The value of dynamic MRI studies in parotid tumors.

RATIONALE AND OBJECTIVES: To evaluate the ability of dynamic contrast-enhanced magnetic resonance imaging (MRI) to differentiate several tumor entities of the parotid gland in a prospective clinical trial. MATERIALS AND METHODS: A total of 112 patients with parotid tumors were examined with dynamic contrast-enhanced 1.5 T MRI. Precontrast axial T1-weighted imaging was used to select five slices for the dynamic study. Subsequently, a T1-weighted FLASH sequence was used for the dynamic contrast study (0.2 ml Gd/kg x body weight). Contrast agent application and the FLASH sequence were started simultaneously. Ten acquisitions of 10 seconds' scan time each were performed (total acquisition time 1:40 minutes). Signal intensity versus time (SIvT) curves was obtained for all tumors. After correlation of the categorized SIvT curves, these were compared with histopathology. Finally, all MRIs together with the tumor specific SIvT curves were re-read and correlated with histopathologic diagnosis. All reading sessions were done by three experienced radiologists. RESULTS: Four characteristic intensity-time curves were observed: pleomorphic adenoma showed a gradual increase in signal intensity, followed by a plateau phase on a low intensity level. Cysts showed a vacillating course at a low signal intensity level. Adenolymphomas as well as carcinomas showed a rapid increase in signal intensity followed by a plateau phase. Statistic significance was found for the time-to-peak values for adenolymphomas and pleomorphic adenomas and for the maximum peak signal intensity values for carcinomas. Together with other morphologic MRI criteria (contrast enhancement, border characteristics) and clinical features, a differentiation between adenolymphoma and carcinoma was possible. CONCLUSIONS: With additional dynamic contrast-enhanced MRI, a more reliable differentiation between common parotid tumors is possible before surgery.

Modes of information delivery in radiologic anatomy education: Impact on student performance.

RATIONALE AND OBJECTIVES: This study provides a systematic assessment of different methods of delivering radiologic teaching content (lecture, printed text, and digital content delivery) under standard conditions, enabling comparison of the effectiveness of these methods. MATERIALS AND METHODS: A printed atlas of sectional anatomy was used as a standard. Digital content was developed on the basis of the printed atlas. Lecturers used both the printed and the digital content to prepare lectures. Standardized teaching material thus created was presented to second-term undergraduate students who had attended the school's anatomy course, but had not received any radiology teaching. Multiple choice examinations were used to assess the students' ability to recognize anatomical structures in known as well as unknown images. In a survey, the students' subjective experience of the learning process was assessed. RESULTS: No difference was seen between the groups regarding examination results. Students preferred a combination of digital media and lectures by enthusiastic teachers. CONCLUSIONS: The shortage of teachers requires a compromise concerning the delivery of radiologic anatomy content in a medical school setting. Based on our results, we recommend a combined approach of lecture and digital content delivery.

www.tnt-radiology.de: Teach and be taught radiology: implementation of a web-based training program based on user preferences as determined by survery.

RATIONALE AND OBJECTIVES: To create a Web-based training program addressing the needs of a large, heterogeneous audience of users. MATERIALS AND METHODS: We defined our target group as consisting of medical professionals who teach radiology, or who, by their own perception, would benefit from improving their radiologic image interpretation skills. We interviewed 483 members of this group, eliciting their preferences with regard to layout, interactivity, contents, and other categories (11 in total). Considering majority preferences as recommendations and using the help of a special interest group of medical students, we assembled 500 teaching cases over a 1-year period into an interactive training program and made it available on the World Wide Web. RESULTS: Important preferences expressed by majorities of interviewees were: high levels of interactivity, clear layout, intuitive usability, short page load times, permissibility of saving content locally, cost-free access, consideration of user input in the site development. To our knowledge, our web program TNT-Radiology, accessible at , is the first to implement all of these recommendations simultaneously. CONCLUSIONS: We have created a Web-based program usable for teaching and learning radiologic image interpretation that meets the needs of a heterogeneous target audience to an unprecedented extent.

COMPARE/Radiology, an interactive Web-based radiology teaching program evaluation of user response.

RATIONALE AND OBJECTIVES: The aim of this study is to assess user benefits of COMPARE/Radiology, a highly interactive World Wide Web-based training program for radiology, as perceived by its users. MATERIALS AND METHODS: COMPARE/Radiology (http://www.idr.med.uni-erlangen.de/compare.htm), an interactive training program based on 244 teaching cases, was created by the authors and made publicly available on the Internet. An anonymous survey was conducted among users to investigate the composition of the program's user base and assess the acceptance of the training program. In parallel, Web access data were collected and analyzed using descriptive statistics. RESULTS: The group of responding users (n = 1370) consisted of 201 preclinical medical students (14.7%), 314 clinical medical students (22.9%), 359 residents in radiology (26.2%), and 205 users of other professions (14.9%). A majority of respondents (1230; 89%) rated the interactivity of COMPARE/Radiology as good or excellent. Many respondents use COMPARE/Radiology for self-study (971; 70%) and for teaching others (600; 43%). Web access statistics show an increase in number of site visits from 1248 in December 2002 to 4651 in April 2004. CONCLUSION: Users appreciate the benefits of COMPARE/Radiology. The interactive instructional design was rated positively by responding users. The popularity of the site is growing, evidenced by the number of network accesses during the observation period.

ELERA: a WWW application for evaluating and developing radiologic skills and knowledge.

RATIONALE AND OBJECTIVES: To provide an online facility for evaluating, comparing, and building expertise in radiologic anatomy and clinical radiology. MATERIALS AND METHODS: Project participants were recruited from an experienced special interest group of students at the local medical school. A rigid protocol was agreed upon, defining and assigning the tasks of case selection, data entry, test task creation, and peer review. The presentation of test tasks and evaluation of user input was implemented as a custom web application. RESULTS: ELERA, an online assessment and learning resource based on 1,650 pathologic cases and 550 anatomy cases, was created and made publicly accessible as a world wide web application. CONCLUSION: The project design facilitated the creation of a free, highly accessible and user-friendly resource that offers capabilities for individual longitudinal and intersubject comparative assessment.

COMPARE radiology: creating an interactive Web-based training program for radiology with multimedia authoring software.

RATIONALE AND OBJECTIVES: Computer-based training has two primary benefits: Content can be presented interactively, and students can choose the time, place, and pace of learning. As a subject of medical education, radiology lends itself particularly well to computer-based training because of its highly visual content. To improve the efficiency of radiology training at their institution, the authors decided to create an interactive Web-based training site. MATERIALS AND METHODS: Working with a group of medical students knowledgeable in multimedia authoring, the authors used authoring software to create "COMPARE Radiology," an interactive training program that follows the modality-based structure of the undergraduate curriculum for radiology at the University of Erlangen-Nuremberg, Erlangen, Germany, and at medical schools worldwide. RESULTS: The Web-based program offers cases and exercises in radiographic anatomy at different selectable levels of difficulty, allowing users to test and build their knowledge of radiology. Pathologic images are initially presented without any further information. Additional information (patient history, laboratory results, reports from other imaging studies, and normal images for comparison) can be retrieved selectively and successively. Further information regarding the diagnosis and pathologic findings can be found by following links to external Web sites. The COMPARE Radiology program content is extended and updated regularly. The program is subject to internal peer review and can be evaluated by the user online. CONCLUSION: The authors' experience shows that a highly interactive Web-based training program for radiology, tailored to the requirements of the target group, can be developed economically by a team of medical students using an advanced storing system, with the guidance of a radiologist and without the help of professionally trained computer experts.