PubMed Health⌕ Search

Biomedical subjects

Felix S Chew

Publications and source records attributed to Felix S Chew.

At least 19 recordsLinked to original sources

Radiological reasoning: incidentally discovered liver mass.

OBJECTIVE: A 49-year-old woman presented to the emergency department after a fall in which she sustained a right subcapital hip fracture. During her hospital stay she developed abdominal pain, and a hypoechoic liver mass was found on sonography. Multiphase CT showed a hepatic mass with brisk arterial phase enhancement, rapid washout on the portal venous phase, and delayed phase hypodensity. The final pathology diagnosis was hepatocellular carcinoma. CONCLUSION: Incidental lesions are frequently discovered during routine radiographic evaluations. Correlation with clinical history and additional confirmatory imaging is essential for appropriate diagnosis and management.

Abdomen, Acute↗

Imaging of pulmonary embolism: self-assessment module.

The educational objectives for this self-assessment module on imaging of pulmonary embolism are for the participant to exercise, self-assess, and improve his or her understanding of the evaluation of patients with suspected pulmonary embolism using CT angiography; gain familiarity with nonembolic conditions that may be found in patients who are studied with CT angiography for suspected pulmonary embolism; and gain familiarity with the phenomenon of paradoxical embolism, its manifestations on CT angiography, and its radiologic differential diagnosis.

Angiography↗

Imaging of the pineal region and spine: self-assessment module.

The educational objectives for this self-assessment module on imaging of the pineal region and spine are for the participant to exercise, self-assess, and improve his or her understanding of the evaluation of patients with brain tumors, particularly solid masses of the pineal region; gain familiarity with the clinical entity of chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) and its radiologic appearance; and gain familiarity with the clinical entity of spinal dural arteriovenous fistula (DAVF) and its radiologic appearance.

Brain Neoplasms↗

Spreadsheet application for radiology resident match rank list.

RATIONALE AND OBJECTIVE: Enormous resources are spent on the selection process for radiology residency, yet agreement on criteria, process, and outcome remains elusive. The aim was to develop, implement, and evaluate a spreadsheet application that streamlined the creation of a match list for resident selection. MATERIALS AND METHODS: The Department of Radiology's traditional procedure of screening, interviewing, and rating candidates was left intact because the selection committee could not reach consensus regarding possible improvements in the process or outcome measures. We developed a spreadsheet application that used the ratings of candidate desirability for our program from our preexisting process to create a tentative match list by adding a system of ordinal ranking and weighting. After 4 years of use, the fairness and usefulness of this application were evaluated by members of the selection committee by means of a survey. RESULTS: The spreadsheet application was used to create tentative match lists for 4 years. The system eliminated ties among candidates on the preliminary match list and met the expectations of a majority of the selection committee members for fairness, objectivity, efficiency, and results. CONCLUSION: A spreadsheet application can streamline the process of resident selection without having to resolve underlying conflicts about selection criteria and outcome measures.

Attitude of Health Personnel↗

Application of the case method in medical student radiology education.

RATIONALE AND OBJECTIVES: Our goal is to design, implement, and evaluate a rich educational activity to engage medical students in learning the importance of providing clinical histories when ordering radiological examinations. We adapted the format of the case method commonly used in business schools. MATERIALS AND METHODS: In the setting of a 1-week required radiology course offered during the third year of medical school, we created an unknown case assignment consisting of two chest radiographs and a concise history for three- to four-person study teams. Unknown to students, each team received the same images, but different patient histories. After turning in their written analyses, students had a classroom opportunity to discuss their conclusions. A written evaluation of the entire experience using both Likert items and unstructured response items was conducted at the end of each session. RESULTS: The evaluation was conducted during a 17-month period, and 141 evaluations were received from students. The response rate was 100%. Most teams met several times and worked on the assignment for 2 or 3 hours. Students agreed that the learning experience was worthwhile (95%), content was appropriate (93%), and the activity should be continued for subsequent classes (94%). Unstructured responses indicated that students learned the importance of clinical histories in the interpretation of radiological studies. CONCLUSION: An educational activity based on the case method was well received by students and met its educational objectives. Activities of this type have potential for widespread application in radiology education.

Education, Medical, Undergraduate↗

A compartmental approach to the radiographic evaluation of soft-tissue calcifications.

