Case contributed by Dr Ian Bickle


Infant with macrocephaly. Abnormal tendon reflexes on examination.

Patient Data

Age: <0
Gender: Female

Macrocephalic infant, with absent cerebral hemispheres, in keeping with hydranencephaly.

Note the thalami, cerebellum and brainstem are normal.

The falx is present as is a small amount of occipital lobe cortex.

Case Discussion

Hydranencephaly - perhaps also rather unkindly termed as a 'water-bag brain' is a condition of the newborn, in which the cerebral hemispheres are essential absent, due to compromise of the anterior circulation of the brain in utero.   

A range of casues have been inferred ranging from anoxia, infection and maternal exposure to toxins - illicit and otherwise.

The supratentorial brain is replaces with fluid - hence the 'water-bag brain', although the falx cerebri remains, either completely or partially.  Some occipital lobe tissue may be present.

The thalamus and posterior fossa are typically present and normal.

The condition is almost always diagnosed on antenatal ultrasound, providing this service is offered and the mother attends. 

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Case information

rID: 25150
Published: 9th Oct 2013
Last edited: 14th Aug 2019
Inclusion in quiz mode: Included

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