COLLECTIVE REVIEW

Intestinal Malrotation—Not Just the Pediatric Surgeon’s Problem

Stephanie A Kapfer, MD, Joseph F Rappold, MD, FACS

The classic description of intestinal malrotation is that rotation is unknown. Estimates in the literature range of the term infant who presents with bilious emesis. from 1 in 6,0007,8 to1in2009 of all live births. A series Upper gastrointestinal contrast study (UGI) confirms of consecutive barium enemas (BEs) performed as part the diagnosis by identifying the right-sided position of of an evaluation of a variety of abdominal complaints the duodenal–jejunal junction or evidence of a identified nonrotation in 0.2% of all patients studied.10 . Treatment consists of the Ladd procedure.1 Autopsy studies suggest that some form of malrotation Unfortunately, diagnosis and treatment of intestinal may exist in 0.5% to 1% of the population.1,4,7 malrotation may not always be so straightforward. The What is certain is the fact that a significant percentage term itself refers not to a single congenital anomaly but of individuals with intestinal malrotation enter adult- rather to a spectrum of anomalies involving the position hood with it undetected. The percentage of these pa- and peritoneal attachments of the small and large intes- tients who will ultimately present with gastrointestinal tines. Diversity of anatomic configurations, ranging symptoms attributable to malrotation remains un- from a not-quite-normal intestinal position, to complete known. Clearly, all abdominal surgeons, not just those nonrotation, to reversed rotation, results in a wide vari- who specialize in pediatric disorders, should be familiar ety of clinical presentations and patients. with intestinal malrotation, its clinical presentation, di- The first cases of malrotation were reported in the agnosis, and treatment. literature in the mid-1700s.2,3 Progress on pathogenesis of the disease was not made until normal intestinal em- CASE REPORTS bryology was described, first by Meckel in 1817 and Patient 1 4,5 then more thoroughly by Mall in 1897. Our current A 22-year-old man presented with a history and physical understanding of intestinal development is reviewed in examination suggestive of acute appendicitis, with the 6 Figure 1. In a landmark 1923 article, Dott applied the exception of pain and tenderness localizing to the right embryologic discoveries to his experiences treating pa- upper quadrant. Preoperative CT demonstrated free tients with intestinal malrotation. He described the per- fluid and a small amount of free air in the subdiaphrag- tinent embryology and anatomic variations of malrota- matic spaces and in Morison’s pouch. A thickened ap- tion, and directly correlated his clinical observations pendix with surrounding inflammation was visualized with points of aberrant or failed embryologic develop- adjacent to the right inferior liver edge (Fig. 3). Opera- ment. Figure 2 presents a pictorial summary of the most tive findings confirmed perforated appendicitis in the common patterns of malrotation. setting of a subhepatic . No significant length of Most cases of malrotation are discovered in the first ascending colon was identified, and the terminal ileum few months of life and 90% are discovered by 1 year of was fixed to the right posterior abdominal wall by retro- age. These figures do not reflect the patients who enter peritoneal attachments. The bowel was otherwise nor- adulthood undiagnosed.1,3,7 The true incidence of mal- mally rotated and fixed.

No competing interests declared. Patient 2 The views expressed in this article are those of the authors and do not reflect the official policy or position of the Department of the Navy, Department of An 80-year-old man presented with pain and tenderness Defense, or the United States government. in the left upper quadrant and laboratory evaluation Received October 1, 2003; Revised April 21, 2004; Accepted April 21, 2004. consistent with an acute abdominal infection. CT dem- From the Department of Surgery, Naval Medical Center, San Diego, CA. onstrated a mass in the left upper quadrant that appeared Correspondence address: Joseph F Rappold, MD, FACS, Department of Surgery, Naval Medical Center, 34800 Bob Wilson Dr, San Diego, CA to lie between the transverse and left colon. Further ex- 92101. email: [email protected] amination of the CT revealed a pattern of malrotation in

© 2004 by the American College of Surgeons ISSN 1072-7515/04/$30.00 Published by Elsevier Inc. 628 doi:10.1016/j.jamcollsurg.2004.04.024 Vol. 199, No. 4, October 2004 Kapfer and Rappold Intestinal Malrotation 629

