Brian F. Mullan

FDG-PET imaging and the diagnosis of non-small cell lung cancer in a region of high histoplasmosis prevalence

STUDY OBJECTIVE Determine the sensitivity and specificity of [F-18]-fluorine-2-deoxy-D-glucose positron emission tomography (FDG-PET) in differentiating non-small cell lung cancer (NSCLC) from benign solitary pulmonary nodules (SPNs) in a region with a high endemic rate of histoplamosis. DESIGN Prospective, clinical study. SETTING University, tertiary referral hospital in the upper Mississippi River valley. PATIENTS Ninety patients with SPNs. INTERVENTIONS Independent interpretation of FDG-PET imaging, computed tomography and pathologic evaluation of the SPNs. MEASUREMENTS AND RESULTS To detect malignant SPNs, FDG-PET imaging had a sensitivity of 93%, a specificity of 40%, a positive predictive value (PPV) of 88% and a negative predictive value (NPV) of 55%. CONCLUSIONS In a region with a high prevalence of pulmonary fungal infection, FDG-PET is sensitive but has a low specificity and NPV for identifying NSCLC. In our study cohort, FDG-PET does not appear to reduce the need for SPN biopsies.

Choosing a specialty in medicine: Female medical students and radiology

OBJECTIVE The purpose of this study was to determine whether there are identifiable factors that dissuade female medical students from entering the field of radiology. MATERIALS AND METHODS An anonymous survey was completed by medical students at the end of their third- or fourth-year radiology clinical clerkships at five institutions. In addition to demographic data and residency choice, respondents ranked 10 factors in order of importance to their choice of career. For respondents who did not consider radiology a possible career, a second set of eight factors was ranked for importance in dissuading them. RESULTS Two hundred eighty-eight respondents completed the survey, 152 (53%) men and 136 (47%) women. Both men and women reported direct patient contact and intellectual stimulation as the most important factors in deciding on a specialty. For those who chose radiology, intellectual stimulation and use of emerging technology were significantly (p < 0.05) more important than other factors. The factor that most strongly (96%) dissuaded men and women from a career in radiology was lack of direct patient contact. There was no significant difference between men and women in ranking factors that dissuaded them from applying to radiology residencies; however, nearly one third of the female respondents cited competitiveness of the residency process as important. CONCLUSION Patient contact remains an important factor for medical students choosing a career. To attract high-caliber students, medical schools should expose students to areas of radiology involving patient interaction. Academically qualified women should be identified early during their careers and encouraged to apply for radiology residencies.

Evaluation of Speakers at a National Radiology Continuing Medical Education Course

Abstract: Purpose: Evaluations of a national radiology continuing medical education (CME) course in thoracic imaging were analyzed to determine what constitutes effective and ineffective lecturing. Methods and Materials: Evaluations of sessions and individual speakers participating in a fiveday course jointly sponsored by the Society of Thoracic Radiology (STR) and the Radiological Society of North America (RSNA) were tallied by the RSNA Department of Data Management and three members of the STR Training Committee. Comments were collated and analyzed to determine the number of positive and negative comments and common themes related to ineffective lecturing. Results: Twenty-two sessions were evaluated by 234 (75.7%) of 309 professional registrants. Eighty-one speakers were evaluated by an average of 153 registrants (range, 2 – 313). Mean ratings for 10 items evaluating sessions ranged from 1.28 ? 2.05 (1=most positive, 4=least positive; SD .451 - .902). The average speaker rating was 5.7 (1=very poor, 7=outstanding; SD 0.94; range 4.3 – 6.4). Total number of comments analyzed was 862, with 505 (58.6%) considered positive and 404 (46.9%) considered negative (the total number exceeds 862 as a “comment” could consist of both positive and negative statements). Poor content was mentioned most frequently, making up 107 (26.5%) of 404 negative comments, and applied to 51 (63%) of 81 speakers. Other negative comments, in order of decreasing frequency, were related to delivery, image slides, command of the English language, text slides, and handouts. Conclusions: Individual evaluations of speakers at a national CME course provided information regarding the quality of lectures that was not provided by evaluations of grouped presentations. Systematic review of speaker evaluations provided specific information related to the types and frequency of features related to ineffective lecturing. This information can be used to design CME course evaluations, design future CME course outcomes studies, provide training to presenters, and monitor presenter performance.

