# T2‐Weighted Imaging of Water, Fat and Silicone

## TL;DR

This paper introduces a new MRI technique that quickly and accurately separates water, fat, and silicone in breast imaging, working for patients with or without implants.

## Contribution

A single MRI sequence that enables T2-weighted imaging and separation of water, fat, and silicone in clinically feasible time.

## Key findings

- A 2D FSE sequence with multi-echo readouts enables field mapping and species separation.
- Joint multi-echo reconstruction with incoherent ky–TE sampling achieves R=6 acceleration and 2.5-minute scan time.
- The method produces high-resolution, artifact-free images across three planes for various implant types.

## Abstract

Magnetic resonance imaging (MRI) is a sensitive method for assessing silicone implant integrity, with T2‐weighted imaging being essential for detecting abnormalities in surrounding tissue. Silicone breast imaging protocols often require multiple tailored sequences for species suppression and diagnostic contrast. We propose a single sequence suitable for patients with or without implants that enables T2‐weighted, high‐quality imaging and three‐species separation within a clinically feasible scan time.

Our approach uses a 2D fast spin echo (FSE) sequence with seven bipolar multi‐echo gradient echo readouts, enabling field mapping and water–fat–silicone separation. Incoherent ky–TE undersampling combined with joint multi‐echo reconstruction leverages temporal correlations and applies compressed sensing regularization directly to the separated species.

We achieve high‐resolution, artifact‐free water, fat, and silicone (WFS) images across three planes from one sequence, regardless of shim quality, and for different breast implant types. Compared to independent echo reconstruction and separation, joint multi‐echo reconstruction with incoherent ky–TE sampling allows acceleration of R=6, reducing scan time to 2.5 minutes.

We demonstrate a robust T2‐weighted technique that provides reliable water–fat–silicone imaging in 2.5 minutes, enabling uniform breast protocols for patients with and without silicone implants.