Introduction to Forensic Pathology course

forensic pathobiology introduction

1. Introduction to
forensic
pathology
Dr. Maliha Khara MD, FRCPC
Forensic pathologist, Ontario Forensic Pathology Service
Lecturer, Department of Laboratory Medicine and
Pathobiology, University of Toronto

2. OUTLINE
Course overview
The Forensic AUTOPSY
CLASSIC autopsy pathology
Postmortem CHANGES

3. LMP415
Dr. Maliha Khara:
[email protected]
Teaching Assistant: Evan
Lubanszky
[email protected]

4. SYLLABUS

5. MARKS
DISTRIBUTION
Mid-term exam 50% -
short and long answer
format.
Final exam 50%-during
spring exam period

6. RECOMMENDED
REFERENCES
There is no required text, however we recommend
following standard textbooks as references:
1. Robbins and Cotran Pathological Basis of
Disease
2. Forensic Pathology, DiMaio and DiMaio
3. Knight’s Forensic Pathology
4. Simpson’s Forensic Medicine

7. FORENSICS
•Forensic science: the application of a broad spectrum of
sciences to answer questions of interest to the legal
system.
•Criminal or civil matters
•From Latin “forensis” of or before the forum
•In Roman times a case involving a criminal charge had to
presented before the public in the forum –by the accused
and the accuser
•Modern usages of word forensic = as a form of legal
evidence and as a category of public presentation

8. BRANCHES OF
FORENSIC SCIENCE
•FORENSIC ANTHROPOLOGY: application of physical
anthropology in a legal setting, usually for the recovery and
identification of skeletonized human remains.
•FORENSIC ENTOMOLOGY:examination of insects in, on,
and around human remains to assist in determination of
time or location of death. It is also possible to determine if
the body was moved after death.

9. BRANCHES OF
FORENSIC SCIENCE
•FORENSIC ODONTOLOGY: dentistry focused on
identification of deceased.
•FORENSIC PSYCHIATRY: application of principles of
psychiatry to matters of the law; determination of
competency to stand trail
•FORENSIC TOXICOLOGY is the study of the effect of drugs
and poisons on/in the human body.
•CLINICAL FORENSIC MEDICINE –use of medical knowledge
to answer legal questions.
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10. BRANCHES OF
FORENSIC SCIENCE
FORENSIC PATHOLOGY
•The study of disease and injury in a legal context
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medicine and pathology are applied to determine a cause of
death or injury in the context of a legal inquiry.

12. FORENSICS
PATHOLOGISTS
•What do we do?
•Perform autopsies
•Write reports
•Testify in court
•Teach
•Research
•Administration
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dothen

13. WHAT IS AN
AUTOPSY?
•A surgical procedure that consists
of a thorough examination of a
corpse by dissection to determine
the cause, mechanism, and
manner of death or to evaluate
any disease or injury
•“To see for oneself”
hospital
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14. 2 TYPES OF AUTOPSIES
1.Non-medicolegal
xHospital/family permitted
2.Medicolegal autopsies
xForensic
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15. WHAT IS A HOSPITAL
AUTOPSY?
•A professional consultation with
the provision of an opinion
regarding the cause of death.
•Performed to diagnose or
determine extent of disease or
effects of therapy
•Requires family consent

16. WHAT IS A
MEDICOLEGAL
(FORENSIC)
AUTOPSY?
•Warranted by coroner or medical examiner as
authorized by law with the statutory purpose of
establishing the cause of death and answer other
medicolegal questions.
•The next of kin do not authorize this
•Conducted to answer questions of interest for:
Coroners
Judiciary
Public
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17. WHAT IS A
MEDICOLEGAL
(FORENSIC)
AUTOPSY?
•A forensic autopsy is part of an
investigation on behalf of society to
determine how and why its citizens die.
•In Ontario such investigations are
conducted by:
•Office of the Chief Coroner (OCC)
•Ontario Forensic Pathology Service
(OFPS)
•Both the OCC and the OFPS reside within
the Ministry of the Solicitor General
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18. OFPS and the Goudge
Inquiry
•Created in 2009
•Resulted from recommendations of Goudge Inquiry
•There are 6 Regional Forensic Pathology Units in
Ontario, including Toronto, Ottawa, Kingston,
London, Sudbury and Sault Ste. Marie. These units
provide expertise in forensic pathology for
approximately 10,000 routine and complex
autopsies annually.
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19. FORENSIC
PATHOLOGIST
VS CORONER
•Medical Subspecialist
•Experts in disease and injury
•After medical school 5 years
of training in AP (medical
specialty)
•One year fellowship FP
•Practice full time:
•Performing autopsies,
•Testify as medical expert
•Give opinion as to COD
•Any physician
•Usually part-time job for
family doctor
•Some training
•Investigate death: go to
scene, gather information,
warrants PM
•Not an expert, does not do
PMs, does not testify
•Write a report after
receive our report

