Purpose: Preterm infants are at high risk for brain damage and long-term neurodevelopmental problems. Cranial ultrasonography is the main neuroimaging technique for very low birth weight infants. Ventricle size and its ratio to brain volume contribute very important information about the central nervous system of preterm babies. We calculated biparietal diameter/ventricular ratio of preterm infants using cranial ultrasonography and evaluate the relationship between this ratio and neurodevelopment.
Methods: Cranial measurements were derived using routine ultrasonographic scanning. Transverse brain length, or biparietal diameter (BPD), was considered a representation of the total brain, ventricular index (VI) and thalamo-occipital distance (TOD) length were used to represent the ventricles, and their ratio was accepted as a measure of the tissue portion of the brain. The ratio of BPD to the sum of left and right VI and TOD values was recorded as BPD/(VI+TOD) ratio.
Results: Data from a total of 482 patients were analyzed. The mean gestational age was 27.6 (24-29.6) weeks and the mean birth weight was 1010 (350-1390) g. The mean BPD/(VI+TOD) ratio was 32.90 (± 2.32). At 24 months corrected age, the patients' mean MDI score was 78.64 (± 13.29) and mean PDI score was 79.49 (± 14.31). When patients with and without NDI were compared, there were significant differences between the groups in terms of BPD/(VI+TOD) ratio, MDI, and PDI (p < 0.001, p < 0.001, p < 0.001, respectively).
Conclusion: The BPD/ventricle ratio can be calculated using two-dimensional measurements in VLBW infants and reduced BPD/ventricle ratio was associated with poor neurodevelopmental outcomes.
Trial registration: NCT02848755.
Keywords: Biparietal diameter; Cranial ultrasonography; Neurodevelopmental outcome; Preterm infant; Ventricle ratio; Very low birth weight.