Lung density measurement in postmortem computed tomography: a new tool to assess immediate neonatal breath in suspected neonaticides

Intro Evidence of breath after birth is one of the main forensic issues in suspected neonaticide. Hydrostatic test (HT) and pathological examination are currently used to assess it, but they are not entirely reliable or immediately available. Objective To determine the performance of postmortem computed tomography (PMCT) to assess neonatal breath in suspected neonaticide, by comparing lung CT attenuation values between live birth and stillbirth cases, in correlation with HT and pathology. Method Cases of suspected neonaticides who underwent a PMCT and complete forensic autopsy with an HT were retrospectively selected from the databases of four French Forensic Medicine Departments. The diagnosis of vitality (i.e., stillbirth or live birth) was based on the pathological examination and/or a combination of arguments, including HT result. Lung density on CT was measured in Hounsfield units (HU) by ROIs drawn in both pulmonary parenchymas. Results Eleven patients were included, six live birth and five stillbirth cases. The result of HT was concordant with pathological examination when available (seven cases). Mean lung densities in live birth cases (− 173 HU [− 255; − 91 CI 95%]) were significantly lower than in stillbirth cases (40 HU [28; 52 CI 95%]) ( p < 0.05), with a very high degree of interobserver reproducibility (ICC = 0.998 (CI 95% 0.991–0.999; p < 0.001). Conclusion PMCT and especially lung CT attenuation measurement is a reliable and easy-to-use method for assessing neonatal breath in suspected neonaticides.