The misinterpretation rates of radiology residents on emergent neuroradiology magnetic resonance (MR) angiogram studies: correlation with level of residency training.

The purpose of this study was to determine the discrepancy rates of radiology residents interpreting emergent neck and Circle of Willis magnetic resonance angiography (MRA) studies and to detect any adverse clinical outcomes. Three hundred seventeen MRA studies given preliminary reading by radiology residents were retrospectively reviewed over a 2-year period. Discrepancies were classified as either false negatives (failure to diagnose abnormalities) or false positives (misinterpreting normal scans as abnormal). The overall discrepancy rate was 12.1% for Circle of Willis MRA and 7.9% for neck MRA. Fourth-year residents had the lowest discrepancy rates (7.7%), but this was not statistically significant. The most common misses were stenosis greater than 70% (n = 9) and aneurysm (n = 12). No adverse clinical outcome was detected mainly due to rapid turnaround time for final reporting.

Discrepancy rates of on-call radiology residents' interpretations of CT angiography studies of the neck and circle of Willis.

OBJECTIVE: The purpose of our study was to determine the discrepancy rates of radiology residents' interpretations of emergent CT angiography (CTA) studies of the neck and circle of Willis and to assess any adverse clinical outcomes. MATERIALS AND METHODS: Five hundred thirty-eight CTA studies (287 circle of Willis and 251 neck) ordered emergently after hours and given preliminary readings by radiology residents from January 1, 2006, through December 31, 2007, were retrospectively reviewed. Discrepancies between the interpretations of radiology residents and the final reports of neuroradiology attending physicians were classified as either false-negatives (failure to recognize abnormalities) or false-positives (misinterpreting normal scans as abnormal). Discrepancies that could affect patient care or clinical care were considered major. RESULTS: Overall, the discrepancy rate was 13.6% for circle of Willis CTA and 13.5% for neck CTA. The misinterpretation rate of first-year residents was 19.5%, which was statistically significant compared with more senior-level residents (p = 0.05). There were 57 false-negative interpretations. The most common misses were stenosis greater than 50% (n = 16) and aneurysm (n = 15), and the most common false-positive was overcalling a potential intracranial aneurysm (n = 7). No adverse clinical outcomes were detected. CONCLUSION: The discrepancy rate between interpretations by on-call radiology residents and attending physicians of neuroradiology CTA studies was higher than expected at 13.6%, with a statistically significant greater miss rate among the most junior residents, which may be mitigated by recent changes with respect to the radiology residents' overnight call. No adverse clinical outcome was detected.

Widespread natural variation in murine natural killer T-cell number and function.

Natural killer T (NKT) cells comprise a novel T-lymphocyte subset that can influence a wide variety of immune responses through their ability to secrete large amounts of a variety of cytokines. Although variation in NKT-cell number and function has been extensively studied in autoimmune disease-prone mice, in which it has been linked to disease susceptibility, relatively little is known of the natural variation of NKT-cell number and function among normal inbred mouse strains. Here, we demonstrate strain-dependent variation in the susceptibility of C57BL/6J and BALB/cJ mice to NKT-mediated airway hyperreactivity, which correlated with significant increases in serum interleukin-4 (IL-4) and IL-13 elicited by the synthetic glycosphingolipid alpha-galactosylceramide. Examination of NKT-cell function revealed a significantly greater frequency of cytokine-producing NKT cells in C57BL/6J versus BALB/cJ mice as well as significant differences in the kinetics of NKT-cell cytokine production. Extension of this analysis to a panel of inbred mouse strains indicated that variability in NKT-cell cytokine production was widespread. Similarly, an examination of NKT-cell frequency revealed a significantly greater number of liver NKT cells in the C57BL/6J mice versus BALB/cJ mouse livers. Again, examination of a panel of inbred mouse strains revealed that liver NKT-cell numbers were quite variable, spanning over a 100-fold range. Taken together, these results demonstrate the presence of widespread natural variation in NKT-cell number and function among common inbred mouse strains, which may have implications for the examination of the influence of NKT cells in immune responses and disease pathogenesis among different genetic backgrounds.