Imaging characteristics of diffuse idiopathic skeletal hyperostosis with an emphasis on acute spinal fractures: review.

OBJECTIVE: The educational objectives of this self-assessment module are for the participant to exercise, self-assess, and improve his or her understanding of the imaging of diffuse idiopathic skeletal hyperostosis (DISH), with emphasis on acute spinal fractures. CONCLUSION: Understanding the pathomechanics of the fractures in the ankylosed spine is important in the differentiation of the acute spinal fractures in DISH and ankylosing spondylitis. This article emphasizes the imaging features of spinal DISH and acute spinal fractures in DISH, distinguishing them specifically from those in ankylosing spondylitis.

Imaging characteristics of diffuse idiopathic skeletal hyperostosis with an emphasis on acute spinal fractures: 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 of diffuse idiopathic skeletal hyperostosis (DISH).

Diffusion tensor imaging in Niemann-Pick Type C disease.

Niemann-Pick Type C disease is a homozygous recessive disorder resulting in errant intracellular cholesterol metabolism and the accumulation of intracellular unesterified cholesterol and sphingolipids. Although no current effective treatment exists for Niemann-Pick Type C disease, a number of therapies are under development in animal models. As therapies are brought into clinical trials, it will be extremely helpful to have a reliable means to track the progression of the disease and to monitor its response to therapy. In this effort, diffusion tensor imaging has been applied to investigate the white matter in a Niemann-Pick Type C patient, and the results compared to those from age-matched control subjects. Diffusion tensor imaging enables quantitative measurement of water diffusion in white matter, which is sensitive to the architecture and integrity of the tissue. Compared with control subjects, significant reductions in fractional anisotropy values were observed in regions of white matter, most prominently in the corpus callosum. The results from this case study suggest that diffusion tensor imaging may allow progression of the disease to be quantitatively measured and may be able to play a role as a surrogate marker in clinical trials.

Evaluation of emergency CT scans of the head: is there a community standard?

OBJECTIVE: This study was designed to assess the accuracy of general radiologists in the interpretation via teleradiology of emergency CT scans of the head. MATERIALS AND METHODS: We studied the interpretations of 716 consecutive emergency CT scans of the head by a group of 15 board-certified general radiologists practicing in the community (as opposed to an academic setting). The scans were sent via teleradiology, and the preliminary interpretations were made. Three of the general radiologists were functioning as nighthawks, and the remaining 12 were acting as on-call radiologists in addition to their normal daytime duties. Each CT examination was interpreted by one of five neuroradiologists the day after the initial interpretation had been performed. The findings of the final interpretation and the preliminary interpretation were categorized as showing agreement, insignificant disagreement, or significant disagreement. The reports in the two categories indicating disagreement were reviewed and reclassified by a consensus of three university-based neuroradiologists. RESULTS: Agreement between the initial interpretation by the general radiologist and the final interpretation by the neuroradiologist was found in 95% of the CT scans. The interpretations were judged to show insignificant disagreement in 3% (23/716) of the scans and to show significant disagreement in 2% (16/716). Of the 16 significant errors, five were false-positive findings and 11 were false-negative findings. Forty-seven CT scans depicted significant or active disease, and in 11 (23%) of these scans, the final report differed significantly from the preliminary interpretation. Three patients had pituitary masses, none of which had been described on the preliminary interpretation. CONCLUSION: The rate of significant discordance between board-certified on-call general radiologists and neuroradiologists in the interpretation of emergency CT scans was 2%, which was comparable to previously published reports of residents' performance. The pituitary gland may be a blind spot, and additional attention should be focused on this area.

Radiology resident evaluation of head CT scan orders in the emergency department.

BACKGROUND AND PURPOSE: Prior studies have revealed little difference in residents' abilities to interpret cranial CT scans. The purpose of this study was to assess the performance of radiology residents at different levels of training in the interpretation of emergency head CT images. METHODS: Radiology residents prospectively interpreted 1324 consecutive head CT scans ordered in the emergency department at the University of Arizona Health Science Center. The residents completed a preliminary interpretation form that included their interpretation and confidence in that interpretation. One of five neuroradiologists with a Certificate of Added Qualification subsequently interpreted the images and classified their assessment of the residents' interpretations as follows: "agree," "disagree-insignificant," or "disagree-significant." The data were analyzed by using analysis-of-variance or chi-squared methods. RESULTS: Overall, the agreement rate was 91%; the insignificant disagreement rate, 7%; and the significant disagreement rate, 2%. The level of training had a significant (P =.032) effect on the rate of agreement; upper-level residents had higher rates of agreement than those of more junior residents. There were 62 false-negative findings. The most commonly missed findings were fractures (n = 18) and chronic ischemic foci (n = 12). The most common false-positive interpretations involved 10 suspected intracranial hemorrhages and suspected fractures. CONCLUSION: The level of resident training has a significant effect on the rate of disagreement between the preliminary interpretations of emergency cranial CT scans by residents and the final interpretations by neuroradiologists. Efforts to reduce residents' errors should focus on the identification of fractures and signs of chronic ischemic change.