M. Ines Boechat

Peak trabecular vertebral density: a comparison of adolescent and adult females

SummaryTo determine when spinal bone density reaches its peak, the trabecular vertebral density was assessed, via quantitative computed tomography, among females from two age groups: (1) adolescents (aged 14–19 years; n=24); and (2) young adults (aged 25–35 years; n=24). The adolescent girls had a higher mean trabecular vertebral density (P<0.01), suggesting that spinal density reaches its peak around the time of cessation of longitudinal growth and epiphyseal closure.

Skeletal Age Determinations in Children of European and African Descent: Applicability of the Greulich and Pyle Standards

This study assesses the value of the Greulich and Pyle method in determining the skeletal ages of healthy American children of European and African descent born after the year 1980. The hand and wrist radiographs of 534 children (265 boys, 269 girls; 260 European-Americans [EA], 274 African-Americans [AA]), ages 0 to 19 y, were analyzed by two experienced pediatric radiologists blinded to the chronological age of the subjects. A difference score was calculated for each subject by subtracting chronological age from the mean bone ages scores provided by the two raters. One group t-tests were performed to verify the hypothesis that the mean difference score was equal to zero. Skeletal age determinations by the two radiologists showed a high degree of agreement by intraclass correlation coefficient (r = 0.994). The range of values for differences in skeletal and chronological ages was very wide, indicating great individual variability. Comparisons between skeletal and chronological age only reached statistical significance in EA prepubertal girls, whose skeletal ages were delayed, on average, by three months (t = −2.9;p = 0.005). Mean difference between skeletal and chronological age in prepubertal children of African descent was 0.09 ± 0.66 y, while that in children of European descent was −0.17 ± 0.67 y; (t = 3.13;p = 0.0019). On average, the bone ages of 10% of all prepubertal AA children were 2 SD above the normative data in the Greulich and Pyle atlas, while the bone ages of 8% of all prepubertal EA children were 2 SD below. In contrast to the racial differences observed in prepubertal children, EA postpubertal males had significantly greater values for bone age than AA postpubertal males (t = 2.03;p = 0.05). In conclusion, variations in skeletal maturation in prepubertal children are greater than those reflected in the Greulich and Pyle atlas; prepubertal American children of European descent have significantly delayed skeletal maturation when compared with those of African descent; and, postpubertal EA males have significantly advanced skeletal maturation when compared with postpubertal AA males. New standards are needed to make clinical decisions that require reliable bone ages and to accurately represent a multiethnic pediatric population.

Recombinant human growth hormone treatment of children following renal transplantation

Nine growth-retarded renal allograft recipients received either thrice weekly or daily subcutaneous recombinant human growth hormone (rhGH) for 6–30 months. The annualized growth velocity for the initial year of rhGH treatment was significantly greater than that of the preceding year (2.5±2.1 vs 5.7±2.7;P<0.0001). There was no advancement in bone age greater than the increase in chronological age, no significant increase in the mean fasting serum glucose or insulin levels, nor significant decrease in the calculated creatinine clearance following rhGH treatment. However, two patients experienced rejection episodes following rhGH treatment indicating the potiental adverse consequences of the treatment on allograft function. This will require further delineation in prospective controlled studies. The serum insulin-like growth factor-1 levels significantly increased at 6 months (P<0.009) and 12 months (P<0.002) following rhGH treatment compared with baseline values. These preliminary data indicate that rhGH treatment may be effective in improving the growth velocity of growth-retarded renal allograft recipients.

Implementation of a large-scale picture archiving and communication system

This paper describes the implementation of a large-scale picture archiving and communication system (PACS) in a clinical environment. The system consists of a PACS infrastructure, composed of a PACS controller, a database management system, communication networks, and optical disk archive. It connects to three MR units, four CT scanners, three computed radiography systems, and two laser film digitizers. Seven display stations are on line 24 h/day, 7 days/wk in genitourinary radiology (2K), pediatric radiology in-patient (1K and 2K) and outpatient (2K), neuroradiology (2K), pediatric ICU (1K), coronary care unit (1K), and one laser film printing station. The PACS is integrated with the hospital information system and the radiology information system. The system has been in operation since February 1992. We have integrated this PACS as a clinical component in daily radiology practice. It archives an average of 2.0-gigabyte image data per workday. A 3-mo system performance of various components are tabulated. The deployment of this large-scale PACS signifies a milestone in our PACS research and development effort. Radiologists, fellows, residents, and clinicians use it for case review, conferences, and occasionally for primary diagnosis. With this large-scale PACS in place, it will allow us to investigate the two critical issues raised when PACS research first started 10 yrs ago: system performance and cost effectiveness between a digital-based and a film-based system.

Noonan syndrome associated with neuroblastoma : a case report

Abstract We report a case of a child with Noonan phenotype and incidental radiographic findings of mediastinal neuroblastoma. Recent studies have reported an increased association of Noonan syndrome with some malignancies, and the case we present here is the first reported case to our knowledge of an association of neuroblastoma with Noonan syndrome.

MAGNETIC RESONANCE IMAGING OF WILMS TUMOR

Magnetic resonance imaging (MRI) in 4 children with Wilms tumor suggests the usefulness of this newer imaging modality in evaluating the organ of origin and defining the extent of Wilms tumor. Coronal T1-weighted images were the most useful pulsing sequence for evaluating these children.

Osteomalacia in a hemodialysis patient receiving an active vitamin D sterol

Background A 17-year-old Filipino male hemodialysis patient presented for renal transplant evaluation. He had significant skeletal abnormalities characterized by bone pain, an inability to walk, and secondary hyperparathyroidism despite therapy with an active vitamin D sterol (paricalcitol).Investigations The patient underwent a physical examination, and his serum levels of calcium, phosphorus, alkaline phosphatase, parathyroid hormone, aluminum and 25-hydroxycholecalciferol (25OH-vitamin D) were determined. X-rays of hips and lower extremities, MRI, and bone histomorphometry after double tetracycline labeling were performed.Diagnosis Osteomalacia associated with low 25OH-vitamin D levels.Management Monthly therapy with ergocalciferol (vitamin D2) and discontinuation of paricalcitol.

Idiopathic infantile arterial calcification: imaging evaluation and the usefulness of MR angiography

Idiopathic infantile arterial calcification (IIAC) is a rare condition characterized by extensive calcification and stenosis of large and medium-size arteries. The etiology of the disease is unknown. However, the inheritance pattern has been shown to be autosomal recessive. The clinical presentation is variable, including cardiac failure (most common clinical finding), hypertension, and respiratory failure. Plain radiography, sonography and MRI can aid in the diagnosis. We present a case in which contrast-enhanced MR angiography with breath-hold and cardiac gating techniques allowed complete evaluation of the extent of this disease.

Women in pediatric radiology

Women represent a significant proportion of pediatric radiologists in the United States, as shown on surveys by the American College of Radiology (ACR) and the Society for Pediatric Radiology (SPR). This review discusses the characteristics of this subgroup of specialists and issues uniquely related to them.

Experience With Phosphor Imaging Plates--Clinical Experience In Pediatric Radiology

Although new imaging modalities routinely use digital imaging processing and display, digitization of conventional radiographic procedures has been slower to gain acceptance. Digital radiology potentially offers greater flexibility in image manipulation and display. It also has potential for high density storage of images and both local and long distance transmission of image data. Because of smaller film size and the potential reduction in the number of repeat examinations performed due to exposure errors because of the larger dynamic range of the imaging plate, reduced examinations costs could ensue. Of particular importance in our area, where we are dealing with a pediatric population, is the potential decrease in radiation dosage associated with computed radiology (CR) systems.