Pediatric neuroimaging at 7 Tesla: towards building and validating VOPs for local SAR management in pTX

Motivation: Pediatric MRI neuroimaging has become common practice at 1.5 and 3 Tesla and we see the emergence of 7T and parallel transmission (pTX). However, today relevant local SAR prediction models are based on adult standards. Goal(s): In this work, we study the local SAR at 7T with pTX for children population (6 to 14 years old) using RF electric field simulations. Approach: We exploit a vast simulation database to build a pediatric local SAR prediction model and propose a methodology for its initial validation using convex optimization. Results: A large simulation database (above 25) is desirable to combine RF safety and pTX performance. Impact: This work aims to push pediatric MRI to ultra-high fields by developing safe SAR control for the children population. It also introduces a tool to determine appropriate safety margins to avoid excessive penalizing in the pTX pulse design.