Multiparametric Cranial Ultrasound Evaluation of Normal Neonatal Cerebral Ventricular Dimensions to Establish Nomograms in the Eastern Indian Population: A Cross-sectional Study

Introduction: Cerebrospinal Fluid (CSF) filled ventricles and their connecting foramina make up the brain’s ventricular system. Ventricles hold around a fifth of an adult’s CSF volume, approximately 20-25 mL. Two lateral ventricles and midline third and fourth ventricles make up the ventricular system.

Aim: To study normal neonatal cerebral ventricular dimensions to develop reference ranges in the Eastern Indian population.

Materials and Methods: This was a hospital-based observational cross-sectional study carried out on 189 neonate in the Department of Radiodiagnosis in collaboration with the Department of Neonatology, IMS and SUM Hospital, Bhubaneswar, Odisha, India. Measurement of ventricular size is of prime importance in diagnosing posthaemorrhagic ventricular dilatation and evaluating the need for intervention. Authors have studied Frontal Horn Width (FHW), Thalamo-Occipital Distance (TOD), Third Ventricle Width (TVW), Ventriculo-Hemispheric Ratio (VHR) and Levene index to establish nomograms showing normal reference range. Linear regression model was used for correlation.

Results: The FHW in present study showed a linear increase in the size with a corresponding increase in the gestational age, from 1.38 mm at 33 weeks to 1.59 mm at 40 weeks of gestation with a weak positive correlation. The TOD showed negligible change with increasing gestational age, from 17.24 mm at 33 weeks to 17.17 mm at 40 weeks. The TVW study showed a slight increase in width with increasing age, from 1.20 mm at 33 weeks to 1.45 mm at 40 weeks gestation. The VHR showed a negligible change with increasing gestational age, from 0.120 at 33 weeks to 0.100 at 40 weeks. The Levene index showed a slight increase, from 10.30 at 33 weeks to 11.64 at 40 weeks of gestation.

Conclusion: Neurosonogram has valid implications for measurement of ventricular size in diagnosing pathologic ventricular dilatation and for evaluating the need for intervention. Nomograms for different parameters (FHW, TOD, TVW, VHR and Levene index) as well as corresponding reference ranges are established for normal preterm and term neonates.