I Need Help Understanding My Son MRI Results. He Is

I need help understanding my son MRI results. He is 3 months old and just got diagnosed with abnormalities of the brain and a enlargement left side being bigger. How is this possible when there was nothing seen on my sonogram that was given 2 weeks prior to my c section. His results say this..... (There is diffuse cerebral volume loss with prominence of the extra axial CSF spaces. The brain parenchyma appears normal in signal. There is no restricted diffusion or intracranial susceptibility. The gray white matter differentiation is preserved. No evidence of cortical malformation or heterotopic gray matter. The ventricular system is stable in caliber and configuration. The head contour is mostly unchanged. No mass effect, midline shift, or intracranial fluid collection. The major intracranial flow voids are maintained. The imaged orbits are unremarkable. Bilateral mastoid effusion, left greater than right.) What exactly does this mean? Im really concerned.