Michael F. McNeeley

Imaging of the Diaphragm: Anatomy and Function

The diaphragm is the primary muscle of ventilation. Dysfunction of the diaphragm is an underappreciated cause of respiratory difficulties and may be due to a wide variety of entities, including surgery, trauma, tumor, and infection. Diaphragmatic disease usually manifests as elevation at chest radiography. Functional imaging with fluoroscopy (or ultrasonography or magnetic resonance imaging) is a simple and effective method of diagnosing diaphragmatic dysfunction, which can be classified as paralysis, weakness, or eventration. Diaphragmatic paralysis is indicated by absence of orthograde excursion on quiet and deep breathing, with paradoxical motion on sniffing. Diaphragmatic weakness is indicated by reduced or delayed orthograde excursion on deep breathing, with or without paradoxical motion on sniffing. Eventration is congenital thinning of a segment of diaphragmatic muscle and manifests as focal weakness. Treatment of diaphragmatic paralysis depends on the cause of the dysfunction and the severity of the symptoms. Treatment options include plication and phrenic nerve stimulation. Supplemental material available at http://radiographics.rsna.org/lookup/suppl/doi:10.1148/rg.322115127/-/DC1.

Hepatocellular carcinoma in the noncirrhotic liver.

OBJECTIVE Hepatocellular carcinomas (HCCs) that arise in noncirrhotic livers have several histologic and biochemical features that distinguish them from HCCs occurring in the setting of cirrhosis. Because the presentation, management, and prognosis of these entities are distinct, the accurate preoperative characterization of these lesions is of great clinical significance. We review the pathogenesis, imaging appearance, and clinical implications of noncirrhotic HCCs as they pertain to the clinical radiologist. CONCLUSION HCCs that develop in noncirrhotic patients have distinct etiologic, cytogenetic, histopathologic, and clinical features. Despite a larger tumor burden at the time of HCC diagnosis, noncirrhotic patients with HCC have better overall survival and disease-free survival than cirrhotic patients with HCC. Knowledge of the precise clinical and imaging features of this entity and of other diagnostic considerations for the noncirrhotic liver is essential for improved patient care.

The Emotional Wellness of Radiology Trainees

RATIONALE AND OBJECTIVES Burnout is a complex phenomenon characterized by emotional exhaustion, social detachment, and feelings of low personal achievement. In this study, we aim to establish the prevalence of burnout among radiology trainees and to explore the factors influencing its development. MATERIALS AND METHODS Survey data were collected from 266 trainee members of the Association of University Radiologists to assess financial status, attitudes toward money and compensation, and burnout symptomology. Descriptive and inferential statistics were used to analyze these data. RESULTS Most radiology residents reported high levels of personal achievement but routine symptoms of emotional exhaustion and depersonalization. Although increasing levels of household debt were correlated with symptoms of depersonalization and lower reported quality of life, we found that the subjective financial experience was a more reliable indicator of emotional well-being. Specifically, higher subjective self-assessments of financial strain were the best predictors of symptoms of depersonalization (P < .0001), emotional exhaustion (P < .0001), and lower self-reported quality of life (P < .0001). Additionally, residents with recent moonlighting activity reported higher levels of personal achievement (P < .05), lower levels of emotional exhaustion (P < .05), and greater quality of life (P < .05) when compared to non-moonlighters. CONCLUSIONS The unique nature of radiology training could mean that traditional assumptions regarding the development of trainee burnout do not necessarily apply. Finances may be an underappreciated influence on resident burnout, and subjective feelings of financial scarcity could outweigh the impact of objective indebtedness. Further study is needed to ensure that the emotional well-being of radiology trainees is optimally supported.

Imaging of Granulomatous Fibrosing Mediastinitis

OBJECTIVE The purpose of this article is to review and illustrate the pathogenesis, natural history, imaging features, and treatment of granulomatous fibrosing mediastinitis. CONCLUSION Granulomatous fibrosing mediastinitis is an infiltrative disorder characterized by encasement of the mediastinal viscera; in most cases in the United States, it represents an idiosyncratic immune response to histoplasma. Familiarity with the various imaging features of fibrosing mediastinitis is important for prompt and accurate diagnosis as well as for planning and guiding surgical and less-invasive treatments.

Burnout in Radiology

Burnout is a psychological syndrome that arises in the setting of prolonged work-related stress. Although its specific manifestations are highly variable, the core features of burnout include emotional exhaustion, callousness or apathy towards patients or peers, and feelings of personal inadequacy. Burnout can have profound consequences for the affected physician, his or her patients, and the health care system at large. Increased rates of substance abuse, depression, and suicide have been linked to physician burnout, as have medical errors and lapses in patient safety. Disruptive workplace behaviors, such as presenteeism (which is reduced productivity due to physical or emotional dysfunction), absenteeism (which is nonparticipation in work), high employment turnover, and early retirement also have been linked to physician burnout and depression. In this article, we review causes, preventive measures and possible solutions for physician burnout.

