C3H8O2, PG, specific gravity: 1.0381 g/cm3) may be used as the solvent.

In a detailed example, a simulated breast tissue can be formed by controlling a mixture ratio of water and a solvent. The four types of typical breast tissues can be formed by controlling a ratio of water and a solvent within water of about 0 to 15% and the solvent of about 85 to 100% based on content (volume). Preferably, the simulated breast tissue can be formed of a solvent of about 100%. For example, the simulated breast tissue can be formed of water of more than about 0% to about 15% and a solvent of about 85% to less than about 100%. For example, the simulated breast tissue can be formed of water of about 5 to 15% and a solvent of about 85 to 95%.

In this specification, ‘content’ means volume.

In an embodiment, a simulated FT breast tissue can be formed of a solvent of about 100% based on content (FT(PG100)). A simulated SC breast tissue can be formed by mixing a solvent of about 95% and water of about 5% based on content (SC(PG95)). A simulated HD breast tissue can be formed by mixing a solvent of about 90% and water of about 10% based on content (HD(PG90)). A simulated ED breast tissue can be formed by mixing a solvent of about 85% and water of about 15% based on content (ED(PG85)).

In the imaging phantom of the present invention, the simulated breast tissue can include one or more of the simulated FT breast tissue, the simulated SC breast tissue, the simulated HD breast tissue, and the simulated ED breast tissue.

As a result, the simulated breast tissue of the present invention has relative permittivity of about 6 to 14 and conductivity of about 0.8 to 1.8S/m in the above frequency of 3 GHz, and it can be used to test the reliability and performance of breast cancer diagnostic equipment as a common microwave imaging breast phantom.

In another detailed example, the simulated cancer tissue can be formed by controlling a mixture ratio of water and a solvent. Two types of typical cancer tissues can be formed by controlling a ratio of water and a solvent within water of about 50 to 60% and the solvent of about 40 to 50% based on content.

In an embodiment, a simulated cancer tissue can be formed by mixing a solvent of about 40% and water of about 60% based on content (a first cancer tissue, cancer(PG40)).

In another embodiment, a simulated cancer tissue can be formed by mixing a solvent of about 50% and water of about 50% based on content (a second cancer tissue).

In the microwave imaging breast phantom of the present invention, the simulated cancer tissue can include one or more of the first cancer tissue and the second cancer tissue.

As a result, the simulated cancer tissue of the present invention has relative permittivity of about 50 to 60 and conductivity of about 1 to 4 S/m in the above frequency of 3 GHz to 1.3 GHz.

The microwave imaging breast phantom of the present invention can include the simulated breast tissue phantom and the simulated cancer tissue phantom.

In a phantom, a simulated cancer tissue phantom is included in a simulated breast tissue phantom, but the simulated cancer tissue phantom and the simulated breast tissue phantom are separated from each other.

The simulated breast tissue and the simulated cancer tissue of the present invention have a liquid form, respectively. As a result, in order to shape the simulated breast tissue and the simulated cancer tissue into phantoms, the simulated breast tissue and the simulated cancer tissue are injected into the respective supports.

The support can be made of silicon, but not limited thereto.

The support can be fabricated in a membrane form by taking permeability of a microwave into consideration, but not limited thereto.

FIGS. 1 and 2are cross-sectional views showing detailed examples of the microwave imaging breast phantom in accordance with the present invention.

As shown inFIG. 1, a phantom can include a simulated breast tissue phantom120into which a simulated breast tissue has been injected within a support110for supporting the simulated breast tissue and a simulated cancer tissue phantom140into which a simulated cancer tissue has been injected within a support130for supporting the simulated cancer tissue. The simulated cancer tissue phantom140can be fixed to a specific position in the simulated breast tissue through a support pole150or can be placed at a specific position within the simulated breast tissue without a support pole.

The support pole can be made of silicon, but not limited thereto.

FIG. 1shows a phantom in which one cancer tissue phantom is included in a simulated breast tissue phantom.

However, a plurality of cancer tissues can exist within a breast tissue.

As shown inFIG. 2, a phantom can include a plurality of simulated cancer tissue phantoms140into which a simulated cancer tissue has been injected within a support130for supporting the simulated cancer tissue. The simulated cancer tissue phantom140can be fixed to specific positions in the simulated breast tissue by respective support pole150or can be scattered at specific positions within the simulated breast tissue without a support pole.

If a plurality of the simulated cancer tissue phantoms is used, a mixture ratio of a solvent and water, a form, and a size in simulated cancer tissues can be the same or different.