A Curriculum in Cardiothoracic Radiology for Medical Students, with Goals and Objectives

The Liaison Committee on Medical Education is the accrediting body for medical education programs leading to the MD degree in the United States and Canada. According to the Committee’s accreditation standards (1), “The curriculum must provide grounding in the body of knowledge represented in the disciplines that support the fundamental clinical subjects, for example, diagnostic imaging and clinical pathology.” In a survey of 119 directors of medical student education in radiology, 46 (39%) responded to questions regarding the teaching of radiology to medical students at their institution (2). A core radiology clerkship was required at 13 (29%) of 46 schools responding and was an elective at 33 (72%) (2). The number of schools with a required radiology clerkship has not changed since 1994 (3). The clerkship is given in the 3rd year at 12 (26%) of 46 schools, in the 4th year at 20 (44%), and in either the 3rd or 4th year at 14 (30%) (2). Twenty-six (57%) of 46 programs have computers in the department that students use during the course, usually shared with residents. Reported simultaneously with these survey results were results from a second survey of directors of medical student education, in which 69 (50%) of 139 responded (2). Six (9%) of 69 responding programs directed the medical school’s gross anatomy course, and 14 (20%) taught some portion of the course. A telephone survey (4) showed that a formal dedicated radiology clerkship was a graduation requirement in only five of the 16 top-ranked medical schools in a U.S. News & World Report ranking (Cornell, Duke, Harvard, University of California at San Francisco, and University of California at Los Angeles) (5). In contrast, a survey of 322 nonradiologist physicians showed that 87% believed formal radiology instruction should be mandatory (6). Radiology can be taught to medical students through an integrated curriculum, an independent curriculum, or a combination of the two. In an integrated curriculum, radiology faculty provide radiology instruction to medical students rotating through a nonradiology course or a course that is jointly sponsored by radiology and nonradiology departments. For example, radiologists teach projectional and cross-sectional imaging to medical students enrolled in a gross anatomy course. Radiologists may give a series of imaging lectures related to topics covered in a required medicine clerkship. Collaboration can occur when radiology faculty participate in required introductory courses that expose students early in medical school to physical examination techniques, history taking, and writing patient notes. These courses have various titles, such as “Introduction to Clinical Medicine” or “Patient, Doctor, and Society.” Radiology faculty can provide correlative imaging instruction in most required courses. The Alliance of Medical Student Educators in Radiology is a group associated with the Association of University Radiologists whose purpose is to promote radiology as an essential component of the medical student curricuAcad Radiol 2001; 8:1247–1251

Evaluation of in vivo total and regional air content and distribution in primate lungs with high-resolution CT

RATIONALE AND OBJECTIVES The authors sought to determine whether gray-scale quantitative information from high-resolution computed tomography (CT) could reliably yield estimates of lung air content and help determine changes in air content with lung inflation and deflation. MATERIALS AND METHODS High-resolution CT images (n = 40) of lungs of two anesthetized monkeys were obtained after inflation with known air volumes. Percentage air content was calculated for each voxel, and lung volumes and patterns of air distribution were determined. RESULTS When corrected for pressure and temperature, high-resolution CT-based volumes correlated closely with inflation volumes (r = .99; standard error = 3.4%). Patterns of regional change in air content demonstrated known patterns of ventilation. CONCLUSION Although the high-spatial-frequency algorithm used in high-resolution CT enhances edges of structures and improves visualization of anatomic detail, gray-scale values from the same high-resolution CT data set remain a reliable index of regional lung attenuation.

Mediastinal lymphatic drainage from pulmonary lobe based on CT observations of histoplasmosis: implications for minimal N2 disease of non-small-cell lung cancer

PurposeThe aim of this study was to assess mediastinal lymphatic drainage patterns from each pulmonary lobe using computed tomographic (CT) observations of calcified primary complex pulmonary histoplasmosis.Materials and methodsWe assessed 400 CT studies of patients with primary complex histoplasmosis consisting of a single lobe pulmonary lesion and mediastinal nodal disease. We assessed the distribution of mediastinal nodal involvement depending on pulmonary lobes for the total number of involved nodes, the number with single-station involvement (which suggests the initial site of involvement), and the number with skip involvement which suggests direct drainage to the mediastinum.ResultsThe most commonly involved mediastinal nodal stations from the right upper lobe, left upper lobe, and left lower lobe were the right lower paratracheal node (97%, 74/76), the subaortic node (72%, 49/68), and the left pulmonary ligament node (61%, 66/108), respectively. These nodes were the most common site of skip involvement in each lobe. In the right lower lobe and middle lobe, the subcarinal node was most commonly involved: 62% (65/105) and 81% (35/43), respectively. By contrast, skip involvement was uncommon in the drainage to this node.ConclusionOur data show a predictable pattern of lobar lymphatic drainage to the mediastinum. This may have implications on the minimal N2 disease of non-small-cell lung cancer.