# Enhancing Imaging Performance and Resolution in Magneto‐Acoustic Electrical Tomography With Magnetic Field Measurements (MAET‐MI) Using Figure‐of‐Eight and High‐Quality Factor Circular Coils

## TL;DR

This paper improves MAET-MI imaging by using high-quality coils and deconvolution to enhance signal quality and spatial resolution.

## Contribution

A practical method for estimating coil transfer functions and improving MAET-MI imaging through high-quality coils and 2D deconvolution.

## Key findings

- High-quality factor coils improve SNR by 12.9 dB in MAET-MI.
- 2D deconvolution with PSF enhances the spatial resolution of conductivity images.
- Combining circular and figure-of-eight coils provides comprehensive imaging coverage.

## Abstract

Magneto‐acousto‐electrical tomography with magnetic field measurement technique (MAET‐MI) is a hybrid imaging method that brings high spatial resolution of ultrasound imaging in electrical impedance tomography. This study investigates the impact of the quality factor of circular and figure‐of‐eight coils on the imaging performance of MAET‐MI. Induced MAET signals on the circular coil are accurately obtained by modeling a circuit representation of an air‐cored circular coil and deriving its transfer function through impedance measurements. The study demonstrates a significant improvement in signal‐to‐noise ratio (SNR) using high‐quality factor coils compared to unity quality factor coils. Additionally, a 16‐element linear phased array (LPA) ultrasound transducer, an air core circular coil, and a figure‐of‐eight coil are numerically modeled to obtain sector scan images of two‐dimensional conductivity distributions. Point spread function (PSF) is characterized, and the lateral resolution of sector scan conductivity images is enhanced through two‐dimensional deconvolution with PSF. The combined use of circular and figure‐of‐eight coils provides comprehensive imaging coverage. Notably, this research presents a practical method for estimating both circular and figure‐of‐eight coils' transfer functions, achieving 12.9 dB SNR improvement with high‐quality factor coils. A simplified breast model is rotated 16 steps, and sector scan conductive boundary images are reconstructed for both coils. A two‐dimensional image of a breast model is obtained by combining images from two different coils. These findings offer significant advancements in MAET‐MI imaging, particularly in low SNR environments.

This study demonstrates that high‐quality‐factor coils significantly improve the SNR in MAET‐MI imaging. A practical method is proposed to estimate the circular and figure‐of‐eight coils' transfer function and reconstruct induced signals. Additionally, spatial resolution of 2D reconstructed conductive boundary image is enhanced using 2D deconvolution with the point spread function.