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Forensic Medicine > Post-Mortem Changes > Flashcards

Post-Mortem Changes Flashcards

1
Q

List the stages of death

A 
Somatic or clinical death occurs and then cellular death begins 
Cooling 
Hypostatic lividity 
Rigor mortis 
Putrefaction 
Skeletonisation
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2
Q

Why does the body cool after death

A

Body stops creating energy after death and instead starts losing it

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3
Q

What causes hypostatic lividity

A

Blood settling in the capillaries after death - stops circulating
It settles with gravity

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4
Q

What is putrefaction

A

The breakdown of the body and its tissues/cells

Caused by body’s own bacteria and enzymes

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5
Q

How long does it take putrefaction to set in

A

Occurs over the days/weeks/months following death

Dependent on the environment

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6
Q

How long does skeletonisation take to occur

A

Most likely years after death

Could be months if conditions are right

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7
Q

What is algor mortis

A

The chill of death

The body cooling after death

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8
Q

What is livor mortis

A

The darkening of death

Skin changes colour (purple/red) due to blood settling

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9
Q

What is rigor mortis

A

The stiffening of death
Muscles seize up after death and body becomes stiff
Occurs over hours

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10
Q

What are the benefits of post-mortem changes

A

Can be used to confirm death - indisputable and confirms resus is futile

Allow you to estimate the time of death - post-mortem interval

Have specific forensics uses - suggest position at death or movement of body

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11
Q

What are the problems that post-mortem changes can cause

A

Produce confusing artefacts

Destroy evidence of identity, injury & mask disease (especially in advanced cases)

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12
Q

Which part of the body is the most resistant to hypoxic injury

A

Bone and corneas - survive up to 48hrs
Skin - survives up to 24hrs
Can be harvested and transplanted for days after due to resilience

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13
Q

Which part of the body is the most sensitive to hypoxic injury

A

The CNS - brain and spinal cord
Only last about 4 minutes without O2

Peripheral nerves last 5 mins

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14
Q

How long can skeletal muscles survive hypoxia

A

Around 3 hours

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15
Q

How long can blood cells survive hypoxia

A

Around 6 hours

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16
Q

List potential causes of PM artefacts

A 
Collapse/Falls at the time of death
Resuscitation efforts - can cause damage
Animals - if body unprotected
Water
Fire
Recovery of body - e.g. use of ropes can cause damage
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17
Q

How can collapse or falls at the time of death lead to PM artefacts

A

Strike nearby objects or the ground when falling
Don’t have the protective reflexes to protect themselves
Typical sites include the eyebrows, nose, chin, cheek (protruding areas take brunt)
Also affects the back of head if fall backwards
These injuries can have nothing to do with the CoD (facial injury from forward collapse following cardiac arrest)

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18
Q

List potential PM artefacts caused by resuscitation efforts

A

Bruising to neck, face, chest
Scratch abrasions to face
Abrasions on inside of cheek - rubbed against teeth due to intubation or mask
Mask marks
Needle puncture marks - cannulas
Gripping of arms to move or lift patient can cause bruising
(particularly upper arms)
Localised defibrillator burns - especially if skin is dry
Chest compression can perforate the stomach - lots of force applied to body

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19
Q

What increases the risk of stomach perforation during CPR

A

If done on a full stomach

Or if carried out improperly

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20
Q

Which animals typically leave PM artefacts

A

Insects - small lesions/bites
Fish / crabs - body from water, eat exposed areas first
Rats - eat at exposed areas (can jump high!)
Pets - if owner dies in house and isn’t feeding them or discovered for some time

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21
Q

List common artefacts of immersion

A 
Entry impact - if jumping in from height
Washerwoman change
Gooseflesh 
Rocks & river bed injuries 
Rocks & sea bed injuries in tidal water
“Undressing” by water movement
Fish & crabs
Recovery of body
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22
Q

List common artefacts of fire

A

PM burns & tissue loss
Skin splits - can occur when body is moved or before (due to heat)
Heat fractures
Extradural haematoma
Falling masonry
Recovery of body - will be fragile due to heat damage

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23
Q

What is maceration

A

A form of putrefaction that occurs in fetuses’ when in utero
The womb should be sterile no putrefactive bacteria to break down the foetus so it autolyses instead
Form of wet putrefaction

