Abnormal anatomy of the lumbosacral region imaged by magnetic resonance in children with anorectal malformations

OBJECTIVE: To investigate the frequency of lumbosacral anomalies, the association with urogenital abnormalities, and the correlation with defaecation pattern by magnetic resonance imaging (MRI). METHODS: A prospective analysis was performed of routine MRI in patients with anorectal malformations. Between 1990 and 1994, MRI was performed in 43 such patients: 31 boys and 12 girls. Twenty four had a high anorectal malformation, 16 had a low anorectal malformation, and three had Currarino's triad. MRI was performed before reconstruction in 26, and postoperatively in 17. Urogenital anomalies were found in 21. RESULTS: Abnormalities of the spinal cord and spine were found with MRI in 20 patients (46.5%); caudal regression syndrome in 10, tethered cord in two, a combination of both in three, and other spinal anomalies in five. These anomalies were found in 30% of the patients with low anorectal malformations, and in 50% with high anorectal malformations. In patients with urogenital malformations, MRI more often showed spinal anomalies (13/21, 62%) than in patients without (7/22, 32%). In high anorectal malformations, defaecation was more often a problem in patients with spinal anomalies (12/15, 80%) than in patients without (2/8, 25%). CONCLUSIONS: Spinal anomalies in the lumbosacral region were found with MRI in 46.5% of patients with anorectal malformations. Since presence of these anomalies seems to be related to clinical outcome, MRI should be performed routinely in all such patients.     

Whole body protein metabolism in children with cancer

Whole body protein synthesis and catabolism were measured using the [ring-2H5]phenylalanine and [1-13C]leucine primed constant infusion technique in 32 paediatric patients with cancer at different stages of treatment. Rates of synthesis (S) and catabolism (C) derived from the [ring-2H5]phenylalanine and [1-13C]leucine models were 4.7 (SD 1.3) (S) and 6.0 (1.5) (C) g/d/kg, and 5.5 (0.8) (S) and 6.8 (1.2) (C) g/d/kg, respectively. These results show that these two tracer techniques give similar results in this study population. Comparison of these values with results previously reported for groups of control children using the [ring-2H5]phenylalanine model (S = 3.69 and 3.93; C = 4.09 and 4.28 g/d/kg) and the [1-13C]leucine model (S = 4.32; C = 4.85 g/d/kg) show that rates of synthesis and catabolism were higher in cancer patients than in controls. Thus whole body protein turnover is increased in children under treatment for cancer. Other indices of metabolism such as plasma amino acids and intermediary metabolites were also measured and showed that, although subjects were in isotopic steady state, there were significant metabolic changes during the course of the primed constant infusions used to measure protein turnover.     

Widespread Castleman disease: CT and US findings

The widespread form of Castleman disease is a rare condition that has been recognized only recently as a disease with an aggressive, often malignant course. The authors present computed tomographic (CT) findings in six patients with this condition and ultrasound (US) findings in four of the six. CT demonstrated splenomegaly and retroperitoneal lymphadenopathy in all six patients. In one patient, CT also showed additional widespread mesenteric and peripancreatic lymphadenopathy, a large mesenteric mass adherent to the descending colon in another, and mediastinal lymphadenopathy in a third. Three patients had peripheral axillary or inguinal lymphadenopathy. Enlarged lymph nodes were 1-4 cm in diameter, and none displayed contrast enhancement on CT scans obtained with drip infusion of contrast media. On US scans, the nodes were poorly echogenic in all four cases. In no case was focal liver or splenic infiltration seen on either CT or US scans.     

Detection and characterization of primary liver cancer in rats by MS-264-enhanced MRI

A new MR contrast agent, MS-264 (Gd(1 RS)-1-(p-butylbenzyl)-DTPA), was developed to achieve hepatobiliary specificity and its potential evaluated for detecting and characterizing liver tumors in rats with chemically induced hepatocellular carcinoma (HCC). In seven rats with 66 HCC lesions, enhancements of different abdominal organs and tumors were compared on T₁-weighted images after intravenous administration of Gd-DTPA (0.3 mmol/kg) and MS-264 (0.05 mmol/kg). MR images were correlated with postmortem microangiographic and histological findings. An overall enhancement of different organs, which normalized within 24 h, was observed after Gd-DTPA and MS-264 injection. MS-264 caused a higher relative enhancement (RE) in liver (60%), compared with that of Gd-DTPA (40%), which resulted in a prompt negative contrast enhancement in 59 of 66 HCCs. All were moderately to poorly differentiated (Grades II–IV) tumors. Six of these 59 negative contrast-enhancing lesions showed a positively enhanced peritumoral rim, which corresponded histologically to malignant infiltration (n = 2) or compression (n = 4). On the other hand, six well differentiated HCCs showed prolonged positive enhancement. However, one well differentiated HCC was not positively enhanced by MS-264, probably due to poor access of the agent to the lesion. In comparison to that of the pre-contrast images, enhancement with Gd-DTPA and MS-264 increased the number of detected lesions by 22 and 42%, respectively. In this animal study, MS-264 proved to be useful in detection and characterization of primary liver cancers.     

Multiple myeloma: evaluation by CT

Although patients who have multiple myeloma usually have straightforward clinical symptoms and corroborative radiographs, in some instances, these patients will present atypically, with symptoms suggesting active disease but radiographs that are normal or nonspecific. We reviewed the records of 32 patients who had documented multiple myeloma and had undergone CT examinations, assessing the value of those examinations. Although CT is not indicated in all patients who have multiple myeloma, it is especially useful in patients who have bone pain and normal or nonspecific radiographs. CT provided confirmatory information in all cases in which lesions were seen on radiographs. CT also frequently demonstrated a greater extent of disease than could be appreciated on the radiographs.     

Supraacetabular insufficiency fractures

Insufficiency fractures in the supraacetabular region were identified in five women, aged 55-83 years. Factors contributing to the diminished resistance of their bones included postmenopausal osteoporosis, steroid therapy, radiation therapy, and rheumatoid arthritis. The supraacetabular fractures were seen on routine radiographs as hazy bands of sclerosis located immediately above and parallel to the acetabular roof. All five patients had additional fractures in the spine or pelvis. Supraacetabular insufficiency fractures may be an unsuspected cause of hip pain, especially in older women.