The Whirlpool Sign

Ultrasound imaging of bowel obstruction in neonates

Bowel obstruction (BO) in children has a wide differential diagnosis, ranging from non-urgent conditions to surgical emergencies. Abdominal radiographs are most often used as the first imaging modality for the evaluation of obstruction. However, for some indications, ultrasound can be the primary imaging modality. Therefore, it is incumbent on radiologists to recognize the types of bowel obstruction that can be recognized with US. Key sonographic features of BO include differential dilation of bowel loops, bowel wall thickening, and free fluid. "Do Not Miss" findings that indicate need for emergent treatment include volvulus, pneumoperitoneum, and/or signs of ischemia (bowel wall thinning and/or absent perfusion). The aim of this pictorial essay is to provide guidance on the sonographic technique and findings that enable identification of BO on US. Examples of neonatal BO on US, including common and less frequently encountered etiologies, are illustrated in this pictorial essay.

Imaging Features of Neonatal Bowel Obstruction

Radiologic evaluation of neonatal bowel obstruction is challenging owing to the overlapping clinical features and imaging appearances of the most common differential diagnoses. The key to providing an appropriate differential diagnosis comes from a combination of the patient's gestational age, clinical features, and imaging findings. While assessment of radiographs can confirm bowel obstruction and indicate whether it is likely proximal or distal, additional findings at upper or lower gastrointestinal contrast study together with use of US are important in providing an appropriate differential diagnosis. The authors provide an in-depth assessment of the appearances of the most common differential diagnoses of proximal and distal neonatal bowel obstruction at abdominal radiography and upper and lower gastrointestinal contrast studies. These are divided into imaging patterns and their associated differential diagnoses on the basis of abdominal radiographic findings. These findings include esophageal atresia variants including the "single bubble," "double bubble," and "triple bubble" and distal bowel obstruction involving the small and large bowel. Entities discussed include esophageal atresia, hypertrophic pyloric stenosis, pyloric atresia, duodenal atresia, duodenal web, malrotation with midgut volvulus, jejunal atresia, ileal atresia, meconium ileus, segmental volvulus, internal hernia, colonic atresia, Hirschsprung disease, and functional immaturity of the large bowel. The authors include the advantages of abdominal US in this algorithm, particularly for hypertrophic pyloric stenosis, duodenal web, malrotation with midgut volvulus, and segmental volvulus. ©RSNA, 2023 Online supplemental material is available for this article. Quiz questions for this article are available through the Online Learning Center.

US for Evaluation of Acute Abdominal Conditions in Neonates

US is the imaging modality of choice for evaluation of a variety of abdominal conditions, and in recent years it has also become useful and promising as a bedside technique for assessment of acute abdominal conditions in neonates. Bedside US can help, complement, and sometimes replace radiographic or contrast-enhanced studies in critically ill and labile neonates who are difficult to transport to the fluoroscopy suite. Some of the features of bedside US can be applied as point-of-care US (POCUS) of the sick neonate. Some of the abdominal conditions in neonates that can be assessed and monitored with bedside US are necrotizing enterocolitis and its complications, malrotation with a midgut volvulus, segmental volvulus, meconium peritonitis, and complicated inguinal hernia. High-resolution US with the use of 15-MHz and higher-frequency probes allows characterization of the bowel anatomy and features of intestinal abnormalities in neonates in fine detail. Color Doppler US and microvascular imaging improve accuracy in the detection and characterization of bowel vascularity, which is important in the treatment and follow-up of patients with intestinal conditions. ^© RSNA, 2023 Quiz questions for this article are available through the Online Learning Center. The slide presentation from the RSNA Annual Meeting is available for this article.

Ultrasound for Midgut Malrotation and Midgut Volvulus: AJR Expert Panel Narrative Review

Midgut volvulus in association with malrotation is a pediatric surgical emergency. Prompt and accurate diagnosis is necessary to avoid bowel ischemia and necrosis, thereby reducing morbidity and mortality. Historically, the upper gastrointestinal (UGI) series has been the preferred imaging modality for the evaluation of both midgut malrotation and volvulus, although use of ultrasound (US) is increasing. In this narrative review, we describe the findings of midgut malrotation and volvulus on US, including practical tips for acquisition and interpretation; discuss the advantages and challenges of both imaging modalities; and propose a path and safeguards for possible transition to the use of US as the first-line modality for diagnosis, based on our experience in imaging children with midgut malrotation and volvulus.

