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CHAPTER 5: ASPHYXIAL DEATHS

Complete WBUHS Exam-Oriented Answers

(Based on Reddy's Essentials of FMT 36th Ed., P.C. Dikshit FMT, and Parikh's FMT)

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LONG & SHORT ANSWER QUESTIONS (15 & 10 Marks)

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Q.1 - Types of strangulation; External & Internal autopsy findings of throttling; What is Lynching? [2.5+6+1.5=10] - Bankura Sammilani MC

A. Types of Strangulation [2.5 marks]

1. Ligature Strangulation - constriction of neck by a ligature tightened by an external force (not body weight)
2. Manual Strangulation (Throttling) - compression of neck by hand/hands
3. Mugging - compression by forearm across front of neck (arm-lock method)
4. Garroting - a cord looped around neck from behind and tightened by a stick
5. Bansdola - a bamboo stick placed across neck and pressed against ground (seen in India)
6. Palmer strangulation - palm pressed over nose and mouth
7. Foot strangulation - rare form using foot on the neck

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B. External & Internal Autopsy Findings of Throttling (Manual Strangulation) [6 marks]

1. Face: Deeply cyanosed, congested, markedly puffy/edematous. Facial petechiae and subconjunctival hemorrhages are prominent (due to venous obstruction with continued arterial flow).
2. Eyes: Conjunctival hemorrhages, petechiae in the palpebral conjunctiva.
3. Mouth/Tongue: Tongue may protrude between the teeth, bitten by teeth. Frothy blood-stained discharge may be present.
4. Neck externally:
   • Finger nail marks (crescentic abrasions): Semi-circular or crescent-shaped abrasions from fingernails on the skin of the neck. These are pathognomonic of throttling. Multiple individual marks from each finger arranged in a row.
   • Fingertip bruises (pressure marks): Oval or circular bruises from the pulp of the fingers. Usually multiple, scattered over both sides of neck.
   • The marks may be from the victim's own hands (defensive) or the assailant's hands.
5. Petechiae over the face and neck - more prominent than in hanging.
6. Ligature mark: Absent (unless ligature strangulation is combined).

1. Neck muscles: Bruising and hemorrhage in the strap muscles (sternohyoid, sternothyroid), especially beneath the fingertip bruises. This is a key feature.
2. Hyoid bone: Fracture is common (more common in throttling than hanging - noted by Calcutta National Medical College). The greater horns of hyoid are most often fractured.
3. Thyroid cartilage: Fracture of thyroid cartilage (both superior horns/cornua) is frequent.
4. Cricoid cartilage: May be fractured.
5. Carotid arteries: Intimal tears of the carotid arteries (longitudinal splitting of intima) may be seen - an important internal sign of throttling.
6. Carotid sinus: Hemorrhages around the carotid sinus region.
7. Larynx/trachea: Mucosal congestion and hemorrhage.
8. Lungs: Markedly congested and edematous. Palpable Tardieu's spots (petechial hemorrhages) on the subpleural surface - more prominent than in hanging.
9. Brain: Congested, edematous, petechial hemorrhages in white matter.
10. Heart: Right side dilated and engorged with dark fluid blood.
11. Viscera: General congestion of all organs.

Important Note (WBUHS Frequent Point): The difference between hanging and throttling regarding hyoid bone - hyoid fracture is MORE COMMON in manual strangulation (throttling) than in hanging because in throttling direct pressure is applied at the level of the hyoid.

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C. What is Lynching? [1.5 marks]

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Q.2 - Dead body of 22yr female found floating in river; Inquest; Signs of antemortem drowning; Types of drowning; Fresh-water vs Sea-water drowning [1+5+4+5=15] - Deben Mahata Govt. MC

a) Who will hold Inquest? [1 mark]

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b) Findings indicating Antemortem Drowning [5 marks]

1. Fine white leathery froth at the mouth and nostrils (persistent, tenacious, mushroom-shaped froth) - forms due to mixing of water, air and mucus during the act of drowning.
2. Cutis anserina (goose skin) - cutaneous vasoconstriction from cold water, a sign of vital reaction.
3. Washerwoman's hands - bleaching, wrinkling, maceration of the palms and soles.
4. Weeds, sand, mud or other foreign material tightly clutched in the hands (cadaveric spasm - the "death grip") - this is the surest sign of antemortem drowning.
5. Abrasions and bruises from struggling in water or impact with rocks.

1. Emphysema aquosum - overdistension of lungs (ballooned), filling the thoracic cavity, overlapping the heart. Rib impressions on the lateral surfaces of the lungs. This is the most important internal sign.
2. Paltauf's hemorrhages - pale pink/bluish-red subpleural hemorrhages (interstitial) in the lung parenchyma from rupture of alveolar walls.
3. Water in stomach - drowning fluid swallowed during struggling; stomach may contain water, sand, weeds, mud.
4. Water in middle ear - water enters via Eustachian tube.
5. Water in sinuses - particularly the sphenoidal and maxillary sinuses (Svechnikov's sign).
6. Diatoms in lung, liver, kidneys, bone marrow - the diatom test (Nile blue method) - the most conclusive scientific test for antemortem drowning.
7. Hemorrhages in temporal bone mastoid cells (bleeding into mastoid air cells) - Niles' hemorrhage.
8. Blood changes: In freshwater drowning - hemodilution (low chloride, low hemoglobin, low RBC count), hemolysis. In saltwater drowning - hemoconcentration (elevated chloride, elevated osmolality).

