A Practical Guide to Virtual Autopsy: Why, When and How.

Postmortem imaging is considered a routine investigative modality in many forensic institutions worldwide. Because of its ability to provide a quick and complete documentation of skeletal system and major parenchymal alterations, postmortem computed tomography (PMCT) is the imaging technique most frequently applied in postmortem forensic investigations. Also postmortem magnetic resonance has been implemented in postmortem setting, but its use is mostly limited to focused analysis (eg, study of the heart and brain). PMCT presents some limits in investigating "natural" deaths, particularly related to its poor ability in differentiating soft tissue interfaces and in depicting vascular lesions. For this reason, PMCT angiography has been introduced. A major limitation of these postmortem imaging techniques is the absence of body samples for histopathologic, toxicologic, or microbiological analysis. This limit has been overcome by the introduction of postmortem percutaneous biopsies. The aim of this review is to provide a practical guide for virtual autopsy, with the intent of facilitating standardization and augmenting its quality. In particular, the indications of virtual autopsy as well protocols in PMCT examinations and its ancillary techniques will be discussed. Finally, the workflow of a typical virtual autopsy and its main steps will be described.