Multiplanar and three-dimensional multi-detector row CT of thoracic vessels and airways in the pediatric population

Multi-detector row computed tomography (CT) has changed the approach to imaging of thoracic anatomy and disease in the pediatric population. At the author's institution, multi-detector row CT with multiplanar and three-dimensional reconstruction has become an important examination in the evaluation of systemic and pulmonary vasculature and the tracheobronchial tree. In some clinical situations, multi-detector row CT with reformatted images is obviating conventional angiography, which is associated with higher radiation doses and longer sedation times. Although multi-detector row CT with multiplanar and three-dimensional reconstruction is expanding the applications of CT of the thorax, its role as a diagnostic tool still needs to be better defined. The purposes of this article are to describe how to perform multi-detector row CT with multiplanar and three-dimensional reconstruction in young patients, to discuss various reconstruction techniques available, and to discuss applications in the evaluation of vascular and airways diseases.

CT of Posttransplantation Lymphoproliferative Disorder in Pediatric Recipients of Lung Allograft

OBJECTIVE

The purpose of this study was to determine the CT and clinical findings of posttransplantation lymphoproliferative disorder in pediatric lung allograft recipients.

MATERIALS AND METHODS

We reviewed the medical records and CT examinations of 260 lung transplantations in pediatric patients and found 26 recipients who had 29 episodes of histologically proven posttransplantation lymphoproliferative disorder. The clinical and CT features of the disease, the time to diagnosis, and the outcomes were assessed.

RESULTS

The clinical presentation of posttransplantation lymphoproliferative disorder varied from asymptomatic pulmonary nodules (14/29 [48%]) detected on chest CT to specific (organ-related) and nonspecific symptoms (15/29 [52%]). Intrathoracic posttransplantation lymphoproliferative disorder occurred in 20 (69%) of 29 cases and manifested as multiple pulmonary nodules (n = 17), alveolar infiltrates (n = 2), and combined nodules and infiltrates (n = 1). In eight (28%) of 29 cases, there was extraparenchymal disease, including adenopathy, pleural effusion, and esophageal thickening and erosions. Extrathoracic posttransplantation lymphoproliferative disorder occurred in 13 cases and involved the abdomen (n = 10), paranasal sinuses (n = 2), and brain (n = 1). In the abdomen, extranodal disease was more common than nodal disease and presented as bowel wall thickening, focal mass lesions, and splenomegaly. In 18 of 29 episodes of posttransplantation lymphoproliferative disorder, the histologic diagnosis was lymphoma. The median time to diagnosis after transplantation for the 29 episodes of posttransplantation lymphoproliferative disorder was 10 months. Thirteen of the 26 patients died. The median time of survival after the diagnosis of posttransplantation lymphoproliferative disorder was 17 months.

CONCLUSION

Posttransplantation lymphoproliferative disorder in pediatric lung transplant recipients occurs with relatively high frequency in both the chest and abdomen, tends to have lymphomatous features, and results in substantial mortality rates.

Radiologic findings of 2 commonly used cardiac septal occluders with clinical correlation

Transcatheter closure of an atrial septal defect, patent foramen ovale, or post-myocardial infarction ventricular septal defect has become a safe and effective alternative to medical and surgical therapy. Although the use of transcatheter closure of septal defects is becoming increasingly more popular, there are few reports of the radiographic appearance of the closure devices. We report the chest radiographic findings in 36 patients after transcatheter closure of septal defects with Amplatzer or CardioSEAL occluders in an effort to aid radiologists in recognizing the appearances of these devices and enable them to confirm proper positioning.

Whole-body fast inversion recovery MR imaging of small cell neoplasms in pediatric patients: a pilot study

OBJECTIVE. The purpose of this study was to assess the ability of whole-body turbo short tau inversion recovery (STIR) MR imaging to detect metastases in children with small cell tumors and to compare its performance with that of conventional imaging. CONCLUSION. Early data suggest that whole-body turbo STIR MR imaging is as reliable as other conventional imaging studies for staging newly diagnosed small cell tumors in pediatric patients.

Magnetic resonance imaging of cyanotic and noncyanotic congenital heart disease

MRI has become an important imaging tool that complements echocardiography in the noninvasive evaluation of congenital heart defects. It can play a crucial role in diagnosis by assessing anatomic and functional features in CHD and identifying complications and postoperative sequelae. The performance and application of cardiac MRI require not only knowledge of the clinical question that needs to be addressed but knowledge of the anatomic characteristics of a variety of congenital heart lesions. A knowledge of the advantages and disadvantages of the different imaging sequences also is important so as to optimize and expedite the examination.

Pediatric liver magnetic resonance imaging

Imaging is a standard part of the evaluation of pediatric liver disease. Advances in MR imaging have improved the detection, characterization, and staging of hepatic lesions. Clinical information, however, is still important in selecting the best imaging study and in correctly interpreting the examination. This article addresses the clinical and imaging features of the common hepatic and biliary lesions in children. In addition, the techniques for performing hepatic MR imaging are reviewed.

Magnetic resonance imaging of nongynecologic pelvic masses in children

Pelvic neoplasms can arise from the genitourinary tract, gonads, soft tissues, or bone. The role of imaging is to confirm the presence of tumor, determine the site of origin, delineate the extent for staging and treatment planning, and serve as a baseline for monitoring response to therapy. MR imaging is well suited for the characterization and staging of pediatric pelvic tumors. This article reviews the imaging findings and staging evaluation of the common nongynecologic neoplasms in children. Prostatic, bladder, gonadal, and sacrococcygeal tumors are discussed. Gynecologic tumors are discussed elsewhere in this issue.