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c) Types of Drowning [4 marks]

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d) Differentiate Fresh-water vs Sea-water Drowning (Lungs and Heart) [5 marks]

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Q.3 - Adult male from fresh water pond; Froth at mouth, weed in hand; Wet vs Dry drowning; External & Internal PM findings; Diatom test [2+5+3=10] - Jhargram Govt. MC

i) Wet Drowning vs Dry Drowning [2 marks]

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ii) External and Internal PM Findings of Fresh-water Drowning [5 marks]

1. Froth - Fine, white, leathery, tenacious, mushroom-shaped froth at the mouth and nostrils (pathognomonic when present).
2. Cadaveric spasm (death grip) - Weeds, grass, sand, mud clutched tightly in the hands. This is the surest sign of antemortem drowning.
3. Cutis anserina - Goose skin from cold water.
4. Washerwoman's skin - Maceration, wrinkling, bleaching of palms and soles.
5. Postmortem lividity - Usually on anterior surface (face down in water); may be pink/red if cold water.
6. Abrasions/injuries - From water currents, rocks, propeller injuries (may be post-mortem).
7. Bloating/decomposition - If body floated for a time: greenish discoloration, skin slipping.
8. Nibbled wounds - From aquatic fauna (crabs, fish) around soft parts (eyelids, lips, nose, ears, genitalia) - postmortem.

1. Lungs:
   • Ballooned and overdistended, filling the entire thoracic cavity, overlapping the heart.
   • Pale pink or pale grey in color (vessels compressed).
   • Rib grooves/impressions on lateral surfaces (from ribs).
   • Weight approximately doubled (600-800g each, normal: 350-500g).
   • Emphysema aquosum - watery frothy fluid on cut surface.
   • Paltauf's hemorrhages - pale pink/bluish subpleural hemorrhages.
   • "Doughy" consistency, pitting on pressure.
2. Stomach: Contains water, sand, mud, weeds, foreign material (ingested during struggling).
3. Trachea and bronchi: Frothy fluid throughout.
4. Sphenoidal and other air sinuses: Contain drowning fluid.
5. Middle ear: Water present.
6. Mastoid cells: Hemorrhages (Niles' hemorrhage).
7. Blood: Hemodiluted, hemolyzed - dark, watery, thin blood; right heart engorged.
8. Brain: Edematous, congested.
9. All viscera: Congested.
10. Histology: Diatoms in alveoli, interstitium, blood vessels; sand particles in secondary bronchioles.

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iii) Medicolegal Significance and Practical Limitations of Diatom Test [3 marks]

• Diatoms are unicellular algae with rigid silica (SiO₂) shells called frustules that resist decomposition and heat.
• In antemortem drowning, diatoms enter the bloodstream through ruptured alveolar walls → circulate → deposit in organs (liver, kidneys, brain, bone marrow).
• Finding diatoms in bone marrow is particularly significant as they can only reach there via the circulation during life.
• Matches diatoms from organs with diatoms from the water source → identifies site of drowning.
• Positive test = very strong evidence of antemortem drowning.
• Test: Acid digestion method (destroy organic matter with concentrated HNO₃, centrifuge, examine residue under microscope).
• A match of diatom species between body and suspected water confirms drowning.

1. False positives - Diatoms are ubiquitous (air, food, drinking water) so may be found in non-drowning deaths.
2. False negatives - Dry drowning, early drowning, or drowning in water with few diatoms (distilled water, swimming pools with chlorine) may give negative results.
3. Decomposition - Bodies retrieved late may lose diatom evidence (though frustules themselves resist decomposition).
4. Contamination - Lab contamination with environmental diatoms is a serious problem.
5. Saltwater - Marine environments have abundant diatoms; positive result in bone marrow of saltwater drowning is more diagnostically reliable.
6. Skill required - Requires expertise and comparison with control water samples.
7. No standardized threshold - No agreed number of diatoms considered diagnostic.

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Q.4 & Q.14 - Body recovered from the sea; Sea drowning scenario with nibbled wounds, froth, voluminous lungs, sand in bronchioles, rice in stomach [NRS Medical College / SANAKA]

i) Cause of Death + Pathology [2+4 = 6 marks]

1. Seawater is aspirated into alveoli.
2. Due to osmotic gradient, fluid is drawn from the blood into the alveoli (osmotic transudation).
3. This causes hemoconcentration (elevated plasma protein, elevated Na⁺, Cl⁻, Mg²⁺).
4. Alveoli fill with fluid → pulmonary edema (oedema aquosum) - lungs become waterlogged.
5. Reduced oxygen diffusion → progressive hypoxia and CO₂ retention.
6. The hypertonic fluid also causes capillary damage and protein leakage in the lungs.
7. Death from combined asphyxia and cardiac arrest (slower than freshwater, ~8-12 min).
8. Voluminous lungs with rib impressions = emphysema aquosum from retained fluid and valvular obstruction.
9. Sand particles in secondary bronchioles = antemortem aspiration - a histological proof of antemortem drowning.
10. Water + sand + rice in stomach = swallowed during struggle = antemortem.

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ii) Contribution of Injuries in Causing Death [4 marks]

1. Pale yellowish color (no vital reaction/hemorrhage).
2. Irregular nibbled edges (characteristic of fish/crab bites, not trauma).
3. Distribution on soft exposed parts (eyes, lips, nose, feet).
4. No underlying bruising or bleeding.

