Localized Gradients in an Open Field-Cycling Low-Field MRI: First Images

Motivation: RF spatial encoding has previously been used to acquire images in our open low-field scanner1. To develop breast imaging with this device and achieve higher spatial resolution and lower scan time, localized spatial encoding cup-shaped gradients are used for spatial encoding. Goal(s): To demonstrate imaging feasibility in this non-uniform B0 field cycling magnet using localized gradients. Approach: Non-linear left-right and superior-inferior gradients are optimized on a breast imaging FOV, and a single-shot turbo spin echo pulse sequence is used. Results: The first gradient-encoded images in an open rampable nonuniform electromagnet were demonstrated. Impact: MRI has high breast cancer detection sensitivity, but due to its high cost, breast MRI is rarely conducted. By generating images with low-input-current breast-cup-shaped gradients, we show that affordable low-field MRI is a viable option for breast cancer detection.