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Focused abdominal US has a high negative predictive value for major abdominal injury in patients with blunt abdominal trauma.

Fast spin-echo (FSE) pulse sequences enable T2-weighted imaging in a fraction of the time required for T2-weighted conventional spin-echo (CSE) imaging. Due to concerns that the altered contrast characteristics of FSE may interfere with the visualization of multiple sclerosis (MS) lesions, the sensitivity of T2-weighted FSE sequences was compared to comparably weighted CSE sequences in the imaging of the brain in 100 patients with clinically suspected MS. The proton-density FSE sequence revealed more MS lesions than its CSE counterpart, while the T2-weighted CSE sequences were found to be more sensitive than the T2-weighted FSE sequence. Contrast-to-noise ratios and signal-to-noise ratios compared favorably between sequences. Overall, there was little difference in the specificity between FSE and CSE in the diagnosis of MS. Index terms: multiple sclerosis; spin-echo imaging; fast spinecho imaging; magnetic resonance imaging; brain THE FIRST PULSE SEQUENCE to gain wide acceptance in magnetic resonance imaging (MRI) was the conventional spin-echo (CSE) pulse sequence, which is still held today as the gold standard by which other sequences are compared. However, achieving T2-weighted images with CSE has some difficulties associated with it. The primary disadvantage of CSE is the inordinately long scans with low signal averages required when obtaining T2 weighting. Several pulse sequences have been developed in order to resolve this problem, with the most popular sequence to date being the fast spin-echo (FSE) pulse sequence. First proposed in 1984 and further refined in later years (1), FSE has become accepted as a replacement for CSE in imaging the brain when T2-weighted scans are desired, despite the altered signal characteristics that can be attributed to this sequence.To date, few studies have compared FSE to the standard set by CSE in the detection of multiple sclerosis (MS) lesions (2-5). In each of these studies, a limited number of patients (6, 7, 30, and 18 patients, respectively) was scanned. In addition, a definitive diagnosis of MS had been previously made in each case. Therefore, these studies do not reflect the patient population that is referred for MRI when determining if a patient has the disease. In order to clarify at our site the appropriateness of abandoning CSE for FSE when imaging for MS, we decided to do a direct comparison of CSE with FSE in 100 patients referred with the indication of clinically suspected MS. MATERIALS AND METHODSOne hundred patients were enrolled in this study and all were referred for MRI of the brain for clinically suspected MS. The first 50 patients were randomly selected prior to imaging. The rationale behind selecting any patient with possible MS was to determine if imaging findings would be present on only one of the two pulse sequences used. The second group of 50 patients was randomly selected from a separate pool of patients who were also referred for MRI of the brain for clinically suspected MS, and had high signal intensity lesions on T2-weighted FSE images. Th...

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