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iii) Time Since Death + How Arrived At [1+4 = 5 marks]

1. No postmortem lividity visible - PM lividity normally appears within 1-2 hours and fixes in 6-12 hours. Absence suggests body was in water and turning prevented fixation, OR very early.
2. Bluish discoloration on right flank - early decomposition/lividity change, suggesting body floating with right flank uppermost.
3. Maceration of skin (implied by findings in water) - skin maceration begins after 2-4 hours in warm water.
4. Identifiable rice particles in stomach - rice is generally digested within 2-4 hours. Identifiable rice suggests death within ~2-4 hours of the last meal (4 hours after dinner = rice still partially identifiable).
5. Rigor mortis - state not mentioned, but in May (hot climate), rigor may have passed in 24-36 hours.
6. Water temperature and season - warm water accelerates decomposition and shortens the floating period.
7. Sand in secondary bronchioles confirmed antemortem aspiration.

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Q.5 - Female aged 22 found hanging from ceiling; Intact ligating material; Causes of death; External and internal findings; Neck incision; Materials to preserve; Sexual asphyxia [15 marks] - KPC Medical College, Jadavpur

a) Causes of Death in Hanging

1. Asphyxia (most common) - compression of airway and obstruction to breathing.
2. Venous obstruction - jugular veins compressed → cerebral congestion → unconsciousness and brain death.
3. Arterial obstruction - carotid arteries compressed → rapid cerebral ischemia (loss of consciousness in 8-15 seconds).
4. Reflex cardiac arrest (vagal inhibition) - pressure on the carotid sinus → reflex vagal cardiac arrest.
5. Fracture-dislocation of cervical vertebrae with cord transaction - in judicial hanging with a long drop (causes "hangman's fracture" at C2-C3). Not in typical suicidal hanging.
6. Combined mechanisms - usually asphyxia + venous obstruction together.

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b) Important External Findings in Hanging

1. Ligature mark (furrow/groove):
   • Oblique/parchment-like, pale yellowish-brown, dry, hard.
   • Runs from below the chin upward toward the knot (inverted V-shape).
   • Usually above the thyroid cartilage (in typical hanging).
   • Incomplete - does not encircle the neck completely (gap at the knot).
   • Parchmentization of the groove - drying of abraded skin.
   • Congestion/petechiae above and below the groove.
2. Face: Pale (in typical hanging with carotid obstruction) or congested/cyanosed.
3. Eyes: Petechial hemorrhages in conjunctiva.
4. Tongue: Protruded and bluish.
5. Mouth: Frothy discharge; salivary dribble on chin and chest.
6. Hands: Clenched.
7. Feet and legs: Tardieu's spots (dependent petechiae from lividity).
8. Erection of penis and seminal discharge in males (due to pressure on spinal cord/reflex).
9. Urine and feces passed.

c) Internal Findings in Hanging

1. Neck dissection:
   • Soft tissue under ligature: white, hard, glistening (no hemorrhage in simple hanging).
   • Neck muscles: minimal bruising (unlike throttling).
   • Hyoid bone fracture - seen in approximately 25-40% of hanging cases (more in older individuals where bone is ossified).
   • Thyroid cartilage fracture - rare in hanging.
   • Intimal tears in carotid arteries at the site of compression (when present - "SIMON'S sign" or "PONSOLD'S sign").
   • Hemorrhage in sternomastoid (Musgrave and Seibert's sign).
2. Brain: Congested/pale depending on mechanism.
3. Lungs: May show Tardieu's spots; congested. Not as overdistended as drowning.
4. Spinal cord: Damage at C2-C3 in judicial hangings.
5. Viscera: Congested, petechial hemorrhages throughout.

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d) Which Incision is Used for Neck in Autopsy?

1. Standard "Y" or "T" incision is modified - the neck structures are dissected AFTER draining all the blood from the head and thorax.
2. The preferred technique is: First reflect the scalp, open the skull and remove the brain → then drain the chest and abdomen → LASTLY dissect the neck in a bloodless field.
3. Embalming-first technique - some recommend brief embalming before neck dissection to prevent artifact hemorrhages.
4. The standard "layered dissection technique" of the neck - dissect layer by layer from anterior, examining each structure separately.
5. In practice: The modified "Y" incision extending to the mastoid process bilaterally, or a horizontal neck incision below the clavicles connecting with the standard incision.

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e) Materials to Preserve in Autopsy of Hanging with Sexual Assault History

1. Viscera in toto - stomach with contents (for chemical analysis), liver (100g), kidney (each separately), brain, spleen in rectified spirit (not formalin for chemical exam).
2. Blood - 30 mL in plain tube and EDTA tube.
3. Urine - if present in bladder.
4. Hair - scalp and pubic hair (for DNA/comparison).
5. Nail clippings - for DNA of attacker.
6. Vaginal/cervical swabs - for semen (spermatozoa, prostate-specific antigen).
7. High vaginal swab + vulval swab - for evidence of sexual assault.
8. Rectal swab - if anal assault suspected.
9. Clothing - preserved intact in separate bags.
10. Ligature material - intact, preserved for FSL.
11. Photographs of all injuries.
12. Blood for DNA - and comparison with any seminal material found.

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f) What is Sexual Asphyxia?

• Almost exclusively males, usually adolescents or young adults.
• Found alone, in a private place (locked room, wardrobe).
• Nude or partially nude, sometimes cross-dressed.
• Ligature around neck attached to a release mechanism (the person intends to release before dying).
• Pornographic material nearby.
• The ligature mark may show antemortem petechiae but no suicidal note.
• The release mechanism fails, leading to death.
• Manner of death: Accidental (not suicidal).
• May be confused with suicidal hanging.

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Q.6 - Known drunkard found dead beside drain, head in drain; Causes; Autopsy findings; Pathophysiology of fresh vs saltwater drowning; Hydrocution [2+5+6+2=15] - Sarat Chandra Chattopadhyay Govt. MC

a) Possible Cause of Death [2 marks]

1. Drowning in shallow water - alcohol causes sedation and loss of protective reflexes; the person collapsed face-first into the drain. Even 2-5 cm of water can cause drowning if the face is submerged.
2. Hydrocution (immersion syndrome) - reflex cardiac arrest from sudden contact of cold water with face/body.
3. Natural disease (acute cardiac/cerebrovascular event) causing collapse, followed by incidental head-in-water position.
4. Combined alcohol toxicity + positional asphyxia - in the prone position, the chest cannot expand.

