Evaluation of specific absorption rate and heating in children exposed to a 7T MRI head coil.

ABSTRACT:

Purpose

To evaluate specific absorption rate (SAR) and temperature distributions resulting from pediatric exposure to a 7T head coil.

Methods

Exposure from a 297-MHz birdcage head transmit coil (CP mode single-channel transmission) was simulated in several child models (ages 3-14, mass 13.9-50.4 kg) and one adult, using time-domain electromagnetic and thermal solvers. Position variability, age-related changes in dielectric properties, and differences in thermoregulation were also considered.

Results

Age-adjusted dielectric properties had little effect in this population. Head average SAR (hdSAR) was the limiting factor for all models centered in the coil. The value of hdSAR (normalized to net power) was found to decrease linearly with increasing mass (R²  =

SUBMITTER: Malik SJ 

PROVIDER: S-EPMC9328145 | biostudies-literature | 2022 Sep

REPOSITORIES: biostudies-literature