20. Dr. Dirk Huyer, Chief Coroner Dr. Michael Pollanen, Chief Forensic Pathologist

21. Warrant for
Postmortem
examination

22. Who gets AN
AUTOPSY?
Anyone who dies:
•Suddenly
•Unexpectedly
•Homicide
•Suicide
•Accident
•Suspicious circumstances
•In custody
•On job site
•Coroner’s Act
don't
matterwhat
kind
in
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other
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getone

23. Objectives of an
autopsy
•Identification
•Trace evidence collection
•Documentation –injuries, findings
•Determine COD
•Determine the MOD
•Liaison with other agencies
•Testify in court
er
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24. FIVE PARTS OF THE MEDICOLEGAL AUTOPSY
Assessment of the SCENE & CIRCUMSTANCES surrounding the death
EXTERNAL examination of the body
INTERNAL examination of the body
Interpretation of ANCILLARY STUDIESfor the case
Synthesis of a MEDICOLEGAL OPINION
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02
03
04
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25. EXAMINATION OF
THE SCENE &
CIRCUMSTANCES
•Dependent on INITIAL police
investigation
•Coroner’s WARRANT
•Police REPORT
•Conversations with INVESTIGATING
OFFICER(s)
•Scene PHOTOGRAPHS
•Scene VISIT
•Medical RECORDS/AMBULANCE CALL
REPORT

26. EXTERNAL
EXAMINATION
•IDENTIFICATION
•GENERAL NUTRITION &
DEVELOPMENT
•Examine all body surfaces
•Documentation of INJURIES,
PETECHIAE, etc.
•Collection of TRACE EVIDENCE
•Consider ALTERNATE LIGHT SOURCE
examination
•Consider RADIOGRAPHICexamination
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career
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identifed
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cases
behraisizinjuries
boinOntariohmafullbodyCt
scan
andMRI

27. INTERNAL
EXAMINATION
•Opening of cranial, thoracic and abdominal
cavities
•Standard Y incision
•Examination of all organs inand ex-situ
•System wise documentation (gross)
•Special dissections
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Occully
limb
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stab
meds

28. ANCILLARY TESTS
besLodology

29. ANCILLARY TESTS

30. MEDICOLEGAL
SUMMARY & OPINION
The AUTOPSYis an INTEGRATIONof all
information available and must be
interpreted in the specific context of the
case.
Injuries/findings rarely stand alone.

31. AUTOPSY REPORT
1.History
2.Authorization
3.Identification
4.External examination
5.Internal examination
6.Ancillary Tests
7.Summary of findings and opinion
8.COD
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reviewepids
homicides

32. AUTOPSY REPORT
•Remember the autopsy is an integration of all information availableand
interpreted from within a context.
Common misconception:
•“All is revealed when one opens the body and dissects the organs.”

33. OPINION
FORMATION
INVOLVES
DETERMINING…
•Immediate cause of death
•Underlying cause of death (COD)
•Contributing factors

34. CAUSE OF
DEATH
Definition:
Disease or injury that produces the physiological
disruption in the body resulting in the death.
Examples?
GSW TO HEAD
STAB WOUND OF CHEST

35. CAUSE OF DEATH
•Example:
•56 y.o. man suddenly clutches chest, in
pain and shortly after dies
•COD:
•ACUTE MYOCARDIAL INFARCTION due
to CORONARY ATHEROTHROMBOSIS



CAUSE OF DEATH

Part I: Immediate cause of death and antecedent causes, if any, giving rise to the
immediate cause (a).

(a)
DUE TO (OR AS A CONSEQUENCE OF)
(b)
DUE TO (OR AS A CONSEQUENCE OF)
(c)
Part II: Other significant conditions contributing to the death but not causally related to
the immediate cause (a).




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atted
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36. THE
TRIANGLE
OF DEATH
Natural
Disease
ToxicologyTrauma
CODMost
CODSinthe3

37. CAUSE
OF
DEATH -
CLASSES
Definitively fatal acute pathologic finding(s) are identified that
imply the cause of death, based on clinicopathologic correlation
with the history and exclusionary findings
Potentially fatal acute pathologic finding(s) are identified that
imply the cause of death, based on clinicopathologic correlation
with the history and exclusionary findings.
Potentially fatal chronicpathologic finding(s) are identified that
imply the cause of death, based on clinicopathologic correlation
with the history and exclusionary findings.
Non-definitive or non-specific pathologic findings are present
that can explain death based on inference from clinicopathologic
correlation with history and exclusionary findings.
No pathologic findings are present that can explain death based
on inference, despite clinicopathologic correlation with history
and exclusionary findings.

