Computer Vision News - April 2023

49 Edited-MRS Reconstruction not been a similar effort to speed up MRS. That is where Rodrigo and Hanna’s new challenge comes in. It explores the edited MRS modality and aims to solve the problem of hidden neurochemicals , which are difficult to study because of a low signal-to-noise ratio (SNR) . “ For edited MRS, we measure two spectra and subtract them, ” Rodrigo explains. “ Each spectrum by itself has a lot of noise compared to the signal, and then when you subtract them, you double the noise and decrease the signal even more! There simply isn’t enough signal to work with in the first place. ” Hanna adds: “ There’s this paradox: if we make the scan longer, we’re getting more data, and we’re able to reduce the SNR, but we’re increasing the chance of motion artifact. If we reduce it, we’re not collecting the signal we need. If we can accelerate it, we’re eliminating the higher probability of getting motion on the scan, which would be much better. ” Magnetic resonance spectroscopy (MRS) is an imaging modality similar to magnetic resonance imaging (MRI), but instead of looking at the anatomic structure of the brain, for example, it provides information on the chemical concentrations of neurochemicals . However, MRS has yet to reach its full potential due to issues such as a lengthy scan time that can lead to decreased spectrum quality if the subject moves. “ You want the scanner to be available to more people, but if a scan takes a long time, then doctors might not ask for it, and even researchers are going to have a hard time with it, ” Rodrigo tells us. “ There are many reasons why making it faster is beneficial for both research and clinical applications, as well as the quality of the scan itself. ” Several competitions have been designed to accelerate MRI , including one by Rodrigo and Hanna’s supervisor, Roberto Souza , but until now, there has