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Objective: Contrast material often extends from the radiocarpal joint into the proximal soft tissues adjacent to the ulnar aspect of the ulnar styloid during single-compartment radiocarpal joint MR arthrography of the wrist. The hypothesis of this study was that this is a common finding unrelated to symptoms or examination technique., Materials and Methods: Wrist MR arthrograms were retrospectively reviewed in consensus by two radiologists. The presence or absence of ulnar-sided contrast extravasation was documented, whether this extravasation appeared contained or dispersed, as was the overall degree of proximal extension of the extravasated contrast material. Patient age, sex, wrist sidedness, volume of contrast material administered, location of symptoms reported clinically, and aberrant contrast material also apparent within the midcarpal space or distal radioulnar joint on the MR images reviewed were documented to determine potential association with ulnar-sided contrast extravasation., Results: Ninety-nine examinations met the inclusion criteria. Ulnar-sided contrast extravasation after single-compartment radiocarpal joint injection was present in 56 of the 99 wrists (57%). This finding was statistically more common in right versus left wrists. No other statistically significant associations were identified., Conclusion: Contrast extravasation along the ulnar aspect of the distal ulna after single-compartment radiocarpal joint injection is common. In this study it had no statistically significant association with the location of a patient's wrist pain or abnormal findings evaluated at MR arthrography.

Objective: One of the most important jobs of a radiologist is to pick the most appropriate imaging test for a particular clinical situation. Making a proper selection sometimes requires statistical analysis. The objective of this article is to introduce a simple graphic technique, an ROC plot that has been divided into zones of mostly bad imaging efficacy (ZOMBIE, hereafter referred to as the "zombie plot"), that transforms information about imaging efficacy from the numeric domain into the visual domain., Conclusion: The numeric rationale for the use of zombie plots is given, as are several examples of the clinical use of these plots. Two online calculators are described that simplify the process of producing a zombie plot.

Objective: Sitting can be dangerous to one's health, and radiology tends to be a sedentary profession., Conclusion: By adding a mixture of technological and behavioral changes to our workplaces, we can put a large dent in the amount of sedentary time we spend at work.

Objective: The purpose of this article is to review the most common data analysis methods encountered in radiology-based studies. Initially, description of variable types and their corresponding summary measures are provided; subsequent discussion focuses on comparison of these summary measures between groups, with a particular emphasis on regression analysis., Conclusion: Knowledge of statistical applications is critical for radiologists to accurately evaluate the current literature and to conduct scientifically rigorous studies. Misapplication of statistical methods can lead to inappropriate conclusions and clinical recommendations.

Objective: The purpose of this study was to retrospectively determine whether the ratio of fetal lung-to-liver signal intensities at single-shot fast spin-echo MRI is associated with fetal gestational age., Materials and Methods: All fetal MRI examinations over a 4-year period were reviewed. All MRI examinations were performed with a 1.5-T magnet for indications other than lung maturity. Only examinations performed with a single-shot fast spin-echo sequence of the fetal chest and abdomen were included in the study. Images from a total of 82 fetal MRI examinations were evaluated. Gestational age ranged from 20 weeks to 39 weeks 3 days. Two board-certified subspecialty-trained radiologists with 11 and 17 years of experience blinded to estimated gestational age (EGA) reviewed the images independently. The regions of interest (ROIs) of the fetal lung and liver were drawn in the same plane and on the same image in each case. Fetal EGA was determined either by first-trimester ultrasound when available or by last menstrual period. Linear regression analysis was used to analyze the relation between the lung-to-liver signal-intensity ratio (LLSIR) in the ROIs and fetal EGA for both readers. The association between the LLSIRs estimated by the two readers was assessed by Bland-Altman plot., Results: Summary statistics for LLSIR showed a median value of 2.29 for reader 1 and 2.21 for reader 2. The mean value for reader 1 was 2.4 and for reader 2 was 2.5. The Pearson correlation coefficients between the LLSIR and EGA variables were 0.44 for reader 1 and 0.45 for reader 2. Linear regression analysis showed a statistically significant association between LLSIR and EGA for both readers (p < 0.0004). This ratio increased in a linear manner as EGA progressed., Conclusion: Fetal LLSIR at single-shot fast spin-echo MRI is associated with fetal gestational age.

