Evaluating external auditory exostosis severity using ImageJ: A clinical method applied to archaeological remains

Abstract

This study aimed to evaluate if ImageJ could be used to quantify the severity of external auditory exostoses (EAEs) in archaeological human skeletal remains. Thirty-seven external auditory canals (EACs) with EAEs present (22 right, 15 left) of 100% completeness derived from individuals from archaeological sites on Cyprus dating from the Neolithic to the Roman period were available for analyses. EAC area and EAE area were measured three times as an intra-observer error test using ImageJ in a two-dimensional plane. The level of agreement between measurements was assessed using a paired T-test, Bland–Altman plot, technical error of measurement, and coefficient of reliability. No statistically significant differences were found between measurements of EAC area and EAE area and a high technical measurement of error and coefficient of reliability resulted. ImageJ can be used with a high level of reliability for quantifying the severity of EAEs. This approach enables detailed quantification of EAEs in two-dimensions, as well as specific measurement of EAE severity to evaluate differences between individuals and assemblages. The percentage of occlusion of the EAC by EAEs may contribute data to interpretations of the potential secondary clinical symptoms encountered by the individual, such as conductive hearing loss. This technique can only be applied to EACs that are of 100% preservation and in EACs where the EAEs are located laterally. Future studies should aim to incorporate the use of ImageJ for quantifying EAE severity in order to develop more detailed comparisons between individuals and assemblages in relation to their duration of exposure to wet and/or wet and windy environments and to evaluate the potential secondary symptoms that individuals with severe EAEs may have encountered.