Autopsy: Types & Techniques

Autopsy (necropsy, post-mortem examination) is the systematic external and internal examination of a dead body to determine the cause, manner, and mechanism of death and to identify the deceased. For NEET PG, the jurisprudence around who can order an autopsy, when consent is needed, and the named dissection techniques are the recurring testable points.

Definition & basic terminology

The word "autopsy" derives from Greek autopsia ("to see for oneself"); "necropsy" literally means "viewing the dead." A post-mortem examination is conducted by a registered medical practitioner, usually a forensic pathologist, after death has been confirmed.

Key objectives:

1. Establish identity of the deceased.
2. Determine the cause of death (the disease/injury that initiated the lethal chain).
3. Establish the manner of death (natural, accidental, suicidal, homicidal, undetermined).
4. Estimate time since death (post-mortem interval).
5. Recover and preserve trace/biological evidence (bullets, viscera for chemical analysis, etc.).
6. In clinical autopsies — to correlate clinical diagnosis with pathological findings and audit medical care.

High-yield: The single most important purpose of a medicolegal autopsy is to determine the cause and manner of death and to assist the administration of justice; for a clinical/pathological autopsy, the purpose is to confirm the diagnosis and study the disease process.

Classification: Types of autopsy

Autopsies are broadly divided into two categories based on the authority ordering them and their objective.

Feature	Medicolegal (Forensic) autopsy	Clinical (Pathological/Academic) autopsy
Ordered by	Legal authority — police, magistrate, coroner	Treating doctor / hospital authority
Consent of relatives	NOT required (overriding state interest)	Mandatory written consent of next of kin
Purpose	Cause + manner of death, justice	Confirm diagnosis, study disease, audit care
Who performs	Forensic expert / authorised medical officer	Pathologist
Extent	Complete — must examine all 3 cavities	May be limited to the consented region/organs
Selection of cases	Sudden, suspicious, violent, unnatural deaths	Selected hospital deaths for study
Identity	Often unknown; identification a key step	Usually known
Report	Legal document, may be produced in court	Hospital/academic record

High-yield: In a medicolegal autopsy, consent of relatives is NOT needed and all three body cavities (cranial, thoracic, abdominal) must be opened irrespective of the apparent cause of death. In a clinical autopsy, written consent IS mandatory and examination may be restricted.

Other descriptive terms

• Verbal autopsy — establishing cause of death by interviewing relatives/caregivers about the symptoms and circumstances preceding death; used in community/epidemiological surveys where no medical certification exists.
• Psychological autopsy — retrospective reconstruction of the deceased's mental state, typically in suspected suicides, by analysing diaries, notes, and interviews with contacts.
• Negative autopsy — a complete autopsy (including histopathology, toxicology, microbiology) that fails to reveal any cause of death (≈ 2–5% of cases). Causes include vagal inhibition, certain poisons, electrocution, anaphylaxis, and air/fat embolism missed at dissection.
• Obscure autopsy — gross findings are absent or inconclusive, but ancillary investigations may still yield a cause; suggests early disease, undetected biochemical disturbance, or subtle lesions.
• Virtual autopsy (virtopsy) — non-invasive, image-based examination using post-mortem CT and MRI; increasingly used to complement (not fully replace) conventional autopsy.

Legal authority to order a medicolegal autopsy

In India, the authority to order a medicolegal autopsy rests with:

• Investigating police officer (not below the rank of a Sub-Inspector / station house officer) under provisions for inquest in unnatural death.
• Magistrate (Executive or Judicial) — e.g., in custodial deaths, deaths in police firing, dowry deaths within 7 years of marriage.
• Coroner (historically, in some metropolitan jurisdictions — coroner system now largely abolished in India).

High-yield: A doctor cannot start a medicolegal autopsy without a written authorisation/requisition and an accompanying inquest report. Conducting one without authority is unlawful.

Inquest (preliminary inquiry into cause of death)

Type of inquest	Conducted by	Typical situations
Police inquest	Police officer (SI and above)	Most unnatural deaths — accidents, suicides, homicides
Magistrate inquest	Executive/Judicial Magistrate	Custodial deaths, deaths in police action, dowry death (woman within 7 yrs of marriage, suspicious circumstances), exhumation
Coroner inquest	Coroner	Largely obsolete in India (abolished)
Medical examiner system	Qualified forensic pathologist with both investigative and medical powers	USA (not India)

High-yield: In a death of a married woman within 7 years of marriage under suspicious circumstances (suspected dowry death), the inquest must be done by a Magistrate, not merely the police.

Indications for a medicolegal autopsy

Deaths requiring medicolegal autopsy ("unnatural / suspicious" deaths):

1. All homicides, suicides, accidents (road traffic, fall, industrial, burns, drowning).
2. Sudden unexpected deaths where cause is unknown.
3. Deaths under anaesthesia / on operation table / in hospital within 24 hours of admission without diagnosis.
4. Custodial deaths, deaths in police/judicial custody, deaths in police firing.
5. Suspected poisoning.
6. Dowry deaths, deaths of women in suspicious circumstances within 7 years of marriage.
7. Decomposed/skeletonised/unidentified bodies.
8. Death due to suspected medical negligence.
9. Deaths from industrial accidents, electrocution, occupational disease.