Objective: Although much attention is paid to the scapholunate ligament, lunotriquetral ligament, and the triangular fibrocartilage complex, additional intrinsic and extrinsic ligaments in the wrist play an important part in carpal stability. With improved MRI techniques, the radiologist can increasingly visualize these ligaments., Conclusion: The anatomy, MRI appearance, and clinical significance of the scapholunate ligament, lunotriquetral ligament, triangular fibrocartilage complex, carpal metacarpal ligaments, and volar and dorsal extrinsic ligaments are reviewed.

Objective: The purpose of this review is to summarize applications (apps) for hand-held computing devices that can be essential aids to radiologists., Conclusion: Numerous apps are relevant to radiologists. Although the author prefers Apple iPad and iPhone apps, similar Android apps fill many of the same software niches.

Objective: The objective of our study was to assess whether high-fidelity simulation-based training is more effective than traditional didactic lecture to train radiology residents in the management of contrast reactions., Subjects and Methods: This was a prospective study of 44 radiology residents randomized into a simulation group versus a lecture group. All residents attended a contrast reaction didactic lecture. Four months later, baseline knowledge was assessed with a written test, which we refer to as the "pretest." After the pretest, the 21 residents in the lecture group attended a repeat didactic lecture and the 23 residents in the simulation group underwent high-fidelity simulation-based training with five contrast reaction scenarios. Next, all residents took a second written test, which we refer to as the "posttest." Two months after the posttest, both groups took a third written test, which we refer to as the "delayed posttest," and underwent performance testing with a high-fidelity severe contrast reaction scenario graded on predefined critical actions., Results: There was no statistically significant difference between the simulation and lecture group pretest, immediate posttest, or delayed posttest scores. The simulation group performed better than the lecture group on the severe contrast reaction simulation scenario (p = 0.001). The simulation group reported improved comfort in identifying and managing contrast reactions and administering medications after the simulation training (p ≤ 0.04) and was more comfortable than the control group (p = 0.03), which reported no change in comfort level after the repeat didactic lecture., Conclusion: When compared with didactic lecture, high-fidelity simulation-based training of contrast reaction management shows equal results on written test scores but improved performance during a high-fidelity severe contrast reaction simulation scenario.

The educational objectives for this self-assessment module are for the participant to exercise, self-assess, and improve his or her understanding of the clinical and imaging features of necrotizing fasciitis and the role of imaging in the clinical management of patients with necrotizing fasciitis.

Objective: This study was performed to determine whether the number of invitations extended to American Journal of Roentgenology (AJR) reviewers is biased toward reviewers with last names that start with early letters of the alphabet., Materials and Methods: The data for this study were extracted from the database of Editorial Manager, the Web-based software used by AJR to manage peer review and other stages of journal production. The alphabetic distribution of last names was extracted from the list of all AJR reviewers in the system between February 1, 2007, and September 13, 2007. The number of reviewer invitations extended to each letter of the alphabet was extracted for the same time period. These data were analyzed using R, a software environment for statistical computing and graphics., Results: During the 224-day sample period, 1,195 manuscripts were submitted to AJR, and 5,825 invitations were sent to reviewers selected from a pool of 1,573. A linear association was noted between the number of review invitations and the alphabetic position of the first letter of the reviewers' last names, with a downward trend from A to Z (r = -0.75). The observed and expected alphabetic distributions of reviewer invitations were statistically significantly different (chi-square goodness-of-fit test, p < 2.2 x 10(-16)). A reviewer whose last name started with A received a mean of 5.49 invitations during the study period, whereas a reviewer whose last name started with S received a mean of 2.90 invitations. Extrapolating these data to 1 year yields 8.9 and 4.7 invitations to review per year for A and S, respectively--a difference of 4.2 invitations per year., Conclusion: During the study period, there is clear evidence of bias toward reviewers whose last names begin with a letter at the beginning of the alphabet. This bias is both statistically and clinically significant, with reviewers with names starting with letters at the beginning of the alphabet invited to review almost twice as often as those with names starting with letters toward the end of the alphabet. This bias is most likely due to "satisfaction of search" by the assigning editors who tend to invite the first panel of reviewers who meet their criteria on a list of names presented to them in alphabetic order. Reviewers' good will can be enhanced if particular alphabetic groups are not overloaded with reviews. Journal editors can help to avoid this bias by consciously spreading review invitations evenly throughout the whole alphabet. Redesign of editorial workflow software could help to avoid this alphabetic bias.

