Fetal autopsy
Revision as of 17:45, 28 April 2012 by Michael (talk | contribs) (→Amnion rupture sequence: +images)
The fetal autopsy is done to determine the cause of death in a fetus. An introduction to the autopsy is in the autopsy article.
External exam
Post-mortem changes
Sequences of changes with intrauterine death:[1]
- Normal ~0-12 hours.
- Skin blistering - usu. prominent on head ~12-48 hours.
- Moderate skin separation (sloughing) - usu. hands & feet ~48-72 hours
- Massive skin separation and loosing of symphysis menti (midline mandible), symphysis pubis ~72+ hours.
Common measures[2]
- Body mass (weight).
- Crown-to-heel length.
- Crown-to-rump length.
- Occipito-frontal circumference.
- Chest circumference - at nipples.
- Abdominal circumference - at umbilicus.
Routinue sections
- Rib.
- Thymus, skin, diaphragm, psoas muscle.
- Rectum, duodenum, ileocecal region, mesentery.
- Adrenal gland.
- Kidney.
- Bladder.
- Internal genitalia.
- Spleen.
- Stomach, GE junction, GD junction, pancreas.
- Liver.
- Right lung.
- Left lung.
- Heart.
- Upper airway with thyroid.
- Pituitary.
Microscopic
Adrenal gland
- Centre regresses.
Adrenal fetal fat pattern
- Can be access with oil red O staining.
The pattern of adrenal fat is informative about duration of stress prior to (intrauterine) demise:[3]
- Pattern I: scant fat/fat only close to medullary zone; acute death/no stress reaction.
- Pattern II: widespread fat; subacute death/moderate stress reaction.
- Pattern III: massive fat - fetal zone and cortex; chronic death/marked stress reaction.
Additional ref.: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1545415/pdf/archdisch00800-0007.pdf.
Kidney
- Cortex regresses.
- Nephrogenic rests.[4]
Lung
- PMNs may be seen in chorioamnionitis.
- Meconium-laden macrophages may be seen.
Thymus
- Hassall's corpuscles (thymic corpuscle).
Image:
Amniotic rupture sequence
- AKA amnion rupture sequence.
General
The term encompasses:[5]
- Amniotic band syndrome.
- Amniotic adhesion sequence.
- Limb-body wall complex
Etiology:
- Congenital.
- Thought to arise due to an amniotic tear in the first trimester.[6]
- Karyotypes are usually normal.
Gross
- Autoamputation of appendages and body wall defects +/- anomalies of internal organs.
- Fibrous bands - key feature for amniotic band syndrome.
Images:
Developmental stuff
Chiari malformations
Numbered from least severe to most severe:
- Chiari type I - tonsils herniated[7] (radiologic definition: 4-6 mm below the plane of the foramen magnum).
- Associated with: sudden death, sleep apnea, cerebellar ataxia.
- Chiari type II - often assoc. with hydrocephaly at birth.
- Chiari type III - cerebellum + brain stem herniate through foramen magnum +/- encephalocele.[8]
- Chiari type IV - cerebellar hypoplasia or no cerebellum.
Dandy-Walker syndrome
- AKA Dandy-Walker malformation (DWM).
- Prevalence: ~ 1/5000 live borns.
- Diagnosis: ultrasound.
Features:[9]
- Complete or partial agenesis of the vermis.
- Cystic dilatation of the fourth ventricle.
- Large posterior fossa.
- +/-Hydrocephalus.
- +/-Elevation of cerebellar tentorium.
DDx:
- Arachnoid cyst.
- Blake's pouch cyst - on a contiunuum with DWM.[10]
Growth parameters
Main article: Growth charts
See also
References
- ↑ Burton, Julian L.; Rutty, Guy N. (2010). The Hospital Autopsy A Manual of Fundamental Autopsy Practice (3rd ed.). Oxford University Press. pp. 191. ISBN 978-0340965146.
- ↑ Burton, Julian L.; Rutty, Guy N. (2010). The Hospital Autopsy A Manual of Fundamental Autopsy Practice (3rd ed.). Oxford University Press. pp. 196, 198. ISBN 978-0340965146.
- ↑ Becker MJ, Becker AE (September 1976). "Fat distribution in the adrenal cortex as an indication of the mode of intrauterine death". Hum. Pathol. 7 (5): 495–504. PMID 964978.
- ↑ URL: http://www.wilmstumour.com/rests.asp. Accessed on: 28 March 2011.
- ↑ URL: http://moon.ouhsc.edu/kfung/jty1/neurotest/Q11-Ans.htm. Accessed on: 26 October 2010.
- ↑ Jamsheer, A.; Materna-Kiryluk, A.; Badura-Stronka, M.; Wiśniewska, K.; Wieckowska, B.; Mejnartowicz, J.; Balcar-Boroń, A.; Borszewska-Kornacka, M. et al. (Mar 2009). "Comparative study of clinical characteristics of amniotic rupture sequence with and without body wall defect: further evidence for separation.". Birth Defects Res A Clin Mol Teratol 85 (3): 211-5. doi:10.1002/bdra.20555. PMID 19180633.
- ↑ URL: http://rarediseases.info.nih.gov/GARD/Disease.aspx?diseaseID=9230. Accessed on: 6 May 2011.
- ↑ URL: http://www.ninds.nih.gov/disorders/chiari/detail_chiari.htm. Accessed on: 6 May 2011.
- ↑ URL: http://moon.ouhsc.edu/kfung/jty1/neurotest/Q12-Ans.htm. Accessed on: 26 October 2010.
- ↑ Calabrò, F.; Arcuri, T.; Jinkins, JR. (Apr 2000). "Blake's pouch cyst: an entity within the Dandy-Walker continuum.". Neuroradiology 42 (4): 290-5. PMID 10872175.