Mild fetal ventriculomegaly

What it means

A kind of ventriculomegaly occurring in the fetal period and usually diagnosed by prenatal ultrasound. Cerebral ventriculomegaly is defined by atrial measurements 10 mm or more. Mild ventriculomegaly (MVM) is defined as measurements between 10 and 15 mm. Measurements are obtained from an axial plane at the level of the thalamic nuclei just below the standard image to measure the BPD (PMID:16100637).

A ventricular atrial diameter of more than 10 mm at 20-24 weeks of gestation has been accepted as defining ventriculomegaly because it represents at least 3 standard deviations above the mean (which is roughly 5 mm at 20-24 weeks of gestation). If the diameter is above 15 mm, the ventriculomegaly is considered to be severe. Amongst the most common causes of ventriculomegaly are impaired absorption of CSF, developmental cerebral defects, and destroyed brain tissue.

Rare diseases that can present with this3

The range is how often this sign appears among people diagnosed with each disease — it is not a probability of having any of them. Many of these signs also occur in common, non-rare conditions. A sign on this page is a conversation to have with a clinician, not a conclusion.

Part of the broader category

Also called: Mild foetal ventriculomegaly