Fetal Ventricular Dilation; prelude to Dandy-Walker Syndrome and Hydrocephalus: Synopsis of Two Case Reports

Abstract

Accurate measurement of the 3^rd and 4^th ventricles is important in cases of prenatal and postnatal diagnosis of suspected cranial anomalies. Ventricular dilation occurs with excess fluid in the embryologic ventricles during brain development, we make a comparative analysis of two case reports on a 23rd-week fetus and a 10-month-old neonate. Ultrasound findings related to horns and ventricular system through transfontanelle ultrasound (excluding any > 95^th error margin and < 5^th percentile) can be utilized for a specific diagnosis of ventricular dilation. Hydrocephalus is defined as the accumulation of excessive CSF resulting in dilation of the cerebrospinal compartment in the calvaria; which can be acquired or congenital in origin. Hydrocephalus can also be seen due to obstructed flow, faulty absorption, and overproduction of CSF (in the subarachnoid space) by a choroid plexus papilloma. The diameter of the anterior horn of the RT and LT (hydrocephalic) lateral ventricles measured 15.3mm and 14.1mm respectively, far above the threshold for normal (control) neonates / RT and LT (anterior) lateral ventricles averaging 2.40mm and 2.51mm. These documented findings indicate the excellent agreement between fetal brain sonography in the diagnosis of fetal ventriculomegaly (anterior horn/ 10.4mm) and dilation (combined 40.8mm). Mean Head Circumference (MHC) for neonatal hydrocephalus was 44.2cm far above the normal average of 36.7cm. When we assessed the clinical benchmark of 10mm or (>19mm) for the neonate ventricle, it was far above the normal range (greater than > 95^th percentile value).