Introduction
Background
Midgut volvulus is a condition in which the intestine has become twisted as a result of malrotation of the intestine during fetal development. Malrotation of the intestine occurs when the normal embryologic sequence of bowel development and fixation is interrupted. The malrotated bowel is prone to torsion, which can lead to midgut volvulus.
Pathophysiology
Development of the human gut takes place during the first months of fetal life. In normal embryos, physiologic herniation of the gut through the umbilicus at 6 weeks’ gestation is accompanied by a 270° counterclockwise rotation of the developing intestine around the superior mesenteric artery (SMA). By 10-12 weeks, the intestine returns to the abdomen and assumes its normal adult anatomic position. Normal small bowel mesentery has a broad attachment stretching diagonally from the duodenojejunal junction (DJJ), in the left upper quadrant, to the cecum, in the right lower quadrant. This point of attachment at the DJJ is called the ligament of Treitz.
Malrotation is most commonly caused by incomplete rotation of the intestine (<270° of counterclockwise rotation, occurring in weeks 5-12). Malrotation disorders can be divided into 3 categories:
- Nonrotation (0° to 90° of counterclockwise rotation, occurring before 6 weeks)
- Reverse rotation (abnormal rotation between 90° and 180°, causing obstruction or reversal of the normal duodenal/SMA relationship, occurring in weeks 6-10)
- Malrotation most often associated with malfixation (between 180° and 270° of counterclockwise rotation, occurring after 10 weeks)
The small bowel may be in the right abdomen; however, this finding is not reliable. Often, the large bowel is in the left abdomen.
Malrotation predisposes patients to 2 problems: midgut volvulus and small bowel obstruction.
Frequency
United States
Although malrotation is estimated to occur in 1 in 500 live births, the actual frequency of malrotation is unknown because many asymptomatic patients probably never present to a physician.
International
Incidence is the same as in the United States.
Mortality/Morbidity
- Midgut volvulus: The close proximity of the cecum to the duodenum is associated with a narrow stalk of mesentery around which the gut may twist, resulting in midgut volvulus (see Image 1). Accompanying superior mesenteric vascular compromise (first venous, followed by arterial) can lead to life-threatening ischemia of the small bowel and gangrenous necrosis. Mortality associated with midgut volvulus is at least 15%, and there is a high incidence of short gut syndrome, total parenteral nutrition dependence, and resultant cirrhosis.
- Duodenal obstruction: Coiling of the duodenum with the ascending colon produces complete or partial duodenal obstruction. Ladd bands are abnormal peritoneal reflections that cross the duodenum and pass to the undersurface of the liver or posterior abdominal wall; they cause duodenal obstruction in some patients.
Race
No racial predilection is seen.
Sex
No gender predilection is seen.
Age
In approximately 60% of patients, malrotation presents by 1 month of age. Another 20-30% of patients present at 1-12 months of age. Malrotation may remain clinically "silent" for some time and can present at any age.
Anatomy
In malrotation, the following relationships may be observed in the gut:
- The DJJ is low and to the right of the normal location (see Image 3).
- The proximal small bowel (jejunum) is in the right upper quadrant.
- The cecum is in the upper and/or left abdomen.
- The large bowel is in the left abdomen.
- Other associated anomalies are seen around the ampulla of Vater.
Presentation
In neonates, malrotation with midgut volvulus classically presents with bilious vomiting and high intestinal obstruction (see Image 2). While most neonates with bilious vomiting do not have midgut volvulus, this diagnosis must be ruled out.
Older children with malrotation may manifest a failure to thrive, chronic recurrent abdominal pain, malabsorption, or other vague presentations. The older the child is, the less readily identifiable is the clinical presentation. Nonrotation of the intestine may be asymptomatic and is an incidental finding on upper GI series performed for other reasons.
Associated anomalies are seen in approximately 60% of patients and include congenital heart disease with heterotaxy (abnormal positioning and arrangement of the abdominal organs, such as the spleen, liver, and major blood vessels; right-sided or left-sided isomerism) (see Image 7). Malrotation is almost always present in patients with congenital diaphragmatic hernia and abdominal wall defects, such as omphalocele and gastroschisis. Also, malrotation is more common with imperforate anus, duodenal atresia, duodenal web, stenosis, preduodenal portal vein, annular pancreas, and biliary atresia.
Preferred Examination
The diagnostic test of choice in a child with possible malrotation, with or without midgut volvulus, is an upper GI series.
Limitations of Techniques
In most patients with malrotation, an upper GI series is easy to perform and, in experienced hands, is easy to interpret, with the following exceptions:
- With complete duodenal obstruction, an upper GI series does not differentiate between the causes of proximal intestinal obstruction. In such cases, surgical exploration is indicated.
- A redundant duodenum, seen in some normal individuals, can be confused with malrotation. A careful following of the barium shows a normal DJJ; if uncertainty exists, barium can confirm normal rotation if the cecum is seen in the right lower quadrant.