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24
Q

Which type of putrefaction is favoured by wet conditions

A

Adipocere

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25
Q

Which type of putrefaction is favoured by dry conditions

A

Mummification

Also favors warmth

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26
Q

What type of putrefaction is favoured by bacteria

A

Wet putrefaction

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27
Q

What are the possible sources of information for determining ToD

A 
Corporal evidence (on the body)
Environmental & associated evidence
Anamnestic evidence (habits & activities) - often the most useful
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28
Q

What is anamnestic evidence

A

Evidence based off the victims usual habits and activities

E.g. when/where they last seen alive, where should they have been according to schedule

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29
Q

How can post-mortem interval be used by the police

A

Can give someone an alibi or show they had opportunity

e.g. compare window of death to where they were at the time

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30
Q

Describe the rate method for calculating PMI

A

Observe or measure changes which occur at known rate - estimate death from this
Changes initiated or stopped by specific events i.e. death
(e.g. lividity, rigor, cooling, putrefaction as all start at time of death)

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31
Q

There is no reliable method for calculating PMI - true or false

A

True

All have degrees of variation

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32
Q

Describe the concurrence method of determining PMI

A

Uses events which occurred at known times
e.g. watch stopping in fire or stage of digestion of last known meal (if food is still identifiable in stomach they died shortly after last meal)

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33
Q

What are the main issues with the rate method for determining PMI

A

Many physico-chemical changes begin at death and each has its own time factor (e.g. lividity, rigor, cooling, vitreous K, putrefaction)
Unpredictable endogenous & environmental factors can effect results

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34
Q

The longer the PMI the less precise the estimate - true or false

A

True
Can be accurate if within a few hours of death but beyond this the timings are vague (i.e. putrefaction can only be accurate to days/weeks)

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35
Q

Which factors are used in practice to estimate PMI via the rate method

A

Rigor, cooling and putrefaction

Factors are combined

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36
Q

How do you measure core temperature in the deceased

A

Subcostal stab - temperature probe put into the liver
Rectal temperature

Serial measurements are preferred

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37
Q

In what cases would you not use a rectal temperature

A

Suspected sexual assault cases
Rectum should be undisturbed in sexual cases so that it can instead be swabbed for DNA, semen etc.
More important than temp
Inserting a thermometer can contaminate the area

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38
Q

Why is an internal temperature required to estimate PMI

A

The outside of the body (e.g. Axilla or mouth) will be cooler than core temperature
Internal is more accurate of true core temperature

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39
Q

What environmental factors are required for a body to cool after death

A

Cooling requires a difference between body and environmental temp
Only useful in temperate and cool climates
In hot places putrefaction sets in quicker - may not have fully cooled

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40
Q

In what time frame is body temperature useful in indicating PMI

A

Useful in the first 24hrs and only in temperate/cool climate
Only truly reliable during the linear cooling phase which is typically 6-12 hours PM

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41
Q

Which factors influence the rate of body cooling

A 
Body size
Exposed surface area 
Environmental temperature and how it fluctuates 
Drafts & humidity
Clothing & coverings - retains heat 
Immersion in water - cools faster
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42
Q

Larger bodies cool faster - true or false

A

False
Smaller bodies cool faster as they have large surface area and low volume
Larger bodies can retain more heat - greater mass

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43
Q

A flow of air or a draft will speed up the cooling process - true or false

A

True

The heat is moved off the body

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44
Q

Describe the progression of body cooling (as in Newton’s Law of cooling)

A

At first the body retains some heat so temperature plateaus (up to 5 hours from death)
The heat is lost quickly by convection, radiation, conduction and evaporation
Cooling occurs in a linear fashion for 6-12 hours
After this the curve levels out - becomes unreliable

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45
Q

Bodies can increase in temperature slightly due to putrefaction - true or false

A

True

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46
Q

List some of the unknown variables that affect the cooling process

A

Length of plateau can vary
Body temperature at time of death - usually unknown
Environmental temp during cooling period - particularly if there is fluctuation

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47
Q

Which conditions can decrease body temperature at time of death

A

Hypothermia
CCF
Haemorrhage

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48
Q

Which conditions can increase body temperature at time of death

A 
Heatstroke
Septicaemia
Pontine haemorrhage
Strangulation,
Struggle before death
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49
Q

What is the Henssge Nomogram used for

A

Used to estimate ToD from body temperature
Based on a mathematical cooling model
Allows us to account for certain variables - applied as corrective factors

