CNS tumors span a wide range of clinical presentations The most critical goal is the timely identification and management of cord compression and increased ICP The goal of early identification of CNS tumors needs to be balanced against exposure to ionizing radiation from CT given that many children present with nonspecific symptoms including headache and/or vomiting Careful recognition of atypical features and/or concerning associated signs or symptoms can assist in decision making regarding advanced imaging CLINICAL PEARL AND PITFALLS Clinical clues for increased ICP may include a bulging fontanel in infants, or headache with early morning vomiting in older children Measurement of sodium levels is particularly important in patients with CNS tumors Current Evidence Brain tumors represent the most common solid tumor in the pediatric population and the second most frequent pediatric cancer overall There are approximately 2,000 new malignant brain tumors diagnosed annually in children These tumors can affect children and adolescents of any age group, but the peak incidence is in children to 10 years old Supratentorial tumors are more common in children younger than year and older than 10 years Infratentorial lesions are more common between ages of and 10 years Unlike in adults, brain tumors in children are usually primary, not metastatic Since tumor location usually drives the presenting signs and symptoms, this is the most useful categorization in the ED ( Table 98.4 ) Clinical Considerations Clinical Recognition Some of the symptoms of brain tumors in children are nonspecific, and nonlocalizing complaints occur with a variety of tumor types Examples include headache, altered behavior, vision changes, altered growth or weight, somnolence, and altered school performance The diagnosis of brain tumor may be delayed in such patients Once patients develop signs and symptoms more easily referred to the CNS, their presentations tend to hinge on the tumor location ( Table 98.4 ) Infratentorial tumors may present with cranial nerve deficits, such as facial nerve palsies, dysphagia, or paresis of cranial nerve VI, causing diplopia or strabismus Ependymomas of the fourth ventricle may present with hydrocephalus and increased ICP Cerebellar lesions can cause truncal ataxia and a reeling gait when located on the midline When only one cerebellar hemisphere is involved, patients may display