Abbreviations and Acronyms BE ϭ barium enema SMA ϭ superior mesenteric artery SMVϭ superior mesenteric vein UGI ϭ upper gastrointestinal contrast study which the was located entirely in the right ; the transverse, left, and sigmoid colon were in their normal positions; and the right colon was oriented transversely across the upper abdomen (Fig. 4). Within the cecum was the mass, a markedly irregular and thick- ened area that directly abutted the left anterior ribcage. It was highly suspicious for neoplasm, although an in- flammatory process could not be excluded. The patient was taken for exploratory , during which an inflammatory mass involving the ce- cum and splenic flexure was found in the left upper quadrant.The origin of this phlegmon was a focal area of ischemic necrosis and perforation in the cecum. Other findings were consistent with the preoperative diagnosis of a mixed malrotation. Thin retroperitoneal bands at- tached the transverse colon to the right lateral abdomi- nal wall. The formed a C-loop around the head of the pancreas but did not cross midline. The remaining small bowel was found in the right lower quadrant.

Patient 3 A 24-year-old woman with a history significant only for an appendectomy at age 10, presented to an outside institution with a 6-week history of crampy upper ab- dominal pain, nausea, and associated with oral Figure 1. Normal intestinal rotation. (A) By third week of fetal intake. She denied any chronic gastrointestinal com- development, primitive gut is divisible into three regions. These plaints. Her evaluation included normal right upper regions are the foregut (FG), midgut (MG), and hindgut (HG), each quadrant ultrasonography, esophagogastroduodenal en- with their respective blood supplies—celiac artery (CA), superior doscopy, and colonoscopy. CT was suggestive of malro- mesenteric artery (SMA), and inferior mesenteric artery (IMA). Dur- ing the first stage, the rapidly growing midgut herniates through the tation, which was confirmed by UGI. She underwent umbilical oraface (UO). (B) Duodenum rotates 90 degrees counter- exploratory laparoscopy, wherein a paraduodenal hernia clockwise, posterior to the SMA. Cephalad limb elongates, forming was discovered and reduced. multiple loops, and caudad limb remains relatively straight. (C) During the second stage, midgut returns to the abdominal cavity, Two weeks postoperatively, she presented to our insti- rotating an additional 180 degrees and pushing the hindgut to the tution complaining of persistent epigastric pain, nausea, left. (D) Cecum is the last portion to return, entering anterior to the and vomiting. Her symptoms did not resolve with con- SMA. (E) During the third stage, certain sections of the intestinal undergo a physiologic fusion and resorption, resulting in servative therapy and a workup for alternative causes was retroperitonealization of the supported structures. Right colon elon- unrevealing. Repeat UGI demonstrated an enlarged gates while assuming its retroperitoneal position. Left colon and stomach and small bowel that followed a winding course duodenum are also retroperitonealized. (F) The entire process re- down the right abdomen (Fig. 5). Delayed films con- sults in a midgut with a long, oblique mesenteric base (dotted line). firmed a left-sided colon. The patient was returned to 630 Kapfer and Rappold Intestinal Malrotation J Am Coll Surg

Figure 2. Common anatomic configurations. (A) Isolated duodenal malrotation, (B) nonrotation, (C) mixed rotation, (D) reversed rotation with colon anterior to the superior mesenteric artery (SMA), (E) reversed rotation with colon posterior to the SMA, (F) hyperrotation, (G) hyperdescent, (H) inverted cecum, (I) subhepatic cecum, (J) intraperitoneal hernia. the operating room for exploratory laparotomy. Find- and proximal jejunum were straightened, and the small ings included residual hernia sac attachments and Ladd bowel mesentery was widened. bands involving the proximal small bowel and right co- lon. These attachments were divided, the duodenum DISCUSSION Clinical presentation In general, adults with malrotation present in one of three ways—with acute obstructive symptoms and signs of impending abdominal catastrophe, with chronic ab- dominal complaints that include both pain and inter- mittent obstruction, or with atypical symptoms from a common abdominal disease. Patients who present with bilious vomiting, abdomi- nal pain, fever, tachycardia, and peritoneal findings on physical examination should be suspected of having an evolving abdominal catastrophe. Confirmatory tests in- clude an elevated white blood cell count, acidosis with an elevated base deficit and lactate level, and pain that does not resolve with nasogastric tube decompression. These patients require rapid fluid resuscitation and ex- ploratory laparotomy or laparoscopy. The most com- Figure 3. CT image demonstrating a subhepatic cecum. is seen as a dilated and inflamed tubular structure located between mon finding in a patient with malrotation is midgut liver edge (L) and cecum (C). Note the free air adjacent to the liver. volvulus leading to vascular compromise and intestinal Vol. 199, No. 4, October 2004 Kapfer and Rappold Intestinal Malrotation 631