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50
Q

What assumptions does the Henssge nomogram make

A

Normal body temperature at time of death

No change in cooling conditions during PMI

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51
Q

Which variables can the Henssge nomogram account for

A

Amount of clothing
Body weight
Drafts
Whether or not the body was in water

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52
Q

What is the main issue with the corrective factors in the Henssge nomogram

A

Corrective factors are subjective - e.g. thick vs thin layers
Depends on the pathologist’s experience

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53
Q

When can the Henssge nomogram NOT be used

A

Strong heat source nearby
Cooling source nearby
Underlying surface conducts heat
Will alter the cooling process and make estimation unreliable

Abnormal body temp. at death
Body has been moved - change un surface area will change cooling speed

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54
Q

Bodies cool slower in water than in air - true or false

A

False
They cool faster as water is a better heat conductor
(water removes heat from body by conduction)

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55
Q

What is the difference between still and flowing water in terms of body cooling

A

Bodies cool 2x faster in still water than still air
They cool 3x faster in flowing water than still air
So bodies cool faster in moving water than in still
Tidal is considered similar to still water

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56
Q

What is primary muscle flaccidity

A

The loss of muscle tone at death

Body goes floppy/limp and collapses

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57
Q

List the progression of muscle flaccidity after death

A

Start with primary flaccidity
Then muscles become rigid in rigor mortis (over hours)
Then it relaxes again into secondary flaccidity which is permenant

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58
Q

What is cadaveric spasm

A

Immediate rigor following death
Stiffening occurs at moment of death & persists into period of rigor mortis
A rare phenomenon

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59
Q

What can cause cadaveric spasm

A

Violent/emotional deaths
Victims will grab onto anything they can
Seen in drowning most commonly - grab onto weeds/plants

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60
Q

What causes rigor mortis

A

Death interrupts the actin-myosin pathway - there is no more energy for relaxation to occur (ATP required for this process)
This causes the muscles to stay ‘contracted’ and the body gradually stiffens

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61
Q

What can cause muscle stiffness in a corpse

A

Rigor mortis
Cadaveric spasm
Heat stiffening
Freezing the body

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62
Q

Describe the process of heat stiffening in a body

A

Seen in bodies in fire
The muscle is ‘cooked’ by the heat as the proteins within them coagulate
This causes the muscle fibres to shorten and the body flexes into pugilistic attitude

Don’t see proper rigor as a result

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63
Q

When does rigor mortis stop

A

Once the muscle itself starts to break down (actin-myosin links finally broken)
Or if the body is moved by another person - this ‘breaks’ rigor

64
Q

What happens when you ‘break’ full rigor

A

Occurs when you move a body in full rigor (e.g. undressing)

Rigor cannot reform so body will no longer be in ‘rigor’ position

65
Q

List some of the PM effects caused by rigor mortis setting in in involuntary smooth muscles

A

Involuntary ejaculation from glans penis due to rigor in the seminal vesicles
Gooseflesh due to rigor in the pilo-erector muscles of hair follicles
Pupils becoming unequal or irregular due to rigor in the iris

66
Q

Partially form rigor can reform once broken - true or false

A

TRUE
Once broken the rigor can continue to develop
Not seen in full rigor

67
Q

What factors can speed up the onset of rigor

A

Higher environmental temperature - rigor is an enzyme process so like warmth
Increased muscle activity prior to death - decreased energy store prevents relaxation
Starvation prior to death - depletes glycogen
Septicaemia
Also faster in children and the elderly

68
Q

What factors can slow the onset of rigor

A

Cold environmental temperatures

Lack of movement before death (slow, peaceful)

69
Q

Rapid onset of rigor is associated with short duration - true or false

A

True

Comes on quick = passes off sooner

70
Q

How long after death is rigor typically fully established

A 
Fully established by: 
3 h in 14% cases
6 h in 72%
9 h in 90%
12 h in 98%
71
Q

In what ‘sequence’ does rigor develop

A

It actually develops simultaneously in all muscles
However, smaller muscle groups becomes fixed sooner than in larger groups - these appear affected first

Eyelids and jaws & neck seen first
Then small joints of hands & feet > medium joints of elbows & knees > large joints of shoulders & hips

72
Q

Does rigor pass off in sequence

A

Yes it appears to - smaller muscle groups pass off first followed by larger ones
Putrefaction sets in and gets rid of rigor