Objective: This study was designed to test our hypothesis that football players with shoulder pain, shoulder instability, or both requiring MR arthrography for evaluation are at an increased likelihood relative to non-football players for having a tear of the posterior glenoid labrum., Conclusion: We conclude that posterior glenoid labrum tears are more prevalent in football players than in non-football players.

Objective: We discuss the case of a 20-year-old woman who presented with a bone mass in the anterior aspect of the distal femur. Radiographs and CT showed a predominantly mature bony mass on the surface of the cortex with a smaller, less mineralized soft-tissue component. MRI showed hyperintensity in the soft-tissue component on T2-weighted images and contrast enhancement following gadolinium infusion. The final pathologic diagnosis was parosteal osteosarcoma., Conclusion: A wide variety of unusual, benign bone lesions that often have little clinical significance have been described in the literature. It is important to distinguish lesions that require specific therapy from those that do not; it is much less important to try to obtain a specific imaging diagnosis for lesions that do not require therapy.

Objective: In this article, we describe a user-friendly Web-based interface that allows review of images combined with integrated data collection and entry for use at multiple sites involved in a large multicenter research project., Conclusion: The Web-based system that we present uses a commercially available Internet browser and Web platform and allows automated data entry that can be easily uploaded into standard data analysis programs. The system simplifies the complex logistics of using multiple sites and reviewers for radiology research and can preserve human subject confidentiality. We tested the system using a large-scale multicenter cohort study of pelvic fracture-related hemorrhage (the "Evaluating Pelvic Hemorrhage" study). Program testing revealed seamless remote image interpretation and data acquisition.

Objective: This study was designed to assess the usefulness of liver window settings when performing abdominal CT for the detection and characterization of hepatic and splenic injuries., Subjects and Methods: We prospectively evaluated helical abdominal CT scans for hepatic and splenic injuries in 300 consecutive patients with blunt abdominal trauma over a 4-month period. There were 204 males and 96 females with a mean age of 34 years (age range, 1-87 years). For each patient, initial CT diagnosis of hepatic or splenic injury was made from images obtained with standard abdominal window settings. CT scans were then immediately reinterpreted using additional images obtained at narrow window width (liver windows). Changes in conspicuity and characterization of injury were recorded. All CT examinations were performed with helical 7-mm collimation at a pitch of 1.5 after oral ingestion of diluted barium and during bolus IV administration of 125 mL of ioversol at a rate of 2-3 mL/sec., Results: We detected hepatic or splenic injuries in 34 patients (11.3%). There were 19 hepatic injuries and 18 splenic injuries. Three patients had injuries to both liver and spleen. Conspicuity of hepatic or splenic injuries was mildly increased (+1 H) on liver windows in 16 patients, whereas the injury was equally conspicuous on both liver window and standard window images in 19 cases. In no case did review of the liver windows result in a change in grade of injury or reveal an injury that was not seen on standard abdominal window images. The total increased cost for printing liver windows was $5748., Conclusion: Routine use of liver window settings for abdominal CT in trauma patients has little clinical usefulness and is not cost-effective.

Objective: On-line continuing medical education (CME) courses offer at least two potential advantages: They are extremely convenient and relatively inexpensive. Before expanding our department's 2-year-old on-line category 1 accredited CME program, we conducted a survey to assess the need for more courses of this type and to document those topics of most interest to our responders., Materials and Methods: An on-line survey form was designed and linked to the home page of our departmental Web server. The 8-month survey asked whether responders were interested in earning category 1 CME hours, how many hours they desired, how much they were willing to pay for each hour, and which topics would interest them most. Responders were also asked to specify their medical practice and medical specialty. All responses were tabulated, and simple descriptive statistics were calculated., Results: Our survey received 317 responses: 188 from physicians, 42 from radiology technologists, 11 from physician assistants and nurse practitioners, and the remainder from 26 other categories of practice. Physician specialties identified included 86 diagnostic radiologists, 24 internists, 18 emergency medicine specialists, 15 family practitioners, and 45 from 14 other specialties. Responses came mainly from the United States; however, 32 responses were received from 15 other countries. The median number of on-line CME hours desired was 15 (range, 1-1324). Physician responders were willing to pay a median amount of $10 per credit hour (range, $0-400). The most commonly suggested topic was general radiology, followed by general reviews of MR imaging, CT, sonography, and various organ-based specialties in radiology such as mammography, neuroradiology, and musculoskeletal radiology., Conclusion: Physicians and many other health care workers are interested in on-line CME and are willing to pay for such a service. This information, as well as the suggested topics collected in this survey, may prove helpful in planning future offerings of on-line CME.

