Plain film diagnosis in intussusception

Reducing the time in making the diagnosis and improving workflow with point-of-care ultrasound

BACKGROUND

During the past decade, point-of-care ultrasound (POC US) has been increasingly performed in emergency medicine for a variety of indications. However, pediatric emergency physicians have been slower to understand the importance of POC US in the diagnosis of critical care cases.

OBJECTIVE

This study aimed to illustrate the usefulness of POC US in improving workflow in the emergency department (ED) with an early diagnosis in a critically ill child by a pediatric emergency attending physician.

CASE

On arrival to the ED, an early diagnosis of intussusception was made using real-time POC US by a pediatric emergency medicine attending physician well trained in pediatric US.

CONCLUSIONS

This report illustrates the impact that POC US can make during an early diagnosis of intussusception. With thorough knowledge of the US features characteristic of intussusception, its accurate diagnosis using POC US has the potential to reduce morbidity and mortality as well as improve patient flow and throughput time in the ED.

Comparison of 2-view abdominal radiographs with ultrasound in children with suspected intussusception

BACKGROUND

The clinical presentation of intussusception is variable; therefore, screening with either abdominal radiography (AXR) or abdominal ultrasound (US) is often used, although the optimal method is not known.

PURPOSE

This study aimed to compare the utility of AXR with that of the US in children with suspected intussusception.

METHODS

Retrospective cohort of children age 3 months to 3 years presenting to a pediatric emergency department (ED) between 2007 and 2009. Inclusion criteria were as follows: (1) presentation to the ED for suspected intussusception and (2) both 2-view AXR and US performed during the ED visit. An AXR was deemed negative for intussusception if air was visualized in the ascending colon on 2 views and transverse colon on the supine view; US results were obtained from the radiologist report at the time of presentation. Criterion standard measures for intussusception were contrast enema, operative report, or follow-up.

RESULTS

A total of 286 children were included, with mean (SD) age 16.1 (9.1) months; 62.2% were male, and 43.7% were African American. Intussusception was present in 61 subjects (21.3%). Abdominal radiography had sensitivity of 62.3% (95% confidence interval [CI], 50.1%-74.5%) and specificity of 86.7% (95% CI, 82.2%-91.1%), whereas US had a sensitivity of 98.4% (95% CI, 95.2%-100.0%) and specificity of 96.4% (95% CI, 94.0%-98.9%). Ultrasound had a greater negative predictive value (99.5%; 95% CI, 98.6%-100.4%) compared with AXR (89.4%; 95% CI, 85.4%-93.5%). Abdominal radiography had a greater false-positive rate (13.3% vs 3.6%) and greater false-negative rate (37.8% vs 1.6%), compared with US.

CONCLUSIONS

Ultrasound is superior to AXR as a screening method for establishing and excluding the diagnosis of intussusception. The poor test characteristics of 2-view AXR suggest that it should not be used as a primary screening method in cases of suspected intussusception.

Pediatric small bowel intussusception disease: feasibility of screening for surgery with early computed tomographic evaluation

BACKGROUND

This study investigated the feasibility of early computed tomographic (CT) evaluation and the operative results of pediatric small bowel intussusception with deteriorating ischemic or obstructive symptoms, so-called small bowel intussusception disease (SBID).

METHODS

Between 1988 and 1999, among 18 patients surgically proven SBID (conventional group), 12 mimicked ileocolic intussusception and were conventionally managed with abdominal radiography, ultrasonography, reduction enema, and eventually operation. Between 2000 and 2008, we applied a modified approach with inclusion of early CT evaluation if ultrasonography showed a target lesion suspicious for SBID (diameter </=3.0 cm and/or atypically located in the paraumbilical or left abdomen). Among 15 surgically proven SBID patients (early CT group), 13 underwent early operation after CT confirmation. The clinical, imaging, and operative findings were compared between the 2 groups.

RESULTS

There were no significant differences between the 2 groups in age, gender, clinical presentations, leukocyte count, ultrasonographic features, locations of SBID, or the presence of lead points. Most patients presented with vomiting, abdominal pain, or irritable crying. In comparison with the conventional group, early CT group patients had a significantly shorter duration between admission and surgery (31.44 +/- 30.39 vs 7.47 +/- 5.95 hours; P < .01) and a lower rate of bowel complications (44.4% vs 6.7%; P = .02).

CONCLUSION

Pediatric SBID may present with nonspecific symptoms and may mimic ileocolic intussusception leading to delayed operative intervention. Early CT evaluation of patients with suspicious SBID ultrasonographic features is effective in avoiding futile reduction enema and significantly reducing the waiting time for operative management and the resultant incidence of bowel complications.

