Nasal ciliary motility – new tool in estimating the time of death

Introduction. Determination of time elapsed since death is one of the most difficult issues in forensic medicine. Apart from body cooling, which is widespread used in the early post-mortem interval (PMI), su- pravital reactions are the most interesting post-mortem changes upon time of death estimation. Nasal ciliary motility was occasionally ob- served in post-mortem period but nobody has studied this phenom- enon for forensic purposes. We aimed to evaluate the diagnostic use- fulness of ciliary motility as a potential tool in estimating the time of death. Methods. We obtained specimens of ciliated epithelium on 100 con- secutive cadavers (age average 71,7 years) by scraping the external portion of nasal mucosa at three different post-mortem intervals: T1 (4–6 h), T2 (10–12 h) and T3 (>16 h). The samples were then smeared on the central part of a slide and an in vitro evaluation of ciliary movement was analyzed by phase-contrast microscopy. Ciliary beat frequency (CBF) was recorded and classified as: present (3–4 beats/s), hypo-valid (1–2 beats/s) and absent. Results. Nasal ciliary motility continues after death. A statistically sig- nificant relationship between ciliary movements and increasing post- mortem interval was detected. Conclusions. Post-mortem evaluation of nasal ciliary motility is a fea- sible option for estimating the time of death. Further studies are indeed requested, however we can join the observation of such phenomenon to body cooling, and other “scientific” methods, in order to improve the reliability of the estimated PMI for forensic purposes.