Objective: Radiology departments have traditionally used film-based collections of interesting cases for teaching purposes. Film-based files are expensive to create and duplicate, and they physically occupy considerable space. As one solution to these problems, our department created an on-line radiology teaching file in digital format., Materials and Methods: Our teaching file resides on a Macintosh Quadra 700 computer that is connected to the Internet, a worldwide network of interconnected computers, via our campus Ethernet network. Our digital teaching file images and text are composed in HyperText Markup Language (HTML) and are made available to the world with Webserver software known as MacHTTP. These teaching files are accessed using World-Wide Web (WWW) client software such as Mosaic, MacWeb, or Netscape., Results: Our digital teaching file is available at no charge to anyone in the world with access to the Internet and WWW client software. Our radiology residents can access this file via several workstations in our department. Mosaic is an easy-to-use interface, and the use of our digital teaching file has increased significantly. In the 3 months since its creation, our teaching file has been accessed not only by our radiology residents but also by hundreds of other users in 33 countries., Conclusion: Use of Mosaic and the WWW format has resulted in an easy-to-use hypertext interface to the Internet, which allows even persons with little computer experience to navigate through the Internet, read text files, view images (stills and movies), and download files by merely pointing with the mouse and clicking on items of interest. This has allowed us to maintain a central teaching file that is physically small and easy to share with all the hospitals in our system. We invite the worldwide radiology community to access these files and to submit cases from their own teaching files to share with the rest of the world.

Objective: We set out to determine whether specific findings can be seen on chest radiographs of adult patients with cystic fibrosis who are having acute exacerbation of respiratory disease., Materials and Methods: Over a 2-year period, 22 adults with cystic fibrosis had both a baseline chest radiograph and a radiograph obtained either because of acute exacerbation or for some other reason (nonexacerbation). Fourteen radiographic features, including mucous plugs, air-space disease, peribronchial thickening, bronchiectasis, fluid levels, and lymphadenopathy, were scored retrospectively by two radiologists, who did not have knowledge of the patient's clinical condition, as being present, absent, increased, decreased, or unchanged. An overall assessment (better, worse, or no change) was also given for each radiograph. Data were analyzed in two ways (per individual episode and per individual patient) by using contingency tables, with statistical significance determined by exact permutation testing., Results: Of the 22 patients, 13 had 29 exacerbations and eight had 11 nonexacerbations. The remaining patient had radiographs showing both an exacerbation and a nonexacerbation. With the exception of overall change (p = .06), none of the radiographic variables showed a statistically significant association with exacerbation (mean p value, .66; range, .19-.90)., Conclusion: The 14 specific radiographic findings studied, including peribronchial thickening, mucous plugs, air-space disease, and fluid levels, were not useful in determining whether an adult patient with cystic fibrosis was having acute exacerbation of the disease. With regard to these individual variables, chest radiographs are not helpful in the management of acute exacerbation of cystic fibrosis in adults. However, overall change approached statistical significance (p = .06). The value of chest radiography lies more in excluding the rare major complication, such as pneumothorax, than in diagnosing the usual exacerbation.

A chronic need exists for anatomic drawings that are suitable for publication. The best drawings of this type are the result of close collaboration between a trained medical illustrator and the author commissioning the artwork. However, high-quality drawings usually command premium prices and are not within everyone's budget. Similarly, services that can provide such illustrations are not available in all areas. This paper describes several methods of producing high-quality anatomic drawings with a personal computer. These drawings can be produced from the digital images obtained on one's local CT or MR scanners, or from digitized slides and photographs. Other images can be scanned from various sources of anatomic line art that are in the public domain. A final source of anatomic drawings is commercially available medical clip art. The drawings created from any of these sources can be modified to suit one's needs and can provide very satisfactory results.