The role of abdominal radiography in the diagnosis of intussusception when interpreted by pediatric emergency physicians

OBJECTIVE

To evaluate the sensitivity and specificity of abdominal x-rays in the diagnosis of intussusception when interpreted by pediatric emergency physicians.

STUDY DESIGN

This was a prospective experimental study. Participants were board-certified/eligible pediatric emergency physicians. They evaluated a module containing radiographs of 50 cases of intussusception and 50 controls, matched for age and sex. For each x-ray, the physicians stated whether the x-ray increased, decreased or did not affect suspicion of intussusception. The primary outcome was the percentage of cases for which physicians stated that the x-ray increased their level of suspicion (sensitivity). Secondary outcomes included the proportion of false-negative results and specificity.

RESULTS

Fourteen of 15 eligible physicians participated in the study. Overall, abdominal radiography increased the index of suspicion of intussusception in 48% of cases (sensitivity) and 21% of controls; however, in 11% of cases, the abdominal x-rays were incorrectly interpreted as being reassuring. The specificity was 21%. The radiographs were deemed equivocal for 41% of cases and 58% of controls.

CONCLUSIONS

Abdominal x-rays have a low sensitivity and specificity for diagnosing intussusception when interpreted by pediatric emergency physicians.

Radiographic evaluation of intussusception: utility of left-side-down decubitus view

PURPOSE

To assess the incremental value of the left-side-down decubitus view in radiographic evaluation of ileocolic intussusception.

MATERIALS AND METHODS

The institutional review board approved this retrospective investigation with waiver of informed consent. Between February 24, 2002, and January 25, 2007, 304 studies (300 patients; mean age, 1.3 years; range, 0.1-3.9 years) met the following inclusion criteria: kidney ureter bladder (KUB) and decubitus views obtained, with subsequent proof of diagnosis. Using a consensus approach, two pediatric radiologists evaluated KUB and decubitus views for four variables: (a) discrete mass and (b) small-bowel obstruction (positive criteria); (c) air or stool in ascending colon and (d) cecal air or stool (negative criteria). On the basis of these criteria, each study was graded as negative, positive, or indeterminate for intussusception. Diagnostically determinate studies and the ability to visualize or exclude intussusception were calculated to determine sensitivity and specificity. The difference between proportions was calculated, along with 95% confidence intervals. Agreement between the supine KUB view and supine KUB plus left-side-down decubitus views was tested with the McNemar test.

RESULTS

Intussusception was present in 58 of 304 studies (19%). Adding the decubitus view to the KUB view increased the number of determinate studies from 110 of 304 (36.2%) to 205 of 304 (67.4%) (difference, 31.2 percentage points; P < .001). Intussusception was correctly identified with KUB view alone in 35 of 58 studies (60.3%); this value increased to 43 of 58 (74.1%) with KUB plus decubitus views (P = .0215). Intussusception was correctly excluded with the KUB view alone in 63 of 246 studies (25.6%); this increased to 143 of 246 studies (58.1%) with addition of the decubitus view (P < .0001).

CONCLUSION

The addition of decubitus views increased the number of diagnostically determinate studies and increased the ability to diagnose or exclude intussusception. The authors believe that a left-side-down decubitus view should be included in the initial evaluation of patients suspected of having intussusception, particularly when the supine view is diagnostically indeterminate.

Test characteristics of the 3-view abdominal radiograph series in the diagnosis of intussusception

OBJECTIVES

To determine the test characteristics of the 3-view abdominal radiograph series to exclude intussusception in children presenting to the pediatric emergency department.

METHODS

We performed a single-center retrospective review of children for whom supine, prone, and lateral decubitus abdominal radiographs were performed as part of our standard diagnostic evaluation for intussusception. A pediatric radiologist masked to the patient's clinical data and outcome reviewed all radiographs. The criterion evaluated was whether air was visualized in the ascending colon on each of the 3 radiograph views. We determined the presence or absence of intussusception hierarchically by definitive radiological study report, surgical operative note, or clinical outcome.

RESULTS

We analyzed 179 patients, of whom 27 (15.1%) were diagnosed with intussusception. The test characteristics of the 3-view radiograph series in the diagnosis of intussusception when all 3 views had air in the ascending colon were sensitivity of 100% (95% confidence interval [CI] 87-100), specificity of 18.4% (95% CI, 12.3-24.6), likelihood ratio for a negative test of 0 (95% CI, 0.01-1.53), and negative predictive value (NPV) of 100% (lower bound 95% CI, 98%). When at least 2 views had air in the ascending colon, the test characteristics were sensitivity of 96.3% (95% CI, 89.2-100), specificity of 41.4% (95% CI, 33.6-49.3), likelihood ratio for a negative test of 0.09 (0.01-0.62), and NPV of 98.4 (95% CI, 95.2-100).

