John B. Shields

Magnetic resonance imaging of lesions of synovial origin

Three patients with histologically differing lesions of synovial origin and two with synovial cysts, one of which was a dissecting popliteal cyst, were examined by magnetic resonance imaging (MR) and computerized tomography (CT). The three histologically proven synovial lesions were synovial sarcoma, diffuse giant cell tumor of tendon sheath, and synovial chondromatosis. In two of the five patients MR provided better anatomic and morphologic appreciation than CT, while in the others they were of equal value. CT demonstrated calcification in two of the lesions while on MR calcification could be identified in only one patient where it outlined the mass. MR did not demonstrate calcification in the substance of the diffuse giant cell tumor of tendon sheath. Coronal, transverse, and sagittal images of magnetic resonance graphically demonstrated the extent of the soft tissue masses and their relationship to bone, vessels, and soft tissue structures. Synovial sarcoma had a shorter T1 than diffuse giant cell tumor of tendon sheath (these two lesions being of comparable size) and also had a uniformly longer T2. The dissecting popliteal cyst showed the most intense signals on the T1 weighted images, while the uncomplicated synovial cyst showed a long T1. On the T2 weighted images, each type of cyst showed a long T2. The variance and overlap of intensity of MR signals suggest limited specificity in predicting the histologic nature of the synovial lesion.

The role of computed tomography in pelvic fractures.

Adequate radiologic demonstration of the extent of pelvic fractures facilitates planning of their treatment by the orthopedic surgeon. Traditionally, this evaluation has been by conventional radiology. This report details results of computed tomography (CT) in the evaluation of pelvic fractures in 34 patients. In most cases. CT was able to identify and delineate the extent of fractures, demonstrate displacement of the involved bones, localize bone fragments and characterize joint derangements. Many of these features were better demonstrated at CT compared with conventional radiographs. In particular, in 10 patients loose bodies were seen at CT that were not evident on conventional radiography. The extent of associated soft tissue injury is also well shown by CT and demonstrated peripelvic or intraarticular fluid collections can be aspirated under CT guidance to rule out sepsis. This study suggests that CT is useful in the assessment of major pelvic fractures.

Body computed tomography findings in systemic lupus erythematosus

Fifty-five computed tomography scans in 27 patients with systemic lupus erythematosus were reviewed. The most frequent indication for scanning was suspected intraabdominal sepsis, and the most frequent finding was mild lymphadenopathy. Renal abnormalities were: subcapsular hematoma, focal defects, overall enlargement, and diminution of size. Other findings included serositis, bowel wall thickening with pneumatosis intestinalis, pancreatic pseudocyst, and hepatic and splenic enlargement. Five abscesses were found that were indistinguishable from other fluid collections. Computed tomography was helpful in clinical evaluation and in some cases changed management.

Embolization of blunt trauma in the pediatric patient

The use of embolization for control of hemorrhage following blunt trauma is well accepted in the adult population. This paper describes 2 cases in which embolization techniques were used successfully to control hemorrhage following blunt trauma in pediatric patients.