Forensic Pathology - postmortem investigation of sudden or unexpected death or trauma to the living

Experts Who Perform Forensic Autopsies A forensic autopsy is usually performed by a specialized medical doctor called a forensics pathologist or medical examiner. To be a pathologist, the doctor must have completed a four-year undergraduate program, four years of medical school training, and three to four years of postgraduate training in the form of a pathology residency.

Role of the Forensic Pathologist 4 broad determinations to be made: Cause of Death – medical diagnosis denoting disease or injury Mechanism of Death – altered physiology by which disease/injury produces death (arrhythmia, exsanguination) Manner of Death 1. Homicide 2. Suicide 3. Accidental 4. Natural Causes 5. Unknown D. Time of Death

Normal Postmortem Changes rigor mortis livor mortis desiccation putrefaction cell autolysis also called butyric fermentation) dry decay

Livor Mortis

Desiccation

Trauma to the Human Body Role of the Pathologist Determine type of wound Measure the dimensions (length, width, depth) Position relative to anatomical landmarks Determine initial location if wound involves cutting, slashing, etc. Determine height from heel

Types of Wounds (Trauma) Lacerations Incised Wound Puncture Abrasion Contusion Gunshot

Lacerations

Incised Wounds Slash Stab Puncture – penetrating injury due to an object with no blade

Abrasions

Contusions Color changes a bruise goes through can give rough estimate of time of injury Dark blue/purple (1-18 hours) Blue/brown (~1 to 2days) Green (~ 2 to 3 days) Yellow (~3 to 7 days) Assumes person is healthy.

Gunshot Wounds Things for pathologist to learn: type of firearm distance of gun to victim entrance vs exit wounds track of projectile

Gunshot Wounds Stippling – powder burns on the skin when the gun is inches to a few feet from the victim Starring of a contact wound – barrel touching the skin

Autopsy Steps Involved: 1. External Examination a. measurements - length, weight b. inspection of external surface for injury, discoloration, “cause of death” signs 2. Opening of Trunk a. ‘Y’ incision b. Open rib cage c. Condition of heart d. Remove organs

“Cause of Death” Petechial hemorrhage as a result of strangulation

“Cause of Death” Discoloration or bruising is noted and often hints at a “cause of death” diagnosis

Autopsy Y incision

The Y-Incision Y-Incision: The Y-Incision is the procedure used by the pathologist or examiner to open up the breastplate of the deceased and gain access to the body's major organs; heart, lungs, liver, stomach, spleen etc.

Autopsy Remove Organs: must cut ligaments holding organs in the body cavity and through the trachea and rectum transfer organ block to a dissecting table examine organs in proper order (weigh, physical exam in and out, take tissue samples, save other appropriate samples) heart  liver  spleen  kidneys  pancreas  bladder  genitalia  complete G.I. tract - save postage stamp sized amount of tissue - examine tissue under a microscope for bacteria, disease

The stomach contents must be examined as well .

Autopsy Steps Involved: Brain examination An incision is made with a “Stryker saw” from a point behind one ear, over the top of the head, to a point behind the opposite ear. The scalp is pulled away from the skull, creating tow flaps. The front flap goes over the face, the rear flap over the neck. The skull is then cut with an electric saw to create a cover that can be pulled off to expose the brain. The brain is then cut from the spinal cord and lifted out of the skull for further examination.

Finally…. Once everything has been examined, all the internal organs are returned to the body cavities or incinerated. The body is sewn back together A report will be done based on notes and findings while performing the autopsy Send tissue samples, blood, urine & etc. to lab for testing Refrigerate body to preserve it until its ready to be moved elsewhere

Interesting Facts In the 17th century, lacking chemical tests (and knowledge of disease transmission mechanisms), Italian physicians and autopsist Antonio Valsalva sometimes tasted the fluids he encountered in cadavers in an effort to better characterize them. In 1828 Irish immigrants William Burke and William Hare partnered to murder 16 people in Scotland for cadaver bounties paid for by a doctor who didn’t ask questions. Hare testified against Burke who was hung in 1829. Burkes cadaver was publicly dissected and his skeleton remains on display at the University of Edinburg. Wallets made from his skin which was stolen during the autopsy were offered for sale on the streets. In 1912, Boston physician Richard Cabot analyzed autopsies and claimed that some diseases were being misdiagnosed at an alarming rate of 80%. A 2005 study in Histopathology suggests that doctors still misdiagnose fatal diseases about a third of the time.