Journal of computer assisted tomography
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J Comput Assist Tomogr · Jan 1992
Signal-to-noise and contrast in fast spin echo (FSE) and inversion recovery FSE imaging.
Fast spin echo (FSE) imaging has recently experienced a renewed enthusiasm in the clinical setting for its ability to provide high contrast T2-weighted images in short imaging times. This article evaluates the signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) properties of the FSE sequence, inversion recovery (IR) FSE sequence, and conventional SE imaging. The results indicate that FSE imaging displays similar contrast properties to SE imaging, but that the SNR and CNR are improved secondary to the longer TRs and longer effective TEs that may be used. ⋯ The addition of a slice selective inversion pulse in IR-FSE allows rapid generation of IR images with image contrast similar to that of conventional IR sequences. When used with a multicoil array for abdominal, pelvic, and spine imaging, the IR-FSE sequence produces images that are virtually free of motion artifact from the subcutaneous fat immediately adjacent to the coils. Both FSE and IR-FSE, when compared with SE imaging, provide superior image contrast and SNR in reduced imaging time.
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J Comput Assist Tomogr · Jan 1992
Case ReportsMyxopapillary ependymoma with extensive sacral destruction: CT and MR findings.
There have been few reports documenting primary myxopapillary ependymomas in the sacrococcygeal region that result in extensive involvement of the sacrum. We present a 21-year-old man whose CT and MR findings showed massive bony destruction of the sacrum and a large lobulated soft tissue mass. Myxopapillary ependymoma should be included along with giant cell tumor, chordoma, and aneurysmal bone cyst in the differential diagnosis of a destructive osteolytic sacral lesion.
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J Comput Assist Tomogr · Jan 1992
Significance of bowel wall enhancement on CT following blunt abdominal trauma in childhood.
Over a 3-year period, 12 children with blunt abdominal trauma were noted to have intense bowel wall enhancement (BWE) on CT. In four, with fatal CNS injury, there was no evidence of bowel perforation, and the changes may be related to the hypovolemic complex. In the remaining eight patients with a gastrointestinal perforation, BWE was associated with the presence of diffuse or focal bowel wall thickening and free peritoneal fluid. ⋯ When combined with bowel thickening and free fluid, perforation and peritonitis should be strongly suggested. Enhancement and thickening should suggest perforation even if other visceral injury is present to account for the free fluid. Surgical intervention should thus be more strongly considered when bowel wall thickening accompanies BWE.