Pre-autopsy requirements (the checklist)

Before commencing, the pathologist must ensure:

Authorisation letter → Inquest report → Dead body identification → Accompanying constable/escort with documents → Adequate daylight (preferred) → Clean, well-lit mortuary.

• The body must be positively identified (by police, relatives, or escort) and labelled with a tag.
• Autopsy should ideally be performed in good daylight, as colour changes (jaundice, bruise colour, post-mortem staining, poison-specific discoloration) are difficult to appreciate under artificial/fluorescent light. Exception: when delay would itself cause loss of evidence, e.g., decomposition.
• It should be conducted without unnecessary delay to limit decomposition and to release the body to relatives early.

High-yield: Medicolegal autopsy should be done in daylight wherever possible because artificial light alters perception of colour (e.g., bilirubin staining, bruise dating, carbon-monoxide cherry-red lividity). This is a favourite one-liner MCQ.

The autopsy procedure

External examination

Performed first, often the most evidence-rich part in a medicolegal case:

• General data: clothing (preserved as evidence), build, nutrition, identifying marks (scars, tattoos, moles, deformities).
• Post-mortem changes to estimate time since death: cooling (algor mortis), post-mortem lividity (hypostasis/livor mortis), rigor mortis, decomposition.
• Examination of natural orifices, external genitalia, and any injuries — recorded by site, size, shape, margins, and described relative to fixed anatomical landmarks.
• Trace evidence collection (hair, fibres, swabs, nail clippings).

Internal examination — the three cavities

A complete medicolegal autopsy requires opening of all three cavities: cranial, thoracic, abdominal (and the spinal canal/neck when indicated). The standard skin incision is the I-shaped or Y-shaped incision over the trunk.

Incision	Course	Use
I-shaped (straight)	Chin → symphysis pubis, midline	Most commonly used in India
Y-shaped	From each shoulder/acromion → meeting at xiphisternum → down to pubis	Cosmetically better, used where neck dissection needed; common in West
Modified Y / U-shaped	Across the chest under the breasts, used in females to avoid disfiguring the neck	Cosmetic, female bodies

The scalp is opened by a coronal (intermastoid) incision from one mastoid process to the other over the vertex, and the skull is opened with a saw to remove the calvarium and expose the brain.

Named autopsy (evisceration) techniques

This is the most heavily tested subtopic. There are four classical methods of organ removal:

Technique	Eponym	Principle
Virchow	Rudolf Virchow	Organs removed one by one, individually, as encountered
Rokitansky	Carl von Rokitansky	In-situ dissection — organs examined in place, with minimal removal (combined with partial evisceration)
Ghon (Letulle)	Ghon / Letulle	Organs removed as blocks/systems (en bloc) — cervical+thoracic, abdominal, urogenital blocks
Letulle (en masse)	Maurice Letulle	All thoracic, cervical, abdominal and pelvic organs removed together as one mass (en masse), dissected later

A simple mnemonic to fix the four methods:

Mnemonic — "Very Rich Girls Love": Virchow = organ by organ; Rokitansky = in situ; Ghon = block (en bloc); Letulle = en masse (all together).

High-yield: Distinguish carefully — Virchow = one organ at a time, Rokitansky = in situ (within the body), Letulle = en masse (whole viscera as a single mass), Ghon = organ blocks (en bloc by systems). Examiners frequently swap "in situ" and "en masse" as distractors.

When each is preferred

• Virchow — quick, good for demonstrating individual organ pathology; but disturbs anatomical relationships (interconnections lost), so less ideal where the relationship between organs (e.g., fistula, perforation tracking) matters.
• Rokitansky — useful when there is a risk of cross-contamination (e.g., infectious cases, HIV/hepatitis, anthrax) because dissection occurs in situ with minimal handling; also when the body should not be extensively eviscerated.
• Letulle (en masse) — preserves all anatomical relationships best; ideal for complex cases such as congenital cardiac anomalies, vascular lesions, and where organ interconnections must be retained. Cumbersome to handle the heavy single mass.
• Ghon (en bloc by systems) — a practical compromise, preserving relationships within each functional block while being easier to handle than a single mass.

Special procedures

Exhumation

Exhumation is the lawful digging out of an already buried body for medicolegal examination.

• Authorised only by order of a Magistrate (Executive Magistrate) in India. A doctor or police cannot order it on their own.
• Indications: fresh suspicion of foul play (poisoning, criminal negligence), identity disputes, insurance/accident claims, second opinion, disinterment for relocation.
• No statutory time limit for exhumation in India (unlike England, where it was traditionally limited; India has no time bar).
• Conducted in the presence of the Magistrate and an investigating officer, in daylight, with proper identification of the grave and body.
• Samples taken: soil from above, below, sides, and the level of the body (control samples) to exclude post-burial contamination by arsenic/heavy metals from the earth; coffin pieces; viscera for chemical analysis.

High-yield: Exhumation in India requires a Magistrate's order, has no time limit, and control soil samples must be collected from around the body to differentiate ingested poison from environmental contamination (especially arsenic and other heavy metals).

