Performance of overnight on-call radiology residents in interpreting unenhanced abdominopelvic magnetic resonance imaging studies performed for pediatric right lower quadrant abdominal pain.

BACKGROUND: Abdominopelvic magnetic resonance imaging (MRI) is increasingly being used to evaluate children with abdominal pain suspected of having acute appendicitis. At our institution, these examinations are preliminarily interpreted by radiology residents, especially when performed after hours. OBJECTIVE: To determine the accuracy of preliminary reports rendered by radiology residents in this setting. MATERIALS AND METHODS: Three hundred seventy-seven pediatric abdominopelvic MRI examinations were included. The preliminary (resident) and final (attending) radiology reports were coded as diagnosing acute appendicitis or no acute appendicitis. The concordance between resident and attending radiologist interpretations was calculated. Additionally, both resident and attending reports were compared to available surgical pathology or clinical follow-up data. RESULTS: Overall concordance rate for the diagnosis of acute appendicitis was 97.1%. Concordance for verified cases of acute appendicitis was 93.4%. Concordance rates did not differ by residents' postgraduate year levels. When compared against surgical pathology or clinical follow-up data, residents demonstrated 91.2% sensitivity and 97.6% specificity. There was no statistically significant difference in the sensitivity or specificity of resident or attending radiologist interpretations. CONCLUSION: Radiology residents demonstrate high concordance with attending pediatric radiologists in their interpretations of pediatric abdominopelvic MRI for acute appendicitis. The diagnostic performances of residents and attendings were comparable.

Fetal Origins of Asthma: A Longitudinal Study from Birth to Age 36 Years.

Rationale: Deficits in infant lung function-including the ratio of the time to reach peak tidal expiratory flow to the total expiratory time (tptef/te) and maximal expiratory flow at FRC (V̇maxFRC)-have been linked to increased risk for childhood asthma.Objectives: To examine the individual and combined effects of tptef/te and V̇maxFRC in infancy on risk for asthma and abnormalities of airway structure into mid-adult life.Methods: One hundred eighty participants in the Tucson Children's Respiratory Study birth cohort had lung function measured by the chest-compression technique in infancy (mean age ± SD: 2.0 ± 1.2 mo). Active asthma was assessed in up to 12 questionnaires between ages 6 and 36 years. Spirometry and chest high-resolution computed tomographic (HRCT) imaging were completed in a subset of participants at age 26. The relations of infant tptef/te and V̇maxFRC to active asthma and airway structural abnormalities into adult life were tested in multivariable mixed models.Measurements and Main Results: After adjustment for covariates, a 1-SD decrease in infant tptef/te and V̇maxFRC was associated with a 70% (P = 0.001) and 55% (P = 0.005) increased risk of active asthma, respectively. These effects were partly independent, and two out of three infants who were in the lowest tertile for both tptef/te and V̇maxFRC developed active asthma by mid-adult life. Infant V̇maxFRC predicted reduced airflow and infant tptef/te reduced HRCT airway caliber at age 26.Conclusions: These findings underscore the long-lasting effects of the fetal origins of asthma, support independent contributions by infant tptef/te and V̇maxFRC to development of asthma, and link deficits at birth in tptef/te with HRCT-assessed structural airway abnormalities in adult life.

First-Line Diagnostic Evaluation with MRI of Children Suspected of Having Acute Appendicitis.