Ultrasound for the diagnosis of malrotation and volvulus in children and adolescents: a systematic review and meta-analysis

CONTEXT

Despite the advantages of ultrasound (US), upper gastrointestinal contrast series (UGI) remains the first-line diagnostic modality in the diagnosis of midgut malrotation and volvulus in children.

OBJECTIVE

Evaluate the diagnostic accuracy of US in the diagnosis of malrotation with or without volvulus in children and adolescents aged 0-21 years, compared with the reference standard (diagnosis by surgery, UGI, CT, MRI, and clinical follow-up individually or as a composite).

DATA SOURCES

We searched the electronic databases Ovid-MEDLINE, Embase, Scopus, CINAHL, and the Cochrane library in October 2019 and updated on 18 August 2020.

STUDY SELECTION

Studies evaluating the diagnostic performance of US for diagnosis of midgut malrotation with or without volvulus in children (0-21 years).

DATA EXTRACTION AND SYNTHESIS

The data were extracted independently by two authors and a bivariate model was used for synthesis.

RESULTS

Meta-analysis of 17 cohort or cross-sectional studies and 2257 participants estimated a summary sensitivity of 94% (95% CI 89% to 97%) and summary specificity of 100% (95% CI 97% to 100%) (moderate certainty evidence) for the use of US for the diagnosis of malrotation with or without midgut volvulus compared with the reference standard. Subgroup analysis and meta-regression revealed better diagnostic accuracy in malrotation not complicated by volvulus, in the neonatal population and enteric fluid administration before US.

CONCLUSIONS

Moderate certainty evidence suggests excellent diagnostic accuracy and coupled with the advantages, a strong case exists for the use of abdominal US as the first-line diagnostic test for suspected midgut malrotation with or without volvulus in children and adolescents.

A comprehensive radiologic review of abdominal and pelvic torsions

The clinical manifestations of abdominal and pelvic organ torsion can often be non-specific and can affect a wide range of ages and demographic groups. Radiologists have a key role in not only establishing the diagnosis of organ torsion, but also in the assessment of potential complications. As multiple imaging modalities may be utilized in the evaluation of abdominal and pelvic pain, recognizing the various appearances of organ torsion is important to ensure early diagnosis and thereby reducing patient morbidity and mortality, particularly since abdominal and pelvic organ torsion may not be clinically suspected at the time of initial patient presentation.

Untwisting the complexity of midgut malrotation and volvulus ultrasound

Abdominal US is emerging as an alternative to the upper gastrointestinal (GI) series as the preferred diagnostic imaging test for midgut malrotation complicated by volvulus. Unlike the upper GI series, US is free from ionizing radiation, does not require oral contrast agent, and can be performed portably and at times remotely from the interpreting radiologist, expediting diagnosis. Although some institutions do not have a standardized US protocol for midgut volvulus, many routinely use US in the setting of an infant or child with acute abdominal signs or symptoms to evaluate for common conditions such as hypertrophic pyloric stenosis, intussusception, necrotizing enterocolitis and appendicitis. Because these common conditions can overlap in age and clinical presentation with midgut volvulus, the aim of this pictorial essay is to provide instruction on the technique and diagnostic findings of midgut volvulus on US to ensure confident, accurate interpretation, and prompt treatment.

Making the diagnosis of midgut volvulus: Limited abdominal ultrasound has changed our clinical practice

PURPOSE

To assess the diagnostic accuracy of limited abdominal ultrasound (US) examination for midgut volvulus (MGV) and to evaluate how clinical practice has changed in a free-standing children's hospital leading to the near obsolescence of upper GI (UGI) studies for the diagnosis of MGV.

MATERIALS AND METHODS

All patients with suspected MGV who underwent abdominal US during 2016-2017 were identified using keyword search tools in the radiology information system. Retrospective, blinded image review was performed by a certificate of added qualification (CAQ), board certified pediatric radiologist. US images were evaluated for the presence of the superior mesenteric artery (SMA) cutoff sign and twisting of the bowel and mesentery around the SMA (whirlpool sign). The results were compared with the operative reports.

