Multiple dilated loops

Sonography has a role in high intestinal obstruction, especially in patients with lack of air in the gastrointestinal tract whenever marked distension of the flanks and elevation of the diaphragms is observed on the plain radiograph. In such cases, sonography is useful to differentiate the presence of multiple dilated loops filled with fluid from ascites (Fig. 1.18). It is also useful in demonstrating associ-... 

Fig. 1.66a,b. Small bowel obstruction due to adhesive band, a Supine plain radiograph shows multiple dilated loops of proximal small bowel, b Erect film demonstrates multiple air-fluid levels... 

Fig. 5.19. a,b Paralytic ileus. Note the extremely dilated small bowel loops and also the colonic loops containing gas and fluid levels, c CT image shows multiple dilated loops of almost equal caliber indicative of paralytic ileus. Arrow indicates small bowel intussusception... 

Plain film shows numerous dilated loops of bowel occupying the entire abdominal cavity, including the pelvic portion, and multiple air-fluid levels in upright film (Fig. 1.19). With this degree of distension the mucosal pattern of the small bowel is effaced and it is impossible to differentiate the small bowel from the colon (Winters et al. 1992). Examination of the colon is then warranted to disclose the presence or absence of a colonic lesion. In ileal atresia, the colon is normally placed but has an abnormally small caliber, the so-called functional microcolon typical of distal small bowel obstruction (Dalla Vecchia et al. 1998) (Fig. 1.19d,e). The presence of pneumoperitoneum indicates that perforation has occurred and a colon examination is contraindicated. Intraperitoneal calcifications, indicative of meconium peritonitis, are not uncommon in ileal atresia. 

Fig. 1.19a-e. Ileal atresia, a-c Supine, lateral, and upright abdominal radiographs show multiple dilated air-filled bowel loops occupying the entire abdominal cavity, with air-fluid levels in the upright radiograph. Note in (b) the absence of air in the rectum. With this degree of distension it is impossible to differentiate the small bowel from the colon. d,e Contrast enema outlines the minute size of the colon corresponding to an unused colon... 

On a supine film changes such as dilatation with or without obstruction, calcification and displacement of normal structures can all be identified and localized. Multiple (distended) loops are indicative of distal pathology (Fig. 5.2), whereas a few (distended) loops suggest proximal intestinal pathology (Fig. 5.3). 

Fig. 1.69a,b. Paralytic ileus due to gastroenteritis, a Supine film shows generalized dilated bowel loops and distal gas. b Upright film demonstrates multiple air-fluid levels... 

Fig. 5.18a,b. Mechanical intestinal obstruction after complicated and perforated appendectomy in a girl. Note the dilated intestinal loops (a) and multiple fluid levels on lateral film (b)... 

Characteristic sonographic findings of small bowel obstruction is demonstration of dilated bowel loops with active peristalsis (Ko et al. 1993a). Multiple segments of dilated bowel loops can be readily demonstrated when the lumen is filled with fluid. The fluid may be clear or there may be air bubbles or... 

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