AUTOPSY TECHNIQUE AND THANATOLOGY😊

AUTOPSY TECHNIQUE AND THANATOLOGY

• Autopsy: AKA postmortem examination/ necropsy

Types of Autopsy

Virtual autopsy (Virtopsy):

• Complete imaging of body (CT/MRI).

• Advantage: 
• Non/minimally invasive
• structural lesions can be identified.

• Disadvantage: 
• Functional lesions can’t be identified.

Psychological autopsy:

• Indication: To confirm suicidal death.

• Objective: To assess mental state of deceased.

• Procedure: Interview family, friends & relatives.

SEQUENCE OF DISSECTION

Incisions

• I shaped incision (M/c):
• Starts at: Chin.
• Ends at: Pubic symphysis.

• Y shaped incision:
• Starts at b/l acromion process meets at xiphoid process & ends at pubic symphysis.
• Females
• Extends below the breasts.

• Modified Y incision:
• Starts at b/l mastoid process, meets at xiphoid & ends at pubic symphysis.
• Asphyxial death

• Inverted Y incision:
• Done in newborns.
• Starts from the chin upto umbilicus, bifurcates to b/l mid inguinal point.

• X incision:
• In custodial deaths.
• Incision applied on the back of the body.
• Assesses deeper injuries.

Techniques of Organ Removal

• Virchow:
• Mnemonic: Vone by Vone
• Organ by organ.
• M/c,

• Letulle’s:
• Mnemonic: Letulle → (Let All) Out together
• En masse
• Rapid removal.
• Inter-organ relationship can be studied.

• Ghons:
• Mnemonic: Ghons focus → or Block
• Block (Eg: Cervicothoracic/abdominal/urogenital block).

• Rokitansky:
• Mnemonic: Rockitansky → Inside the Tunksky → Insitu
• In situ: In infectious diseases (HIV, Hep B, Covid).

Note: 

• Disappearance of evidence Punishable under 238 BNS.
1. in a poisoning case embalming before autopsy can flush out poisons
2. gastric lavage sample discarded

• Mnemonic: disappeared within 24 hrs (23.8)

Individual Organ Dissection:

• Heart dissection: 
• Inflow - outflow method.
• Along the direction of blood flow.
• Right atrium → Right ventricle → Left atrium → Left ventricle.

• Stomach dissection:



• Double ligation:
• Cardiac end: 
• Pyloric end.
• Preserve contents of stomach for further examination.
• Incision: Along greater curvature.
• Magenstrasse:
• In corrosive poisoning
• Area of max. damage → Lesser curvature

NOTE:

• In starvation all organs shrink, so does the liver, lungs etc
• Except gallbladder

• Elevation of P selectin
• Distinguish antemortam from Postmortem death

Exhumation (Disinternment)

• Lawfully digging the body out of earth.

• Authorized by: Magistrate.

• Time limit: No maximum limit in India.

• Preservation of soil:
• To differentiate from post mortem imbibition from arsenic poisoning
• Imbibition: Absorption of metallic poison from soil into body post death

• Poison that can be identified from exhumed body
• Arsenic (M/c)
• Endrin

• Mnemonic: Digging after death → Arts (Arsenic) till end (endrin)

Post Mortem Changes

• Thanatology: Study of death.

• Taphonomy: Study of post mortem resorption of body.

Immediate changes (Somatic death)

• Loss of voluntary movement.

• Irreversible stoppage of circulation & respiration.

Early changes

• Eye changes

• Algor mortis (Cooling).

• Livor mortis (Staining).

• Rigor mortis.

• Mnemonic: All mortis are early

Late changes (Decomposition)

• Autolysis: Lysosomal enzymes.

• Putrefaction: Bacterial enzymes.
• Source of bacteria: GIT, trauma site.
• Route of spread: Blood vessels.
• Chief agent: Clostridium welchii
• Lecithinase enzyme

Eye changes

Retina

• Kevorkian sign/railroad sign/cattle trucking sign 
• Fragmentation of blood vessels
• Present soon after death
• because circulation stops immediately

Best indicator for Time since death

• K+ in vitreous

Sclera

• Triangle shaped opacities on either side of cornea → Tache noire sclerotica

• When died with open eyelids → dust deposition / drying → 3 - 6 hrs → triangular opacities

• Corneal opacificaiton → 6hrs
• D/d: Cobra bite

ALGOR MORTIS/ POSTMORTEM COOLING

Post mortem caloricity:

• Body remaining warm after death
• D/t high Body Core Temperature during death

• Causes:
• NOT BURNS
• Heat stroke,
• Pontine hemorrhage
• Loss of thermoregulation
• Septicemia,
• Fever
• Tetanus/strychnine poisoning.
• Continuous muscle contraction

• Note: Postmortem caloricity is not seen in burns.

LIVOR MORTIS

• Cadaveric or Postmortem lividity/ PM staining/ PM hypostasis/ suggilation/ cogitation/ Vibices/ darkening of death
• Mnemonic: Saji (suggilation) coloring Liver → Incognitio (cogitation)

• Bluish discolouration on dependent areas d/t hypostasis of blood.

• Distribution based on position:
• Supine position: Back of head, chest, abdomen, legs.
• Prone position: Front of head, chest, abdomen, legs.
• Vertical position: Glove & stocking pattern.

• No Hypostasis in
1. Body in Fast flowing river or
2. hypovolemic shock
3. severe anemia

• But In Floating River



• In front of face
• front of neck
• glove and stockings

Change with time:

• Onset: 30 min.

• Max: 6-12 hrs.

• Merges with putrefaction colour.