RESULTS

195 US studies were performed from 2016 to 2017. The most common presentations were vomiting (44%), abdominal pain (7%), and suspected malrotation (10%) 195 US studies were reviewed, of which 16 were nondiagnostic. The remaining 179 diagnostic studies showed MGV in 14 patients. Those 14 patients were surgically explored and confirmed to have midgut volvulus. 7 of the 16 nondiagnostic US studies were further evaluated with UGI examination with 1 patient demonstrating malrotation without volvulus, which was confirmed at surgery. 2 had CT exams which were normal. 4 were followed clinically. The remaining 3 patients went to surgery, all of which did not show MGV. There were 164 negative US, none of whom went to surgery. US was diagnostic in 92% of patients and when diagnostic the positive and negative predictive values of US were 100%.

CONCLUSION

Limited abdominal US is a highly accurate examination for the diagnosis of midgut volvulus. UGI exposes patients to ionizing radiation and should be reserved for patients in whom US is nondiagnostic or inconclusive.

TYPE OF STUDY

Retrospective review.

LEVEL OF EVIDENCE

Level 3.

The role of sonography for depiction of a whirlpool sign unrelated to midgut malrotation in neonates

BACKGROUND

The sonographic whirlpool sign of volvulus due to midgut malrotation is well recognized. However, variations of the whirlpool sign may be seen in other conditions, but this observation has received little attention in the literature.

OBJECTIVE

This study presents a series of neonates with a variety of causes of congenital intestinal obstruction, all associated with a whirlpool sign (unrelated to midgut volvulus), which was correctly recognized preoperatively on sonography. We also emphasize the pivotal role of sonography in managing congenital obstruction of the intestinal tract in neonates.

MATERIALS AND METHODS

This is a retrospective analysis of clinical, imaging and surgical findings in 11 neonates with congenital intestinal obstruction associated with a whirlpool sign (unrelated to midgut volvulus) that was recognized preoperatively on sonography and in whom the cause for the whirlpool was documented at surgery.

RESULTS

Eleven neonates (eight male, three female) had clinical and radiographic evidence of intestinal obstruction in whom sonography depicted a whirlpool sign, which was recognized on the initial sonogram in nine and on a repeat sonogram in two. The whirlpool was located in the upper abdomen in only two, mid-abdomen in five and right lower quadrant in four. The whirlpool was only 1-2 cm in diameter. An upper gastrointestinal series in three neonates failed to depict the cause of obstruction. Contrast enema in three cases had findings suggesting the site of obstruction was in the ileum but none depicted the exact cause of the obstruction. At surgery, the whirlpool sign correlated with a segmental volvulus of the small intestine in eight neonates and with the coiled distal small intestine associated with apple-peel atresia in the other three.

CONCLUSION

This study illustrates neonates in whom a whirlpool sign (unrelated to midgut volvulus) was correctly recognized on sonography before surgery. Sonography proved more useful than an upper gastrointestinal series or contrast enema in depicting the exact cause of the obstruction. Pediatric radiologists must make the effort to search throughout the entire abdomen and pelvis for a small whirlpool sign on sonography, even in the absence of midgut malrotation, in neonates with congenital intestinal obstruction. Its recognition preoperatively will facilitate a rapid diagnosis and will obviate the necessity for contrast examinations of the gastrointestinal tract, which require ionizing radiation.

A Multi-institutional Case Series With Review of Point-of-Care Ultrasound to Diagnose Malrotation and Midgut Volvulus in the Pediatric Emergency Department

Point-of-care ultrasound can be used to screen for malrotation with and without volvulus in the newborn with bilious vomiting, as well as children with unexplained intermittent abdominal pain. We discuss cases where infants and children presenting to pediatric emergency departments with bilious vomiting and/or intermittent abdominal pain were initially screened for small bowel pathology with point-of-care ultrasound. Bedside findings suggestive of midgut volvulus were confirmed with radiology-performed ultrasound or upper gastrointestinal fluoroscopy. In all cases, operative findings were consistent with malrotation of the small bowel with or without evidence of midgut volvulus.

The efficiency of sonography in diagnosing volvulus in neonates with suspected intestinal malrotation