73
Q

Is onset of rigor a reliable indicator of PMI

A

No

Onset and duration have a variable time course so not useful for individual cases

74
Q

How long is full rigor maintained (on average)

A

It remains for around 24-36 hours

75
Q

When does rigor typically first appear

A

First appearance on average 3 hours pm

76
Q

How long does it take rigor to pass off

A

Full rigor is maintained for around 24-36 hours then it starts to pass off
This takes another 24-36 hours

77
Q

What determines the intensity of rigor

A

The physique/muscle mass of the deceased

Rigor is very strong in adult males with large muscle mass and minor in the elderly with low muscle mass

78
Q

List the average PMI when rigor and cooling are combined (e.g. warm/flaccid vs warm/stiff)

A

Warm & Flaccid (rigor not set in yet)– dead < 3 hours
Warm & Stiff – dead 3-8 hours
Cold & Stiff – dead 8-36 hours
Cold & Flaccid (rigor passed)– dead >36 hours

79
Q

Lividity is a good indicator of PMI - true or false

A

False

It is however a good indicator of body position since death

80
Q

Describe the appearance of lividity

A

Seen as purple discolouration in dependent areas (lowest by gravity)
Horizontal fluid level with an irregular patchy margin
Areas of contact pallor
Punctate haemorrhage within intense lividity

81
Q

What causes contact pallor in lividity

A

The vessels in the areas in contact with a firm underlying surface (e.g. floor) are compressed by body weight
Blood cannot settle here as vessels are compressed so these areas remain pale
Clothing creases/folds can cause contact pallor too

82
Q

If the lividity doesn’t match the body position what does it suggest

A

That the body was moved after death

83
Q

List the general timings of lividity

A

Blood begins to settle at death
Red patches may appear within 30 min (up to 2 hrs)
Well formed by 4 hrs
Max intensity at 8 – 12 hrs (will blanch)
Fixed after 12 h (no longer blanches)

84
Q

What can delay or reduce lividity

A

Anaemia

Haemorrhage

85
Q

How can you tell if lividity is fixed or not

A

If it no longer blanches on fingertip pressure it is fixed

Not an absolute science

86
Q

What causes fixing of lividity

A

The blood thickening - no longer moves

87
Q

Can lividity move

A

Yes

If the body is moved before lividity is fixed the blood can redistribute

88
Q

Describe what happens to lividity if the body is moved less than 6 hours after death

A

The lividity will not be well formed
The primary pattern of lividity (original position) will not be fixed and will fade away
A new secondary pattern forms (matching the new position)

89
Q

Describe what happens to lividity if the body is moved more than 10 hours after death

A

The lividity is well formed but not fully fixed
The primary pattern of lividity is fixed enough to remain
However, there is still enough fluid blood to move and form a new secondary pattern
Gives a dual distribution of lividity (e.g. front and back if body flipped)

90
Q

Describe what happens to lividity if the body is moved more than 24 hours after death

A

The lividity is well formed and fixed
The primary pattern is fixed and so it remains
Not enough fluid blood to create a new secondary pattern

91
Q

What causes punctate hypostasis in lividity

A

The small blood vessels within the area of lividity become engorged/congested with blood and will burst and bleed slightly
Small ‘punctures’ of bleeding

92
Q

What causes bright pink lividity

A

Refrigeration or hypothermia

Bodies retain oxygen better so red colour stays better

93
Q

What causes cherry pink lividity

A

Carbon monoxide poisoning

94
Q

What causes scarlet lividity

A

Cyanide

95
Q

What causes chocolate brown lividity

A

Poisoning

Methaemoglobin (chlorate) creates the colour

96
Q

Internal lividity can mimic which disease processes

A

In the heart it can mimic MI
In lungs it mimics pneumonia
In intestines it mimics infarction

97
Q

List the different types of putrefaction

A 
Maceration (sterile autolysis of foetus)
Wet putrefaction (commensal flora)
Skeletonisation
Mummification (dry conditions)
Adipocere (wet conditions)
98
Q

What causes wet putrefaction

A

The commensal flora of the body breaks down the tissues (rot from inside out)
This is the most common type of putrefaction

99
Q

How does bacteria spread in putrefaction

A

Bacteria spread from gut and respiratory tract to other tissues via bloodstream
Starts in those tracts (lots of microbes, especially gut)) before spreading