The Nature and Scope of Moonlighting by Radiology Trainees

RATIONALE AND OBJECTIVES The practice of moonlighting by trainees is a longstanding controversy; however, the resident point of view remains distinctly underrepresented in the radiology literature. We report the resident perspective on the moonlighting practices of radiology trainees. METHODS Survey data were collected from resident members of the Association of University Radiologists representing 84 training programs in the United States to assess their routine and extracurricular clinical responsibilities. Descriptive statistics were used to analyze these data. RESULTS Moonlighting is practiced by radiology trainees at nearly three-fourths of the programs represented in this survey. Interpreting diagnostic imaging (85.5%) and monitoring contrast administrations (72.6%) are the most common duties performed. Twenty-one percent of moonlighting trainees perform procedures (excluding diagnostic fluoroscopy) in their extracurricular positions; of these, most (61.5%) are without attending supervision. Most trainees that moonlight spend 1 to 10 hours weekly doing so while averaging a 59-hour workweek at their primary jobs. CONCLUSIONS The clinical duties of moonlighting trainees may be more diverse than has been previously recognized. Although major discrepancies between overnight radiology trainee interpretations and attending final interpretations have been shown to be infrequent, the consequences of trainees performing procedures and monitoring adverse contrast reactions without attending supervision are unknown. The financial and professional benefits of moonlighting must be weighed against the potential for harm. Our data suggest that most moonlighting radiology trainees operate within the Accreditation Council for Graduate Medical Education-mandated 80-hour weekly work limit; the mandatory 8-hour break between shifts and 24-hour continuous duty limit may pose logistical challenges.

Percutaneous drainage of intra-abdominal abscess in children with perforated appendicitis

BackgroundBecause the surgical management of perforated appendicitis remains controversial, percutaneous catheter drainage (PCD) has gained favor for managing periappendiceal abscess in hemodynamically stable children.ObjectiveTo determine the safety and effectiveness of PCD in children with perforated appendicitis and to identify any variables of prognostic value.Materials & methodsWe retrospectively evaluated clinical data and imaging features for 33 children undergoing PCD for periappendiceal abscess from October 2006 to February 2010. Those with preprocedural CT studies were assigned to one of three risk categories based on imaging features.ResultsAppendectomy was successfully postponed for all patients. Our technical success rate was 87.9%, with three recurrences (two requiring repeat drainage, one managed conservatively) and one possible complication (enterocutaneous fistula formation). Children with large and diffuse abscesses had a 50% rate of technical failure, which was significantly increased when compared to children with large but localized abscesses (P < 0.028). Extraluminal appendicolith, extraluminal gas, leukocytosis, ileus/obstruction and procedural variables were not reliable predictors of outcome.ConclusionPCD can be effective for managing perforated appendicitis in children. Children with large and ill-defined abscess might be at increased risk for complication or recurrence.

Vertebral Artery Transection in Nonpenetrating Trauma: A Series of 4 Patients

Blunt cerebrovascular injury is a common and potentially devastating consequence of nonpenetrating trauma to the head and neck. The degree of injury ranges from minimal intimal disruption to complete transection with free extravasation. Although blunt carotid transection has been well characterized in clinical reports and radiologic studies, the computed tomographic angiography (CTA) features of blunt vertebral artery transection have not been well described. We report a series of 4 patients presenting to our level I trauma center with blunt vertebral artery transection, with an emphasis on their CTA imaging findings at presentation and their respective clinical courses. A brief review of the pertinent literature is provided.

Follicular thyroid carcinoma presenting as acute cord compression due to thoracic vertebral metastasis

Thyroid carcinoma is uncommon but accounts for roughly 95% of all cancers of the endocrine system (1). The “well-differentiated” thyroid tumors include the papillary, follicular, and Hurthle cell subtypes. Although the management of these tumor types generally is similar, important diagnostic and clinical differences do exist (2). We present a case of follicular thyroid carcinoma with spinal metastasis, illustrate its imaging features on CT and MR imaging with histologic correlations, and discuss how vertebral osseous metastasis may influence clinical management of patients with differentiated thyroid cancer.

The sonographic stenosis index: computer simulation of a novel method for detecting and quantifying arterial narrowing.

Purpose We introduce a new technique for quantifying arterial stenoses, stenosis index (SI), using frequency analysis of the spectral Doppler waveform. Methods Spectral Doppler waveforms obtained distal to arterial stenoses were enveloped, and the envelope was transformed into the frequency domain via Fourier transform. Stenosis index represents the ratio of the power in high-frequency harmonics to the power in the fundamental frequency. Stenosis index was compared with resistive index (RI), pulsatility index (PI), and acceleration time using 1000 computer simulations of waveforms from arteries distal to transplanted renal artery stenoses using Kendall tau correlation coefficients and receiver operating characteristic curve analyses. Results The mean r2’s using Kendall tau correlation for SI, RI, and PI were 0.58, 0.31, and 0.45, respectively. The 95% confidence intervals for increase in r2’s for SI versus RI and PI to the degree of stenosis (none, mild, and severe) in the 1000 computer simulations were 0.22 to 0.34 and 0.07 to 0.19. The difference between the areas under the curves for SI versus RI and PI for normal artery versus mild stenosis was 0.26 to 0.44 and 0.078 to 0.24. Stenosis index and acceleration time were not significantly different. Conclusions In computational models, SI outperformed RI and PI in correlation and receiver operating characteristic curve analysis. Further testing of SI is warranted.