Anatomic configurations that can present in this man- ner include mixed rotation or nonrotation with inter- mittent or partial midgut volvulus, intestinal obstruc- tion secondary to Ladd bands, reversed rotation with extrinsic compression of the colon by the overlying small bowel, and IP hernias.4 Finally, patients may present with acute or chronic abdominal complaints and have a diagnosis that is com- pletely unrelated to a coincident malrotation. This group includes patients with common problems who, because of their unusual intestinal anatomy, present with uncommon symptoms. For example, appendicitis that occurs in a patient with a subhepatic cecum will localize to the right upper quadrant, and a cecal perfo- ration in a patient with nonrotation will localize to the left lower quadrant. Preoperative evaluation may need to be modified in these patients, both to reach a diagnosis and to adequately define the malrotation.

Diagnosis Infants and children with malrotation are almost exclu- sively diagnosed by UGI, with or without BE. Adults, on

Figure 4. CT images demonstrating a mixed malrotation. (A) Cecum (C) lies in the left upper quadrant between the transverse colon (TC) and left colon (LC). Location of the mass (M) is indicated. (B) Hepatic flexure (HF) and right colon (RC) are oriented transversely across the upper abdomen. . Mixed rotation and nonrotation would be the most likely anatomic configurations.4 Patients with a mobile cecum and cecal volvulus can present similarly. Patients presenting with chronic abdominal com- plaints typically describe recurrent but remitting epi- sodes of nausea, bilious vomiting, and crampy abdomi- nal pain. Associated symptoms may include intermittent diarrhea, hematochezia, constipation, , weight loss, and headache. Symptoms may have been present since childhood or they may be of more recent onset.This collection of symptoms should be considered a surgical problem rather than a functional or a psycho- Figure 5. Upper gastrointestinal contrast study demonstrating non- rotation. Stomach (G) is normally positioned, small bowel (SB) is logical problem until proved otherwise. Unfortunately, located entirely in the right abdomen, and large bowel is located in delays in diagnosis are common for most patients.11,12 the left abdomen with cecum (C) in the pelvis. 632 Kapfer and Rappold Intestinal Malrotation J Am Coll Surg the other hand, rarely undergo UGI studies at the outset ical manifestations and anatomic configurations that re- because malrotation is not a typical diagnosis considered sult from intestinal malrotation. Three general scenarios in the evaluation of abdominal pain and intestinal ob- can be anticipated: the patient with abdominal symp- struction. For this reason, adults are diagnosed using a toms from malrotation, the patient discovered to have variety of imaging modalities including UGI, BE, plain malrotation during the evaluation and treatment of an abdominal radiographs, CT scan, and ultrasonography. abdominal complaint, and the asymptomatic patient UGI combined with BE remains the gold standard for with an incidental radiologic finding of malrotation. diagnosis. UGI often reveals a duodenal–jejunal junc- Treatment must be tailored to each individual patient, to