Differential Diagnoses
Duodenal Atresia
Gastroesophageal Reflux
Hypertrophic Pyloric Stenosis
Necrotizing Enterocolitis
Other Problems to Be Considered
Malrotation without midgut volvulus
Duodenal stenosis
Duodenal web
Annular pancreas
More on Midgut Volvulus |
 Overview: Midgut Volvulus |
| Imaging: Midgut Volvulus |
| Follow-up: Midgut Volvulus |
| Multimedia: Midgut Volvulus |
| References |
| Next Page » |
References
Miyakoshi K, Ishimoto H, Tanigaki S, Minegishi K, Tanaka M, Miyazaki T. Prenatal diagnosis of midgut volvulus by sonography and magnetic resonance imaging. Am J Perinatol. Dec 2001;18(8):447-50. [Medline].
Applegate KE, Anderson JM, Klatte EC. Intestinal malrotation in children: a problem-solving approach to the upper gastrointestinal series. Radiographics. Sep-Oct 2006;26(5):1485-500. [Medline].
Filston HC, Kirks DR. Malrotation - the ubiquitous anomaly. J Pediatr Surg. Aug 1981;16(4 Suppl 1):614-20. [Medline].
Ford EG, Senac MO Jr, Srikanth MS. Malrotation of the intestine in children. Ann Surg. Feb 1992;215(2):172-8. [Medline].
Frye TR, Mah CL, Schiller M. Roentgenographic evidence of gangrenous bowel in midgut volvulus with observations in experimental volvulus. Am J Roentgenol Radium Ther Nucl Med. Feb 1972;114(2):394-401. [Medline].
Gasparini FF, Navarro OM, Dasgupta R, Gerstle JT, Thorner PS, Manson DE. Ileocolic intussusception mimicking the imaging appearance of midgut volvulus as a result of extrinsic duodenal obstruction. Pediatr Radiol. Dec 2005;35(12):1246-9. [Medline].
Hsu CY, Chiba Y, Fukui O, Sasaki Y, Miyashita S. Counterclockwise barber-pole sign on prenatal three-dimensional power Doppler sonography in a case of duodenal obstruction without intestinal malrotation. J Clin Ultrasound. Feb 2004;32(2):86-90. [Medline].
Lilien LD, Srinivasan G, Pyati SP. Green vomiting in the first 72 hours in normal infants. Am J Dis Child. Jul 1986;140(7):662-4. [Medline].
Long FR, Kramer SS, Markowitz RI. Intestinal malrotation in children: tutorial on radiographic diagnosis in difficult cases. Radiology. Mar 1996;198(3):775-80. [Medline].
Long FR, Kramer SS, Markowitz RI. Radiographic patterns of intestinal malrotation in children. Radiographics. May 1996;16(3):547-56; discussion 556-60. [Medline].
Miyakoshi K, Ishimoto H, Tanigaki S, Minegishi K, Tanaka M, Miyazaki T. Prenatal diagnosis of midgut volvulus by sonography and magnetic resonance imaging. Am J Perinatol. Dec 2001;18(8):447-50. [Medline].
Mori H, Hayashi K, Futagawa S. Vascular compromise in chronic volvulus with midgut malrotation. Pediatr Radiol. 1987;17(4):277-81. [Medline].
Powell DM, Othersen HB, Smith CD. Malrotation of the intestines in children: the effect of age on presentation and therapy. J Pediatr Surg. Aug 1989;24(8):777-80. [Medline].
Pracros JP, Sann L, Genin G. Ultrasound diagnosis of midgut volvulus: the "whirlpool" sign. Pediatr Radiol. 1992;22(1):18-20. [Medline].
Shimanuki Y, Aihara T, Takano H. Clockwise whirlpool sign at color Doppler US: an objective and definite sign of midgut volvulus. Radiology. Apr 1996;199(1):261-4. [Medline].
Simpson AJ, Leonidas JC, Krasna IH. Roentgen diagnosis of midgut malrotation: value of upper gastrointestinal radiographic study. J Pediatr Surg. Apr 1972;7(2):243-52. [Medline].
Spigland N, Brandt ML, Yazbeck S. Malrotation presenting beyond the neonatal period. J Pediatr Surg. Nov 1990;25(11):1139-42. [Medline].
Stringer DA , Babyn PS. Pediatric Gastrointestinal Imaging and Intervention. 2nd ed. Hamilton, ON, Canada: BC Decker; 2000:311-32.
Torres AM, Ziegler MM. Malrotation of the intestine. World J Surg. May-Jun 1993;17(3):326-31. [Medline].
Zerin JM, DiPietro MA. Mesenteric vascular anatomy at CT: normal and abnormal appearances. Radiology. Jun 1991;179(3):739-42. [Medline].
Zerin JM, DiPietro MA. Superior mesenteric vascular anatomy at US in patients with surgically proved malrotation of the midgut. Radiology. Jun 1992;183(3):693-4. [Medline].
Further Reading
Keywords
malrotation with midgut volvulus, nonrotation, reverse rotation, malrotation