100
Q

What determines the rate of putrefaction

A

Environmental temperature

101
Q

What is the optimal temperature for putrefaction

A

21 – 38 ‘C

102
Q

Which bacteria are responsible for putrefaction

A

Most already present in GI tract and URT
- Coliforms
- Clostridia
- Anaerobic bacilli
- Micrococci
Some exogenous bacteria can be introduced via wounds, insects, animals and contribute/ speed up process

103
Q

Which factors speed up putrefaction

A 
Slow initial cooling- e.g. presence of clothing or bedding
High environmental temp
Humidity
Obesity
Terminal septicaemia
Wounds
104
Q

Which factors slow down putrefaction

A 
Rapid initial cooling
Refrigeration
Fire (heat fixation)
Blood loss - prevents bacteria spreading through blood
Embalming - fixes the tissues 
Immersion
Burial
105
Q

List the sequence of events seen in putrefaction

A 
Green discolouration in abdomen RIF - after 2 d
Passage of rigor 
Marbling after a few days 
Skin blisters & slippage 
Gas production & bloating after weeks
Loss of hair & nails
Liquefaction after months
Skeletonisation after years
106
Q

How does embalming slow putrefaction

A

The fluid fixes the tissue via the bloodstream

Prevents them breaking down

107
Q

How does burial slow putrefaction

A

Burial takes body away from O2 and some bacteria

108
Q

What causes marbling in a putrefying body

A

Bacteria alter the blood as they break it down and creates pigments which can be seen through the skin
This causes the marble pattern as the vessels get marked out on the skin
Occurs after a few days

109
Q

Which gases are produced during putrefaction

A

Methane, H2, H2S, NH3 (ammonia)

Ptomaines (putrescine, cadaverine)

110
Q

How do sniffer dogs find corpses

A

They smell the amine gases produced by the putrefying body

Highly sensitive to them

111
Q

When does skin slippage occur

A

Less than a week after death

The epidermis blisters as it fills with putrefactive fluid

112
Q

Describe the process of skin slippage in a dead body

A

The epidermis fills with putrefactive fluids and forms blisters (layers of skin separate)
They have a thin cover which bursts and slips easily
Top layer of skin slips off
Underlying layer will dry out

113
Q

When does gaseous bloating occur in a dead body

A

A week or more after death

114
Q

Putrefied bodies will deflate slightly on autopsy - true or false

A

True

The gases produced by putrefaction will be release when the tissues are cut into

115
Q

Which parts of the body are typically inflates by putrefactive gases

A

Gas inflates the lips, cheeks eyes, chest, abdomen and scrotum

116
Q

How is the stomach affected by putrefaction

A

It becomes discolored due to acid damage
The discolouration may form a fluid level (up to where contents were sitting on
Undergoes autolysis - acid starts breaking it down which speeds up putrefaction

117
Q

How is the heart affected by putrefaction

A

It becomes dilated and flabby

118
Q

How is the liver affected by putrefaction

A

Gases cause it to become soft and honeycombed

119
Q

How is the brain affected by putrefaction

A

Gases cause it to become soft and honeycombed

Liquifies

120
Q

How is the liver affected by putrefaction

A

It becomes soft and mushy

121
Q

Internal putrefaction causes haemolytic staining of which tissues

A

Blood vessels and airways

122
Q

Which organs/tissues are slow to putrefy

A

Uterus and prostate
This is because they are fibrous organs
Useful for identifying sex in decomposed bodies

123
Q

What happens in advanced putrefaction

A

Loss of solid tissue

Organs become grey and mushy

124
Q

How can stomach contents be useful in determining PMI

A

If time of last meal is known it can be useful
Food remains in stomach up to 3-4 hrs
So if undigested food present you can estimate that they were killed up to 3-4 hours after that meal

125
Q

What are the problems with using stomach contents to estimate PMI

A

Rates of emptying and digestion variable between people
Food may persist undigested for several days following severe trauma (ITU) - digestion shuts down to divert resources to more vital organs

126
Q

Describe the appearance of a mummified body

A

Skin becomes shrunken, dried and leathery
May be seen in toes, fingers lips etc if not whole body
Internal organs can be preserved or decompose