Livor mortis vs. Bruise

Fixation:

• Happens at 6-12 hrs (8 hrs).

• Pressing on fixed hypostasis will not blanch.

• Movement of body
• Before fixation
• Hypostasis also moves.
• Secondary lividity.
• After fixation :
• No change in hypostasis.

• Contact pallor:
• Areas in tight contact with a surface Pallor, no staining.

Color:

RIGOR MORTIS

Rigor Mortis in Fetus

• Absent in fetus < 7 months
• (Also Adipocere)

• Due to underdeveloped actin and myosin filaments.

Seasonal variation:

• Summer: 18–36 hours.

• Winter: 24–48 hours.

Rigor Mortis in Wasting Diseases

• Thin muscle mass, decreased ATP storage.

• Seen in: cholera, TB, cancer, cachexia, typhoid.

• Early onset, short duration.

Rigor Mortis in Violent Death

• Examples: cutthroat injury, firearm injury.

• Early onset, short duration.

Rigor Mortis in Thick Muscle

• Increased ATP storage.

• Late onset.

Exceptions

• Strychnine poisoning: Early onset, long duration.

• Arsenic poisoning: Late onset, long duration.

• First seen: Involuntary > Voluntary muscles.

• First site: Myocardium.

• Externally : Eyelid

Nysten’s rule:

 

• Eye lid > neck > jaw > face > thorax > upper limb > abdomen > lower limb > fingers & toes.

• Cause of Rigor mortis
• ATP depletion

Rule of 12:

Cadaveric spasm/instantaneous rigor/cataleptic rigidity:

• In some voluntary muscles → No primary relaxation

• Drowning, electrocuting, suicidal gunshot, fear/excitement

• Only Seen in antemortem

• Not seen in brain injury

Conditions mimicking rigor mortis:

• Heat stiffening: Burn.

• Cold stiffening.

• Gas stiffening: Decomposition.

• Cadaveric spasm.

LATE CHANGES (DECOMPOSITION)

Putrefaction:

• Takes 5-10 days.

• Steps
1. Color change.
2. Gas production.
3. Liquefaction of tissues.

• Delayed in
• Strychnine, metallic poison, Carbolic acid

1. Color:

• 1st site:
• Aorta.

• 1st external site:
• Right iliac fossa (Greenish patch) 
• Time since death:
• Summer: 12-18 hr,
• Winter: 1-2 days.

• Marbling:



• It results due to bacterial activity
• D/t sulfhemoglobin deposition of vessel walls.
• Greenish > Reddish blue color.
• Time since death: 36-72 hr.
• Takes 1 1/2 to 3 days to make Marble

2. Gas:

• Hydrogen sulphide

• Findings
• Gas stiffening:
• Completely bloated.
• Post mortem purge:
• Bleeding from nostrils & mouth.
• Blisters.

• Note: PM vs AM blisters:



Feature	Postmortem (Putrefaction)	Antemortem (Burns)
Content	Gas	Inflammatory fluid
Base	Pale	Reddish

3. Liquefaction:

• Mnemonic: Totally () Liquid () ayalum → Sin (Stomach, Intestine) → Specially () Live in () Brain () and Heart ()

• Earliest:
• Larynx, Trachea.

• Early (in sequence):
• Stomach, Intestine, Spleen, Liver, Brain, Heart (Last).

• Late:
• Prostate: Male
• Uterus: Female (Non-gravid)
• Skin.

• Last:
• Bone, Tooth

Casper’s Dictum:

• Rate of putrefaction: Air (Fastest) > water > Earth (Slowest).

• 1 (Air) 2 (Water) 8 (Earth).

• Awesome

Time Sequence of Significant Changes After Death

Entomology:

• Egg - Maggie - Pepsi - Flyte
• Egg: 12 hours
• Maggots: 24 hours
• Pupa: 4-7
• Fly: 1 week - 2 week

 

• Study of insects.

• Time since death.

• Identify poison (From insects).

• Place of disposal (Based on species of insect).

Modified Forms of Putrefaction

1. Adipocere/ grave wax/ saponification

2. Mummification

Viscera Preservation for Chemical Analysis

• For poison detection.

• Routinely sent samples:
• Blood (most reliable): Circulation (Peripheral Femoral vein).
• Stomach & contents: Storage.
• Small intestine (Upper 30cm): Absorption.
• Liver (500gm): Metabolism.
• Kidney (Half of each): Excretion.

Samples sent for specific poisons:

• Preservative:
• Saturated sodium chloride solution (m/c).
• Avoided in:
• Aconite poisoning,
• Corrosives except carbolic (phenolic acid) acid.
• Rectified spirit (90% alcohol) (Ideal).
• Avoided in:
• Formalin poisoning,
• Phosphorus poisoning,
• Alcohol poisoning.
• Mnemonic: Dont FAP after drinking Spirit
• No preservative:
• Bone, hair, nail, teeth, lung.
• Formalin as preservative:
• Never used (Extraction of poison very difficult).

• Mnemonic:
• Glycerol → karayam upayogikkam → Preserve Virus → Viral infection vannapo cry
• Sodium ulla Fluids (blood, urine, csf) → Fluoride (sodium)
• Blood has sodium and potassium
• Urineil () kude thyru (thymol) vannu

Samples sent for DNA analysis:

• Liver > Cardiac muscle > Molar teeth > Other teeth, hair with roots, blood

• Fresh dead body: Blood EDTA preservative.

• Early decomposition: Spleen/muscle.

• Advanced decomposition : Bone/hair/teeth.

• Nail cannot be used for DNA deduction