This study is to prospectively evaluate the efficiency of sonography for volvulus diagnosis in neonates with clinically suspected intestinal malrotation.A total of 83 patients with suspected intestinal malrotation who underwent detailed abdominal sonography and upper gastrointestinal contrast study were included. Malrotation was characterized by inversion of the superior mesenteric artery (SMA) and superior mesenteric vein (SMV) in sonographic examination. The "whirlpool sign" of Color Doppler Sonography was recognized as a characteristic for malrotation with volvulus. The degrees of rotation of the SMV winding around SMA were also detected by sonography. Surgery was performed in patients with sonography diagnosed malrotation.A total of 39 patients were sonographically diagnosed as malrotation which was subsequently confirmed by surgery. The sensitivity and positive predictive value of the sonographic diagnosis were both 100% (39/39). The sensitivity, specificity and accuracy of "whirlpool sign" for the detection of midgut volvulus were 95.2% (20/21), 88.9% (16/18), and 92.3% (36/39), respectively. Greater degrees of rotation (equal or greater than 720°) showed higher risk (odds ratio, 5.0; P < .01) for intestinal necrosis occurrence.Sonography is more accurate in diagnosing suspected malrotation than upper gastrointestinal contrast study. Specific sonographic "whirlpool sign" related to volvulus may be used as a potential indicator for intestinal necrosis. In addition, sonography can exclude malrotation and may help the diagnosis of other diseases, such as annular pancreas and duodenal atresia.

Point-of-Care Ultrasound in Acute Neonatal Ascites

We present a 4-week-old neonate with acute onset of bloody stools and abdominal distention. Point-of-care ultrasound performed in the emergency department allowed for rapid diagnosis of a large amount of free intra-abdominal fluid, which together with the physical findings, prompted emergent operative exploration revealing chylous ascites. Although no areas of active volvulus were identified intraoperatively, findings in the case were suggestive of small bowel volvulus and deemed as the most likely etiology for this patient's presentation. In this report, we review the relevant aspects of ultrasonography for ascites and discuss the diagnosis of chylous ascites.

Role of upper gastrointestinal contrast studies for suspected malrotation in neonatal population

AIM

Upper gastrointestinal (UGI) contrast study is the preferred radiological investigation to diagnose malrotation of intestine. We aimed to review the role of UGI contrast in neonates (term and preterm) who were clinically suspected to have malrotation.

METHODS

The study included a retrospective review of medical charts and radiology reports.

RESULTS

A total of 164 newborn infants underwent UGI contrast study to rule out malrotation during the study period (2006-2015). Median gestational age at the time of presentation was 38 weeks (interquartile range: 35.5-39.6 weeks). Median age for clinical presentation was day 2 of life (interquartile range: 2-5 days). Out of the 164 contrast studies, 112 were normal, whereas 52 were reported to have malrotation. Of those 52 infants, 47 were confirmed to have malrotation on surgery (positive predictive value: 90). Of the 112 infants with normal UGI contrasts, nine infants underwent laparotomy for ongoing clinical symptoms out of which four infants were diagnosed to have malrotation on laparotomy. There were 22 infants born at gestational age <32 weeks, who underwent UGI contrast studies to rule out malrotation. Their clinical symptoms were similar to necrotising enterocolitis. Of 22 preterm contrast studies, six were reported to have malrotation; of these, five had surgically confirmed malrotation. No complications related to the contrast study were noted in both term and preterm infants.

CONCLUSION

Current study reaffirms the role of UGI contrast study as the investigation of choice for diagnosis of malrotation, in both term and preterm infants. UGI contrast is safe and well tolerated even in preterm infants.

Intestinal malrotation and midgut volvulus

A four-day-old boy presented with persistent bilious vomiting, bloody stained stool, and mild abdominal distension. Transabdominal ultrasound demonstrated a round soft-tissue mass-like structure in the right upper quadrant. With color Doppler ultrasound, the whirlpool sign was observed. Abdominal radiograph showed nonspecific findings. Upper gastrointestinal series revealed upper gastrointestinal tract obstruction at the level of distal duodenum. The diagnosis of intestinal malrotation with midgut volvulus was established and the treated surgically. Intestinal malrotation is congenital abnormal positioning of the bowel loops within the peritoneal cavity resulting in abnormal shortening of mesenteric root that is predisposed to midgut volvulus. Neonates and infants with persistent bilious vomiting should undergo diagnostic workup and preferably ultrasound as the first step. With classic sonographic appearance of whirlpool sign, even further imaging investigations is often not needed, and the surgeon should be alerted to plan surgery.

Usefulness of Sonography in Evaluating Children Suspected of Malrotation: Comparison With an Upper Gastrointestinal Contrast Study

OBJECTIVES

The purpose of this study was to prospectively evaluate the value of sonography in working up or ruling out malrotation by 3 sonographic features (inversion of the superior mesenteric artery and superior mesenteric vein, the whirlpool sign, and an intraperitoneal transverse duodenum) and comparing it with an upper gastrointestinal (GI) contrast study.

