Oscar M. Navarro

The impact of imaging in the management of intussusception owing to pathologic lead points in children. A review of 43 cases.

Objective. To review the imaging appearances, management and outcome of a large number of children with intussusception owing to pathologic lead points (PLP) in an attempt to define the role of various imaging modalities in this clinical setting.¶Materials and methods. Review of the records and imaging studies of 43 children with intussusception due to PLP diagnosed between 1986 and 1999.¶Results. The commonest PLP found were Meckel diverticulum, polyps, Henoch-Schönlein purpura and cystic fibrosis. PLP were depicted on sonography in 23 (66 %) of 35 patients, on computed tomography in 5 (71 %) of 7, on air enema in 3 (11 %) of 28, and on barium enema in 6 (40 %) of 15. Air enema successfully reduced 60 % of the intussusceptions. Nine children had recurrent intussusceptions.¶Conclusion. Sonography depicted two-thirds of PLP and provided a specific diagnosis in nearly one-third of our series. Our review does not provide sufficient data on how to continue the investigation of those patients in whom sonography does not depict a PLP but in whom there is a high index of suspicion for its presence. It remains a diagnostic challenge as to how to search for PLP in these patients, and other imaging modalities have to be requested according to each particular case.

Intussusception. Part 3: Diagnosis and management of those with an identifiable or predisposing cause and those that reduce spontaneously.

In the previous two parts of this review on intussusception, the diagnosis and management of symptomatic, “idiopathic” ileocolic and ileoileocolic intussusceptions, which are considered to result from hyperplasia of lymphoid tissue in the distal ileum, were discussed. In this third part, those intussusceptions with an identifiable cause including pathologic lead point, those due to gastrojejunostomy or other feeding tubes, and those that are seen in the postoperative period as well as those that may be asymptomatic or may reduce spontaneously (usually limited to the small bowel) are discussed.

Spontaneous reduction of intussusception: clinical spectrum, management and outcome

Background. To analyze the spectrum of clinical features, management and outcome of children with documented spontaneous reduction of intussusception (SROI).¶Materials and methods. Review of records of 50 children (33 boys, ¶17 girls; age range 11 days–15 years; mean age 4 years) with documented SROI, in whom intussusception was initially diagnosed by sonography (US) in 44, air enema in 2, and computed tomography in 4, in the 6-year period 1992–1998.¶Results. Symptoms suggestive of intussusception were present in 21 (3 of whom had Henoch-Schönlein purpura and 4 had previous ileocolic intussusception reduced by air enema). Intussusception was an incidental finding in the other 29, in 28 of whom the finding was in the small bowel. Intussusception was limited to the small bowel in 43 and was ileocolic in 7. SROI was usually documented on US. Laparotomy performed in only 4 showed no evidence of intussusception or pathologic lead point. Outcome in all patients was favorable.¶Conclusions. SROI may present in symptomatic or asymptomatic children and occurs more commonly than previously reported. These intussusceptions are usually short-segment, small-bowel intussusceptions with no recognizable lead point. In asymptomatic patients, conservative observation is warranted. Intervention should be dictated by the clinical findings in symptomatic patients.

Pediatric Soft-Tissue Tumors and Pseudo-tumors: MR Imaging Features with Pathologic Correlation

A wide spectrum of entities may give rise to soft-tissue masses in children, including benign and malignant tumors, pseudotumors, and both neoplastic and nonneoplastic vascular lesions. Because of its excellent tissue contrast, multiplanar capability, and lack of ionizing radiation, magnetic resonance (MR) imaging has become the modality of choice in the evaluation of deep and large soft-tissue masses in children. In the vast majority of cases, however, accurate interpretation of the MR imaging findings requires correlation with the clinical findings. For example, in most posttraumatic and inflammatory pseudotumors, the clinical history is fundamental to establishing the diagnosis. In the evaluation of periarticular cysts, the location of the mass and its relationship to a joint are crucial for diagnosis, whereas in the evaluation of vascular lesions, including hemangiomas and vascular malformations, clinical findings combined with MR imaging findings are needed for accurate diagnosis in most cases. The identification of fat within adipocytic tumors is useful, but tissue biopsy may be required for final diagnosis. Nevertheless, MR imaging is useful in determining the origin and character of pediatric soft-tissue masses, defining their extent and their relationship to adjacent structures, and performing posttherapy follow-up.

Correlation of sonographic findings and outcome in necrotizing enterocolitis

BackgroundThere is little in the literature regarding the use of gray-scale and Doppler sonography of the bowel in necrotizing enterocolitis (NEC) and how findings depicted by this modality might assist in predicting outcome and influence management.ObjectiveTo correlate sonographic findings with outcome in NEC.Materials and methodsThis was a retrospective analysis of clinical and abdominal ultrasonography (AUS) findings in NEC from January 2003 to December 2005. AUS findings were evaluated for portal venous gas, free gas, peritoneal fluid, bowel wall thickness, echogenicity, perfusion and intramural gas. Patients were categorized into two groups, according to their outcome.ResultsA total of 40 infants were identified who had AUS for NEC prior to any surgical intervention. Group A comprised 18 neonates treated medically and recovered fully, and group B comprised 22 neonates who required surgery or died. Free gas (six patients) and focal fluid collections (three patients) were only found in group B. Increased bowel wall echogenicity, absent bowel perfusion, portal venous gas, bowel wall thinning, bowel wall thickening, free fluid with echoes and intramural gas were seen in both groups, but more frequently in group B. Anechoic free fluid was seen more frequently in group A. Increased bowel perfusion was seen equally in both groups.ConclusionAn adverse outcome was associated with the sonographic findings of free gas, focal fluid collections or three or more of the following: increased bowel wall echogenicity, absent bowel perfusion, portal venous gas, bowel wall thinning, bowel wall thickening, free fluid with echoes and intramural gas. Sonographic findings are useful in predicting outcome and therefore might help guide management.

