Ultrasonic ring sign.
D000005:Abdomen / Q000033:anatomy & histology*; D000293:Adolescent; D003108:Colonic Diseases / Q000175:diagnosis; D005260:Female; D006471:Gastrointestinal Hemorrhage / Q000175:diagnosis*; D006801:Humans; D007077:Ileal Diseases / Q000175:diagnosis*; D007223:Infant; D007443:Intussusception / Q000175:diagnosis*; D014463:Ultrasonography