Background Advances in abdominal MRI have enabled rapid, free-breathing imaging without the need for intravenous or oral contrast material. The use of MRI as the primary imaging modality for suspected appendicitis has not been previously studied. Purpose To determine the diagnostic performance of MRI as the initial imaging modality in children suspected of having acute appendicitis. Materials and Methods The study included consecutive patients 18 years of age and younger presenting with acute abdominal pain at a tertiary care institution from January 2013 through June 2016 who subsequently underwent an unenhanced MRI examination as the primary diagnostic imaging modality. Electronic medical records and radiology reports were retrospectively evaluated for the feasibility and diagnostic performance of MRI, with surgical pathology and follow-up electronic records as reference standards. Statistical analyses were performed by using simple binomial proportions to quantify sensitivity, specificity, and accuracy, and exact 95% confidence intervals (CIs) were obtained. Results After exclusions, 402 patients (median age: 13 years; interquartile range [IQR], 9-15 years; 235 female patients; 167 male patients) were included. Sedation for MRI was required in 13 of 402 patients (3.2%; 95% CI: 1.7%, 5.5%). The appendix was visualized in 349 of 402 patients (86.8%; 95% CI: 83.1%, 90%); for the remaining patients, a diagnosis was provided on the basis of secondary signs of appendicitis. The sensitivity, specificity, and accuracy of MRI as the primary diagnostic imaging modality for the evaluation of acute appendicitis were 97.9% (95 of 97; 95% CI: 92.8%, 99.8%), 99% (302 of 305; 95% CI: 97.2%, 99.8%), and 98.8% (397 of 402; 97.1%, 99.6%), respectively. Among patients with negative findings for appendicitis at MRI, an alternate diagnosis was provided in 113 of 304 patients (37.2%; 95% CI: 31.7%, 42.9%). Conclusion When performed as the initial imaging modality in children suspected of having acute appendicitis, MRI examinations had high diagnostic performance for the diagnosis of acute appendicitis and in providing alternative diagnoses. © RSNA, 2019 See also the editorial by Dillman and Trout in this issue.

A Systematic Review and Meta-Analysis of Diagnostic Performance of MRI for Evaluation of Acute Appendicitis.

OBJECTIVE: A meta-analysis was performed to determine the accuracy of MRI in the diagnosis of acute appendicitis in the general population and in subsets of pregnant patients and children. MATERIALS AND METHODS: A systematic search of the PubMed and EMBASE databases for articles published through the end of October 2014 was performed to identify studies that used MRI to evaluate patients suspected of having acute appendicitis. Pooled data for sensitivity, specificity, and positive and negative predictive values were calculated. RESULTS: A total of 30 studies that comprised 2665 patients were reviewed. The sensitivity and specificity of MRI for the diagnosis of acute appendicitis are 96% (95% CI, 95-97%) and 96% (95% CI, 95-97%), respectively. In a subgroup of studies that focused solely on pregnant patients, the sensitivity and specificity of MRI were 94% (95% CI, 87-98%) and 97% (95% CI, 96-98%), respectively, whereas in studies that focused on children, sensitivity and specificity were found to be 96% (95% CI, 95-97%) and 96% (95% CI, 94-98%), respectively. CONCLUSION: MRI has a high accuracy for the diagnosis of acute appendicitis, for a wide range of patients, and may be acceptable for use as a first-line diagnostic test.

Accuracy of Unenhanced MR Imaging in the Detection of Acute Appendicitis: Single-Institution Clinical Performance Review.

PURPOSE: To determine the accuracy of unenhanced magnetic resonance (MR) imaging in the detection of acute appendicitis in patients younger than 50 years who present to the emergency department with right lower quadrant (RLQ) pain. MATERIALS AND METHODS: The institutional review board approved this retrospective study of 403 patients from August 1, 2012, to July 30, 2014, and waived the informed consent requirement. A cross-department strategy was instituted to use MR imaging as the primary diagnostic modality in patients aged 3-49 years who presented to the emergency department with RLQ pain. All MR examinations were performed with a 1.5- or 3.0-T system. Images were acquired without breath holding by using multiplanar half-Fourier single-shot T2-weighted imaging without and with spectral adiabatic inversion recovery fat suppression without oral or intravenous contrast material. MR imaging room time was measured for each patient. Prospective image interpretations from clinical records were reviewed to document acute appendicitis or other causes of abdominal pain. Final clinical outcomes were determined by using (a) surgical results (n = 77), (b) telephone follow-up combined with review of the patient's medical records (n = 291), or (c) consensus expert panel assessment if no follow-up data were available (n = 35). Logistic regression analysis was performed to evaluate the sensitivity and specificity of MR imaging in the detection of acute appendicitis, and corresponding 95% confidence intervals were determined. RESULTS: Of the 403 patients, 67 had MR imaging findings that were positive for acute appendicitis, and 336 had negative findings. MR imaging had a sensitivity of 97.0% (65 of 67) and a specificity of 99.4% (334 of 336). The mean total room time was 14 minutes (range, 8-62 minutes). An alternate diagnosis was offered in 173 (51.5%) of 336 patients. CONCLUSION: MR imaging is a highly sensitive and specific test in the evaluation of patients younger than 50 years with acute RLQ pain that uses a rapid imaging protocol performed without intravenous or oral contrast material.