Musculoskeletal radiology, like most areas of diagnostic radiology, has seen a dramatic increase in the use of cross-sectional imaging techniques over the last decade. However, conventional radiography remains a vital role in the evaluation of disease involving the spine and extremities. Given its widespread availability and low cost, radiography should be the initial examination obtained when imaging is clinically indicated. Therefore it is essential that the practicing radiologists be able to maximize the diagnostic value of this common study to aid the clinicians with a focused differential diagnosis, if not a definitive diagnosis. While much emphasis has been placed on radiographic interpretation of osseous lesions, similar diagnostic yield can be often obtained about calcified or ossified soft-tissue lesions. Detailed evaluation of the distribution and morphology of the soft-tissue calcifications, combined with a thorough knowledge of the entities that may occur at the site of the noted abnormality, provides significant interpretive value to provide a definitive diagnosis or accurately recommend the next most effective management step. We provide a compartmental-based approach to the interpretation of soft-tissue calcifications.

Calcinosis↗

Radiology of the hands: review and self-assessment module.

OBJECTIVE: The educational objectives of this continuing medical education activity are for the reader to exercise, self-assess, and improve skills in diagnostic radiology with regard to the interpretation of radiographs, CT, and MRI of the hand and to improve understanding of the appropriate use of CT and MRI in evaluating lesions of the hand. CONCLUSION: The conditions illustrated in this article include erosive osteoarthritis, sarcoidosis, metastatic calcification, and synovial sarcoma. This article is qualified by the American Board of Radiology (ABR) in meeting the criteria for self-assessment toward the purpose of fulfilling requirements in the ABR Maintenance of Certification.

Adult↗

Radiological reasoning: a benign-appearing bone mass.

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.

Adult↗

Radiological reasoning: recurrent right lower quadrant inflammatory mass.

OBJECTIVE: We discuss the case of a 58-year-old woman who presented with right lower quadrant pain and fever. CT showed a right lower quadrant inflammatory mass presumed to be an appendiceal abscess. The patient underwent open drainage of the mass but failed to return for an interval appendectomy. She returned 23 months later with a recurrent right lower quadrant inflammatory mass treated initially with percutaneous drainage followed by interval appendectomy. The final pathologic diagnosis was mucinous cystadenoma with perforation. CONCLUSION: Primary neoplasms of the appendix are uncommon but should be considered in the correct clinical and imaging scenario.

Abscess↗

MR imaging of tendon abnormalities of the elbow.

Tendon injuries about the elbow are among the most commonly encountered pathology in this articulation. These injuries are often the result of chronic repetitive microtrauma but can be seen in the setting of acute trauma. This article focuses on the imaging diagnosis of tendon pathology in the elbow and the associated findings that can be seen with tendon injury. A detailed understanding of common pathology and patterns of injury can facilitate the ease and accuracy of imaging diagnosis.

Humans↗

Imaging, diagnosis, and staging of bone tumors: a primer.

By considering the radiographic appearance in combination with the lesion location and the patient's history, an informed differential diagnosis can be generated for a bone lesion. Primary musculoskeletal malignancies often display aggressive characteristics such as cortical breakthrough, bone destruction, periosteal reaction, and associated soft-tissue masses. On the other hand, benign lesions usually do not have these aggressive features. The matrix mineralization reflects the lesion's underlying pathology and can help to narrow the differential diagnosis.

Biopsy↗

Projected digital radiologic images for teaching: balance of image quality with data size constraints.

RATIONALE AND OBJECTIVES: The authors performed this study to determine, in the context of a teaching presentation with slides, the information content needed in a digitized radiologic image for it to be equivalent in quality to an analog image. MATERIALS AND METHODS: Eleven sets of radiologic images were obtained from a teaching file collection and digitized. The images were scanned at high resolution and saved as image files. The information content of each image was then halved repeatedly with repeat sampling of the image. This procedure was repeated nine times to yield a total of 10 images with an information content that ranged from very low (32 kB) to high (12 MB). Each of these image files was made into a 35-mm slide by using a digital slide maker. The original radiographs were subsequently made into slides by using conventional photographic methods. Care was taken to make the images identical in every respect except digitization and information content. The slides were shown to radiologists, who filled out questionnaires to rate image quality. RESULTS: Digitized slides that contain an average of 416 kB of data (the equivalent of a 750 x 570-pixel matrix with 8-bit gray levels) were equivalent to analog images for 90% of viewers. At 830 kB (1,060 x 800-pixel matrix with 8-bit gray levels), 100% of viewers found no difference between digitized and analog images. CONCLUSION: Digital images become indistinguishable from analog images if a sufficient amount of information is retained in the digital image. There is a defined relationship between the perception of quality and the information content of a digital image.

