Magneto-acousto-electrical tomography (MAET) is a hybrid imaging technique that combines the high spatial resolution of ultrasonography with the high contrast of electrical impedance tomography (EIT). While most previous studies on MAET have focused on twodimensional imaging, our recent research proposed a novel three-dimensional (3D) MAET method using B-mode and translational scanning. This method was the first to successfully reconstruct a 3D volume image of conductivity interfaces. However, this method has its limitations in accurately mapping irregular conductivity shapes.
To overcome this challenges, we propose a 3D magneto-acousto-electrical computed tomography (3D MAE-CT) method, utilizing an ultrasound linear array transducer. The key innovation of our method is expanding the MAE-CT method from 2D to 3D by integrating both translational and rotational scanning, similar to traditional CT techniques. The 3D MAE-CT method offers unique advantages over our previous approaches such as 2D MAE-CT or conventional 3D MAET. Compared to 2D MAE-CT, the 3D MAE-CT method reconstructs a 3D conductivity images by stacking multiple 2D MAT-CT slices, allowing for a more comprehensive representation of conductivity distribution within a volumetric space. Additionally, unlike 3D MAET, the 3D MAE-CT method excels in visualizing complex 3D conductivity volumes, effectively overcoming this inherent drawback of 3D MAET.
Phantom and in vitro experiments were conducted to evaluate the imaging quality. The results from the phantom experiments demonstrate that our method can map the 3D volume conductivity with high spatial resolution. The oblique angles extracted from the 3D image closely match practical value, with the relative error ranging from -2.80% to 4.07%. Furthermore, the in vitro experiment successfully obtained a 3D image of a chicken heart, marking the first-ever MAET 3D conductivity image of a tissue sample.