The imaging phantom of the present invention can be formed by combining one of the four types of breast tissues and one of the above-described cancer tissues. Furthermore, the imaging phantom of the present invention can be fabricated and used in various forms depending on the shape and size of the breast.

When fabricating the imaging phantom of the present invention, a simulated cancer tissue is fabricated and a simulated cancer tissue phantom is fabricated by injecting the fabricated simulated cancer tissue into a support. The microwave imaging breast phantom is fabricated by injecting the simulated cancer tissue phantom into a support for supporting a simulated breast tissue phantom and injecting the simulated breast tissue. The simulated cancer tissue phantom can be fixed by forming a support pole.

The results of the measurement of relative permittivity and conductivity in the same frequency domain as that ofFIGS. 7 and 8using the imaging phantom of the present invention (FT(PG100), HD(PG90), SC(PG95), FT(PG100), CANCER(PG40)) revealed that the simulated breast tissue phantom had relative permittivity of about 6 to 14 and conductivity of about 0.8 to 1.8 S/m in a frequency of 3 GHz and the simulated cancer tissue phantom had relative permittivity of about 50 to 60 and conductivity of about 1 to 4 S/m in a frequency of 3 GHz to 1.3 GHz.

As described above, it was found that a difference in the relative permittivity, that is, one of the electrical characteristics of the simulated breast tissue and the simulated cancer tissue in accordance with the present invention was about 5 to 6 times and a difference in the conductivity was about 2 to 3 times according to an increase of the frequency. As a result, whether cancer tissue exists or not the position of the cancer tissue can be easily diagnosed by measuring a reflection or scattering wave when a microwave is applied to the breast phantom.

A method of testing reliability of a breast cancer diagnostic apparatus in accordance with another aspect of the present invention includes using the microwave imaging breast phantom.

A method of diagnosing breast cancer using the microwave imaging breast phantom complies with a common method. Any breast cancer diagnostic apparatus using a microwave may be used as the breast cancer diagnostic apparatus.

The present invention can evaluate the reliability and validity of a breast cancer diagnostic apparatus by repeatedly the diagnosis of breast cancer using the microwave imaging breast phantom.

A breast cancer diagnostic apparatus in accordance with yet another aspect of the present invention includes can include the microwave imaging breast phantom.

The breast cancer diagnostic apparatus of the present invention is not specially limited to any apparatus configured to have a common microwave imaging breast phantom or the breast tissue of a human being inserted therein and to diagnose breast cancer.

For example, as shown inFIG. 9, a breast cancer diagnostic apparatus200of the present invention can include an accommodation unit220configured to accommodate a microwave imaging breast phantom210, a plurality of antennas230placed in the accommodation unit220and configured to transmit and receive electromagnetic waves, and a processing unit (not shown) connected to the accommodation unit220and configured to process information on the amplitude and phase of the electromagnetic waves received from the antennas and diagnose breast cancer based on the processed information.

More particularly, the microwave imaging breast phantom210of the breast cancer diagnostic apparatus200includes a simulated breast tissue phantom240and a simulated cancer tissue phantom250. The microwave imaging breast phantom210is accommodated within the free space260of the accommodation unit220. The plurality of antenna230for transmit and receive electromagnetic waves is disposed on the accommodation unit220, so that external electromagnetic waves can be transmitted and electromagnetic waves can be received from the microwave imaging breast phantom.

The processing unit (not shown) can process information on the amplitude and phase of electromagnetic waves received through the antennas230and diagnose breast cancer based on the processed information.

The breast cancer diagnostic apparatus200can further include sensors270attached to the inner wall of the accommodation unit220and configured to determine the size of a microwave imaging breast phantom when the microwave imaging breast phantom is received.

The breast cancer diagnostic apparatus200can further include an absorber280attached to the inner walls of the accommodation unit220and configured to reduce the scattering or interference of electromagnetic waves by absorbing electromagnetic waves emitted toward outside the phantom not the phantom.

Furthermore, the breast cancer diagnostic apparatus200can further include a motor290mounted at the bottom of the accommodation unit220and configured to move the antennas up and down.

In accordance with the phantom for breast cancer diagnostic equipment using microwave imaging according to the present invention, the simulated breast tissue phantom and the simulated cancer tissue phantom have similar electrical characteristics as real breast tissue and real cancer tissue. Accordingly, there is an advantage in that the validity and performance of breast cancer diagnostic equipment in stages prior a clinical stage. Furthermore, there are advantages in that a time problem and a cost problem can be solved because the accuracy and performance of an apparatus can be checked using the microwave imaging breast phantom in a step of developing breast cancer diagnostic equipment using microwave imaging, prior to a clinical test.