Patients present to the ED with visual disturbances that may be painful or painless and may include loss of visual acuity, field cuts, diplopia, and headache. A detailed history and complete ocular examination are essential to obtaining the correct diagnosis and offering expedited treatment and referral. This review discusses the differential diagnosis for patients experiencing abnormal vision from a nontraumatic or minimally traumatic etiology, and reviews diagnostic and treatment strategies from an evidence-based perspective, including point-of-care ocular ultrasound. Management of the needs of special populations, such as patients with sickle cell disease, HIV, and those with a ventriculo-peritoneal shunt, is reviewed.