Online self-study of chest X-rays shows no difference between blocked and mixed practice.

CONTEXT: Chest radiograph interpretation is a complex skill and learners may benefit from deliberate instructional design modalities, such as mixed practice. Proposed benefits of mixed over blocked practice include the elimination of cueing and the highlighting of contrasting features. However, current evidence for the superiority of mixed practice is conflicting. OBJECTIVES: This study compares mixed versus blocked practice, after the initial teaching of concepts, among medical students using online self-study chest X-ray (CXR) modules. METHODS: Two online CXR modules were developed that cover identical content but differ in the organisation of practice images. Blocked modules provided practice CXRs after each category, whereas mixed modules randomly ordered practice radiographs after all categories had been taught. Medical students in Years 1-3 were randomised to either module and were tested on 20 new CXRs immediately after completion and at 2 weeks. The primary outcome was immediate diagnostic accuracy. Secondary outcomes included diagnostic accuracy at 2 weeks, time per module and reported module difficulty. RESULTS: A total of 58 medical students participated (32 in the blocked and 26 in the mixed module). Level of training and previous CXR experience were similar across the groups. Totals of 1160 and 1120 answers were evaluated for immediate and 2 week post-test scores, respectively. There were no significant differences in mean diagnostic accuracy between the blocked (mean score: 11.7/20) and mixed (mean score: 11.0/20) practice groups on immediate testing (t = 0.83, d.f. = 56, p = 0.41) or at 2 weeks (mean score: 11.2/20 versus 10.9/20; t = 0.518, d.f. = 54, p = 0.61). Post-test scores showed no correlation with training level (R = 0.23, p = 0.09) or completion time (R = -0.09, p = 0.5). Reported module difficulty was similar between the mixed (3.22/5) and blocked (3.19/5) groups. On multivariable linear regression controlling for completion time, training level and CXR experience, between-group differences remained non-significant. CONCLUSIONS: Performance after mixed practice was similar to that after blocked practice. Results may reflect similarities between modules in teaching, which emphasised contrast learning, greater effect of initial teaching rather than practice, or absence of tutor-led instruction. Alternatively, results may reflect the higher cognitive load in mixed practice imposed by contrasting multiple diagnoses.

Fluoroscopic evaluation of oropharyngeal dysphagia: anatomic, technical, and common etiologic factors.

OBJECTIVE: The purposes of this article are to review the anatomy of the upper gastrointestinal tract; review techniques and contrast agents used in the fluoroscopic examination of the oropharynx and hypopharynx; provide a pictorial review of some important causes of oropharyngeal dysphagia; and link these causes to key findings in the clinical history to assist in establishing a clinical diagnosis. CONCLUSION: Many important causes and presentations of oropharyngeal dysphagia are sometimes overlooked during conventional upper gastrointestinal studies. Videofluoroscopic evaluation for assessment of both structural abnormalities and motility disorders of the oropharynx by use of various compositions of barium contrast medium is the standard of practice. Using best-practices radiographic techniques and having knowledge of swallowing mechanisms and various diseases are important for assessment of dysphagia. Dynamic fluoroscopic imaging remains an essential tool for assessing functional disorders of swallowing. Detailed videofluoroscopic assessment can guide treatment decisions with the goal of decreasing the secondary complications of dysphagia.

Imaging Features of Gastrointestinal Neoplasms Complicating Inflammatory Bowel Diseases.

Inflammatory bowel diseases (IBD) are chronic inflammatory diseases affecting the gastrointestinal (GI) tract. Patients with IBD, besides other non-neoplastic complications, are also at increased risk of GI malignancies such as colorectal cancer, small bowel adenocarcinoma and lymphoma. The principal purpose of imaging in patients with IBD to assess complications and to stage a clinically known cancer. In addition, the goal of imaging has expanded to include the diagnosis of GI malignancies in clinical situations where colonoscopy cannot be performed or is incomplete. In addition, imaging allows the detection of cancers in patients where the development of either disease-related or treatment-related neoplasia is clinically suspected. The purpose of this review is to present the different imaging techniques used to detect GI malignancies in IBD patients and describe the radiological appearances of GI malignancies in IBD patients.

Guide to surgical procedures on hollow viscera: part 1--Esophageal, gastric, and restrictive bariatric procedures.

OBJECTIVE: The objective of this article is to explore with a surgical perspective the key radiologic features after common esophageal, gastric, and bariatric procedures. CONCLUSION: An understanding of procedures on the hollow viscera is essential for radiologists at any level. The ability to quickly recognize postoperative anatomy is critical to accurately and efficiently interpret routine imaging studies and to diagnose postoperative complications.

Guide to surgical procedures on hollow viscera: part 2--Colorectal, ostomy, and malabsorptive bariatric procedures.

