A post mortem (or autopsy) is ordered by the Coroner to ensure that he or she can deliver a balanced, accurate finding regarding the cause of death. A post mortem is a detailed examination of the body by a doctor who has special training and experience in this field.
During the postmortem, all parts of the body undergo a detailed inspection to determine the presence, nature and extent of any disease or damage. This inspection requires that all organs be removed from the body and examined. Small samples of tissue are taken from individual organs and are usually retained forever. The reason for keeping the samples is to ensure that any questions that may arise months, or years after death, can be answered by further examination, perhaps by new techniques that were not available at the time of the initial post mortem examination.
In some cases, whole organs may have to be retained for an extended period of time to detect finer details of disease or damage. This is especially true of parts of the nervous system such as the brain. Organ retention tends to occur when the initial post mortem examination does not provide adequate information or where the cause of death can only be verified following further microscopic study of the organs. This pathology can take a number of weeks to complete. During the post mortem exam, the forensic pathologist will determine whether these test are required.