Unusual presentations of midgut volvulus with the whirlpool sign

Factors associated with diagnostic ultrasound for midgut volvulus and relevance of the non-diagnostic examination

BACKGROUND

Few reports explore the frequency and factors associated with diagnostic ultrasound (US) for midgut volvulus.

OBJECTIVE

To evaluate predictive factors for diagnostic US for midgut volvulus and clinical outcomes of patients with non-diagnostic US.

MATERIALS AND METHODS

This retrospective study included infants imaged for midgut volvulus with US. Exams were rated as diagnostic (midgut volvulus present or absent) or non-diagnostic by a pediatric radiologist, and in cases of disagreement with the original report, an additional pediatric radiologist was the tie-breaker. For each exam, the following were recorded: age, weight, respiratory support, exam indication, sonographer experience, and gaseous dilated bowel loops on radiography. Logistic regression models with "stepwise" variable selection were used to investigate the association of diagnostic US for midgut volvulus with each of the independent variables.

RESULTS

One hundred nineteen patients were imaged. US was diagnostic in 74% (88/119) of patients. In subsets of patients presenting with bilious emesis or age <28 days, US was diagnostic in 92% (22/24) and 90% (53/59), respectively. Logistic regression suggested that symptom type (bilious vs other) was the best predictor of diagnostic US (type 3 P=0.02). Out of 26 patients with available radiographs, US was diagnostic in 92% (12/13) of patients without bowel dilation on radiographs compared to 62% (8/13) of patients with bowel dilation (P=0.16). Weight, respiratory support, and sonographer experience did not differ between groups. Two sick neonates, ages 2 days and 30 days, in whom the primary clinical concern was dropping hematocrit and sepsis, respectively, had non-diagnostic ultrasounds in the setting of bowel dilation on radiography. Both were found to have midgut volvulus at surgery and both expired.

CONCLUSION

US was most frequently diagnostic in patients with bilious emesis or age less than 28 days. Non-diagnostic US for midgut volvulus must prompt a predetermined follow-up strategy, such as an additional imaging study (e.g., upper GI series), particularly in a sick child, as non-diagnostic US may miss midgut volvulus.

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.

Ultrasound assessment of the bowel: inflammatory bowel disease and conditions beyond

Ultrasound (US) is a versatile imaging study for the evaluation of the bowel in children. US imaging of the bowel can be used as the initial examination or in follow-up for many common pediatric diseases. In this article, we highlight our bowel US technique and describe how US can depict the features of a select group of bowel pathologies relevant to pediatric practice.

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.

Early prediction of complex midgut volvulus in neonates and infants

INTRODUCTION

Prognosis of midgut volvulus in neonates and infants younger than 1 year remains poor, as diagnostic findings may not be apparent until gut infarction had occurred. To characterize factors that help to predict complex midgut volvulus early was aim of this study.

METHODS

Institutionally approved retrospective analysis of all children younger than 1 year treated for midgut volvulus at the author's center from January 2002 to December 2011. Medical history, symptoms, laboratory and radiologic findings as well as sequelae of midgut volvulus were evaluated.

RESULTS

In 10 years, 37 children fulfilled the inclusion criteria. Of these, 43% developed complications, and mortality rate was 16%. In 30% of the patients, the only clinical sign was a sudden worsening of the general condition and abdominal distension (complex 19% vs. simple 38%). In one child with simple midgut volvulus, all clinical, laboratory and radiologic signs were negative. CART analysis identified a base excess below -1.70 and preterm birth (<36 weeks) as the best discriminators of complex and simple midgut volvulus. A score >1pt (comprised of these two factors) was found in all children with complex and in 14% of simple midgut volvulus (p < 0.001). A positive score (>1pt) offers a sensitivity of 100% (81.7-100%), specificity of 85.7% (71.8-85.7%), a PPV of 84.2% (68.8-84.2%) and NPV 100% (83.8-100%).

DISCUSSION

The study shows that midgut volvulus has a substantial morbidity and mortality. Unfortunately, not all affected children get picked up by history, laboratory and imaging. However, the proposed score helps to identify subject with increased risk of complications. It has the potential to facilitate and accelerate diagnosis of complex midgut volvulus; ultimately, it might help to reduce morbidity and mortality.

Multiphasic MDCT in small bowel volvulus

OBJECTIVE

Evaluate the use of MDCT with 3D CT angiography (CTA) and CT portal venography (CTPV) reconstruction for the diagnosis of small bowel volvulus (SBV).

METHODS

Multiphasic MDCT findings in nine patients (seven males and two females, age range 2-70) with surgically proven SBV were retrospectively reviewed. Non-contrast and double phase contrast enhanced MDCT including 3D CTA and CTPV reconstruction were performed in all the patients. Two experienced abdominal radiologists evaluated the images and defined the location, direction and degree of SBV.

RESULTS

On axial MDCT images, all cases show segmental or global dilatation of small intestine. Other findings include circumferential bowel wall thickening in eight cases, halo appearance and hyperemia in seven cases, whirl sign in six cases, beak-like appearance in six cases, closed loops in six cases and ascites in one case. CTA/CTPV showed abnormal courses involving main trunks of superior mesenteric artery (SMA) and superior mesenteric vein (SMV) in seven cases, with or without distortion of their tributaries. Normal course of SMA but abnormal course of SMV was seen in the other two cases. Of all the nine cases, whirl sign was seen in six cases and barber's pole sign in five cases. Dilated SMV was observed in eight cases and abrupt termination of SMA was found in one case. Compared with surgical findings, the location, direction and degree of SBV were correctly estimated in all cases based on CTA/CTPV.

CONCLUSION

Multiphasic MDCT with CTA/CTPV reconstruction can play an important role in the diagnosis of SBV. The location, direction and degree of SBV can all be defined preoperatively using this method.

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.

CT angiographic demonstration of a mesenteric vessel "whirlpool" in intestinal malrotation and midgut volvulus: a case report

Although the color Doppler ultrasonography diagnosis of intestinal malrotation with midgut volvulus, based on the typical "whirlpool" appearance of the mesenteric vascular structures is well-defined in the peer-reviewed literature, the combination of both the angiographic illustration of these findings and the contemporary state-of-the-art imaging techniques is lacking. We report the digital subtraction angiography and multidetector computed tomography angiography findings of a 37-year-old male with intestinal malrotation.