A Case of Inflammatory Fibroid Polyp Causing Small-Bowel Intussusception in which Retrograde Double-Balloon Enteroscopy was Useful for the Preoperative Diagnosis - Miyata, T; Yamamoto, H; Kita, H; Yano, T; Sunada, K; Sekine, Y; Iwamoto, M; Kuno, A; Onishi, N; Ido, K; Nokubi, M; Tanaka, A; Sugano, K (Endoscopy, 2004)