months and 18 months of age. A wide, full and firm fontanel is a sign of increased intracranial pressure. Large scalp veins on your baby’s head. This is a sign of increased blood volume in the blood vessels in their brain. A downward gaze of your child’s eyes (rather than moving or staring ahead). This is called setting-sun eye phenomenon in infancy, or sundowning in infants, and is a sign of increased pressure on their brain. Lack of weight gain. Having a poor appetite and not gaining weight, called “failure to thrive,” can sometimes be associated with a brain issue. Advertisement Imaging tests Imaging tests may include: Ultrasound . This may be the first imaging test your child’s healthcare provider orders because it’s safe (doesn’t involve radiation), quick and easy to do, and doesn’t require sedation. This imaging test can show most brain structures if your child’s brain fontanel (especially the front-of-skull fontanel) hasn’t closed. Computed tomography (CT) . This imaging test shows changes in brain tissue. Because radiation is used in CT, your child’s healthcare provider might order it if an ultrasound doesn’t provide enough information or when sedation isn’t possible. Fast magnetic resonance imaging (MRI). This special version of MRI is a quick test that doesn’t require sedation. It can reveal extra fluid in your child’s brain. What are the complications of macrocephaly? Complications include: Brainstem compression from an oversized brain not having enough room within your child’s skull. Hydrocephalus, which can lead to death if not treated quickly. Seizures and epilepsy. Developmental delays. Abnormal brain function. Management and Treatment How is macrocephaly treated? Treatment depends on the underlying cause. Benign familial macrocephaly and benign enlargement of the subarachnoid space in infancy (BESSI) If your child has no neurologic symptoms, is meeting developmental milestones and has a family history of a larger-sized head, it’s likely that head siz