Ultrasound imaging as the first line of investigation to diagnose intestinal malrotation in children: Safety and efficacy

High risk and low incidence diseases: Pediatric digestive volvulus

INTRODUCTION

Pediatric digestive volvulus is a serious condition that carries with it a high rate of morbidity and mortality.

OBJECTIVE

This review highlights the pearls and pitfalls of pediatric digestive volvulus, including the presentation, diagnosis, and management in the emergency department (ED) based on current evidence.

DISCUSSION

Pediatric digestive volvulus is a deadly condition most commonly associated with malrotation. It occurs when the stomach or small intestine twists on itself, resulting in ischemia and potentially strangulation with necrosis and perforation. Presentation differs based on the gastrointestinal (GI) segment affected, degree of twisting, and acuity of the volvulus. Gastric volvulus most commonly presents with retching with or without nonbilious emesis and epigastric distension with pain, while midgut volvulus typically presents with bilious emesis in infants. Patients with GI necrosis and perforation may present with hemodynamic compromise and peritonitis. If suspected, emergent consultation with the pediatric surgery specialist is necessary, and if this is not available, transfer to a center with a pediatric surgeon is recommended. Imaging includes plain radiography, ultrasound, or upper GI series, while treatment includes resuscitation, administration of antibiotics, and emergent surgical decompression and detorsion of the involved segments.

CONCLUSION

An understanding of pediatric digestive volvulus and its many potential mimics can assist emergency clinicians in diagnosing and managing this deadly disease.

Diagnostic value of high-resolution ultrasound combined with multi-slice computer tomography (MSCT) for pediatric intra-abdominal hernias: a retrospective study

INTRODUCTION

To explore the diagnostic value of high-resolution ultrasound combined with multi-slice computer tomography (MSCT) for pediatric intra-abdominal hernias (IAHs), and to analyze the potential causes for missed diagnosis and misdiagnosis of IAHs in children.

METHODS

A retrospective analysis was conducted on 45 children with surgically confirmed IAHs. The diagnostic rate of IAHs by preoperative high-resolution ultrasound combined with MSCT was compared with that of intraoperative examination, and the potential causes for missed diagnosis and misdiagnosis by the combination method were analyzed.

RESULTS

Forty-five cases of pediatric IAHs were categorized into primary (25/45, 55.5%) and acquired secondary hernias (20/45, 44.5%). Among children with primary hernias, mesenteric defects were identified as the predominant subtype (40%). Acquired secondary hernias typically resulted from abnormal openings in the abdominal wall or band adhesions due to trauma, surgery, or inflammation. In particular, adhesive band hernias were the major type in children with acquired secondary hernias (40%). The diagnostic rate of high-resolution ultrasound was 77.8%, with "cross sign" as a characteristic ultrasonic feature. Among 10 cases of missed diagnosis or misdiagnosis, 5 were finally diagnosed as IAHs by multi-slice computer tomography (MSCT). Overall, the diagnostic rate of pediatric IAHs by preoperative ultrasound combined with radiological imaging reached 88.9%.

DISCUSSION

IAHs in children, particularly mesenteric defects, are prone to strangulated intestinal obstruction and necrosis. High-resolution ultrasound combined with MSCT greatly enhances the diagnostic accuracy of pediatric IAHs.

Intestinal Malrotation in Children: Clinical Presentation and Outcomes

INTRODUCTION

 Intestinal malrotation (IM) is characterized by abnormal intestinal rotation and fixation predisposing to a risk of midgut volvulus. The aim of this study was to describe the clinical presentation and outcome of IM from birth through childhood.

MATERIALS AND METHODS

 This was a retrospective study of children with IM managed at a single center between 1983 and 2016. Data were retrieved from medical records and analyzed.

