Correct answer to Q1 is: Vein of galen aneurysmal malformation.

Correct answer to Q2 is: Foetal heart failure caused by the cerebral vascular malformation

Additional discussion

Patients with aneurysmal malformation of the vein of Galen have an underlying arteriovenous shunting of blood in the cerebral circulation. Ultrasound assessment therefore also includes evaluation of the hemodynamic impact of the intracranial shunt. The cardiac outcome is characterized by dilatation of the right cavities (image 3). Colour Doppler may reveal tricuspid regurgitation and dilatation of the jugular vessels (image 4). These signs can occur early, sometimes as early as the second trimester, and are pathognomonic of intracranial arteriovenous fistula (5).

Other signs of right heart failure, such as hepatomegaly, serous intraperitoneal effusion (image 5) and hydramnios, are more rare and appear later. The final stage is fetoplacental hydrops (6).

Conclusion

Vein of Galen aneurysm is a rare, intracranial, vascular, congenital malformation. We report an antenatal diagnosis by ultrasound at 26 weeks gestation. The neonatal prognosis is poor if fetal cardiac insufficiency or cerebral lesions (hydrocephaly, porencephaly, intracerebral hemorrhage) are present antenatally.

Conflicts of Interest:

“The authors declare no conflict of interest.”

References

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