Evaluation of the in vivo performance of a...

Evaluation of the in vivo performance of a 109Cd-based x-ray fluorescence system for measurement of skin iron concentration

Abstract

Abstract There are many diseases associated with iron deficiency and iron overload prevalent in the Canadian population, however, there are no rapid, cost-effective, non-invasive methods of measuring iron. X-ray fluorescence (XRF) is a non-invasive means of quantifying iron in the body. Here we present the results from a preliminary in vivo measurement study using a novel 109Cd-based XRF system for the measurement of skin iron. In vivo XRF measurements of the thenar eminence of the hand were performed on 12 female and 12 male participants between 18 and 76 years of age. Participants had no known iron-associated diseases. The mean (median) in vivo measurement uncertainty was 2.0 µg Fe /g resulting in an in vivo detection limit of 4.0 (4.0) µg Fe /g, with a 95% confidence upper interval of 4.2 µg Fe /g. The mean (median) estimate of skin iron was 9.0 (9.1) µg Fe /g with a range of 3 to 17 µg Fe /g, matching reported levels in the literature. Iron concentrations were correlated with age (p= 0.019, R2= 0.19) with iron increasing by 2 ±1 % per annum.Individual estimates of iron skin content were all greater than zero at the 95% confidence level. No differences in measurement uncertainty were observed across age and gender (p > 0.05). However, the increase in skin iron with age meant there was greater confidence that iron levels were greater than zero in older adults. The 109Cd K XRF system was therefore found to be feasible for in vivo measurement of skin iron in this small population of healthy adults.