tion that fails to cross midline and is located below the his presenting complaints, and to the timing of the di- level of the duodenal bulb. BE may show malposition of agnosis. This degree of flexibility requires understanding the right colon and cecum. Because a normally rotated of the embryological events that have led to the present- duodenum can exist in the presence of a malrotated ing condition and a working knowledge of the operative cecum and because the converse can also be true, a nor- and nonoperative treatment options. mal UGI or BE in isolation cannot exclude diagnosis of Scenario 1 3,13 malrotation. Treatment of patients with symptomatic malrotation Plain abdominal radiographs are neither sensitive nor should be guided first and foremost by acuity of their specific. They may yield hints of abnormally located presentation. Patients with an acute abdomen require bowel, eg, small bowel markings predominantly on the appropriate resuscitation and prompt operative explora- right and large bowel markings predominantly on the 14 tion. If a segment of volvulized bowel is identified as left. Such radiographic findings should prompt further being dead, resection should be performed before reduc- testing. ing the volvulus. This minimizes the amount of inflam- CT scan is used increasingly in a variety of clinical matory mediators released into the general circulation. settings. In cases of malrotation, CT may reveal right- Otherwise, the volvulus should be reduced and the sided small bowel, a left-sided cecum, an inverse rela- bowel assessed for viability. Nonviable bowel should be tionship between the superior mesenteric artery (SMA) resected. If viability is in question, a second-look lapa- and the superior mesenteric vein (SMV), and the ab- rotomy should be planned. sence or hypoplasia of the uncinate process of the pan- Treatment of the underlying malrotation in cases of creas.15,16 Midgut volvulus is seen as a whirling pattern of 17 volvulus should include lysis of all abnormal bands and mesentery and bowel about the SMA. Although most adhesions, straightening of the duodenum such that it patients with malrotation will not have all of the char- descends directly into the right lower quadrant, widen- acteristics described here, identification of any one ab- ing of the small bowel mesentery by scoring its serosal normality warrants closer scrutiny and consideration of leaves, and performing an appendectomy (Fig. 6). This other diagnostic modalities. series of maneuvers is traditionally thought of as the Ultrasonography has been used as a diagnostic tool in Ladd procedure.2,20,21 Evisceration of the IP intestines can infants. Characteristic signs of midgut volvulus include aid in the identification of abnormally restrictive bands. duodenal dilation with distal tapering, fixed midline bowel, the so-called whirlpool sign (wrapping of the SMV and bowel around the SMA), and dilation of the SMV.18,19 As in CT diagnosis, the relative positions of the SMA and SMV can indicate malrotation even in the absence of volvulus. In adults, malrotation is usually an incidental finding on an ultrasound obtained for an up- per abdominal complaint. An abnormal study requires further radiologic and clinical investigation.

