Dielectric Characterisation of Human Parathyroid Glands at Microwave Frequencies

The dielectric properties of parathyroid glands could provide valuable information for their identification, imaging and functional assessment in the field of medicine. A comprehensive understanding of these properties is crucial to the development of electromagnetic-based non-invasive or minimally invasive imaging and therapeutic techniques for improved management of parathyroid disorders. This paper reports the first comprehensive investigation of the ex vivo dielectric properties of human parathyroid glands in the microwave frequency range. An open-ended coaxial probe measurement technique was employed to measure the dielectric properties of the human parathyroid glands $(N=9)$ for a frequency range of 0.5 $-8.5$ GHz. The measurements were conducted on freshly excised human parathyroid gland samples. A two-pole Debye model was fitted on the mean dielectric properties of the human parathyroid glands. The relative permittivity values ranged from 42 - 57 over the frequency range of 0.5 GHz to 8.5 GHz, and the conductivity ranged from 0.9 - 9 S/m for that frequency band. These insights into the dielectric properties of human parathyroid glands have the potential to advance the development of microwave-based techniques for non-invasive detection, localisation and functional assessment of parathyroid glands, which will lead to improved clinical management of parathyroid-related disorders, such as hyperparathyroidism and parathyroid adenomas, through improved diagnostic accuracy and treatment planning.