Assessment of subcalvarial hounsfield units for detecting age-related cerebral atrophy in dogs

Abstract

The objective of this study was to determine whether Hounsfield Unit (HU) measurements in the subcalvarial region can be used as an imaging indicator of cerebral atrophy in dogs. Computed tomography scans from 20 dogs aged 2–13 years were analysed, with HU values obtained at the cranial bone, immediately beneath the calvaria, and at 1 cm depth in the cerebral parenchyma. The results demonstrated significantly lower subcalvarial HU values in dogs aged ≥8 years compared to younger subjects, consistent with an age-related reduction in cerebral density and potential atrophic changes affecting brain structure. Outlier values were identified that deviated substantially from expected ranges, suggesting possible imaging artefacts, individual anatomical variation, or measurement inconsistencies, and emphasising the importance of methodological precision in HU assessment. These findings indicate that HU may have potential as a marker of cerebral atrophy in ageing dogs, contributing to the broader understanding of canine cognitive dysfunction. Validation requires larger and more diverse populations, longitudinal monitoring, and rigorous standardisation to confirm its diagnostic relevance, reproducibility, and eventual clinical applicability.