Brain tissue equivalent material and phantom device comprising the same

1. A composition comprising:

1-4% glass micro bubbles (w/w);

60-80% (w/w) epoxy wherein the epoxy components are present in a 10:4 to 1:1 ratio of resin to polyamine or anhydride;

3-5% CaCO 3 (w/w);

1-3% MgO(w/w);

9-13% Polyethylene (w/w)

3-7% Acrylic Micro Spheres (w/w); and

0-1% Pigment.

2. The composition of claim 1 , for use in radiographic calibration and quality assurance, wherein the concentration of glass micro bubbles is 1.6-3.6% (w/w) and the 60-80% (w/w) epoxy consists of:

50-63% Araldite (w/w); and

18-24% Jeffamine (w/w).

3. The composition of claim 1 , wherein the elemental composition comprises:

Hydrogen at a concentration of 8-9% (w/w);

Carbon at a concentration of 67-68% (w/w);

Nitrogen at a concentration of 1-2% (w/w);

Oxygen at a concentration of 20-21% (w/w);

Chlorine at a concentration of less than 1% (w/w);

Calcium at a concentration of less than 1% (w/w); and

Silicon at a concentration of less than 1% (w/w).

4. The composition of claim 1 , wherein the composition comprises at least one of boron, sodium or a combination thereof.

5. The composition of claim 4 , wherein the boron is at a concentration of less than 1% (w/w) and the sodium is at a concentration of less than 1% (w/w).

6. The composition of claim 1 , wherein the composition consists of:

8.56% Hydrogen;

67.46% Carbon;

1.85% Nitrogen;

20.52% Oxygen;

0.11% Chlorine;

0.75% Calcium;

0.64% Silicon;

0.02% Boron; and

0.1% Sodium.

7. The composition of claim 1 , wherein the composition has a physical density of between 1.045 g/cm 3 and 1.055 g/cm 3 .

8. The composition of claim 1 , wherein the composition is a brain tissue phantom.

9. The composition of claim 1 , wherein the composition mimics radiographic attenuation of brain tissue within ±5 HU for X-ray energies between 40 keV and 140 keV.

10. The composition of claim 9 , wherein the composition mimics radiographic attenuation of brain tissue with ±1 HU for X-ray energies between 40 keV and 140 keV.

11. The composition of claim 1 , wherein the epoxy resin is selected from Araldite, trimethylhexamethylenediamine, Epoxide No. 7, Epikote and combinations thereof and the hardener is selected from Jeffamine, Synolide, aminohexanes, polyoxypropylenetriamines or combinations thereof.

12. A method of calibrating a radiographic device for imaging of brain tissue, the method comprising:

providing a phantom with a brain equivalent material comprising the composition of claim 1 ;

aligning the phantom with the radiographic device;

measuring an attenuation of X-rays by the brain equivalent material; and

calculating a device specific correction factor for the radiographic device from the measured attenuation of the X-rays and a known electron density for the brain equivalent material.

13. The method of claim 12 , further comprising repeating the measurement of the attenuation of the X-rays at a plurality of X-ray energies.

14. The method of claim 12 , wherein the plurality of X-ray energies are between 40 keV and 140 keV.

15. The method of claim 13 , wherein the phantom comprises a plurality of tissue equivalent materials, and further comprising:

measuring an attenuation of the X-rays by each of the plurality of tissue equivalent materials;

plotting the measured attenuations of the X-rays by the tissue equivalent materials and the brain equivalent material against known electron densities for the plurality of tissue equivalent materials and the brain equivalent material; and

wherein the device specific correction factor is calculated from the measured attenuations and the known electron densities.

16. The method of claim 12 , wherein the brain equivalent material is the composition of claim 6 .

17. The method of any one of claims 12 , further comprising applying the device specific correction factor to radiographic images acquired by the radiographic device.

18. A composition comprising:

1-4% glass micro bubbles (w/w);

60-80% (w/w) epoxy wherein the epoxy components are present in a 10:4 to 1:1 ratio of resin to polyamine or anhydride;

3-5% CaCO 3 (w/w);

1-3% MgO(w/w); and

9-13% Polyethylene (w/w)

wherein the composition consists of:

8. 56% Hydrogen;

67. 46% Carbon;

1. 85% Nitrogen;

20. 52% Oxygen;

0.11% Chlorine;

0.75% Calcium;

0.64% Silicon;

0.02% Boron; and

0.1% Sodium.