Pneumomediastinum and soft tissue emphysema of the neck in postmortem CT and MRI; a new vital sign in hanging?
Spontaneous pneumomediastinum commonly occurs in healthy young men or parturient women in whom an increased intra-alveolar pressure (Valsalva maneuver, asthma, cough, emesis) leads to the rupture of the marginal pulmonary alveoli. The air ascends along the bronchi to the mediastinum and the subcutaneous space of the neck, causing cervico-fascial subcutaneous emphysema in 70-90% of cases. Ninety-five forensic cases, including five cases of hanging, were examined using postmortem multi-slice computed tomography (MSCT) and magnetic resonance imaging (MRI) prior to autopsy until December 2003. This paper describes the findings of pneumomediastinum and cervical emphysema in three of five cases of hanging. The mechanism of its formation is discussed based on these results and a review of the literature. In conclusion, when putrefaction gas can be excluded the findings of pneumomediastinum and cervical soft tissue emphysema serve as evidence of vitality of a hanged person. Postmortem cross-sectional imaging is considered a useful visualization tool for emphysema, with a great potential for examination and documentation.
Aghayev
Emin
E
Institute of Forensic Medicine, University of Bern, Buehlstrasse 20, 3012 Bern, Switzerland. emin.aghayev@irm.unibe.ch
Yen
Kathrin
K
Sonnenschein
Martin
M
Jackowski
Christian
C
Thali
Michael
M
Vock
Peter
P
Dirnhofer
Richard
R
D000328:Adult; D005554:Forensic Medicine; D006801:Humans; D008099:Liver / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D008478:Mediastinal Emphysema / Q000473:pathology*; D009333:Neck / Q000473:pathology; D019838:Neck Injuries / Q000473:pathology*; D013154:Spleen / Q000473:pathology; D013352:Subcutaneous Emphysema / Q000473:pathology*; D014057:Tomography, X-Ray Computed