Abdominal manifestations of cystic fibrosis in children

Pulmonary complications remain the main cause of mortality in cystic fibrosis, but the presenting symptoms in children are often related to gastrointestinal or pancreaticobiliary disease. Furthermore, abdominal manifestations are now seen throughout childhood, from infancy to adolescence. The child might present in the neonatal period with meconium ileus or its attendant complications. The older child might present with distal intestinal obstruction syndrome or colonic stricture secondary to high doses of pancreatic enzyme replacement. Less-common gastrointestinal manifestations include intussusception, duodenitis and fecal impaction of the appendix. Most children also show evidence of exocrine pancreatic deficiency. Radiologically, the combination of fat deposition and pancreatic fibrosis leads to varying CT and MR appearances. A higher than normal incidence of pancreatic cysts and calcification is also seen. Decreased transport of water and chloride also increases the viscosity of bile, with subsequent obstruction of the biliary ductules. If extensive, this can progress to obstructive cirrhosis, portal hypertension and esophageal varices. Diffuse fatty infiltration, hypersplenism and gallstones are also commonly seen in these patients. We present a pictorial review of the radiological appearance of these abdominal manifestations. The conditions are dealt with individually, together with typical appearances in various imaging modalities.

Pediatric soft-tissue tumors and pseudotumors: MR imaging features with pathologic correlation: part 2. Tumors of fibroblastic/myofibroblastic, so-called fibrohistiocytic, muscular, lymphomatous, neurogenic, hair matrix, and uncertain origin.

In the final part of this two-part review article on soft-tissue masses in children, the magnetic resonance (MR) imaging features, clinical findings, and pathologic findings in a wide variety of tumors, including those of fibroblastic/myofibroblastic origin, so-called fibrohistiocytic tumors, smooth-muscle tumors, skeletal-muscle tumors, tumors of uncertain differentiation, and lymphoma, are described. Other neoplasms that are not included in the World Health Organization classification of soft-tissue tumors but may be seen clinically as soft-tissue masses, specifically dermatofibrosarcoma protuberans, neurogenic tumors and pilomatricoma, are also included. In contrast to the tumors reviewed in Part 1 of this review, the MR imaging features and clinical findings of the tumors included here are largely nonspecific. However, MR imaging is useful in determining site of tumor origin, extent of disease, and relation of tumor to adjacent anatomic structures, and for follow-up after therapy. In some of these entities, the combination of findings may aid in narrowing the differential diagnosis, such as persistent low signal intensity on T1- and T2-weighted images in some fibroblastic lesions, identification of hemosiderin and a synovial origin in pigmented villonodular synovitis, or the presence of multiple target signs on T2-weighted images in deep plexiform neurofibroma. In a large number of cases, however, tissue biopsy is required for final diagnosis.

Normal Doppler Spectral Waveforms of Major Pediatric Vessels: Specific Patterns

Every major vessel in the human body has a characteristic flow pattern that is visible in spectral waveforms obtained in that vessel with Doppler ultrasonography (US). Spectral waveforms reflect the physiologic status of the organ supplied by the vessel, as well as the anatomic location of the vessel in relation to the heart. In addition, the waveforms may be affected by age- and development-related hemodynamic differences. For example, adults tend to have higher flow velocities, whereas neonates, particularly those born prematurely, have higher resistance to flow, especially in the cerebral and renal vascular beds. As Doppler US is performed with increasing frequency for vascular evaluation in children, the recognition of normal flow patterns has become imperative. Familiarity with the waveforms characteristic of specific veins and arteries in children is important. In addition, an understanding of the hemodynamic factors involved provides a useful basis for interpreting waveform abnormalities.

Metanephric adenoma of the kidney: a case report

Abstract Metanephric adenoma (MA) of the kidney is an uncommon benign epithelial tumor of the kidney that presents at any age. The histology of the lesion is well established, but the imaging findings have been described in only a few cases. We report the sonographic and computed tomographic appearance of MA in a 9-year-old girl to increase awareness among radiologists of this entity. Its recognition may facilitate nephron-sparing surgery.

The value of routine follow-up imaging in pediatric blunt liver trauma

Purpose. To evaluate the utility of routine follow-up computed tomography (CT) and/or ultrasound (US) scans in children with blunt hepatic trauma initially managed non-operatively. Materials and methods. Review of the records of 66 children with proven blunt liver injury on initial CT scan, who were initially managed non-operatively during the period January 1991 to December 1996. Follow-up CT and US studies were analyzed and correlated with clinical outcome. Results. Of the 66 children, 30 were not followed with any imaging study, 26 were followed with US only, 7 with CT only and 3 with US and CT. Disappearance of the liver lesion(s) was seen in 25 patients (range: 6 days – 14 months) and decrease in size was noted in 10. In one patient, who developed abdominal and right shoulder pain 10 days after presentation with subsequent hemoglobin drop, CT showed contrast medium extravasation into a hepatic hematoma from portal vein injury that required surgery. Conclusion. Our series suggests that in asymptomatic patients, US and CT follow-up studies do not provide the additional information needed for patient management. Therefore, we believe that in asymptomatic children with blunt hepatic trauma who are clinically stable, routine follow-up imaging studies are of very limited value.