38. CLASS I
Definitively fatal acute pathologic finding(s)
are identified that imply the cause of death,
based on clinicopathologic correlation with
the history and exclusionary findings
•Decapitation
•Multiple trauma (high energy)
•Intraoral shotgun wound
•Ruptured myocardial infarct
•Ruptured aortic dissection
Boarteraptors

39. CLASS II
Potentially fatal acute pathologic finding(s) are
identified that imply the cause of death, based on
clinicopathologic correlation with the history and
exclusionary findings
•Acute coronary thrombosis
•Acute myocardial infarct
•Acute lobar pneumonia
•Hanging
•Strangulation
•Acute drug/alcohol intoxication
filled
bleedweed
using
a
heartattack

40. CLASS III
Potentially fatal chronic pathologic finding(s)
are identified that imply the cause of death,
based on clinicopathologic correlation with
the history and exclusionary findings
•Atherosclerotic heart disease
•Hypertensive heart disease
•Hypertrophic cardiomyopathy (any
cardiomyopathy)
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hypotension
sellertoclaw

41. CLASS IV
Non-definitive or non-specific pathologic findings
are present that can explain death based on
inference from clinicopathologic correlation with
history and exclusionary findings
•Plastic bag suffocation
•SUDEP
•Airway obstruction (non-fixed)
•Positional/restraint asphyxia
•Hypothermia (exposure to cold)
•Hyperthermia (heat stroke)
•Anaphylaxis
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42. CLASS V
No pathologic findings are present that can
explain death based on inference, despite
clinicopathologic correlation with history and
exclusionary findings
•Negative autopsy with no history
•Fresh bodies with no context
•Decomposed/skeletonized bodies
plateby
case
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bag
lawnosofttinlogs
toandie

43. MECHANISM
OF DEATH
Definition
Physiological derangement due to the cause that
results in death.
Examples?
Haemorrhagic shock
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physifedwhimtht
areafor
COD
Scarke
andaametal
notacase

44. MANNER
OF
DEATH
Definition
Circumstances of death, i.e. how the COD
came about
5 Classifications
1.Natural
2.Accident
3.Suicide
4.Homicide
5.Undetermined
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coroners
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45. CASES BY
MANNER

46. CLASSICAL
AUTOPSY
PATHOLOGY

47. 1111
old
chorial

48. epien
Class
J

49. ringite
ClassE

50. lotsof
blood
ClassF
subdad
levorbed
bearglt
slle
a
sunken
ppl
can
live
wth
this
potatillythe

51. candid
corted
of
brutes
earI
thinkleft
centale

52. iii
in

53. subodh
was
class
F

54. bad
isolate
ChaseI

55. fatty
liver
ClassIv
of

56. insideof
gullah
starch
spot
of
ISI
wafer
notpet
dunk

57. storlays
YES
and
all

58. non
spells
pucker
weak
dolist
ClosFU
U

59. GSW
clef

60. State
netfor
distener

61. multis
lesions
at
lowgall
bladder
by
tune
ClassI
sttmtt.­at
abduris
adof
blal
ClanI

62. POSTMORTEM CHANGES

63. Post-mortem changes
ImmediateEarly Late
Sofluid1
way
at2
after
rigo
motis
flail
Class
ofmktg
coital
Alsogetsfaced
postrigor
mortis

64. Immediate
Loss of voluntary
power
No respiration or
circulation
Early changes
Cooling of body
Drying of eyes (tachenoir)
Muscle changes
{Primary flaccidity
{Rigor mortis
Pooling of blood in
dependent areas
(hypostasis)
Late changes
Autolysis
Decomposition

65. The “Mortises”
{Rigor
{Livor
{Algor
Decomposition
{Putrefaction
{Mummification
{Adipocere
stffsenattdthlatedzes­lsubpanifiat.in

66. ALGOR MORTIS
•The COOLINGof the body after death
•Rate VARIABLE, dependent upon:
•Ambient environmental temperature
•Temperature of the body before death
•Clothing and coverings
•Body Surface area to mass ratio
beeIghBMI
more
insulation
coolsslow
anadult
coolsshowtheninferty
In't
meanby
tap