Image Processing, Computer-Assisted↗

Distributed Web-supported radiology clerkship for the required clinical clerkship year of medical school: development, implementation, and evaluation.

RATIONALE AND OBJECTIVES: The authors performed this study to develop, implement, and evaluate a new radiology clerkship for the required clinical clerkship year of medical school. MATERIALS AND METHODS: A mandatory radiology clerkship experience was added to the required clinical clerkships as a series of 10 independent half-day teaching sessions. These sessions were distributed as one session per existing clerkship throughout the year. To provide continuity and organization, Web-based curriculum materials were designed and implemented as a component of the radiology clerkship. The new clerkship was evaluated with observations, pretest and posttest measures with a control group, structured and unstructured student and faculty surveys, and individual and small group interviews. RESULTS: The clerkship was successfully developed and implemented. Ninety-five students have completed the clerkship. Their mean posttest score (84.8) was significantly higher than their mean pretest score (58.8, P < .001) and the mean control group score (59.7, P < .001). Students rarely used the Web site. Disadvantages of the distributed clerkship were identified. CONCLUSION: A radiology clerkship distributed among existing clerkships is feasible but has many disadvantages. Students greatly prefer live instruction, and Web-based educational materials are more valuable to faculty and administrators than to students.

Attitude↗

Distributed radiology clerkship for the core clinical year of medical school.

OBJECTIVE: The central role that diagnostic radiology has in the modern practice of medicine has not always been reflected in radiology's place in the curriculum. We developed a new radiology clerkship for undergraduate medical students during their core clinical year that was supported by Web technology. The assumptions underlying the design of the clerkship were that radiology is best learned from radiologists and that students are most receptive to learning radiology when it is related to concurrent patient care experiences. DESCRIPTION: Beginning in May 2000, a required radiology clerkship experience was incorporated into the core clinical year at Wake Forest University School of Medicine. The core clinical year was organized into three 16-week blocks of clerkships. Two or four independent half-day radiology tutorial sessions were included with each clerkship block, and attended by all students in the block (approximately 35 students), regardless of their specific clerkship assignments. There were ten different radiology tutorials, each given three times during the year as students rotated through the clerkship blocks. Thus, each student attended a radiology tutorial session every four to eight weeks during the year. The topics covered during the tutorials were correlated with the content of the clerkship blocks and included adult and pediatric chest radiology, adult and pediatric abdominal radiology, body CT, neuroradiology, obstetric ultrasound, gynecologic ultrasound, osteoporosis, adult and pediatric fractures, mammography, and cervical spine trauma. The tutorials included pre- and post-test, lectures, case presentations, and sometimes tours of the radiology department. The educational emphasis was on pragmatic case-based learning exercises, development of verbal and visual vocabulary, and learning when and where to seek more information. To provide continuity and organization, Web-based curriculum materials were designed and implemented as a component of the clerkship. The home page of the Web site provided the schedule, faculty names, attendance and grading policies, course overview, and links to individual tutorials. The pages for individual tutorials included educational objectives, glossary of radiology terminology relevant to the subject, lecture slides and handouts, and teaching cases. All students had laptop computers and access to the academic network, but did not use them during the actual tutorial sessions. DISCUSSION: Implementation of the radiology clerkship required extensive negotiation with directors of other clerkships so that students could be released from their other responsibilities in order to attend the radiology tutorials. The radiology clerkship format has proven to be complex in its administration, with faculty and students on different schedules commuting to the radiology lecture hall from various locations. Extensive use of e-mail and communication via the Web site have been instrumental in reminding faculty and students of upcoming sessions. Preliminary evaluations have indicated that students liked the radiology sessions and learned a great deal, but disliked the scheduling and the lack of continuity. An evaluation of the curriculum and its components is ongoing.

Clinical Clerkship↗