William G. Berger

Assessing radiology resident preparedness to manage IV contrast media reactions using simulation technology

Investigate whether radiology residents make correct diagnosis of contrast media reactions and evaluate their treatment of reaction using simulation technology. Residents were presented with a test scenario of patient given IV contrast having anaphylactic reaction. A computer-run mechanical mannequin that simulates, with mathematical, pharmacokinetic, pharmacodynamic and cardiovascular algorithms, was used. Sessions were evaluated with respect to whether residents performed key actions to treat anaphylaxis. Times were recorded. All residents recognized the contrast reaction and initiated basic actions. As the scenario progressed and patient deteriorated, all recognized need to intubate, but intubation performance varied significantly. Radiology residents generally not prepared to deal with IV contrast reactions. Simulation technology to practice key actions would improve their preparedness.

Pulmonary nodule detection: what features attract attention?

The goal of the study was to determine if there are certain physical features of pulmonary nodules that attract visual attention and contribute to increased recognition and detection by observers. A series of posteroanterior chest images with solitary pulmonary nodules were searched by six radiologists as their eye-position was recorded. The signal-to-noise ratio, size, conspicuity, location, and calcification status were measured for each nodule. Dwell parameters were correlated with nodule features and related to detection rates. Only nodule size (F = 5.08, p = 0.0254) and conspicuity (F = 4.625, p = 0.0329) influenced total dwell time on nodules, with larger more conspicuous nodules receiving less visual attention than smaller less conspicuous nodules. All nodule features examined influenced overall detection performance (p < 0.05) even though most did not influence visual search and attention. Individual nodule features do not attract attention as measured by “first hit” fixation data, but certain features do tend to hold attention once the nodule has been fixated. The combination of all features influences whether or not it is detected.

Potential use of a large-screen display for interpreting radiographic images

Radiology has readily made the transition to the digital reading room. One commodity left behind when moving to digital displays however is display real estate. Even with multiple monitors radiologists cannot display numerous images as they did on a film alternator. We evaluated a large-screen rear-projection display (Philips Electronics) for potential use in radiology. Resolution was 1920 x 1080 with a 44-inch diagonal size and it was a color display. For comparison we used the IBM 9 Mpixel color display (22-inch diagonal) set to a comparable resolution and maximum luminance. Diagnostic accuracy with a series of bone images with subtle fractures and six observers was comparable (F = 0.3170, p = 0.5743) to traditional computer monitor. Viewing time, however, was significantly shorter (t = 6.723, p < 0.0001) with the large display for both normal and fracture images. On average, readers sat significantly closer (t = 5.578, p = 0.0026) to the small display than the large display. Four of the 6 radiologists preferred the smaller display, judging it to yield a sharper image. Half of the readers thought the black level was better with the large display and half with the small display. Most of the radiologists thought the large-screen display has potential for use in conferencing situations or those in which multiple viewers need to see images simultaneously.

Imaging Evaluation of the Solitary Pulmonary Nodule: Self-Assessment Module

The educational objectives for this self-assessment module are for the participant to exercise, self-assess, and improve his or her understanding of the imaging evaluation of the solitary pulmonary nodule.

Evaluation of head CT exams - resident and attending diagnoses

The goal of this study was to evaluate performance of radiology resident in interpretation of head CT exams ordered by emergency room physicians, and to compare their accuracy with the attending radiologists. 1324 consecutive CT head exams ordered by the ER were interpreted by radiology residents. They reported whether the case was normal or abnormal, noted the relevant findings, and reported their decision confidence using a 6-point scale. Attending neuroradiologists subsequently interpreted the exams. The exams were grouped into 3 categories based on correlation of readings: agree, disagree-insignificant, disagree-significant. There was 91% agreement between resident and attending diagnoses, 7% disagree-insignificant and 2% disagree- significant. Disagreements occurred more often on abnormal than normal cases. Disagreements occurred more often with 1st and 2nd year residents than with 3rd and 4th. Resident confidence was highest for 3rd years, followed by 4th, 2nd and 1st. The less confident a resident was in their diagnosis, the more likely a disagreement occurred. Cases in which a resident expresses a low level of confidence should be carefully checked by the attending since these cases were more often associated with a disagreement than those with high confidence.