A recent article published in Healthcare Technology Letters presented a soft and highly directive, proximity-coupled split-ring resonator fabricated with a liquid alloy, copper and polydimethylsiloxane (PDMS) – which had been designed for sensing osteogenesis of calvarial bone. The authors discussed that as dielectric properties of bone grafts in ossifying calvarial defects should change during the osteogenesis process, these devices could monitor the gradual transformation of the defect into bone by differentiating changes in the dielectric properties as shifts in the resonance frequency. It was stated that Computational Software Technology (CST) Microwave Studio-based simulation results on computational head models were in good agreement with laboratory results on head phantom models—which also included the comparison with an in-vivo measurement on the human head.

This article stated that since the skin elasticity of newborn children is high, stretching and crumpling could be significant. Furthermore, due to typical head curvatures in newborn children, bending should not be a significant issue and can provide higher energy focus in the defect area and improve conformability.

It was summarized that the present concept could support the development of soft, cheap and portable follow-up monitoring systems to use in outpatient hospital and home care settings for post-operative monitoring of bone healing after reconstructive surgical procedures.

Source: Healthcare Technology Letters. 2020 Feb 17;7(1):29-34. doi: 10.1049/htl.2018.5083.