Magnetic resonance imaging of the adolescent female pelvis

MR imaging is well suited to evaluation of the pelvis. Ultrasonography remains the study of choice for the initial evaluation of a suspected gynecologic mass. MR imaging and computed tomography remain problem-solving tools that can help to characterize masses and stage gynecologic malignancies. MR imaging has the advantage of higher soft tissue contrast compared with computed tomography. This article reviews the MR findings of congenital anomalies and masses of the adnexa and uterus in adolescent girls.

Staging of neuroblastoma at imaging: report of the radiology diagnostic oncology group

PURPOSE

To compare the accuracies of computed tomography (CT), magnetic resonance (MR) imaging, and bone scintigraphy in staging disease in patients with neuroblastoma.

MATERIALS AND METHODS

Ninety-six children with newly diagnosed neuroblastoma were enrolled in a multicenter prospective cohort study. CT, MR, and bone scintigraphy were used to evaluate tumor stage. Sensitivity and specificity values and receiver operating characteristic (ROC) curve analyses were used to compare the accuracy of CT, MR, and scintigraphy for tumor staging.

RESULTS

Eighty-eight patients were eligible for staging analysis, and 45 patients who underwent surgery at initial diagnosis were eligible for analysis of local tumor extent. CT and MR had sensitivities of 43% and 83%, respectively (P <.01), and specificities of 97% and 88%, respectively (P >.05), for detection of stage 4 disease. Areas under the ROC curves for CT and MR were 0.81 and 0.85, respectively (P =.06); that for scintigraphy was 0.83. Addition of scintigraphy to both CT and MR increased the areas under the ROC curves to 0.90 and 0.88, respectively. Accuracy of CT and MR for staging disease confined to the chest or abdomen (stages 1, 2, and 3) was poor.

CONCLUSION

MR alone and CT and MR combined with bone scintigraphy enable the accurate detection of stage 4 disease. Both CT and MR perform poorly for local tumor staging.

Post-lung transplantation bronchiolitis obliterans syndrome: usefulness of expiratory thin-section CT for diagnosis

PURPOSE

To assess the usefulness of thin-section expiratory computed tomography (CT), as compared with that of thin-section inspiratory CT, in detecting airway obstruction and air trapping in pediatric lung transplant recipients with bronchiolitis obliterans syndrome (BOS).

MATERIALS AND METHODS

Thin-section CT scans were obtained at full inspiration and end expiration in 21 pediatric lung transplant recipients with proved BOS and in 41 transplant recipients with normal airways. True diagnosis was based on pulmonary function test results. Inspiration CT scans were scored for extent of decreased attenuation of the lung parenchyma; expiration CT scans were scored for extent of air trapping.

RESULTS

The sensitivity of inspiratory CT for enabling diagnosis of BOS was 71%; the specificity, 78%; the positive predictive value, 62%; and the negative predictive value, 84%. The sensitivity of expiratory CT for enabling diagnosis of BOS was 100%; the specificity, 71%; the positive predictive value, 64%; and the negative predictive value, 100%. Expiratory CT scores correlated more strongly (rho = 0.75, P <.01) with pulmonary function test-based scores than did inspiratory CT scores (rho = 0.48, P <.01). Nominal logistic regression analysis revealed that expiratory CT was a more powerful predictor of true diagnosis (P <.01) than was inspiratory CT (P =.10).

CONCLUSION

Expiratory CT is sensitive for depicting BOS-related airway abnormalities and may be more useful than inspiratory CT for diagnosis of small airway obstruction.

Impact of financial incentives on documented immunization rates in the inner city: results of a randomized controlled trial

OBJECTIVE

This study determined the effect of 2 financial incentives---bonus and enhanced fee-for-service---on documented immunization rates during a second period of observation.

METHODS

Incentives were given to 57 randomly selected inner-city physicians 4 times at 4-month intervals based on the performance of 50 randomly selected children. Coverage from linked records from all sources was determined for a subsample of children within physician offices.

RESULTS

Up-to-date coverage rates documented in the charts increased significantly for children in the bonus group (49.7% to 55.6%; P <.05) and the enhanced fee-for-service group (50.8% to 58.2%; P <.01) compared with the control group. The number of immunizations given by these physicians did not change significantly, although the number of immunizations given by others and documented by physicians in the bonus group did increase (P <.05). Up-to-date coverage for all groups increased from 20 to 40 percentage points when immunizations from physician charts were combined with other sources.

CONCLUSIONS

Both financial incentives produced a significant increase in coverage levels. Increases were primarily due to better documentation not to better immunizing practices. The financial incentives appeared to provide motivation to physicians but were not sufficient to overcome entrenched behavior patterns. However, true immunization coverage was substantially higher than that documented in the charts.

Magnetic resonance imaging of musculoskeletal soft tissue masses

The role of MR imaging in the evaluation of children with large, deep, or infiltrative soft tissue masses is to characterize and determine the extent of the lesion for treatment planning. There are a small number of soft tissue tumors with MR imaging appearances characteristic enough to allow a specific diagnosis, obviating biopsy. In the remaining cases with nonspecific imaging appearances, MR imaging is used for anatomic staging, but tissue sampling is still required for determining histology and grading.