Management In the adult, no single management approach or opera- Figure 6. (A) Midgut volvulus. (B) Intestinal position after Ladd tive intervention can successfully treat the variety of clin- procedure. Vol. 199, No. 4, October 2004 Kapfer and Rappold Intestinal Malrotation 633

Much has been written about placement and pexy of the dure for which consent should be obtained. In children, cecum for prevention of future volvulus. There is no evi- consent is given by the parents and can be obtained dence in either the pediatric or adult literature that ce- easily during the course of operation. This is not the case copexy improves outcomes or alters the rate of periopera- for adults. For example, if, during the performance of an tive or postoperative complications.11,22-24 exploratory laparotomy through a lower midline inci- Treatment of patients with chronic abdominal com- sion, a pelvic cecum with appendicitis is discovered, is plaints thought to be from malrotation should start with the surgeon justified in extending the incision and per- an appropriate radiologic evaluation.These patients, un- forming a Ladd procedure in addition to the appendec- like those with acute symptoms, may have incomplete tomy? The safest course in this situation would be to do resolution of their presenting symptoms after operation. whatever is required to treat the immediate problem and They should be thoroughly counseled with respect to to investigate diagnosis of malrotation on an elective anticipated benefits and potential complications before basis. If malrotation subsequently gives rise to symptoms embarking on surgical correction. In the majority of or if the patient desires its correction after an appropriate cases, surgical procedure is the appropriate course of discussion of the risks and benefits, then malrotation can treatment. be treated at a later date. In cases of chronic obstruction secondary to Ladd bands, the treatment focus is lysis of all abnormal intes- Scenario 3 tinal attachments. When an intraabdominal hernia is The greatest amount of controversy in the literature sur- encountered, the hernia should be reduced, the sac re- rounds the adult patient who is discovered to have mal- sected if possible, and the hernia defect closed. In rare rotation on radiologic examination but is asymptomatic. cases of reversed rotation, adhesions between the small The potentially catastrophic event that the Ladd pro- and large intestinal can be divided and the cedure is designed to prevent is midgut volvulus with midgut rotated clockwise 360 degrees so as to create a vascular compromise. Multiple reports may be found in condition of nonrotation. In all of these circumstances, a the literature of older children and adults who experi- Ladd procedure should be completed. enced acute and unexpected midgut volvulus. Adults Use of minimally invasive surgical techniques in diag- also may develop chronic obstructive symptoms related nosis and treatment of malrotation has been described in to an undiagnosed malrotation.23,27-29 Yet, there are the literature. Laparoscopic Ladd procedures have been many patients who remain asymptomatic for their entire performed with minimal morbidity and good suc- lives. Some authors have advocated operative interven- cess.25,26 As is the case with all new laparoscopic tech- tion only in patients who are symptomatic. Wang and niques, results must consistently be equal to or better Welch30 reviewed the records of 50 patients with malro- than those obtained with open procedure. tation, their ages ranging from 13 to 86 years. Twenty- six of these patients had symptoms directly attributable Scenario 2 to malrotation and 19 required operations. The remain- Management of patients who are discovered to have ing 24 patients were asymptomatic, diagnosis of malro- malrotation during evaluation and treatment of an un- tation having been an incidental finding.30 Findlay and related complaint should be based on the primary diag- Humphreys,31 in their review of 24 cases of adult malro- nosis. If urgent operative intervention is required, treat- tation, found 5 patients who were asymptomatic and did ment of the underlying malrotation should be not undergo operation. They suggested that discussion undertaken only if it does not add undue risk to the with the patient about the condition and possible future procedure and if the patient can physiologically tolerate complications would be sufficient.31 Others have agreed the added operative time. If operation is indicated on an that operation is not justified unless abdominal com- elective basis, treatment of the underlying malrotation plaints can be directly tied to the malrotation.32,33 can be incorporated into the operative plans. In contrast, other authors have argued that any risk Malrotation that is discovered at the time of operation for midgut volvulus, regardless of how small, warrants poses an interesting dilemma with respect to consent. If operative intervention.27,34-38 Clearly, significant se- malrotation is not involved in the disease process, then quelae of malrotation can occur despite years of its treatment would be considered an additional proce- symptom-free existence, and the timing of these se- 634 Kapfer and Rappold Intestinal Malrotation J Am Coll Surg quelae cannot be accurately predicted. Additionally, not mandatory. Until easily