67. RIGOR
MORTIS
•Initial flaccidity
•Development of rigor
•Passes off
•TEMPERATURE DEPENDENT
•Cooler = slower onset
•Small muscles to big muscles
sht
hsallel
rusts
mfg
of
a
brb

68. RIGOR MORTIS
•ATP can no longer be made aerobically
•ATP required to sever actin-myosin cross bridges
for muscle relaxation
•Body can make ATP via anaerobic glycolysis for a
bit
•When body glycogen is depleted, ATP diminishes
•Can no longer break A-M bridges and go into
rigor
•Muscle tissue must be broken down by enzymes
(bacterial) during decomposition which degrades
myosin heads
lackof
cellular
integrity
otolysisausfar
north
gasany
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rolesdntbeATP
IsA
stat

69. LIVOR
MORTIS
•Also known as LIVIDITY or POSTMORTEM
HYPOSTASIS
•POOLINGof blood after death
•POSITION / GRAVITY-DEPENDENT
•Face up (supine)
•Face down (prone)
•FIXED LIVIDITY
•Indicates longer postmortem interval
•Blood no longer shifts
yes
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stay
inas
athtly
sub
the
settlingof
bloodin
splet
am
of
body
canbe
undid
Cindyis
rodandstaff
deck
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stysstillbyeyl
that
bloodstys
feelin
tissues
Josef
tells
ye
a
pour
was
in
apasithforalaythe

70. ARTIFACTS OF
LIVIDITY
•Hypostatic hemorrhages coalesce
to form bruise-like marks on the
body known as Tardieu spots
•Unlike bruises, Tardieu spotsare
confined to areas of intense
lividity
apasithfor
a
Tudor
gets
still
blackspotssoldby
highlividly
blad
isoutinth
t.su

71. ARTIFACTS
OF
LIVIDITY
Tardieu spots
•Hemorrhages in skin and organs due to lividity
•Hypostatic artifacts maybe misinterpreted as injury
•When seen in the neck may be misinterpreted as
strangulation
•Similarly if seen on conjunctivae, worrisome for
neck compression
•For this reason, we insist that the body is
transported face up (on their back)
badpath
rems
thiswild
radar
this

72. •Type and rate of decomposition is
temperature and humidity
dependent
•Hot and humid
•PUTREFACTION
•Bacteria driven
•Hot and dry
•MUMMIFICATION
•Dehydration driven
•Damp and free of oxygen
•Saponification
(ADIPOCERE Formation)
•Fat breakdown
•SKELETONIZATION is final
common result
restadmintape

73. DECOMPOSITION-PUTRIFACTION
•Skin DISCOLOURATION
•Deep red, green, black
•MARBLING
•Venous pattern on skin
•BLOATING
•Gas formation
•SKIN SLIPPAGE
•Epidermal blistering and peeling
•Hair and nails detach
2stsepofdeep
autobiyleak
by
day
baton
freetogo
when
that
so
stetscomlyinlowquiltof
abdomen
beanspointftp.inthd
Get
minutes
demoslethargy

74. DECOMPOSITION
-PUTREFACTION
?Hot and Humid
?Putrefaction is a chemical process (bacterial
action)
?Gas = BLOATING
?Fluid = “PURGE”*
?Fluid leaks from orifices and accumulates at
scene
?Purge fluid is NOT BLOOD!
?Marbling
?* Internal pressures build up due to gas
formation (bloating), forcing red-brown
decomposition fluids from the bowels and lungs
through the mouth and nose ('purge fluid').
A
811
Effigy
of
LotcandoSelloff

75. DECOMPOSITION -
MUMMIFICATION
•Postmortem DRYING of body
•Skin is “leathery”
•Tissues are DEHYDRATED
•Organs become DESSICATED
•Time course is VARIABLE
erythy
shrinks
girls
will
presentcopalto
putrefation
can
relydorkfigots
salinedipto
obtain
fingerprints

76. DECOMPOSITION
-ADIPOCERE
•DAMP
•Waxy substance consisting chiefly
of fatty acids and calcium soaps
that is formed during
decomposition of dead body fat in
moist or wet anaerobic conditions
4the
worstsalty
Setsbackdooratpalena
soy
ruts
not
comedyfedindrug
deaths

77. POSTMORTEM TAPHONOMY
?Environmental influences on body
AFTERdeath
?Most common:
?Insects(MAGGOTS)
?Carnivores (postmortem PREDATION)
?Humans (clandestine activity,
DISMEMBERMENT)
9kinin
patination

78. POSTMORTEM
TAPHONOMY
mygts
Ian
lently
be
maggots

79. POSTMORTEM
TAPHONOMY
eat
crabs

80. •QUESTIONS?