Ultrasound grading of cerebral ventricular dilatation in preterm neonates

To compare three grading systems previously described for the measurement of cerebral ventricular dilatation in preterm neonates using ultrasound scans and then to compare these with expert clinical judgement.

Eighty-one preterm neonates <1500 g birthweight or < 32 weeks' gestation, with normal, mild, moderate or severely dilated ventricles recorded predominantly during the first 2 weeks of life were selected to ensure a broad representation of ventricular size. Their cranial ultrasound scans obtained nearest to 6 weeks of age were studied. The ventricular index, the diagonal width in the coronal plane and the ventricular height in the parasagittal plane were measured adjacent to the foramen of Monro and were used to grade the degree of dilatation. In 20 of these neonates, this grading was compared with grading based on expert clinical judgement.

Grading according to the ventricular index defined 79% of the scans as normal. However, only 44% and 39% were considered to be normal according to vertical height and diagonal width, respectively. There was a high level of correlation between expert clinical judgement and grading based on ventricular height measurement (r = 0.812; area under receiver operating characteristic (ROC) curve = 0.922) and the diagonal width (r = 0.806; area under ROC curve = 0.935). Ventricular index correlated poorly with clinical judgement (r = 0.298; area under ROC curve = 0.604).

The measurement of ventricular height and the measurement of diagonal width correlated well with expert clinical judgement. The ventricular index correlated poorly and was less sensitive to mild dilatation. There was no correlation between the ventricular index and the other two measures. The ventricular height and the diagonal width are more appropriate for assessing ventricular dilatation in preterm neonates.