127
Q

Which types of putrefaction can actually preserve wounds

A

Adipocere and mummified skin can preserve wounds

Useful for forensic analysis

128
Q

What causes adipocere

A

A body being immersed in water - drowning or wet grave
Fatty tissue becomes fixed into adipocere - hydrolysis process
Seen in face, buttocks and chest- fatty areas

129
Q

What is the role of the forensic etymologist

A

They can estimate how long the victim has been dead based on number/species/stage of insects on body

130
Q

Which flies are typically found around bodies

A 
Calliphora vicina (bluebottle) seen indoors 
Lucilia caesar (greenbottle) seen outdoors

They are attracted by the smell

131
Q

Describe the lifecycle of a fly

A

Mature flies lay eggs on body
After 24 hours they hatch and become larvae (3 stages of growth)
After 4 days they go into their prepupa and a following 5 days later they become pupa
After 11 days they hatch as adult flies
These live for 4-5 days, mate and start the cycle again

132
Q

Where do flies lay their eggs on a body

A

They lay eggs in moist areas such as the eyes, up nose, mouth, perineum, wounds

133
Q

Describe how flies affect the body at different stages

A

Eggs are laid in moist areas
Young larvae feed on tissue - can create holes in body
Older larvae leave body or hide under it to pupate & hatch
May be several generations on body - may stick around the source
Succession of beetles and other insects come in to feed on larvae & tissues

134
Q

Which bacteria is important in the formation of adipocere

A

Clostridium welchii

The released fatty acids inhibit other bacteria

135
Q

Describe the appearance of adipocere

A

Fat on body converted into a waxy, pale, soapy substance

Has a sweetish, rancid odour

136
Q

How long does it take adipocere to develop

A

Weeks or months

137
Q

How long does mummification take

A

Weeks

138
Q

In which age group is mummification more common

A

More common in infants than adults

139
Q

Why might mould grow on a mummified body

A

Fungus can grow into mouth, airways, eyes and nose - moist areas
May appear as white regions on skin/in orifices

140
Q

What is cellular death

A

The breakdown of cells and tissues after the body has stopped living
A process not singular event - occurs at variable rates

141
Q

What is clinical death

A

This is when circulation/breathing stops and consciousness is irreversible lost
This can be recorded as a single event - e.g. time of death

142
Q

Different tissues and cell types will die at varying rates - true or false

A

True

Depends how resistant they are to hypoxia

143
Q

What internal injuries can be caused by chest compressions

A

Rib fractures - common
Stomach perforation
Cardiac laceration

144
Q

What additional time period must be accounted for when calculating time of death

A

The survival period
People may not die immediately from injury etc. and may survive for hours/days
Therefore ageing the injury may not actually give you an accurate time of death

145
Q

Which post-mortem changes can be assessed using the rate method for PM Interval

A

Lividity
Rigor
Cooling
These are used in practice

Vitreous K+ levels Putrefaction

146
Q

A dead body will never quite cool to exact environmental temperature - true or false

A

True
Unless it is very very cold and body is there for a long time
Metabolism of bacteria keep the temperature up slightly

147
Q

Which body factors can cause it to cool faster

A

Thinner body
Naked body

Will have a shorter plateau

148
Q

Which body factors can cause it to cool slower

A

Body with more fat
Heavy clothing

Will have a longer plateau

149
Q

Rigor can be delayed if the body was frozen - true or false

A

True
If body is frozen soon after death rigor can be postponed
Rigor can then set in on thawing

150
Q

Rigor mortis only affects voluntary skeletal muscle - true or false

A

False

It affects all muscle types: voluntary skeletal, cardiac and involuntary smooth muscle

151
Q

Does rigor mortis cause the muscles to shorten

A

No

There is no significant shortening, they just become stiff in the position the person died in

152
Q

Rigor can indicate the position someone was in at time of death - true or false

A

True - some of the time
Body will stiffen in position it died in
Can be affected by movement

153
Q

How long does it take for rigor to become fully established

A

Average is around 8 hours

However range is huge (2-20 hours)

154
Q

Why does discoloration in putrefaction first appear in the RIF

A

Putrefaction usually starts in the gut due to abundant bacteria
Caecum is the closest part of GI to the skin surface and is found in RIF
Green discoloration may in fact map out the intestines

155
Q

How long does it take a body to lose its hair and nails

A

Usually weeks

156
Q

How long does tissue liquefaction take

A

Usually months

Forensic Medicine (13 decks)

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