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Acrania-anencephaly sequence

Case contributed by Dr Praveen Jha


Antenatal scan at 14 weeks.

Patient Data

Age: 14 wks gestation pregnancy
Gender: Female

Antenatal ultrasound

There is complete absence of cranial vault with relatively disorganized brain tissue.

Case Discussion

The absence of cranial vault (acrania) with disorganized herniated brain tissue (exencephaly) are part of the acrania-exencephaly-anencephaly sequence.

The key finding is the lack of an ossified cranial vault.

Note that the posterior fossa "cyst" labeled in the images are likely reflective of abnormal brain parenchyma. 

This is usually an isolated finding but may occasionally be associated with chromosomal abnormalities.

Prognosis is universally dismal; babies born with this condition do not tend to survive longer than a few minutes after delivery.

It is important to note that once a woman has had a pregnancy with this condition, she is at markedly increased risk of neural tube defects (i.e., anencephaly, encephalocoele and meningomyelocoele) for subsequent pregnancies, and double dosage of periconceptional folic acid supplementation is recommended.

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Case information

rID: 22018
Published: 14th Nov 2015
Last edited: 28th Dec 2019
Inclusion in quiz mode: Included

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