Case report
A 35-year-old pregnant woman (no consanguinity) was referred for mild bilateral ventriculomegaly at 35 weeks of pregnancy. The first and second trimester US exams were normal.
Our US and MRI examination revealed the following findings:
- A small 7mm cyst at the location of foramen of Monro as a causative lesion, suggestive of colloid cyst.
- Lateral ventricle diameters were about 12.5 mm.
- The corpus callosum (CC) length was slightly less than 5th percentile. No other abnormality was detected.
In the US exam the cyst was clearly identified. The posterior part and splenium of CC were not formed well which was compatible with partial agenesis.
The baby was born at 38 weeks. She underwent F/U and now is about 10 months. She is asymptomatic and without obvious problem. The prenatal diagnosis of colloid cyst was postnatally confirmed.
Image 1; videos 1, 2 and 3: 2D image shows the posterior part and splenium of corpus callosum were not formed well which was compatible with partial agenesis. Videos clearly show colloid cyst at foramen of Monro and mild bilateral ventriculomegaly.