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b) Autopsy Findings [5 marks]

• No injuries detected externally.
• Blood alcohol level on chemical analysis would confirm intoxication.
• The drain water should be sampled for diatom comparison.

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c) Pathophysiology - Freshwater vs Saltwater Drowning [6 marks]

1. Freshwater enters alveoli → rapidly absorbed into the pulmonary circulation by osmosis (water moves from alveoli → blood).
2. Rapid hemodilution → blood volume increases by up to 50%.
3. Hyponatremia, hypomagnesemia, dilution of plasma proteins.
4. Hemolysis - RBCs lyse due to osmotic stress → releases K⁺ → hyperkalemia.
5. Hyperkalemia → ventricular fibrillation → cardiac arrest.
6. Simultaneously, massive dilution + hemolysis → acute anemia.
7. Surfactant washout → alveolar collapse, V/Q mismatch.
8. Death from VF in 3-5 minutes.
9. Lungs appear bulky, pale, light.

1. Seawater enters alveoli → fluid drawn from blood INTO alveoli by osmosis (blood → alveoli).
2. Hemoconcentration → blood volume decreases.
3. Hypernatremia, hypermagnesemia, elevated plasma protein, hyperchloremia.
4. Alveoli fill with protein-rich fluid → pulmonary edema (oedema aquosum).
5. Magnesium excess → bradycardia, cardiac depression.
6. Progressive hypoxia from flooding of alveoli → cardiac arrest.
7. Death takes longer (8-12 min) than freshwater drowning.
8. Lungs appear heavy, congested, waterlogged.

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d) What is Hydrocution? [2 marks]

• Minimal or absent froth.
• Lungs not overdistended.
• Stomach may not contain water.
• Signs of cardiac arrest (right heart engorgement).
• No signs of struggle in the water.
• This is essentially "dry drowning" triggered by cold water.

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Q.7 - 26yr married woman, horizontal ligature mark below thyroid, petechiae, crescentic abrasions on chin/cheek, scratch marks on forearms, influential husband requesting suicidal certificate [3+4+4+2+2=15] - IPGME&R / SSKM

a) Most Likely Nature and Manner of Death [3 marks]

1. Crescentic abrasions on chin and cheek - fingernail marks from the assailant holding/gripping the victim's face to restrain her. Classic sign of a struggle against manual force.
2. Petechiae in palpebral conjunctivae - strongly suggest asphyxia with venous obstruction (more prominent in strangulation than hanging).
3. Linear vertical scratch marks on both forearms - defensive wounds (victim scratching her own forearms during struggle/restraint) or struggle marks.
4. Deep cyanosis of face and lips with blood-stained froth - marked facial congestion typical of strangulation (not typical of typical hanging).

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b) Specialised Autopsy Steps for Neck Dissection + Prevention of Artifacts [4 marks]

1. Complete external examination first - photograph all injuries in situ before touching.
2. Total body X-ray (if available) before incision.
3. Embalming/Fixation protocol - some authorities recommend dissection in formalin-fixed state to prevent artifact hemorrhage, but this requires delay.
4. Standard sequence: Skull/brain → chest and abdomen → NECK LAST, in a bloodless field.
5. Neck dissection technique:
   • Remove brain and drain intracranial blood completely first.
   • Open chest, drain thoracic blood.
   • Only then begin neck dissection.
   • Dissect layer by layer, anteriorly to posteriorly.
   • Examine each structure under magnification.
   • Separate and individually examine: strap muscles, carotid sheaths, hyoid bone, thyroid cartilage, cricoid, trachea.
6. Document everything: Exact position, depth, color of any hemorrhage.
7. Avoid pulling during scalp reflection - common cause of artifact petechiae in scalp and neck.
8. Collect deep neck muscle samples separately for histology.

• Do not attempt neck dissection on an unemptied, blood-filled specimen - blood tracks under pressure into neck planes mimicking bruises.
• Layered sharp dissection (not blunt) prevents tearing that creates artificial hemorrhage.
• Sample hemorrhagic areas for histology - vital reaction (leucocyte infiltration) confirms antemortem origin.
• Do not press on the neck during examination.
• Histopathology is the gold standard to distinguish antemortem from artifact hemorrhage (vital reaction present in antemortem).

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c) Critical Internal Findings Expected in Ligature Strangulation [4 marks]

1. Neck deep structures:
   • Hemorrhage in strap muscles (sternohyoid, sternothyroid, omohyoid).
   • Hyoid bone fracture (greater cornu) - MORE COMMON in throttling but also in ligature strangulation.
   • Thyroid cartilage fracture - more common in strangulation than hanging.
   • Intimal tears in carotid arteries.
   • Hemorrhage around the carotid sinus.
2. Tracheal and laryngeal mucosa: Congested, hemorrhagic.
3. Lungs:
   • Markedly congested and edematous.
   • Tardieu's spots (subpleural petechial hemorrhages) - abundant on visceral pleura.
   • Frothy, blood-stained fluid in bronchi.
4. Pericardium: Tardieu's spots on visceral pericardium.
5. Brain: Congested, edematous, petechiae in white matter; cerebral vessels engorged.
6. Heart: Right side dilated, engorged with dark fluid blood. Left side relatively empty.
7. Viscera: General venous congestion.
8. Blood: Dark, fluid (unclotted) due to asphyxial death.
9. Stomach: Possible vomitus (aspiration from struggling/obstruction).
10. Uterus: If the victim is female, vaginal examination may reveal signs of sexual assault.