OBJECTIVE: The objective of this article is to explore with a surgical perspective the key radiologic features of common bariatric, colorectal, and ostomy procedures. The images and diagrams show relevant postoperative anatomy. CONCLUSION: An understanding of procedures on the hollow viscera is essential for a radiologist at any level. The ability to quickly recognize postoperative anatomy is critical to accurately and efficiently interpret routine imaging studies and to diagnose postoperative complications.

A rare presentation of hypovolemic shock secondary to Whipple's disease.

Whipple's disease is a rare, multisystem infection caused by the Gram-positive Tropheryma whippelii organism. In addition to neurological and rheumatological manifestations, this disease can result in significant gastrointestinal symptoms such as malabsorption, diarrhea, and weight loss. Given the diagnostic challenge and rare occurrence, a high index of suspicion is critical to prevent morbidity and mortality from this otherwise highly infectious disease transmitted via the fecal-oral route. We present a very rare but near-fatal case of hypovolemic shock secondary to protein-losing enteropathy and gastrointestinal bleeding from small bowel T. whippelii infection. Furthermore, the epidemiology, clinical presentation, diagnosis, and management of Whipple's disease is reviewed.

Comprehensive Imaging and Surgical Review of Urinary Diversions: What the Radiologist Needs to Know.

Urinary diversions are surgical procedures that reconstruct the lower urinary tract following cystectomy. The 2 common surgical approaches are based on the continence status of the urinary tract. Incontinent diversions have continuous urine drainage through a cutaneous stoma, whereas continent diversions offer the patient the ability to self-void either via stoma catheterization or with the patient's own urethra. Given the large number of diversion procedures available, postsurgical anatomy may be complex. Multiple imaging modalities can be used to assess the postprocedural anatomy, potential complications, and for on-going oncologic monitoring. The purpose of this review is to describe the common surgical techniques and associated complications.

Clinical Practice Guidelines for the Assessment of Uninvestigated Esophageal Dysphagia.

BACKGROUND AND AIMS: Our aim is to review the literature and provide guidelines for the assessment of uninvestigated dysphagia. METHODS: A systematic literature search identified studies on dysphagia. The quality of evidence and strength of recommendations were rated according to the Grading of Recommendation Assessment, Development, and Evaluation (GRADE) approach. Statements were discussed and revised via small group meetings, teleconferences, and a web-based platform until consensus was reached by the full group. RESULTS: The consensus includes 13 statements focused on the role of strategies for the assessment of esophageal dysphagia. In patients presenting with dysphagia, oropharyngeal dysphagia should be identified promptly because of the risk of aspiration. For patients with esophageal dysphagia, history can be used to help differentiate structural from motility disorders and to elicit alarm features. An empiric trial of proton pump inhibitor therapy should be limited to four weeks in patients with esophageal dysphagia who have reflux symptoms and no additional alarm features. For patients with persistent dysphagia, endoscopy, including esophageal biopsy, was recommended over barium esophagram for the assessment of structural and mucosal esophageal disease. Barium esophagram may be useful when the availability of endoscopy is limited. Esophageal manometry was recommended for diagnosis of esophageal motility disorders, and high-resolution was recommended over conventional manometry. CONCLUSIONS: Once oropharyngeal dysphagia is ruled out, patients with symptoms of esophageal dysphagia should be assessed by history and physical examination, followed by endoscopy to identify structural and inflammatory lesions. If these are ruled out, then manometry is recommended for the diagnosis of esophageal dysmotility.

Pictorial essay: the value of rectal water in the assessment of rectosigmoid pathology.

The rectosigmoid region is a common location for the development of both malignant and benign diseases of the large bowel in adults. In many cases, rectal water provides an ideal contrast agent in the evaluation of rectosigmoid pathology. It allows optimal visualization of the mural layers and pericolic fat, as well as superior detection of flat or small sessile mural-based intralumenal filling defects. The authors of this article have devised practical clinical indications for the administration of rectal water that may help guide the radiologist in deciding when to implement this technique. Furthermore, this pictorial essay will describe the technique used by the authors, highlight the utility of this technique, and explore its practical applications and limitations in clinical practice.

Improved Diagnosis and Navigation for CT Colonography.

The goal of this research project is to develop a fast, accurate, and patient-friendly computer-aided diagnosis (CAD) component of CT colonography, that improves the robustness and accuracy of current colon wall segmentation and achieves earlier colorectal cancer diagnoses through an improved polyp detection method. Many advanced image processing techniques are applied to clearly outline the colon wall in the CT data set of human abdomen, and subtract the colon portion from the entire data set. After the subtraction, the detailed information and the surface curvature information on the colon wall is analyzed. The active contour model is assisted by presegmentation steps including mathematical morphology filtering, edge detection and other image processing techniques.