CONCLUSIONS

Using specific criteria, the presence of air in the ascending colon on 2 or 3 abdominal radiograph views has the potential to substantially decrease the likelihood of or exclude intussusception.

Ultrasound evaluation of acute abdominal emergencies in infants and children

Ultrasound is extremely beneficial in the evaluation of acute pediatric abdominal disease, such as HPS, intussusception, and acute appendicitis. As techniques and equipment improve, its role in the evaluation of infants and children continues to increase.

Sonographic features of small-bowel intussusception in pediatric patients

OBJECTIVE

Small-bowel intussusception (SBI) for pediatric patients is unusual and difficult to diagnose preoperatively. This study sought to determine the sonographic findings of pediatric SBI.

METHODS

The sonographic features and surgical findings of 13 pediatric patients (7 boys, 6 girls; age range 4 months-15 years; average age 4 years and 2 months) with SBI encountered in the authors' hospital over a 12-year period were retrospectively reviewed.

RESULTS

Most of the patients presented with nonspecific symptoms, including vomiting, abdominal pain, and/or irritable crying. Sonographic screening in the emergency department revealed a doughnut or crescent-in-doughnut sign, or a multiple-concentric-rings sign for 11 of the 13 patients, and the lesions appeared short. Eight lesions were found in the paraumbilical or left abdominal regions. Sonographic measurement of the size of the lesions from these 11 patients ranged from 2 cm to 3.7 cm (average 2.77 cm). Subsequent barium enemas were performed for these 11 patients, none of which revealed colon lesions. Surgery revealed ileoileal intussusceptions for eight cases, jejunoileal for three, and jejunojejunal for the remaining two. Bowel ischemia or necrosis and pathologic lead points were demonstrated for seven and six patients, respectively, although none were recognized preoperatively.

CONCLUSIONS

Small-bowel intussusception is often over-looked due to nonspecific clinical presentations. Sonographic demonstration of a 2-3-cm sized, short, doughnut-like lesion, especially in the left abdomen or paraumbilical regions, should lead to strong suspicion of SBI.

Frequency of right lower quadrant position of the sigmoid colon in infants and young children

PURPOSE

To evaluate the frequency of right lower quadrant positioning of the sigmoid colon in infants and young children.

MATERIALS AND METHODS

Findings in 169 patients who underwent enema examination were retrospectively reviewed. Sigmoid colon position was categorized as in the left or right lower quadrant or midline. Patients who had an anatomic abnormality that affected colonic position (eg, malrotation or abdominal mass) or had previously undergone abdominal surgery were excluded. The frequency of right lower quadrant sigmoid position was evaluated for a relationship with patient age (analysis of variance) and sex (chi(2) test).

RESULTS

Patient ages were 1 day to 5 years (mean age, 13 months). The sigmoid colon was in the right lower quadrant in 74 (44%), in the left lower quadrant in 73 (43%), and in the midline in 18 (11%). The position was variable in one patient and indeterminate in three. When the sigmoid colon was within the right lower quadrant, it often extended laterally, overlying the position of the cecum and ascending colon. There were no significant correlations between right lower quadrant position and patient age (P =.262) and sex (P =.162).

CONCLUSION

In children, the sigmoid colon is often within the right lower quadrant. Knowledge of this high frequency should reduce the likelihood of misinterpreting air within a redundant right-sided sigmoid colon as air within the cecum in children suspected of having abnormalities such as intussusception.

Intussusception in children: current concepts in diagnosis and enema reduction

Intussusception cannot be reliably ruled out with clinical examination and plain radiography. However, a contrast material enema study and ultrasonography (US) allow definitive diagnosis of intussusception. The components of an intussusception produce characteristic appearances on US scans. These appearances include the multiple concentric ring sign and crescent-in-doughnut sign on axial scans and the sandwich sign and hayfork sign on longitudinal scans. Indicators of ischemia and irreducibility are trapped fluid at US and absence of blood flow at Doppler imaging. The aim of enema therapy is to reduce the greatest number of intussusceptions without producing perforation. Barium, water-soluble contrast media, water, electrolyte solutions, or air may be used with radiographic or US guidance. The differences in reduction and perforation rates between the various types of enemas are probably due more to perforations that occurred before enema therapy and the pressure exerted within the colon than to the contrast material used. The pressure within the colon is more constant with hydrostatic reduction than with air reduction; this fact may explain the lower risk of perforation with hydrostatic reduction. Radiation exposure is lower with air enema therapy than with barium enema therapy and is absent in US-guided enema therapy.