Because cecum does not contain fluid and terminal ileum is collapsed in Fig.10-Fig.12, distended small intestine indicates mechanical obstruction. A large quantity of ascites in Fig.1 (reference mark), distended small bowel is gasless,ascites between mesentery or mesenteric stranding (Fig.6 and Fig.7: black arrowheads), these 3 findings and pneumatosis (white arrowheads of Fig.8 - Fig.12) strongly suggest strangulated obstruction with necrosis or ischemia. Because confirmation of closed loop formation leads to definite diagnosis, start tracking down from 1 and A of Fig.18. 1 arrives at obstruction point of 58 and A at F of Fig.13. Ti of Fig.10-Fig.12 is terminal ileum indicating that the point of strangulation is about 15cm from cecum. a of Fig.14-d of Fig.17, circle number 1-7 and black arrow show simple obstruction of oral site. Surgery revealed necrotic ileum of about 100cm length at 10cm from cecum by an adhesive band (Fig.A: black arrow). It is the case of strangulated bowel obstruction which occurred 41 years after appendectomy.