Radiologists must consider several factors when asked by a patient to disclose the results of a radiologic examination. This study represents a survey of radiologists' and clinicians' opinions regarding disclosure of information to patients by the radiologist. A clearer understanding of the preferences of radiologists and clinicians may serve to improve communication and enhance cooperation between the two groups, with the ultimate result being improved patient care.

Despite a decade and a half of digital imaging in radiology, most radiology teaching files remain film-based. The reasons include the high cost or unavailability of digital acquisition and display devices. In the past few years, a number of excellent exhibits that combine inexpensive microcomputers with radiologic education have been shown at national meetings [1-6]. Unfortunately, many of these methods require esoteric hardware, expensive or proprietary software, or special programming skills. We developed a simple method for creating and disseminating a teaching file of imaging studies obtained with digital techniques.

Seven patients with neuromuscular disorders were examined, including one with cerebral palsy, one with Duchenne muscular dystrophy, two with paraplegia, and three with poliomyelitis; all exhibited skeletal changes mimicking those found in juvenile rheumatoid arthritis and hemophilia. These findings included apparent overgrowth of the epiphyses, periarticular osteoporosis, and joint-space narrowing in seven subjects; accentuation of the trabecular pattern in six; gracile bones and soft-tissue wasting in five; tibiotalar slant in two; and premature epiphyseal closure in one. Changes in osseous vascular dynamics and the debilitation or immobilization found both in patients with neuromuscular disorders and those with arthritis may help explain these overlapping findings. While the clinical distinction between the neuromuscular and arthritic disorders is straightforward, the similarity in radiographic appearance has received little attention. If the clinical history is inadequate, this may result in confusion or misinterpretation by the radiologist. In the absence of more specific findings, such as articular erosions or erosions of the femoral intercondylar notch, the differential diagnosis may be mistakenly limited to juvenile rheumatoid arthritis and hemophilia. In such cases, the neuromuscular disorders should also be considered in the differential diagnosis.

Gallstones from 63 patients were evaluated by in vitro 1.5-T MR imaging, with T1- and T2-weighted images, and in 14 cases, a fat-suppression sequence (short-T1 inversion recovery imaging). Subsequent chemical analysis was performed on 43 gallstones. In vitro proton MR spectroscopy was performed on 14 stones. On T1-weighted MR images, foci of increased signal were seen in 46 of 63 stones (faint in 17, moderate in nine, and bright in 20). T2-weighted images showed areas of increased signal in 18 of 63 stones (faint in 15, moderate in three). T1-weighted MR imaging patterns were homogeneously dark (17), homogeneously bright (two), homogeneously faint (three), rimmed (dark rim and bright center, 32), and laminated (nine). Short-T1 inversion recovery imaging suppressed the foci of increased signal in 13 of 14 cases. Despite imaging characteristics suggestive of high lipid content, spectroscopy revealed only a single peak corresponding to a large water-proton signal. The T1 relaxation times of the water were shortened, ranging from 0.006 to 0.92 sec, explaining the increased signal seen on MR images of the gallstones. MR imaging characteristics (signal intensity, relative signal area, or imaging patterns) did not correlate with chemical composition. We hypothesize that different structural relationships must exist within gallstones of similar chemical content that alter the water bonding and hence the MR imaging characteristics.

We evaluated the ability of high-resolution, real-time sonography to identify and characterize artificially produced lesions in the menisci in human cadaveric knee specimens. In total, 20 lesions created in 10 specimens from five knees were prepared and examined sonographically. Four different types of lesions were created: eight vertical concentric tears, four horizontal tears, four vertical radial tears, and four complex lesions including displaced or amputated meniscal edges. All 20 (100%) of the lesions were visualized sonographically. The vertical concentric tears were the easiest to locate and identify, and appeared as highly echogenic lines in the menisci. Tears of this type as small as 2 mm could be visualized. The vertical radial tears were the most difficult to visualize, and no lesions of this type smaller than 5 mm could be seen. Our study shows that under optimal experimental conditions, sonography is capable of reliably demonstrating even small meniscal tears. On this basis, we believe that further clinical studies of the efficacy of meniscal sonography are both reasonable and necessary.