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d) Ethical Conflicts and Communication Response [2 marks]

1. Beneficence vs. Non-maleficence - falsifying the certificate would harm the deceased (justice denied) and society.
2. Autonomy of the dead vs. coercion - the dead have a right to proper investigation.
3. Professional integrity vs. social pressure from influential person.
4. Dual loyalty - pressure to serve the family vs. obligation to serve justice/truth.

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e) Relevant BNS Sections and Immediate Legal Duty [2 marks]

• Section 103 BNS (Murder) - if homicidal strangulation is confirmed.
• Section 108 BNS (Abetment of suicide) - if proven otherwise.
• Section 318 BNS (Causing death by negligence) - if applicable.

• Section 194 BNSS - Mandatory inquest by Magistrate in cases of suspicious/unnatural death.
• Section 176 BNSS (equivalent to old Section 174 CrPC) - Police inquest.

1. Do NOT issue a death certificate in an unnatural/suspicious death without postmortem examination.
2. Immediately inform the Police about the suspicious circumstances and physical findings.
3. Preserve the body intact with the ligature material in situ.
4. Document all findings contemporaneously and accurately.
5. Refuse to comply with any request to falsify records - this is punishable under Section 197 BNS (falsification of documents by public servant).
6. Conduct a full medicolegal autopsy as directed by competent authority (Magistrate).

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Q.8 & Q.10 - Male 35 years, May, transverse ligature mark middle of neck, bleeding from nose and ears, fecal/urinary discharge, marked asphyxia, rigor mortis fully established; No ligature material [1+2+5+2=10] - Rampurhat Govt. MC

a) Probable Cause of Death [1 mark]

• Transverse ligature mark encircling the middle of the neck = horizontal, complete encirclement = strangulation, NOT hanging.
• Marked signs of asphyxia.
• No ligature material found = strongly suggests homicide (assailant removed the ligature after death).

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b) Probable Time Since Death [2 marks]

• Appears: 1-2 hours
• Fully established: 4-6 hours
• Disappears: 12-18 hours (in summer due to heat)

• Bleeding from nose and ears = venous back-pressure from strangulation (antemortem sign), not time-related.
• Fecal and urinary discharge = relaxation of sphincters at/after death.
• No mention of decomposition = relatively recent death.

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c) Probable Findings on Neck Dissection [5 marks]

1. Subcutaneous tissue under the ligature mark:
   • Reddish, ecchymosed (unlike hanging where it is white and hard).
   • Hemorrhagic infiltration of tissues under the mark.
2. Strap muscles:
   • Bruising and hemorrhage in sternohyoid, sternothyroid muscles.
3. Hyoid bone:
   • Fracture of the greater horns (cornu) of hyoid - more common in strangulation. Look for fracture at the junction of body and greater cornua.
4. Thyroid cartilage:
   • Fracture of thyroid cartilage (superior/inferior cornua; lamina) - more common than in hanging.
5. Cricoid cartilage:
   • May be fractured.
6. Carotid arteries:
   • Intimal tears (longitudinal) in internal carotid arteries.
   • Perivascular hemorrhages.
7. Carotid sinus region:
   • Hemorrhages.
8. Jugular veins:
   • Engorged.
9. Larynx and trachea:
   • Mucosal congestion, petechiae, edema.
10. Deep cervical lymph nodes:
    • Congested and enlarged.

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d) Tests from the Site of Ligature Mark [2 marks]

1. Swabs for DNA - from within the groove (traces of the assailant's DNA from the ligature material rubbed against skin).
2. Fiber examination - microscopic examination and FSL analysis of any fibers embedded in the groove to identify the ligature material type (nylon, cotton, jute, etc.).
3. Photography + measurement - exact width, depth, pattern of the groove (to match with ligature material).
4. Histopathological examination (skin biopsy from the groove edge):
   • To confirm vital reaction (neutrophil infiltration, hyperemia) = antemortem origin.
   • To distinguish from postmortem ligature artifact.
5. Chemical/luminol test - if blood is present.
6. The adipocere test - if late case.
7. Infrared photography - to reveal faint marks not visible to naked eye.

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Q.9 - Define Drowning; Pathophysiological changes in Fresh-water drowning; Differentiating antemortem drowning from postmortem submersion; Mechanism of hemorrhagic spots in hanging and drowning [2+5+4+4=15] - Jagannath Gupta Institute

i) Definition of Drowning [2 marks]

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ii) Pathophysiological Changes in Fresh-water Drowning [5 marks]

• Fresh water → hypotonic → absorbed into blood → hemodilution → hemolysis → hyperkalemia → VF → death.
• Surfactant washout → atelectasis.
• Changes in blood: decreased Cl⁻, Na⁺; decreased Hb, RBC; elevated K⁺; decreased plasma osmolality.
• Lungs: pale, bulky, overdistended.
• Time to death: 3-5 minutes.

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iii) Differentiate Antemortem Drowning from Postmortem Submersion [4 marks]

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iv) Mechanism of Formation of Hemorrhagic Spots (Tardieu's Spots) in Hanging and Drowning [4 marks]

• Ligature compresses the neck → jugular vein obstruction (veins occlude at lower pressure than arteries).
• Arterial blood continues flowing into the head.
• Venous back-pressure increases dramatically in capillaries of the face, conjunctiva, brain surface, serosal surfaces.
• Capillary walls cannot withstand the increased hydrostatic pressure → rupture → petechial hemorrhages.
• Location: Subconjunctival, palpebral conjunctiva, face, brain surface (subpial), subpleural, subpericardial.
• Less common in typical hanging (because carotid arteries are also compressed → less arterial input). More common in atypical hanging and strangulation.

