Collapsed Small Bowel Loops On Ct Scan

Figure 5.13. Small-bowel obstruction with adhesions and ischemic stricture.

(A) Supine plain film of the abdomen shows multiple dilated small-bowel loops having the same diameter as the colon, diagnostic of an incomplete small-bowel obstruction. (B) CT scan shows a relatively collapsed loop of small bowel just distal to the dilated small bowel (both without significant oral contrast). (C) Spot film from a single-contrast small-bowel enema demonstrates acute angulation consistent with adhesions. In addition, the angulated loop is stric-tured by ischemic changes.

Figure 5.13. Small-bowel obstruction with adhesions and ischemic stricture.

(A) Supine plain film of the abdomen shows multiple dilated small-bowel loops having the same diameter as the colon, diagnostic of an incomplete small-bowel obstruction. (B) CT scan shows a relatively collapsed loop of small bowel just distal to the dilated small bowel (both without significant oral contrast). (C) Spot film from a single-contrast small-bowel enema demonstrates acute angulation consistent with adhesions. In addition, the angulated loop is stric-tured by ischemic changes.

Loops Abdomen Test

Figure 5.14. Closed-loop obstruction with a "beak" sign. CT scan at the level of the lower abdomen demonstrates multiple dilated fluid-filled loops of small bowel consistent with a small-bowel obstruction. Just to the right of midline there is an abrupt change in caliber of the small bowel, with two loops being collapsed and high in density. One of these loops comes to an angulated and abrupt end, representing the "beak" of a closed-loop obstruction. (Courtesy of D. Frager, M.D., New York City)

Figure 5.14. Closed-loop obstruction with a "beak" sign. CT scan at the level of the lower abdomen demonstrates multiple dilated fluid-filled loops of small bowel consistent with a small-bowel obstruction. Just to the right of midline there is an abrupt change in caliber of the small bowel, with two loops being collapsed and high in density. One of these loops comes to an angulated and abrupt end, representing the "beak" of a closed-loop obstruction. (Courtesy of D. Frager, M.D., New York City)

detect the presence of a closed-loop obstruction, and last, but certainly not least, to detect the complications of a closed-loop obstruction, strangulation, and ultimately intestinal ischemia and necrosis.

In the evaluation of the subset of small-bowel obstruction caused by adhesions, CT imaging can reach a sensitivity of 100% and a specificity of 90% [46]. Most often, the lesions themselves are not seen, and the diagnosis of adhesive small-bowel obstruction is one of exclusion. Another study of patients with suspected small-bowel obstruction showed that CT made the correct diagnosis of small-bowel obstruction in 34 of 43 patients with similar accuracy for the level and cause of the obstruction [45].

Balthazar and colleagues described multiple finding suggestive of a closed-loop obstruction [47]. These included incarcerated small bowel with a radial distribution in which the mesenteric vessels were noted to be stretched and converged on the point of torsion. There, two adjacent collapsed round or oval loops could be seen with sharp tapering and constitute the "beak" sign (Fig. 5.14). A "whirl" sign is seen when a central loop of collapsed small bowel surrounds a whirlpoollike arrangement of mesentery [46] (Fig. 5.15). The fixed position of the small-bowel loops in a closed-loop obstruction can be demonstrated by

Swirl Sign Closed Loop Obstruction

Figure 5.15. Closed-loop obstruction with a "whirl" sign. CT scan of the lower abdomen reveals marked ascites and multiple dilated loops of small bowel. A spiral configuration to the mesenteric vessels is seen in the midline representing the "whirl" of a closed-loop obstruction. (Courtesy of D. Frager, M.D., New York City)

Figure 5.15. Closed-loop obstruction with a "whirl" sign. CT scan of the lower abdomen reveals marked ascites and multiple dilated loops of small bowel. A spiral configuration to the mesenteric vessels is seen in the midline representing the "whirl" of a closed-loop obstruction. (Courtesy of D. Frager, M.D., New York City)

scanning the patient in supine and either prone or decubitus positions (Fig. 5.16).

