Headaches are common presenting complaints in EDs throughout the United States. Most are benign and should be treated symptomatically. Certain historical risk factors and physical examination findings increase the likelihood of a secondary cause of headache and warrant further investigation with neuroimaging. Gross visual field testing is a critical component of the physical examination and should not be overlooked as a potential manifestation of a neurologic deficit. This article describes a patient whose headache and unilateral vision loss prompted neuroimaging that uncovered a pilocytic astrocytoma.