METHODS

A total of 70 pediatric patients who underwent detailed abdominal sonography to rule out intestinal malrotation were included. Twenty-three of them also underwent an upper GI contrast study. Surgery or clinical follow-up was taken as the reference standard. Statistical analysis was performed with the χ(2) test.

RESULTS

Twenty-three patients had a diagnosis of malrotation by surgical findings. With the combination of all 3 sonographic features, the sensitivity, specificity, and accuracy of sonography for determining malrotation were 100% (23 of 23), 97.8% (46 of 47), and 98.6% (69 of 70), respectively, whereas the sensitivity, specificity, and accuracy of the upper GI study were 40% (4 of 10), 64.3% (9 of 14), and 56.5% (13 of 23; P < .001). Combined anomalies in 2 patients and complications in 2 patients were also detected by sonography.

CONCLUSIONS

By combining inversion of the superior mesenteric artery and superior mesenteric vein, the whirlpool sign, and an intraperitoneal transverse duodenum, sonography might be more valuable for accurately working up or ruling out pediatric malrotation than an upper GI contrast study. In addition, sonography could provide extra information, such as combined anomalies and intestinal necrosis, to help management.

Sonography of the pediatric gastrointestinal system

Sonography is a commonly used modality for the investigation of abdominal symptoms in the pediatric population. It is a highly sensitive, readily available imaging modality that does not require ionizing radiation, iodinated contrast material, or anesthesia and can be performed at the bedside if necessary. Abdominal ultrasound is therefore often the first examination performed. This article presents an overview of the ultrasound characteristics of some of the most frequently encountered pathologies as well as some more rarely encountered entities. Our aim was to present a series of characteristic images of a wide gamut of pediatric abdominal conditions. The goal was to familiarize the reader with key sonographic features of both congenital and acquired gastrointestinal pathologies in children, making them more easily recognizable.

Ultrasonographic diagnosis of midgut volvulus with malrotation in children

OBJECTIVES

Midgut volvulus with malrotation is typical in newborns. We present our experience to emphasize the importance of suspecting midgut volvulus as a cause of abdominal pain also beyond infancy, particularly in relation to malrotation, and the relevance of ultrasonographic (US) signs in its diagnosis.

METHODS

A total of 34 patients (10 boys, 24 girls; ages between 1 day and 12 years) diagnosed as having malrotation or malrotation with volvulus, surgically confirmed, between 2006 and 2013 were retrospectively selected among all of the patients referred to our institution for acute abdomen and bilious vomiting. All of them underwent US and color Doppler examination before surgery. The US examinations were performed with 6 to 10 MHz microconvex and 7.5 to 10 Mhz linear transducer. The transducer was placed under xiphoid, and, with axial projection, the presence of anatomic position reversed between superior mesenteric vein (SMV) and superior mesenteric artery (SMA), as a sign of malrotation, and the presence of "whirlpool sign" (WS) (wrapping of the SMV and the mesentery around the SMA), as a sign of midgut volvulus, were evaluated.

RESULTS

In 27 of these 34 patients, midgut volvulus was present; 7 patients had intestinal malrotation. In 2 of 7 (28%) patients with malrotation, SMA and SMV were inverted. Among the patients with volvulus, 2 showed reversed vessel position and 22 patients presented the WS in association with SMA/SMV inversion (22/27, 81%).

CONCLUSIONS

Midgut volvulus with malrotation can appear beyond the neonatal age group as demonstrated in our case. The WS sign is sufficiently sensitive for its diagnosis and should be routinely researched at all ages of pediatric population. Anatomic inversion between SMV and SMA seems to be not enough sensitive in isolated malrotation diagnosis.

Diagnostic accuracy of ultrasound in determining the cause of bilious vomiting in neonates

Background

Plain radiography and contrast radiologic studies are traditionally the main options in evaluating neonates presenting with bilious vomiting. While ultrasonography (US) is more available, its diagnostic accuracy is in question.

Objectives

The purpose of this study is to determine the diagnostic accuracy of US in evaluating these patients with bilious vomiting.

Patients and Methods

All neonates with bilious vomiting or bilious nasogastric tube drainage presented to a children’s hospital in a 1.5-year period were included. US were performed in all patients. The results were compared with clinical and radiological data and the final diagnosis. We used chi-square and Fisher’s exact tests for analysis.

