Volvulus

Gastric volvulus is a rare condition encountered in the adult as well as the pediatric age group. The majority of cases are of the mesenteroaxial type rather than the or-ganoaxial type.23 Anomalies associated with acute gastric volvulus include diaphragmatic defects, intestinal malrotation, and wandering spleen.24 Most cases of gastric volvulus seem to be secondary to deficient fixation. Absence of the gastrophrenic ligament and the gastrosplenic ligament as well as an absence of the spleen may lead to

gastric volvulus in asplenic patients. Elongation or absence of the splenorenal ligament even with preservation of the gastrosplenic ligament may lead to mesenteroaxial gastric volvulus (Fig. 2-16). Gastric volvulus can be re

Fig. 2-15. Reduction of the physiologic herniation.

This is complete one week after the configuration shown in Figure 2-14. The postarterial limb has partially completed its 180° rotation. The cecum now lies in the upper abdomen on its way to the right side. CB = cecal bud. (From Javors BR, Sloves JH.4)

current, intermittent, or resolve spontaneously or by placement of a nasogastric tube.

Cecal volvulus is a rare cause of cecal distention and accounts for 11% of all intestinal volvulus.26 It develops in association with an abnormal fixation of the cecum to the posterior parietal peritoneum; a freely mobile ce-cum is a prerequisite for it. An abnormally distended cecum is demonstrated in the midabdomen on radiographs, sometimes recognizable as the coffee bean sign. Contrast enema is usually diagnostic, but a whirl sign, which is composed of the twisted portion of the cecum and mesentery, may be shown on CT (Fig. 2-17).27

Nonrotation, often called malrotation, is the most commonly encountered major anomaly of rotation. In actuality, it is incomplete rotation that stops after the first 90° 9,10,22 At this point, the prearterial limb lies in the right hemiabdomen, and the postarterial lies in the left. In addition, the order of the returning loops of midgut is reversed, with the distal limb leading the proximal. This results in the jejunum lying in the right upper abdomen, whereas the colon lies to the left of midline (Fig. 2-18). The duodenal sweep is not formed, and there may be an unusual redundancy to the duodenum on the right side of the spine. The duodenal-jejunal junction then usually lies medial to the left pedicle of the spine.28

Cecal Volvulus Reduction

Fig. 2-14. Frontal view of a 10-week fetus.

The elongated redundant prearterial limb has reentered the abdomen and crossed to the left of and behind the SMA. This displaces the hindgut to the left. Heavy lines mark the foregut-midgut (/) and the midgut-hindgut (//) junctions. CB = cecal bud; OMD = omphalomesenteric duct; UP = umbilical orifice. (From Javors BR, Sloves JH.4)

Limb Bud Rotation

Fig. 2-15. Reduction of the physiologic herniation.

This is complete one week after the configuration shown in Figure 2-14. The postarterial limb has partially completed its 180° rotation. The cecum now lies in the upper abdomen on its way to the right side. CB = cecal bud. (From Javors BR, Sloves JH.4)

b
Colonic Volvulus Nursing

Fig. 2—16. Acute gastric volvulus (mesenteroaxial type) with wandering spleen.

A 64-year-old female presented with recurrent vomiting.

(a) Supine radiograph shows a gas-filled abdominal mass (arrows).

(b) Supine barium examination shows a lower gastric fundus (F) and a high gastric antrum (A). (c and d) Two T2-weighted axial MR views and sagittal view (e) show a distended stomach containing a large amount of gas and fluid (St), a posterior location of the gastric antrum (A) between gastric fundus (F) and gastric body (B), and medially positioned spleen (Sp) along the greater curvature of the stomach. P = pancreatic tail; LK = left kidney. (Courtesy of Satoru Hosoi, M.D.)

Most of the bowel shares a common mesentery that is prone to volvulus, particularly with a short mesenteric root. Patients with malrotation in whom the cecum is found in either upper quadrant are the most prone to develop a volvulus. Midgut volvulus is usually considered a surgical emergency, generally occurring in infants during the first weeks of life. It has been recently recognized that midgut volvulus may occur in adults, and its clinical presentations may be vague and chronic or recurrent.28,29 On CT, the whirled appearance representing intestinal loops and mesenteric fat with branches of mesenteric vessels, thrombosed or patent, wrapping around the superior mesenteric artery, which may be thrombosed, calcified, or patent, can be diagnostic. Dilated collateral veins and/or congested or edematous mesentery may be present distally (Fig. 2-19). Because the proximal limb returns to the abdomen first, an abnormally rotated proximal limb does not always result in an abnormally positioned distal limb. However, an abnormally positioned distal limb is almost invariably associated with an abnormal proximal one.4 Faulty resorption of the suspending dorsal mesentery of the colon

Fluoro Small Bowel Follow Through Cecum

A 65-year-old male presented with abdominal pain and vomiting.

(a) Contrast enema shows a twisting (curved arrows) of the abnormally located cecum (C) that is markedly distended.

(b) Postcontrast CT shows a distended air-filled cecum (C) and twisted portion of cecum and mesentery (curved arrows). Emergency surgery revealed a cecal volvulus with an elongated, nonattached ascending colon and cecum.

(Courtesy of Yoshiki Senba, M.D.)

Twisted Small Intestine SurgeryReversed Rotation With Volvulus

Fig. 2-18. Midgut nonrotation.

Upper GI series with small bowel follow-through demonstrates the jejunum in the right upper quadrant and the cecum and ascending colon in the midline. These are the classic findings of midgut nonrotation.

Fig. 2-18. Midgut nonrotation.

Upper GI series with small bowel follow-through demonstrates the jejunum in the right upper quadrant and the cecum and ascending colon in the midline. These are the classic findings of midgut nonrotation.

may result in excessive mobility of the bowel (Fig. 220) and may predispose it to volvulus30 (Fig. 2-21).

Essentials of Human Physiology

Essentials of Human Physiology

This ebook provides an introductory explanation of the workings of the human body, with an effort to draw connections between the body systems and explain their interdependencies. A framework for the book is homeostasis and how the body maintains balance within each system. This is intended as a first introduction to physiology for a college-level course.

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