• Asphyxia → hypoxia → increased CO₂ → capillary dilation and increased capillary permeability.
• Simultaneously, violent respiratory efforts against a closed airway → marked increase in intrathoracic pressure → compresses pulmonary capillaries, forcing blood backward.
• Forced inspiratory efforts against water → rupture of alveolar walls → interstitial hemorrhages within lung = Paltauf's hemorrhages (these are the "hemorrhagic spots" specific to drowning).
• On the subpleural surface: Tardieu's spots from the same mechanism.
• Additionally: venous engorgement from asphyxia contributes to subpleural and pericardial petechiae.

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Q.11 - Define Asphyxia; Cardinal Signs; External and Internal findings in Drowning [1+3+6=10] - Malda Medical College

Define Asphyxia [1 mark]

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Cardinal Signs of Asphyxia [3 marks]

1. Cyanosis - bluish discoloration of lips, tongue, fingernails, and mucous membranes due to excess reduced hemoglobin in capillaries.
2. Congestion - deep venous congestion of face, neck, conjunctivae; dark, congested viscera.
3. Petechial hemorrhages (Tardieu's spots) - pinpoint hemorrhages on subconjunctiva, palpebral conjunctiva, serosal surfaces of pleura, pericardium, brain surface. Classical feature of asphyxia.
4. Edema - cerebral and pulmonary edema from hypoxic damage and venous back-pressure.
5. Right ventricular dilatation - right heart engorged with dark fluid blood (venous obstruction → right heart backed up).
6. Dark fluid blood - blood remains unclotted and dark (reduced hemoglobin).
7. Rapid loss of consciousness and rapid death.

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External and Internal PM Findings in Drowning [6 marks]

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Q.12 - Types of Asphyxia; Asphyxia Stigmata [7+3] - P.C.SEN, ARAMBAGH

Types of Asphyxia [7 marks]

1. Hanging - suicidal (most common), homicidal, accidental
2. Strangulation - ligature, manual (throttling), mugging, garroting, bansdola
3. Suffocation:
   • Smothering (closure of nose and mouth) - including overlaying, burking
   • Gagging
   • Choking (foreign body in airway)
   • Café coronary
   • Traumatic asphyxia (chest compression)
4. Drowning - wet, dry, secondary, immersion syndrome
5. Positional asphyxia - death due to body position preventing breathing
6. Overlying - infant overlaid by sleeping adult

• Obstruction from natural disease (laryngeal edema, epiglottitis, diphtheritic membrane)

• CO poisoning, cyanide poisoning, hydrogen sulfide

• Breathing in oxygen-deficient atmosphere (miners' asphyxia)

• Displacement of oxygen by non-toxic gases (CO₂, methane, nitrogen)

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Asphyxia Stigmata [3 marks]

• Cyanosis of lips, tongue, fingernails
• Congestion of face
• Petechiae - subconjunctival, conjunctival
• Facial edema

• Petechial hemorrhages (Tardieu's spots) on serosal surfaces of pleura, pericardium, peritoneum
• Petechiae in brain (white matter and pia-arachnoid)
• Congested lungs, dark blood
• Right heart dilatation with dark fluid blood
• Generalized visceral congestion
• Pulmonary and cerebral edema

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Q.12 (Raiganj) - Define Mechanical Asphyxia; Classify; Differences between Hanging and Strangulation [1+4+5=10]

Define Mechanical Asphyxia [1 mark]

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Classification of Mechanical Asphyxia [4 marks]

1. Hanging (typical, atypical; complete, partial; suicidal, homicidal, accidental)
2. Strangulation (ligature, manual/throttling, mugging, garroting, bansdola, palmer)
3. Suffocation (smothering, gagging, choking, traumatic asphyxia, overlying, burking)
4. Drowning (wet, dry, secondary, immersion syndrome)
5. Positional asphyxia
6. Neck hold strangulation (mugging)

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Differences: Hanging vs Strangulation [5 marks]

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Q.13 - Define Asphyxia; Cardinal Signs; External and Internal Findings in Throttling [10] - SANTINIKETAN

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Q.15 - Define Drowning; Types; PM Findings in Drowning; Surest Sign; Oedema Aquosum [2+2+3+1+2] - ESIC JOKA

What is Oedema Aquosum? [2 marks]

• Distinguished from emphysema aquosum (active respiratory effort + water + mucus = froth).
• The lungs are heavy, waterlogged, not frothy.
• Seen in bodies dumped into water after death or victims who were deeply unconscious.

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Q.16 - 19yr Sexually Assaulted Woman Who Hanged Herself; Parchmentized Ligature Mark; Tardieu's Spots [1+2+3+4+2+3=15] - BMC

i) Section of BNSS for Inquest [1 mark]

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ii) Define Inquest [2 marks]

1. Police Inquest - conducted by the Officer In-Charge of a Police Station (Section 193 BNSS / formerly 174 CrPC). For all unnatural deaths.
2. Magistrate's Inquest - conducted by Executive Magistrate (Section 194 BNSS / formerly 176 CrPC). Mandatory in cases of deaths in police custody, dowry deaths (woman dying within 7 years of marriage), and other specified circumstances.
3. Coroner's Inquest - Under the Coroners Act 1871. Applicable only in certain cities (Kolkata in West Bengal).

