Rosalind B. Dietrich

MR imaging of bone marrow in children.

The magnetic resonance (MR) images of the knees and hips of children with systemic diseases involving bone marrow were correlated with their marrow histology and compared with the images of asymptomatic normal children. In normal children the intensity of the MR signal from the bone marrow of the knees and hips was uniform throughout the metaphyses and diaphyses. In contradistinction the MR signal was uniformly diminished for the hypercellular marrow of patients with sickle cell anemia, was similar to normal for the hypocellular hyperfatty marrow of untreated aplastic anemia, and was nonuniform and patchy for leukemic marrow.

Acquired cystic kidney disease in children undergoing long-term dialysis.

Acquired cystic kidney disease (ACKD) occurs in adult patients undergoing long-term dialysis. Early detection is important because clinically significant hematuria and malignancies are associated with ACKD. We evaluated by magnetic resonance imaging (MRI) and ultrasonography (US) the incidence of ACKD in 15 patients aged 7.3–21.6 years (mean 15.9 years) with non-cystic primary renal disease. Nine patients had been treated with peritoneal dialysis only, and 6 with both hemodialysis and peritoneal dialysis for 24–73 months (mean 37 months). Three patients (20%) had no cysts. In 5 patients (33%) with bilateral multiple cysts, the diagnosis of ACKD was made by MRI and US. In another 5 patients, solitary cysts were localized to one kidney by MRI, and in 2 patients solitary cysts were seen in both kidneys. This study documents that ACKD is not limited to older patients with end-stage renal disease. Early detection of these cysts can be accomplished by MRI and is warranted since 1 patient developed neoplastic tubular changes which can precede tumor formation.

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.

Acute renal allograft rejection: comparative value of ultrasound versus magnetic resonance imaging

Both magnetic resonance imaging (MRI) and ultrasound (US) have been reported to be useful in differentiating between acute allograft rejection and other causes of graft dysfunction in renal transplantation. The aim of this study was to evaluate the comparative usefulness of these techniques in the assessment of patients with acutely rising serum creatinine levels. Seventeen patients with 19 episodes of acute serum creatinine elevations were evaluated for the presence of acute rejection. The ultimate diagnoses of acute rejection were based on either renal pathological findings, or the response to standard antirejection therapy. Clinical, US and MRI diagnoses were assessed independently, without knowledge of the results of the other evaluation techniques. We found that US alone was useful in diagnosing acute rejection (x2 = 4.95, P less than 0.05), and when taken in the clinical setting was an added advantage (x2 = 6.68, P less than 0.01). MRI did not increase the diagnostic accuracy significantly.

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.

Magnetic Resonance Imaging of Iron Overload in Children Treated with Peritoneal Dialysis

The ability of magnetic resonance imaging (MRI) to detect iron overload in children with end-stage renal disease (ESRD) was studied in 18 multiply transfused patients, aged 15.5 +/- 4.8 years, and 5 nontransfused children without evidence of renal disease. In the transfused patients, the serum ferritin (SF) level was compared to (a) a subjective rating of signal intensity of MRI images (scale of 0-10), (b) mean T1 values of liver and spleen, and (c) computer-assisted measurements of spin echo intensity (SEI) of liver, spleen, muscle and fat tissue. On subjective evaluation, the mean signal intensity was significantly lower in transfused patients than in controls and a significant correlation with the SF levels was observed for ratings of both liver and spleen. Mean T1 values of liver and spleen did not correlate with the SF levels. On computer analysis, the ratios of SEI of fat/liver, fat/spleen, muscle/liver and muscle/spleen were significantly correlated with the SF levels as well as the subjective evaluation sources. These data indicate that MRI is a suitable technique of documenting the presence and degree of iron overload in multiply transfused children with ESRD.