High-resolution imaging of substructures of the ossicles with micro-CT

Little is known about the substructure of the ossicles. With high-resolution X-ray microtomography (micro-CT), it is possible to study microstructures at high resolution without processing the specimens for histopathological examination. This pilot study was to analyse the anatomical microstructure of the incus using micro-CT. Incus specimens were taken from petrous bone preparations, fixed in formalin and examined with the μCT prototype system MetRIC of the EZRT Group/ Würzburg. With this system, a very small recording spot can be achieved by means of a special transmission tube. In addition, the system can be used very variably due to a high travel distance of the axes. Using the micro-CT a very high resolution with a voxel size of 4.1μm was achieved. In the sections, a clear accumulation of blood vessels and nutritional foramina in the centre of the incus was detected. The density of the arrangement was different between the corpus and the long as well as the short process of the incus. Towards the joints and the processes, the diameter of the vessels and nutritional foramina progressively decreased. By application of the micro-CT, a precise representation of the bone architecture and the nutritional situation was achieved. Not only the architecture of the nutritional structures but also their diameters showed an obvious difference. The examination of ossicles with micro-CT allows the analysis of the spatial relationship between surface features, internal structure and tomographic slides. Such high-resolution data can help to better understand the (patho)physiology of the middle ear and will promote the development of new middle ear prostheses or couplers.

Publication History

Article published online:
12 May 2023