determined and consistent cri- all asymptomatic patients are truly without symptoms. teria are developed by which the risk of volvulus can be The literature shows that many asymptomatic patients predicted, operation would seem to be the more prudent with incidental finding of malrotation, if questioned course of action for most patients. thoroughly, actually have some abdominal complaints In this article, we described a variety of clinical sce- that can be attributed to malrotation.11,12 narios involving intestinal malrotation, three of which Several authors have attempted to identify an ana- are from our own recent experience. We discussed the tomic characteristic that is both clinically and radiolog- embryologic origins of the condition, and its various ically obvious and offers some predictive value with re- clinical presentations, its diagnosis, and options for spect to volvulus. In 1993, Schey and colleagues39 treatment. Despite the fact that malrotation usually retrospectively reviewed 53 cases of pediatric and adult manifests itself during childhood, the practicing general malrotation and categorized them into 5 distinct pat- surgeon may encounter the condition while caring for terns based on relative positions of the duodenal–jejunal adults. Failure to identify intestinal malrotation or a junction and cecum. Their analysis suggested that con- midgut volvulus may result in catastrophic conse- figurations involving an abnormal position of the quences for the patient. Success in these patients is de- duodenal–jejunal junction were at highest risk for acute pendent on a well-informed surgeon, quick recognition midgut volvulus and should be surgically corrected, even of the disease process, and timely and appropriate if asymptomatic. Configurations involving malrotation treatment. of the cecum in isolation were also at risk for volvulus but with less catastrophic consequences because of the smaller vascular distribution involved. According to REFERENCES Schey and colleagues,39 these patients should not be sur- 1. Sato RR, Oldham KT. Pediatric abdomen. In: Greenfield LJ, Mulholland MW, Oldham KT, et al, eds. Surgery: scientific gically corrected unless symptomatic. principles and practice. 3rd ed. Philadelphia: Lippincott Wil- 40 In 2002, Mehall and colleagues retrospectively re- liams & Wilkins; 2001:1993–1998. viewed 201 cases of pediatric malrotation. They classi- 2. Ladd WE. Congenital obstruction of the duodenum in children. fied patients into three groups based simply on the loca- N Engl J Med 1932;206:277–283. 3. Kiesewetter WB, Smith JW. Malrotation of midgut in infancy tion of the duodenal–jejunal junction. The junction was and childhood. Arch Surg 1958;77:483–491. described as “typical” if it was located to the right of 4. Skandalakis JE, Gray SW, Ricketts R, Richardson DD. The midline, “low” if it was located to the left of midline and small intestines. In: Skandalakis JE, Gray SW, eds. Embryology for surgeons: the embryological basis for the treatment of con- below the 12th thoracic vertebrae, and “high” if it was genital anomalies. 2nd ed. Baltimore: Williams & Wilkins; located to the left of midline and above the 12th thoracic 1994:184–236. vertebrae. Operative findings of volvulus and internal 5. Touloukian RJ, Smith EI. Disorders of rotation and fixation. In: O’Neill JA, Rowe MI, Grosfeld JL, et al, eds. . hernia were more common in the typical cases as com- 5th ed. St Louis: Mosby; 1998:1199–1214. pared with the low and high cases. Operative complica- 6. Dott NM. Anomalies of intestinal rotation: their embryology tions and persistent symptoms after operation occurred and surgical aspects with report of five cases. Br J Surg 1923;11: more frequently in the low and high cases than in the 251–286. 7. Clark LA, Oldham KT. Malrotation. In: Ashcraft KW, Murphy typical cases. Given the lower risk of volvulus, higher JP, Sharp RJ, et al, eds. Pediatric surgery. 3rd ed. Philadelphia: operative morbidity, and lower success rate, the authors WB Saunders Company; 2000:425–442. concluded that consideration should be given to nonop- 8. Warner BW. Malrotation. In: Oldham KT, Colombani PM, Foglia RP,eds. Surgery of infants and children: scientific princi- erative management of asymptomatic patients with ples and practice. Philadelphia: Lippincott-Raven; 1997:1229– duodenal–jejunal junctions classified as low or high.40 1240. Management of the asymptomatic patient with mal- 9. Donnellan WL, Kimura K. Malrotation, internal hernias, con- genital bands. In: Donnellan WL, Burrington JD, Kimura K, rotation is ultimately a matter for the surgeon and pa- eds. Abdominal surgery of infancy and childhood. New York: tient to decide together. The surgeon must first deter- Harwood Academic Publishers; 1996;43:1–27. mine if the patient is truly without symptoms. Risks and 10. Kantor JL. Anomalies of the colon: their roentgen diagnosis and benefits of both nonoperative and operative approaches clinical significance. Radiology 1934;23:651–662. 11. Firor HV,Steiger E. Morbidity of rotational abnormalities of the should be discussed. Because an operation in this cir- gut beyond infancy. Clev Clin Q 1983;50:303–309. cumstance is purely prophylactic, informed consent is 12. Powell DM, Othersen HB, Smith CD. Malrotation of the in- Vol. 199, No. 4, October 2004 Kapfer and Rappold Intestinal Malrotation 635