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iii) Other Types of Autopsies besides Medicolegal Autopsy [3 marks]

1. Clinical/Hospital/Therapeutic Autopsy (Pathological Autopsy) - to determine cause of disease/natural death; for academic and research purposes; requires consent of relatives; findings remain confidential.
2. Academic/Research Autopsy - to advance medical knowledge; conducted on donated bodies.
3. Anatomical Dissection - on donated cadavers for teaching anatomy (not a true autopsy).
4. Military Autopsy - on soldiers killed in action.
5. Exhumation Autopsy - after body has been buried (Section 176 BNSS).
6. Pauper's Autopsy - on unclaimed bodies.

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iv) Mechanism of Formation of Tardieu's Spots [4 marks]

1. Asphyxia begins → rising CO₂ + falling O₂ in blood.
2. Rising CO₂ → capillary dilatation (CO₂ is a potent vasodilator) and increased capillary permeability (hypoxia damages endothelium).
3. Venous obstruction (in hanging, strangulation) or venous engorgement (in asphyxia) → increased hydrostatic pressure in capillaries above the site of obstruction.
4. Violent respiratory efforts in dying phase → markedly increased intrathoracic and intraabdominal pressure → transmitted to pulmonary capillaries.
5. Overdistended, fragile capillaries rupture → small hemorrhages appear under serosal surfaces = Tardieu's spots.
6. They represent the last violent struggle for life before death.

• Named after Professor A.A. Tardieu (French medico-legal expert, 1855).
• They are NOT specific to asphyxia - can occur in any cause of acute death (but most prominent in asphyxia).
• Subpleural location (visceral pleura) is classical.
• Size: pinpoint to a few millimeters.
• Differentiated from Paltauf's hemorrhages (drowning-specific, larger, interstitial, lung parenchyma).

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v) Parchmentization [2 marks]

• After death, the abraded/compressed skin at the ligature groove loses moisture by evaporation.
• The skin becomes hard, dry, yellowish-brown, and leathery in appearance - resembling parchment paper.
• This is a postmortem change occurring due to desiccation of the exposed dermal tissues.
• It is seen in hanging (where the ligature mark is superficially abraded and exposed to air).
• It is an important medicolegal sign because it can persist long after death and helps identify the ligature mark.
• Unlike vital reactions (antemortem hemorrhage into grooves), parchmentization itself is postmortem, but the abrasion producing it was made during life.
• Must be distinguished from postmortem ligature artifacts (e.g., ligature placed postmortem shows no vital reaction histologically).

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vi) Viscera Preservation Protocol for FSL in This Case [3 marks]

1. Stomach + contents - entire stomach with its contents (100g minimum) - in spirit.
2. Liver - 100-200g - in spirit.
3. Kidney (one complete) - in spirit.
4. Spleen - in spirit.
5. Brain - in spirit.
6. Blood - 30 mL (plain + EDTA tubes) - refrigerated (no preservative).
7. Urine - if available - in a sterile container.

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SHORT NOTES & EXPLANATIONS (5 & 4 Marks)

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1. Hyoid Bone Fracture is More Common in Manual Strangulation than in Hanging [Calcutta National MC / Raiganj]

• The assailant's fingers directly compress the neck in the region of the hyoid bone and thyroid cartilage.
• Direct, localized, forceful pressure is applied to the hyoid (at the level of the digits).
• The greater horns (cornua) of hyoid are fractured at their junction with the body.
• Hyoid fracture occurs in approximately 40-50% of throttling cases.
• In younger adults (hyoid is partially cartilaginous and less brittle) - less common.
• In older adults (ossified, brittle) - more common.

• The ligature applies pressure mainly at or above the thyroid cartilage.
• The force is more diffuse and distributed across the width of the ligature.
• The ligature typically lies at the level of the thyroid cartilage or above it (in typical hanging), not directly over the hyoid.
• Less direct, less forceful focused compression of the hyoid.
• Hyoid fracture occurs in only approximately 25-40% of hanging cases.

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2. Drowning in Fresh Water Causes Earlier Death than Salt Water Drowning [College of Medicine & Sagore Dutta / P.C.SEN Arambagh]

• Fresh water drowning: Death occurs in approximately 3-5 minutes.
• Salt water drowning: Death occurs in approximately 8-12 minutes.

1. Rapid hemodilution: Fresh water (hypotonic) is rapidly absorbed into the blood from alveoli → blood volume increases by up to 50% within 2-3 minutes.
2. Massive hemolysis: The hypotonic plasma lyses RBCs rapidly → releases intracellular potassium (K⁺) into plasma → acute hyperkalemia.
3. Ventricular fibrillation: Hyperkalemia rapidly causes VF → irreversible cardiac arrest within 3-5 minutes.
4. Combined anemia + VF = rapid irreversible cardiac death.

1. Sea water is hypertonic → fluid shifts from blood to alveoli (osmotic transudation) → slower process.
2. Hemoconcentration develops gradually.
3. Death from progressive hypoxia and cardiac depression (from magnesium and hypernatremia).
4. No rapid VF mechanism - slower cardiac deterioration.

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3. Partial Hanging Considered to be Suicidal unless Proved Otherwise [Jalpaiguri Govt. MC]

1. Very small force is required: The weight of only the head (approximately 5-6 kg) is sufficient to occlude the neck vessels and airways. Suicidal persons often lie down or kneel with the ligature around the neck.
2. Accidental partial hanging is rare but possible (more in children, intoxicated persons).
3. Homicidal partial hanging is extremely rare because:
   • A person would resist and struggle.
   • The victim could easily stand up or relieve the pressure.
   • For homicide, complete suspension or manual strangulation is more practical for the assailant.
4. Historical/statistical evidence: The vast majority of partial hanging cases at autopsy are confirmed suicides.
5. Exceptions (when it may not be suicidal):
   • Children (accidental - caught in crib rail, swing rope).
   • Intoxicated persons (accidental).
   • Restrained persons (rare homicide).
   • Signs of struggle or other injuries suggesting homicide.
6. Medicolegal importance: Police/court must present positive evidence of homicide to override this presumption.

