Epipericardial Fat Pad Necrosis-A Rare Cause of Chest Pain in an Adolescent.

ABSTRACT: Epipericardial fat necrosis is a rare cause of acute pleuritic chest pain reported in approximately 40 cases. This diagnosis mimics a myocardial infarction, pulmonary embolism, or pericarditis; however, the cardiac enzymes and electrocardiogram are usually normal. We present the first reported case of epipericardial fat necrosis in an adolescent.

Diagnostic utility of intravenous contrast for MR imaging in pediatric appendicitis.

BACKGROUND: Magnetic resonance imaging (MRI) is increasingly employed as a diagnostic modality for suspected appendicitis in children. However, there is uncertainty as to which MRI sequences are sufficient for safe, timely and accurate diagnosis. Several recent studies have described different MRI protocols, including exams both with and without the use of intravenous contrast. OBJECTIVE: We hypothesized that intravenous contrast may be useful in some patients but could be safely omitted in others. MATERIALS AND METHODS: All MRI examinations (n=112) performed at our institution for evaluating appendicitis in children were retrospectively reevaluated. Exams were reread by pediatric radiologists under three conditions: With postcontrast images, Without postcontrast images, and Without/With - selective use of postcontrast sequences only when needed for diagnostic certainty. Samples were scored as positive, negative or equivocal for appendicitis. Findings were compared to pathological or clinical follow-up in the medical record. RESULTS: Without the use of intravenous contrast yielded more equivocal results (12.4%) compared to With contrast (3.4%). By selectively using postcontrast sequences, the Without/With group yielded fewer equivocal results (1.1%) compared to Without while also reducing contrast use 79.8% compared to the With contrast group. No significant differences in conditional sensitivity or conditional specificity were detected among the three groups. CONCLUSION: MRI diagnosis of acute appendicitis can be performed without contrast for most patients; injection of contrast can be reserved for only those patients with equivocal non-contrast imaging.

Importance of MRI in the diagnosis of vertebral involvement in generalized cystic lymphangiomatosis.

A 9-year-old boy presented with the sudden onset of pleuritic chest pain and on CT was found to have a large pleural effusion, mediastinal fluid, splenic lesions and multiple apparently sclerotic vertebral bodies. Subsequent MRI showed that those vertebral bodies that appeared sclerotic were in fact normal, and the vertebral bodies initially interpreted as normal had an abnormal T1 and T2 hyperintense signal on MRI and were relatively lucent on CT. MRI also demonstrated abnormal heterogeneous T2 hyperintense paraspinal tissue and several multicystic soft tissue masses. Biopsy of two adjacent vertebral bodies, one relatively sclerotic and one lucent, demonstrated findings of bony remodeling without a specific diagnosis. Biopsy of an infiltrative mediastinal mass confirmed the diagnosis of generalized cystic lymphangiomatosis. MRI should be included in the assessment of vertebral involvement in this condition because CT and biopsy findings may be nonspecific.

Differentiation of pleural effusions from parenchymal opacities: accuracy of bedside chest radiography.

OBJECTIVE: The purpose of this study was to determine, with CT as the reference standard, the ability of radiologists to detect pleural effusions on bedside chest radiographs. MATERIALS AND METHODS: Images of 200 hemithoraces in 100 ICU patients undergoing chest radiography and CT within 24 hours were reviewed. Four readers with varying levels of experience reviewed the chest radiographs and predicted the likelihood of the presence of an effusion or parenchymal opacity on independent 5-point scales. The results were compared with the CT findings. RESULTS: All readers regardless of experience had similar accuracy in detecting pleural effusions. Among 117 pleural effusions, 66% were detected on chest radiographs (53%, 71%, and 92% of small, moderate, and large effusions) with 89% specificity. Similarly, 65% of all parenchymal opacities were detected on chest radiographs, also with 89% specificity. Most (93%) of the misdiagnosed pulmonary opacities were simply not seen. Meniscus, apical cap, lateral band, and subpulmonic opacity were highly specific findings but had low individual sensitivity for effusions. The finding of homogeneous opacity, including both layering and gradient opacities, was the most sensitive sign of effusion. Atelectasis can occasionally mimic the pleural veil sign of effusion, accounting for most false-positive findings. CONCLUSION: Radiologists interpreting bedside chest radiographs of ICU patients detect large pleural effusions 92% of the time and can exclude large effusions with high confidence. However, small and medium effusions often are misdiagnosed as parenchymal opacities (45%) or are not seen (55%). Pulmonary opacities often are missed (34%) but are rarely misdiagnosed as pleural effusions (7%).

Hyperirritable stomach as a cause of nausea and vomiting: clinical and radiographic findings.

OBJECTIVE: The purpose of our study was to characterize the clinical and radiographic features of the hyperirritable stomach and to determine if it is associated with extraintestinal causes of nausea and vomiting in the absence of gastric outlet obstruction, gastroparesis, or intestinal obstruction or ileus. CONCLUSION: The hyperirritable stomach was characterized on barium studies in 15 patients by rapid emesis of ingested barium, a collapsed stomach with little or no retained debris or fluid, and normal emptying of residual barium into nondilated duodenum and proximal jejunum. Fourteen (93%) of these 15 patients had extraintestinal causes of nausea and vomiting, and 13 (93%) of 14 with clinical follow-up had marked improvement or resolution of symptoms after treatment. Radiologists therefore should evaluate the stomach and duodenum even after rapid emesis of ingested barium in patients with nausea and vomiting to differentiate a hyperirritable stomach from mechanical or functional gastrointestinal obstruction.

Sling left pulmonary artery with patent type IIA tracheobronchial anomaly and imperforate anus.

We present a 3-month-old boy with a type IIA sling left pulmonary artery associated with imperforate anus and rectourethral fistula. Tracheobronchial abnormalities are demonstrated using multidetector CT with 3-D volume rendering of the airways. This case represents a novel variant of an already rare entity with an unusually high right upper lobe bronchus and no evidence of associated tracheobronchial stenosis.

Advances in uroradiologic imaging in children.

Diagnostic imaging of pediatric urologic disorders is continuously changing as technologic advances are made. Although the backbone of pediatric urologic imaging has been ultrasound, voiding cystourethrography, and radionuclide scintigraphy, newer and advanced modalities are becoming increasingly important. This article discusses the techniques and clinical applications of three such imaging modalities as they pertain to pediatric urologic disorders: (1) MR urography; (2) advanced ultrasound (harmonic imaging, three-dimensional, and voiding urosonography); and (3) CT angiography.

Pediatric urologic advanced imaging: techniques and applications.

Diagnostic imaging of pediatric urologic disorders is continuously changing as technological advances are made. Although the backbone of pediatric urologic imaging has been ultrasound (US), voiding cystourethrography (VCUG), and radionuclide scintigraphy, newer and advanced modalities are increasingly becoming important. The aim of this review is to discuss the techniques and clinical applications of 3 such imaging modalities as they pertain to pediatric urologic disorders: MR urography, advanced US (harmonic imaging, 3D, voiding urosonography), and CT angiography.