We compared coronal, large-field-of-view, body-coil MR images with sagittal, small-field-of-view, surface-coil images of 30 hips for their sensitivities in establishing the diagnosis of avascular necrosis; spatially localizing the avascular necrosis; and detecting joint-space narrowing, femoral head collapse, articular cartilage fracture, and joint fluid. We also compared the two separate plane/coil combinations for detection of the "double-line" sign (high signal inside a band of low signal, believed to be characteristic for avascular necrosis) and intertrochanteric conversion of hematopoietic marrow to fatty marrow. Coronal, large-field-of-view, body-coil images provided an adequate screening examination for the presence of avascular necrosis (sensitivity of 94%) and were preferred in all cases for mediolateral localization of focal abnormality. They were also better for assessing joint fluid and detecting fatty conversion of marrow. Sagittal, small-field-of-view, surface-coil images were preferred for anteroposterior localization in all cases and for superoinferior localization of focal abnormality in 15 of 18 cases. They detected additional cases of joint-space narrowing, articular cartilage fracture, and the double-line sign missed by coronal, body-coil images. Sagittal, small-field-of-view, surface-coil images are a valuable adjunct to MR evaluation of femoral avascular necrosis because they provide additional information that may be useful for planning surgical therapy.

Forty-nine patients with cervical spine fractures were identified among 160 patients who underwent CT of the cervical spine for blunt trauma. Although there was a high index of suspicion on the plain film interpretation, as well as a large percentage of false positives, many fractures were found on CT that were not suggested, even in retrospect, on the plain radiographs. Of the 136 fractures ultimately identified in these patients, CT detected 135 (99%) while only 64 (47%) were seen or suspected on the initial screening radiographs. At first glance, this might appear to discredit the plain films as a screening device. However, most of these "occult" fractures occurred in vertebrae that had been identified as probably fractured in other parts, for example, pedicle fractures found in vertebrae initially suspected of harboring only a vertebral body fracture. Most of the remainder of the uncovered fractures were in vertebrae immediately adjacent to ones that were initially identified as fractured. Indeed, of the 49 patients with fractures, only one had an adequately exposed and positioned plain film that was completely normal. The ability of CT to determine quickly and confidently the presence or absence of cervical fractures and to define the position of fragments in relation to the spinal canal is of considerable value in the medical and nursing management of the seriously traumatized patient. For example, when a fracture is seen or suspected on conventional films, a limited CT examination of the area is recommended. Plain films should be used to guide the CT examination so that an intact vertebra above and below the lesion is included. If an adequately exposed and positioned plain film series of the cervical spine is normal, it is unlikely that CT will reveal a fracture. While conventional radiographs fail to detect a surprising number of fractures, they retain their value as a screening tool and as a guide to selective CT imaging.

We retrospectively reviewed the 99mTc-diphosphonate scans of 980 patients with Hodgkin or non-Hodgkin lymphoma to define the typical appearance and distribution of skeletal lesions. The results were compared with the presence of skeletal symptoms and the findings on 67Ga-citrate scintigraphy, when available. Forty (4%) of the 980 patients had 77 scintigrams showing osseous involvement; there was an average of 3.5 lesions per study. Compared with patients with non-Hodgkin lymphoma, patients with Hodgkin disease had significantly fewer axial lesions (44% vs 82%, p less than .000001, two-tailed test) and more frequent involvement of the extremities. Subtle lesions were common. Of the lesions detected by scintigraphy, significantly more were detected by 99mTc-diphosphonate imaging (95%) than were detected by 67Ga-citrate (44%) (p less than .00001, two-tailed test), and most of these were far less apparent on the 67Ga-citrate study. Skeletal pain was an insensitive but specific indicator of skeletal disease. These results show that skeletal scintigraphy in patients with lymphoma typically reveals multiple subtle and asymptomatic lesions with frequent extremity involvement. Diffusely increased calvarial activity is commonly seen and often persists in proved remission. Increased juxtaarticular activity is specific for malignant skeletal involvement.