testines in children: the effect of age on presentation and normalities without volvulus: the role of laparoscopy. J Am Coll therapy. J Pediatr Surg 1989;24:777–780. Surg 1997;185:172–176. 13. Balthazar EJ. Intestinal malrotation in adults: roentgenographic 27. Cathcart RS, Williamson B, Gregorie HB, Glasow PF. Surgical assessment with emphasis on isolated complete and partial non- treatment of midgut nonrotation in the adult patient. Surg Gy- rotations. Am J Roentgenol 1976;126:358–367. necol Obstet 1981;152:207–210. 14. Houston CS, Wittenborg MH. Roentgen evaluation of anom- 28. Fukuya T,Brown BP,Lu CC. Midgut volvulus as a complication alies of rotation and fixation of the bowel in children. Radiology of intestinal malrotation in adults. Dig Dis Sci 1993;38:438– 1965;84:1–16. 444. 15. Zissin R, Rathaus V, Oscadchy A, et al. Intestinal malrotation as 29. Dietz DW, Walsh RM, Grundfest-Broniatowski S, et al. Intes- an incidental finding on CT in adults. Abdom Imaging 1999; tinal malrotation: a rare but important cause of bowel obstruc- 24:550–555. tion in adults. Dis Colon 2002;45:1381–1386. 16. Pickhardt PJ, Bhalla S. Intestinal malrotation in adolescents and 30. Wang C, Welch CE. Anomalies of intestinal rotation in adoles- cents and adults. Surgery 1963;54:839–854. adults: spectrum of clinical and imaging features. Am J Roent- nd genol 2002;179:1429–1435. 31. Findlay GH Jr, Humphreys CW 2 . Congenital anomalies of 17. Delaney CP,Lavery IC. Malrotation of the small intestine with intestinal rotation in adults. Surg Gynecol Obstet 1956;103: volvulus. J Am Coll Surg 2001;193:103. 417–438. 18. Weinberger E, Winters WD, Liddell RM, et al. Sonographic 32. Gohl ML, DeMeester TR. Midgut nonrotation in adults: an aggressive approach. Am J Surg 1975;129:319–323. diagnosis of intestinal malrotation in infants: importance of the 33. Gilbert HW, Armstrong CP,Thompson MH. The presentation relative positions of the superior mesenteric vein and artery. of malrotation of the intestine in adults. Ann R Coll Surg Engl Am J Roentgenol 1992;159:825–828. 1990;72:239–242. 19. Yeh WC, Wang HP, Chen C, et al. Preoperative sonographic 34. Rescorla FJ, Shedd FJ, Grosfeld JL, et al. Anomalies of intestinal diagnosis of midgut malrotation with volvulus in adults: the rotation in childhood: analysis of 447 cases. Surgery 1990;108: “whirlpool” sign. J Clin Ultrasound 1999;27:279–283. 710–716. 20. Ladd WE. Surgical diseases of the alimentary tract in infants. 35. Rothstein RD, Rombeau JL. Intestinal malrotation during preg- N Engl J Med 1936;215:705–708. nancy. Obstet Gynecol 1993;81:817–819. 21. Ladd WE, Gross RE. Abdominal surgery of infancy and child- 36. Seashore JH, Touloukian RJ. Midgut volvulus: an ever present hood. Philadelphia: WB Saunders; 1941:53–70. threat. Arch Pediatr Adolesc Med 1994;148:43–46. 22. Berardi RS. Anomalies of midgut rotation in the adult. Surg 37. Maxson RT, Franklin PA, Wagner CW. Malrotation in the older Gynecol Obstet 1980;151:113–124. child: surgical management, treatment, and outcome. Am Surg 23. Rowsom JT, Sullivan SN, Girvan DP. Midgut volvulus in the 1995;61:135–138. adult: a complication of intestinal malrotation. J Clin Gastro- 38. Prasil P, Flageole H, Shaw KS, et al. Should malrotation in enterol 1987;9:212–216. children be treated differently according to age? J Pediatr Surg 24. von Flu¨e M, Herzog U, Ackermann C, et al. Acute and chronic 2000;35:756–758. presentation of intestinal nonrotation in adults. Dis Colon Rec- 39. Schey WL, Donaldson JS, Sty JR. Malrotation of bowel: variable tum 1994;37:192–198. patterns with different surgical considerations. J Pediatr Surg 25. Frantzides CT, Cziperle DJ, Soergel K, et al. Laparoscopic Ladd 1993;28:96–101. procedure and cecopexy in the treatment of malrotation beyond 40. Mehall JR, Chandler JC, Mehall RL, et al. Management of the neonatal period. Surg Laparosc Endosc 1996;6:73–75. typical and atypical intestinal malrotation. J Pediatr Surg 2002; 26. Mazziotti MV, Strasberg SM, Langer JC. Intestinal rotation ab- 37:1169–1172.

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