CT criteria for strangulation include slight (but not defined) circumferential bowel wall thickening (Fig. 5.17), increased attenuation of the bowel wall (Fig. 5.17), a "target" or "halo" sign (Fig. 5.18), pneumato-sis intestinalis, and a lack of homogeneous enhancement of the bowel wall following intravenous contrast enhancement [47] (Fig. 5.18). Additional findings may include mesenteric edema (haziness of vessels) (Figs. 5.17-5.19) and hemorrhage. Mesenteric ischemia is characterized by arterial blockage, mesenteric or portal venous thrombosis, thickened

Scan Bowel Obstruction

Figure 5.16. Closed-loop obstruction. (A) Supine and (B) left lateral decubitus CT scans of the abdomen reveal multiple dilated fluid-filled loops of small bowel in a constant configuration, diagnostic of a closed-loop obstruction. Note the acute curvature of the mesenteric vessels in the decubitus scan representing their entry into the closed loop. (Courtesy of K. Cho, M.D., Newark, NJ)

Figure 5.16. Closed-loop obstruction. (A) Supine and (B) left lateral decubitus CT scans of the abdomen reveal multiple dilated fluid-filled loops of small bowel in a constant configuration, diagnostic of a closed-loop obstruction. Note the acute curvature of the mesenteric vessels in the decubitus scan representing their entry into the closed loop. (Courtesy of K. Cho, M.D., Newark, NJ)

Figure 5.17. Closed-loop obstruction. CT

scan through the pelvis shows three loops of mildly dilated small-bowel with a thickened small-bowel wall with increased attenuation. The prominent mesenteric vascularity of the middle loop is the result of arterial inflow, but no venous outflow, in a closed-loop obstruction.

Figure 5.17. Closed-loop obstruction. CT

scan through the pelvis shows three loops of mildly dilated small-bowel with a thickened small-bowel wall with increased attenuation. The prominent mesenteric vascularity of the middle loop is the result of arterial inflow, but no venous outflow, in a closed-loop obstruction.

Interloop Fluid Scan
Figure 5.18. Small-bowel obstruction with ischemic changes. CT scan reveals evidence of mesenteric ischemia with hazy mesentery and interloop fluid. The loops of small bowel show varying degrees of the "halo" sign as well as differing amounts of contrast enhancement.
Omentum Bowel Looping Meaning
Figure 5.19. Small-bowel obstruction with bowel ischemia. CT scan of the midabdomen shows a loop of small bowel with a very thickened, edematous wall and a narrow lumen. Considerable edema is noted in the adjacent omentum.
Block Intestines Scan Interloop Fluid

Figure 5.20. Small-bowel obstruction with bowel necrosis. CT scan of the abdomen demonstrates a loop of dilated small bowel in the midabdomen with pneumatosis. Directly posterior to this loop is air in the splenic vein (just anterior to the superior mesenteric artery).

Figure 5.20. Small-bowel obstruction with bowel necrosis. CT scan of the abdomen demonstrates a loop of dilated small bowel in the midabdomen with pneumatosis. Directly posterior to this loop is air in the splenic vein (just anterior to the superior mesenteric artery).

small-bowel wall (again not defined), pneumatosis intestinalis (Figs. 5.20-5.22), and portal (Fig. 5.23) and/or mesenteric venous gas [47] (Fig. 5.21).

Ha et al. have reported that multiple phenomena combine to account for the development of strangulation [48]. First is the presence of a

Bowel Obstruction Scan
Figure 5.21. Small-bowel obstruction with bowel necrosis. CT scan through the pelvis reveals multiple loops of dilated small bowel. Innumerable linear collections of air are seen from gas within mesenteric veins. Severe pneumato-sis is also seen.
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Responses

  • Sancho
    What is collapsed loop ct scan result?
    3 years ago
  • simon
    What is a collapsed bowel?
    2 years ago
  • KIDANE
    What is the meaning of small bowel loops are collapased?
    2 years ago
  • charles moody
    What is the treatment for collapsed of small bowel loops?
    2 years ago
  • risto
    What causes the small bowel to collapse?
    10 months ago
  • mikko
    Can distal small bowel loop that collased self repair?
    4 months ago

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