Comparison of Brain Volumes Measured by 2D USG and MRI

All preterm infants less than 32 weeks of gestational age undergo cranial USG examination routinely at least, in the first week of life, at the end of first month and corrected age 36 weeks and 40 weeks. We will performa all USG mesurements with measureing intracranial hegiht, anteroposterior diameter, biparietal diamater, ventriccular height, thalamo-occipital distance and ventricular index. We will calculate the brain volume as a spheric geometric shape than we will calculate two ventricles as conical shapes. Absolute brain volume will be calculating by substracting two ventricles from total brain volume. At 40 weeks of age we will perform a cranial MRI to show exact brain volume and we will ccompare two different methods.