Drowning is one of the most prevalent causes of non-natural death. According to the World Health Organisation (WHO), an estimated 360,000 annual deaths occur due to drowning.
Drowning describes the process of submersion of at least the face in a liquid medium, followed by respiratory impairment and aspiration of fluids into the respiratory tract. Drowning is, therefore, a form of asphyxia. While aspiration of fluid into the lungs, known as "wet drowning", is most common, "dry drowning" without fluid aspiration occurs in about 10-15% of cases.
Drowning presents with a number of typical but not highly specific findings 2:
- frothy foam in the nasal cavity and pharynx
- fluid in the paranasal sinuses
- found most often in the maxillary and ethmoidal sinuses followed by the sphenoidal and frontal sinuses 3
- density measurements can differentiate saltwater and freshwater contents: saltwater has a higher density (mean 47 HU) than freshwater (32 HU) 5
- fluid in the mastoid cells
- fluid in the trachea and main bronchi
ground glass opacity (GGO) in the lungs forming a mosaic pattern, which may be differentiated as 1
- reticular GGO with interstitial thickening
- patchy GGO along the airways
- (bilateral) pleural effusions 3,4
- fluid distension and increased volume of the stomach and small intestine
- the volume of the stomach has a water like density and is often layered in solid, liquid, and foam; see Wydler's sign (forensic)
- increased total lung volume and decreased radiodensity (HU) and lung density (g/l) 6
- 1. Usui, A., Kawasumi, Y., Funayama, M., Saito, H. Postmortem lung features in drowning cases on computed tomography (2014) Japanese Journal of Radiology, 32 (7), pp. 414-420.
- 2. Van Hoyweghen, A.J.L., Jacobs, W., Op de Beeck, B., Parizel, P.M. Can post-mortem CT reliably distinguish between drowning and non-drowning asphyxiation? (2014) International Journal of Legal Medicine, 129 (1), pp. 159-164.
- 3. Plaetsen, S.V., De Letter, E., Piette, M., Van Parys, G., Casselman, J.W., Verstraete, K. Post-mortem evaluation of drowning with whole body CT (2015) Forensic Science International, 249, pp. 35-41.
- 4. Christe, A., Aghayev, E., Jackowski, C., Thali, M.J., Vock, P. Drowning - Post-mortem imaging findings by computed tomography (2008) European Radiology, 18 (2), pp. 283-290.
- 5. Kawasumi, Yusuke, et al. "Distinction between saltwater drowning and freshwater drowning by assessment of sinus fluid on post-mortem computed tomography." European radiology 26.4 (2016): 1186-1190.
- 6. Leth, Peter Mygind, and Betina Hauge Madsen. "Drowning investigated by post mortem computed tomography and autopsy." Journal of Forensic Radiology and Imaging (2017).