Autopsy of decomposed / skeletal remains

Focus shifts to identification — age (epiphyseal fusion, skull sutures), sex (pelvis: subpubic angle, sciatic notch; skull), stature (long bone regression formulae), race, and any ante-mortem injuries on bone (sharp/blunt/firearm marks). Superimposition and DNA from bone/teeth aid identification.

Documentation & evidence handling

• Contemporaneous notes must be taken during the autopsy (never written from memory afterwards).
• The autopsy report records facts (findings) and the opinion (cause of death) separately; opinion may be deferred ("kept pending") until viscera chemical analysis or histopathology is available.
• Chain of custody of all samples (viscera, blood, hair, bullets) must be maintained with proper labelling, sealing, and a sample seal sent separately.
• Viscera for chemical analysis typically include: stomach + contents, small intestine (proximal ~30 cm) + contents, liver (~500 g), one half of each kidney, and blood/urine. Preservative — saturated saline for routine, except blood/CSF for alcohol where sodium fluoride + potassium oxalate is used. (Formalin is not used as it interferes with chemical analysis.)

High-yield: The preservative of choice for viscera in routine poisoning cases is saturated common salt (saturated saline); for alcohol/volatile estimation use sodium fluoride (anti-glycolytic) + potassium oxalate (anticoagulant). Formalin must NOT be used for chemical-analysis viscera.

Two-doctor (board) autopsy

In sensitive cases — custodial deaths, dowry deaths, deaths in police firing, deaths of public/political significance, and re-autopsy — a panel of two or more doctors performs the autopsy, and it is often videographed as per directives (e.g., NHRC guidelines on custodial deaths). NHRC also recommends autopsy be done as per the Model Autopsy Form and videographed in all custodial deaths.

Complications & limitations

• Negative autopsy (no cause found despite complete examination) — consider vagal inhibition, electrocution, anaphylaxis, air embolism, certain poisons.
• Artefacts — post-mortem changes mistaken for ante-mortem disease (e.g., post-mortem caloricity, decomposition gas mimicking injuries, resuscitation rib fractures, heat-related pugilistic attitude and heat haematoma in burns).
• Decomposition obscuring injuries and delaying examination.
• Infection risk to the pathologist (HIV, hepatitis B/C, tuberculosis, prion disease) — universal precautions and in-situ Rokitansky technique reduce risk.

Key differentials / commonly confused points

• Cause vs Manner vs Mode of death — Cause = disease/injury (e.g., haemorrhage); Manner = how it arose (natural/accidental/suicidal/homicidal/undetermined); Mode/Mechanism = the physiological derangement (e.g., asphyxia, coma, syncope).
• Inquest vs Autopsy — inquest is the legal inquiry into the circumstances; autopsy is the medical examination of the body.
• Police vs Magistrate inquest — magistrate for custodial/dowry/firing deaths.
• Virchow vs Letulle — single organ vs en masse (the classic trap).

Recently asked / exam angle

• Which autopsy technique removes organs en masse (as a single mass)? → Letulle's method.
• Organ removal one by one is → Virchow's method.
• In-situ dissection technique → Rokitansky.
• Removal of organs as blocks/systems → Ghon's method.
• Consent of relatives is required for which autopsy? → Clinical (pathological), NOT medicolegal.
• Who can order exhumation in India? → Magistrate; no time limit.
• Why is daylight preferred for autopsy? → Artificial light alters colour perception (bruise, jaundice, CO lividity).
• Number of cavities opened in a complete medicolegal autopsy → Three (cranial, thoracic, abdominal).
• Inquest in dowry death (within 7 yrs of marriage) → by Magistrate.
• Preservative for viscera → saturated saline; for alcohol → NaF + K oxalate; never formalin.
• "Negative autopsy" definition and its causes (vagal inhibition, anaphylaxis, electrocution).

Rapid revision

1. Medicolegal autopsy: no consent of relatives needed; all 3 cavities mandatorily opened.
2. Clinical autopsy: written consent mandatory; may be limited in extent.
3. Virchow = organ by organ; Rokitansky = in situ; Letulle = en masse; Ghon = en bloc (blocks).
4. Rokitansky (in-situ) preferred in infective bodies (HIV/hepatitis/anthrax) to limit handling.
5. Letulle best preserves anatomical relationships → ideal for complex congenital cardiac/vascular cases.
6. Exhumation: only by Magistrate's order; no statutory time limit in India; take control soil samples.
7. Dowry-death inquest (woman dead within 7 yrs of marriage, suspicious) → Magistrate inquest.
8. Autopsy in daylight preferred — artificial light distorts colour (bruise/jaundice/CO).
9. Viscera preservative: saturated saline; alcohol estimation: NaF + K oxalate; never formalin.
10. Cause ≠ Manner ≠ Mode of death — keep the three distinct.
11. Negative autopsy: complete autopsy with no cause found — think vagal inhibition, anaphylaxis, electrocution, air embolism.
12. Custodial death autopsy: board of ≥2 doctors + videography (NHRC guidelines, Model Autopsy Form).