Transphyseal involvement of pyogenic osteomyelitis is considerably more common than classically taught.

OBJECTIVE: Radiologists are taught that pyogenic osteomyelitis in children rarely crosses the growth plate because terminal vessels of nutrient arteries loop at the physis, predisposing the metaphysis to hematogenous infection. However, we note that MRI frequently shows osteomyelitis involving both sides of the physis. The purpose of this article is to document our observation that pyogenic osteomyelitis crosses the growth plate more frequently in the pediatric patient population than is classically taught. MATERIALS AND METHODS: All pediatric patients (age, 2-16 years) with clinically suspected osteomyelitis from 2004 to 2009 were reviewed for transphyseal disease on a consensus basis. To reveal the statistical significance, we applied a z test to our results. We quantified rare as 20% or less and used a z test to determine whether 27 of 32 (81%) differed from rare. RESULTS: Of 32 subjects, 81% showed transphyseal infection. In our study, the z test revealed that transphyseal infection occurred significantly more often than what would be considered rare (z = 4.75, p < 0.01). CONCLUSION: In our pediatric patient population, we have documented a higher frequency of transphyseal osteomyelitis (81%) than metaphyseal osteomyelitis in pyogenic infections. When our findings are statistically compared with an expected rate of 20%, they cannot be attributed to chance alone. This raises some doubt regarding the conventional understanding of pediatric pyogenic osteomyelitis.

Angiomatoid fibrous histiocytoma: a case report and review of the literature.

Angiomatoid fibrous histiocytoma (AFH) is a rare soft tissue tumor most commonly occurring in children, adolescents, and young adults. Clinically and radiographically the lesion is easily confused with a hematoma, soft tissue hemangioma, or malignant fibrous histiocytoma. While the lesion is rare, due to the potential for local recurrence and metastasis, it is imperative to consider this lesion in the differential diagnosis of a soft tissue mass in a child or adolescent. Here, we present the clinical, radiologic, and pathologic findings of a case of AFH.

Neonatal malrotation with midgut volvulus mimicking duodenal atresia.

OBJECTIVE: The purpose of this study was to describe the clinical, imaging, and surgical findings in the cases of four neonates with radiographic findings suggesting duodenal atresia (double-bubble sign) who were subsequently found to have malrotation with midgut volvulus. CONCLUSION: When the surgical treatment of a patient with the double-bubble sign is to be delayed, an upper gastrointestinal radiographic or ultrasound study is needed to evaluate for malrotation with midgut volvulus.

Lipid infusion through malpositioned central venous catheter: head ultrasound features.

Properly placed central venous catheters have been effective in establishing prolonged access for total parenteral nutrition infusion in ill neonates. However, malposition of the catheter may lead to lethal complications. Malposition and infusion into the epidural venous plexus is most commonly diagnosed on the basis of radiographs and has been confirmed by lumbar puncture. Several studies describe catheter malposition and associated complications. None, however, demonstrate head ultrasound features. We present sonographic findings in a patient who received hyperalimentation for 15 days through a malpositioned lower extremity peripherally inserted central venous catheter.

An unusual complication of an infiltrated intravenous catheter: heterotopic ossification in a newborn.

Heterotopic ossification refers to formation of lamellar bone in soft tissues. The etiology is diverse and includes genetic, post-traumatic, and metabolic causes. Elicitation of bone morphogenic proteins are thought to play a key role in the pathogenic process. Initially, heterotopic ossification presents a clinical and radiographic challenge in that it can be mistaken for other more worrisome entities which present with calcified soft tissue masses. However, a spontaneous clinical resolution, temporal relationship to an inciting agent, and radiographic evolution to a peripherally-calcified lesion are all clues to the diagnosis. Here we present the clinical and radiographic features of heterotopic ossification as a result of an infiltrated peripheral IV.

Disseminated coccidioidomycosis in an immunodeficient 16-year-old female.

We report the case of a 16-year-old female with genetic immunodeficiency in whom pulmonary coccidioidomycosis became disseminated. Most infections due to Coccidioides immitis are self-limited and resolve over a period of weeks to months without specific treatment. In rare cases, especially those associated with immunodeficiency, the disease is found outside the confines of the chest cavity. In these cases, the most common site of dissemination is the skin. Defining the extent of dissemination often relies on diagnostic imaging.