An unusual round cell tumor of the tibia with granular cells.

We present the clinical, radiographic and histopathologic findings of an unusual tumor that originated in the diaphysis of the tibia in a 10-year-old boy. Clinical symptoms had been present for approximately 2 years and radiographic abnormalities for > or = 8 months before biopsy and subsequent resection of the neoplasm. The child is doing well 4 1/2 years later. Microscopically, the tumor was not typical of any bone tumor with which we are familiar. It was a round-cell tumor with extensive fibrosis, prominent cytoplasmic granularity, and isolated immunoreactivity for vimentin, epithelial membrane antigen, and antichymotrypsin. Ultrastructural examination uncovered the presence of both well-formed desmosomes and cell-associated basement membrane material in addition to abundant phagolysosomes. Classification of this tumor is a challenge; the differential diagnosis includes atypical adamantinoma, atypical Ewing's sarcoma, and small-cell osteosarcoma. We favor the former interpretation, although we raise the possibility that it may be a unique lesion.

Plate fixation of femoral shaft fractures in multiply injured children.

A study was done of twelve patients (seven boys and five girls) who, because of multiple injuries or a head injury, had been managed with compression plating of a unilateral or bilateral femoral-shaft fracture at a level-I trauma center from 1986 through 1990. The patients had a total of fifteen fractures. The average age at the time of the injuries was eight years (range, five years to nine years and eleven months). There were nine closed fractures and six open fractures; three of the open fractures were Grade I; two, Grade II; and one, Grade IIIA, according to the criteria of Gustilo et al. Each patient had an average of three associated injuries. All fifteen fractures had healed clinically and radiographically at an average of eight weeks (range, six to twelve weeks) after the operation. There were no infections. Anatomical alignment was obtained in fourteen limbs. One fracture healed with 13 degrees of anterior angulation. The compression plates were removed at an average of ten months (range, three to twenty-four months) after the index operation. At the latest follow-up evaluation (average, twenty-six months; range, eleven to fifty-seven months), no patient had restriction of activities due to the femoral fracture. Scanograms revealed overgrowth of the injured femur averaging 0.9 centimeter (range, 0.3 to 1.4 centimeters) in seven patients who had an uninjured contralateral femur. We believe that plate fixation of the femur is a good treatment option for children who have a femoral shaft fracture and a major head injury or multiple injuries, or both.

Sonographic diagnosis of intestinal malrotation in infants: importance of the relative positions of the superior mesenteric vein and artery.

OBJECTIVE: An abnormal relative position of the superior mesenteric vein and artery can be present in patients with intestinal malrotation. We undertook this retrospective study to see how often we could determine the relative position of these vessels on abdominal sonograms in infants and how often abnormal position of the vessels was associated with malrotation. MATERIALS AND METHODS: We reviewed the radiology files and medical records of 337 infants with vomiting who were referred for sonography because of possible pyloric stenosis. We used sonograms and written reports to determine the position of the superior mesenteric vessels. The position was considered normal when the superior mesenteric vein was to the right of the superior mesenteric artery on transverse sonograms. The position was considered abnormal when the vein was directly ventral to the artery or when the vein was to the left of the artery. Sonographic findings were compared with results of upper gastrointestinal series when possible and with clinical outcome. RESULTS: The relative positions of the superior mesenteric vein and artery were evident in 249 (74%) of the 337 patients. Abnormal orientation of the mesenteric vessels was detected in nine patients. In five patients, the superior mesenteric vein was located to the left of the artery, and all five had intestinal malrotation. In four patients, the superior mesenteric vein was directly ventral to the artery, and one of these had malrotation. CONCLUSION: Sonographic assessment of the relative positions of the mesenteric artery and vein is an important adjunct in the examination of infants with suspected pyloric stenosis. Patients in whom sonograms show an abnormal position of the vessels should have further examination to detect malrotation.

Normal intrahepatic bile ducts: CT depiction.

Visualization of intrahepatic bile ducts (IHBDs) at computed tomography (CT) has previously been considered evidence of biliary obstruction. The authors have found that hepatic CT enhanced with contrast material and with the use of ceramic scintillation detectors allows frequent visualization of normal IHBDs. One hundred patients without imaging, laboratory, or clinical evidence of hepatobiliary or pancreatic disease were prospectively examined to assess the frequency of visualization, location, and size of IHBDs. IHBDs were visualized in 40% of the patients and had an average size of 2.0 mm in the central part of the liver and 1.8 mm in the peripheral part of the liver. Ducts were seen in the right lobe more often than in the left lobe. There was no statistically significant relationship between visualization of IHBDs and patient age. Demonstration of IHBDs on current CT scanners is a normal finding and does not indicate biliary obstruction.

Comparison of STIR and spin-echo MR imaging at 1.5 T in 45 suspected extremity tumors: lesion conspicuity and extent.

Short inversion time inversion recovery (STIR) imaging and a double-echo spin-echo (SE) sequence at 1.5 T in 45 sequential patients with suspected extremity tumors were compared to assess the number of lesions detected, subjective conspicuity of lesions, approximate volume of abnormality detected in each lesion, and identification of peritumoral brightening in tissues adjacent to each lesion. STIR sequences enabled detection of all 45 lesions; 44 were detected with the SE sequence. Tumor appeared most conspicuous on STIR images in 35 patients (78%) and was most conspicuous on SE images in 10 patients (22%). Peritumoral brightening, which indicated either peritumoral edema or microscopic tumor infiltration, was detected in 20 patients but was detected only with STIR sequences in nine patients. It is concluded that, although STIR and SE sequences are comparable for lesion detection in the extremities, most lesions appear more conspicuous with STIR. STIR may enable detection of a greater volume of abnormality than SE sequences and may therefore have important implications for local staging and surgical and radiation therapy planning.