Ultrasonographic densitometry of the lungs at autopsy: a preliminary investigation for possible application in forensic pathology.

The aim of the present study was to examine the possible application of ultrasonographic (US) densitometry of the lungs to quantitative evaluation of pulmonary edema at autopsy (n=85). A diagnostic ultrasound device LOGIQ alpha200 (GE Yokogawa Medical Systems) equipped with an LH probe (linear, 7.5 MHz) was used and each lobe of the lungs was scanned on the anterior and posterior surfaces after resection. The US density showed a correlation between the left and right lobes, and also between the anterior and posterior surface scans of each lobe. Although there was a correlation between the US density and combined lung weight in total cases, the density ranged very widely when lung weight was below about 1300 g, depending on the cause of death. The density was high in drowning, asphyxia, poisoning and delayed traumatic death, whereas it was usually low in fire death mainly due to burns, hemorrhagic shock and head injury. In the other causes of death, a considerable case-to-case difference was observed independent of the lung weight. These findings suggested a possible contribution of pulmonary edema to high US density, possibly depending on the survival time and irrespective of the blood contents (congestion or postmortem hypostasis).