Moms often ask in the group, “My baby’s MRI shows widening of the extracerebral space, will it affect development?” “Does widening of the extracerebral space affect my baby?” “Will the widening of the extracerebral space grow back on its own?” There are many other questions like these, so today we will talk to you in detail about widening of the extracerebral space. Widening of the extracerebral space is a diagnosis that is made when babies are examined with a CT or MRI (Magnetic Resonance Imaging) scan of the head, some diagnosed with hydrocephalus, and some even diagnosed with cerebral dysplasia. Some babies receive a lot of treatment because of such a diagnosis, including injections of medication, various rehabilitation treatments, and so on. The baby suffers a lot, and the family suffers mental torture and financial loss. In fact, the widening of the extracerebral space in CT or MRI films of the infant’s head is normal for babies with normal skull size. It shows gaps outside the brain because the baby’s skull grows fast and the brain tissue grows slowly. Does the presence of widened extracerebral spaces on imaging report suggest sequelae? It has been reported in the literature that the subarachnoid space in the anterior frontal and temporal lobes of infants shows a gradual widening trend from birth to 6 months of age and then gradually narrows. The maximum width of the space is 6 millimeters in the anterior frontal lobe and 9 millimeters in the anterior temporal lobe, and an abnormality is only considered if it exceeds normal values. Often in the outpatient clinic we see extracerebral gap widening diagnosed even when the normal values are not exceeded. If the result exceeds normal values, it is still necessary to identify whether it is external hydrocephalus or cerebral atrophy. External hydrocephalus belongs to the category of traffic hydrocephalus, which is also known as “infantile benign subarachnoid space enlargement”, and is a benign self-healing disease in infancy (babies under 1 year old), with mostly no sequelae; while cerebral atrophy usually has sequelae such as backwardness in mental and motor development. Therefore, after imaging abnormalities of the baby’s brain, the prognosis does vary depending on the cause of the abnormality, the size, location, nature, and severity of the lesion. However, imaging is not the primary basis for determining prognosis; ultimately, it needs to be combined with clinical neurobehavioral examination to make an objective judgment. For example, intracranial hemorrhage, subarachnoid hemorrhage, and mild hypoxic-ischemic encephalopathy below grade 2 generally have a good prognosis if there are no abnormal clinical manifestations during the dynamic follow-up process. Case sharing We have followed up some babies, including a child named Yangyang (pseudonym), who was born by cesarean section at 29 w. He suffered from hyperbilirubinemia, neonatal anemia and neonatal pneumonia during the neonatal period, etc. He had widening of the extracerebral space on cranial magnetic resonance imaging (MRI) at 3 months of age. She has been going to Bao Bao Bei Bei regularly for feeding, nursing care and guidance on exercise and intelligence training since she was 1 month old at the corrected age. She was not treated with any medication or therapeutic equipment. No abnormality was found in every neuromotor examination, and the IQ test was normal at 6 months and 17 months, and the extracerebral hiatus basically disappeared at 1 year and 2 months of age. “Widening of the extracerebral space is common in preterm infants, but many full-term babies also have widening of the extracerebral space. We followed up 50 full-term babies with widening of the extracerebral space until the age of 2. They stopped all medications or instrumental treatments and were only given early education at home, and their intellectual and motor development was completely normal at the age of 2 years. In some of these babies, the cranial magnetic resonance was reviewed and the extracerebral gap widening disappeared. Therefore, if the imaging shows extracerebral widening, but all the development of the baby is normal, there is no need to intervene in the treatment. Is cranial imaging necessary? Some parents wonder if cranial imaging is not necessary since it is done for reference only and the results are so scary. The answer is, of course, yes. Many cranial disorders can only be diagnosed with imaging. When there are high-risk factors for brain injury or neurological abnormalities, brain imaging, as a basic examination, can often provide timely and early clarification and prompt treatment. In the recovery period of the disease, imaging examination can objectively reflect the regression of brain injury.