RESULTS

 Three hundred nineteen patients were eligible for the study. Using strict inclusion and exclusion criteria, 138 children were included. Vomiting was the most common symptom up to 5 years of age. At 6 to 15 years of age, abdominal pain was the predominant symptom. One hundred twenty-five patients underwent a Ladd's procedure and of 124 patients with available data, 20% had a postoperative complication (Clavien-Dindo IIIb-V) within 30 days. The odds ratio to develop postoperative complications was significantly increased in extremely preterm patients (p = 0.001) and in patients with severely affected intestinal circulation (p = 0.006). Two patients had intestinal failure due to midgut loss after midgut volvulus, one of whom needed intestinal transplantation. Four patients, all extremely preterm, died related to the surgical procedure. In addition, seven patients died of reasons not related to IM. Fourteen patients (11%) had adhesive bowel obstruction and one patient had recurrent midgut volvulus requiring surgical treatment.

CONCLUSIONS

 IM presents with different symptoms through childhood depending on age. Postoperative complications are common after Ladd's procedure, particularly among extremely preterm infants and patients with severely affected circulation caused by midgut volvulus.

Notable Clinical Differences Between Neonatal and Post-Neonatal Intestinal Malrotation: A Multicenter Review in Southern Japan

BACKGROUND

Most cases of intestinal malrotation appear in neonates with bilious vomiting due to midgut volvulus, whereas in cases that develop beyond infancy, the initial symptoms vary. This study investigated the clinical features of these two populations and identified issues that should be considered in daily practice.

METHODS

A retrospective chart review was conducted from January 1, 2010, to December 31, 2022. Data on patients with intestinal malrotation were collected in an anonymized fashion from five pediatric surgical hub facilities in the Southern Kyushu and Okinawa areas of Japan.

RESULTS

Of the 80 subjects, 57 (71.3%) were neonates (Group N) and 23 (28.7%) were infants and schoolchildren (Group I). The frequencies of initial symptoms, such as abdominal distention (Group N: 19.3% vs. Group I: 13.0%), bilious vomiting (59.6% vs. 43.5%), and hematochezia (8.8% vs. 21.7%), were not skewed by the age of onset (p = 0.535, 0.087, and 0.141, respectively). Midgut volvulus was significantly more frequent in Group N (71.9% [41/57] vs. 34.8% [8/23]; p = 0.005), while the degree of torsion was greater in group I (median 360° [interquartile range: 180-360°] vs. 450° [360-540°]; p = 0.029). Although the bowel resection rate was equivalent (7.0% [4/57] vs. 4.3% [1/23]; p = 1.000), half of the patients in Group N presented with 180° torsion. The neonatal intestine has been highlighted as being more susceptible to ischemia than that in older children.

CONCLUSIONS

The incidence of midgut volvulus is higher in neonates than in older children. Even relatively mild torsion can cause ischemic bowel changes during the neonatal period.

LEVEL OF EVIDENCE

LEVEL III.

Ultrasound as the first line investigation for midgut malrotation: a UK tertiary centre experience

AIM

To present the first 22-months experience of transitioning to an ultrasound-first pathway for suspected midgut malrotation.

MATERIALS AND METHODS

An "ultrasound-first" imaging pathway was initiated in October 2021. Twenty-two-months later, a search was undertaken of all <1-year-old patients with "bilious", "malrotation," or "volvulus" as the imaging indication. Reports and images from upper gastrointestinal fluoroscopy (UGI) and ultrasound were reviewed, and diagnoses and outcomes were documented.

RESULTS

The search yielded 101 eligible cases between October 2021 and July 2023. Of the patients, 63/101 (62%) had both ultrasound and UGI: 47/63 (75%) ultrasound first, 16/63 (25%) UGI first. Thirty-one per cent (31/101) had ultrasound only and 7/70 (10%) UGI only. The pathway diagnosed 7/8 (88%) infants with midgut malrotation with or without volvulus and one infant who had an inconclusive ultrasound examination with a suspected an internal hernia and who was found to have malrotation volvulus at surgery. Twenty-one infants who had confidently normal ultrasound examinations and who also had UGI all had a normal duodenojejunal flexure position. Ultrasound detected alternative pathology in eight children. Duodenal visualisation improved with time: 6/15 (40%) in the first 6 months to 23/34 (68%) after the first year.

CONCLUSION

The transition to ultrasound as the first diagnostic test for midgut malrotation can be done safely and effectively in a UK centre, which previously relied solely on UGI.

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.

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.