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4. A Ligature Mark May be Absent in a Case of Death Due to Hanging [R.G. Kar Medical College]

1. Soft, wide ligature material: Broad, soft materials (folded cloth, towel, scarf, bedsheet) distribute pressure over a wide area without producing a deep groove. The mark may be barely visible or absent.
2. Decomposition: Advanced decomposition destroys the skin surface, obliterating the groove.
3. Bloated/edematous neck: Severe post-mortem swelling can efface a shallow groove.
4. Very short hanging time: If the body was cut down immediately after death or before death (e.g., attempted rescue), the mark may be faint.
5. Soft, padded material: If the noose was padded.
6. Body in water: Prolonged immersion causes maceration and washing out of the groove.
7. Child/infant: Pliable soft tissue may not retain marks well.
8. Obese individuals with thick neck fat.

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5. Burking [Sarat Chandra Chattopadhyay Govt. MC]

• No ligature marks.
• No external injuries (or very few - fingernail marks on face if mouth covered by hand).
• Internal signs of asphyxia: cyanosis, petechiae, congestion.
• Slight hemorrhage on the face occasionally.
• May leave very few marks detectable at autopsy.
• Classically a homicidal method.
• Burke was hanged; Hare turned King's evidence.

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6. Absence of Water in the Stomach Does NOT Exclude Drowning [Raiganj]

1. Dry drowning: Death is from laryngospasm - no water enters the lungs or stomach. The victim dies before water can be swallowed.
2. Immersion syndrome (hydrocution): Death is from sudden cardiac arrest - no water swallowed.
3. Decomposition: Post-mortem liquefaction and decomposition gases may expel stomach contents, including water.
4. Short survival after drowning: If death is very rapid (intense laryngospasm), the person may not swallow any water.
5. Postmortem drainage: During recovery and transport of the body, stomach water may drain out.
6. Vomiting during drowning: The victim may have vomited all swallowed water.

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7. Absence of Froth Does NOT Rule Out Antemortem Drowning [IQ CITY]

1. Dry drowning: No water enters alveoli - no froth formed.
2. Oedema aquosum: Unconscious victims fill lungs passively with water without making active respiratory efforts - no froth, only fluid flooding.
3. Decomposition: Froth disappears with decomposition.
4. Rapid/early recovery of the body: Froth may not yet have formed or may have dispersed.
5. Very cold water: Reduces respiratory effort intensity.
6. No surfactant available: Neonates/very premature individuals may lack sufficient surfactant.
7. Delayed examination: Froth dries and disappears if body is out of water for several hours.
8. Body positioned differently post-recovery.

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8. Fracture of Hyoid Bone is More Common in Throttling than Hanging [Raiganj]

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Sources cited throughout:

• The Essentials of Forensic Medicine and Toxicology, 36th Edition (2026) by K.S. Narayan Reddy (ISBN: 9789366165257) - pp. 141-145, 150-155, 359-375
• P.C. Dikshit Textbook of Forensic Medicine and Toxicology (ISBN: 9788188867967) - pp. 291-310, 11793-13471
• Parikh's Textbook of Medical Jurisprudence, Forensic Medicine and Toxicology (ISBN: 9789388902267) - pp. 2319-3330

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1. In strangulation vs hanging tables - always mention "ligature mark is the key differentiator."
2. Diatom test - always mention both ML significance AND limitations.
3. For Q.7 type SSKM/IPGME&R questions - structure your answer clearly under each sub-part (a, b, c, d, e).
4. BNS/BNSS sections frequently asked: Section 103 BNS (murder), Section 194 BNSS (Magistrate inquest), Section 193 BNSS (Police inquest).
5. Always include cadaveric spasm = surest sign of antemortem drowning in every drowning question.
6. For May/summer rigor mortis TSD - rigor fully established and retained = 6-12 hours before autopsy in hot climate.The complete WBUHS exam-oriented answers for all Chapter 5 Asphyxial Deaths questions are above. Here is a quick summary of what was covered:

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• Q.1 (Bankura): Types of strangulation + throttling autopsy findings + Lynching
• Q.2 (Deben Mahata): Inquest holder + antemortem drowning signs + types + freshwater vs seawater (lungs & heart)
• Q.3 (Jhargram): Wet vs dry drowning + freshwater PM findings + diatom test limitations
• Q.4/Q.14 (NRS/SANAKA): Sea drowning pathology + injury contribution + time since death
• Q.5 (KPC Jadavpur): Causes of death in hanging + findings + neck incision + viscera preservation + sexual asphyxia
• Q.6 (Sarat Chandra): Drunkard/drain death causes + autopsy + freshwater vs saltwater pathophysiology + hydrocution
• Q.7 (SSKM/IPGME&R): Throttling vs hanging differentiation + specialized neck autopsy + internal findings + ethics + BNS/BNSS sections
• Q.8/Q.10 (Rampurhat): Strangulation TSD + neck dissection findings + ligature mark tests
• Q.9 (Jagannath Gupta): Drowning definition + freshwater pathophysiology + antemortem vs postmortem submersion + Tardieu's spots mechanism
• Q.11 (Malda), Q.12 (P.C.Sen/Raiganj), Q.13 (Santiniketan), Q.15 (ESIC Joka), Q.16 (BMC): All answered with definitions, cardinal signs, stigmata, oedema aquosum, types, parchmentization, viscera preservation protocol