Results

The cause of bilious vomiting for 18 of the 23 included patients was surgical. All patients labeled as surgical candidates by US ended in surgery [positive predictive value (PPV) = 100%], while only 50% of the patients with inconclusive US were operated [negative predictive value (NPV) = 50%, Confidence Interval (CI) 95%: 29%-71%]. The sensitivity and specificity of US in diagnosing intestinal atresia (n = 9) was 89% [CI 95%: (68% - 100%)] and 100%. In cases with malrotation (n = 4) and midgut volvulus (n = 2), sonographic diagnosis was in concordance with final surgical diagnosis.

Conclusion

This study suggested that in cases in which US makes a certain diagnosis, its accuracy eliminates the need for further diagnostic tests, but if it is inconclusive, further radiological contrast studies should be tried to make the final diagnosis.

Complications of congenital and developmental abnormalities of the gastrointestinal tract in adolescents and adults: evaluation with multimodality imaging

There is a wide variety of congenital anomalies that may affect the gastrointestinal tract. Most symptomatic congenital anomalies are found in newborns and infants. Such anomalies are relatively rare in adolescents and adults, and they may be difficult to identify because clinical symptoms often are nonspecific and insidious, causing them to be mistaken for other common abdominal conditions. Multimodality imaging is useful in evaluating congenital anomalies of the gastrointestinal tract in adults. The imaging features at radiography, fluoroscopy, ultrasonography, computed tomography, and magnetic resonance imaging may help identify congenital gastrointestinal anomalies such as congenital esophageal stenosis, gastric volvulus, duodenal web, annular pancreas, heterotopic pancreas, cecal volvulus, anomalies of the omphalomesenteric duct, Hirschsprung disease, and gastrointestinal duplication cyst. Familiarity with the imaging features of the various congenital anomalies of the gastrointestinal tract and their complications is important to establish the correct diagnosis and determine appropriate treatment, which is critical to avoid life-threatening complications.

Sonographic evaluation of gastrointestinal obstruction in infants: a pictorial essay

Traditionally, gastrointestinal contrast studies have been the mainstay of evaluating infantile gastrointestinal problems. Because of technological advancements, good ultrasonography (USG) machines can provide high-resolution images with graphic anatomical clarity, especially in infants and children and thus change the traditional diagnostic trends. In this article, we illustrate the USG appearances of various causes of gastrointestinal obstruction in infants and discuss the role of USG in their evaluation.

Trapped on the "whirl": diagnostic sign on emergency CT

The "whirl sign" is an uncommon finding on emergency CT. However, it is easy to overlook if not kept in mind. Its recognition is of capital importance, being most of its causes potentially lethal. Surgical treatment is also mandatory when signs of complication are found. The whirl sign is usually found associated to midgut, cecal and sigmoid volvulus, small-bowel volvulus and closed-loop obstructions, and post-surgical mesenteric windows (including retroanastomotic hernias). CT is an optimal imaging technique to depict the so-called sign and associated CT features suggesting complication (circumferential wall thickening, pneumatosis intestinalis, pneumoperitoneum, mesenteric fat stranding, free intraperitoneal fluid, mesenteric haziness). Radiologists must be able to recognize the whirl sign and seek associated findings that strongly support the diagnosis of a spectrum of entities, some of them lethal if no treatment is established.

Volvulus of a jejunal lymphatic vascular malformation presenting with bilious vomiting and the radiological appearances of malrotation

Bile-stained vomiting in infancy is abnormal. Malrotation with small bowel volvulus is probably the most worrying of possible causes because if untreated for too long, it can result in massive bowel necrosis. As a consequence, if examination or plain radiography does not suggest another cause, an upper gastrointestinal (GI) series is often performed to exclude malrotation. If the examination is normal however and symptoms settle, should investigation stop, or how far should it be pursued? Small bowel lymphatic vascular malformations in children are extremely rare but carry a risk of obstruction, volvulus, and loss of small bowel. We present a case of a 5-year-old boy referred to our unit with bilious vomiting and the radiological findings of malrotation on upper GI series. Interestingly, a previous upper GI series undertaken during the first year of life for intermittent bilious vomiting was normal. Operative findings were of a 16-cm cystic lymphatic vascular malformation of the jejunal wall causing a 360 degrees volvulus. The mesentery was derotated, and the cyst removed with the attached section of jejunum. This case highlights the need to reinvestigate patients with bilious vomiting despite a previous normal upper GI series. The case raises the issue of whether bilious vomiting, with a normal upper GI series, should be investigated further with an abdominal ultrasound scan to identify more unusual causes such as jejunal lymphatic vascular malformations.