Obesity is a chronic disease that is now a global epidemic. The numbers of obese people are exponentially rising in Europe, and it is projected that in Europe by 2010 there will be 150 million obese people. The obesity-related health crisis does not only affect adults, with one in four European children now overweight. Radiologists, both adult and paediatric, need to be aware of the magnitude of the problem, and obese patients cannot be denied radiologic evaluation due to their size. Missed diagnosis, appointment cancellation and embarrassing situations for patients when they are referred for a radiological examination for which they are not suitable are all issues that can be avoided if careful provision is made to accommodate the needs of the obese patient requiring radiologic evaluation. This paper will discuss the epidemiology of obesity and the role of radiology in the assessment of obesity and disorders of fat metabolism. The limitations obesity poses to current radiological equipment and how the radiologist can optimise imaging in the obese patient will be described. Dose reference levels and dose control are discussed. Examples of how obesity both hinders and helps the radiologist will be illustrated. Techniques and pre-procedural preparation to help the obese patient in the interventional suite are discussed.

OBJECTIVE The joint guidelines of the American College of Cardiology and American Heart Association support the use of contrast-enhanced MR angiography (CEMRA) to diagnose the location and degree of stenosis in patients with known or suspected peripheral arterial disease (PAD). The high prevalence of chronic renal impairment in diabetic patients with PAD and the need for high doses of gadolinium-based contrast agents place them at risk for nephrogenic systemic fibrosis. The purpose of our study was to evaluate the accuracy of the rapid technique of quiescent-interval single-shot (QISS) unenhanced MR angiography (MRA) compared with CEMRA for the diagnosis in diabetic patients referred with symptomatic chronic PAD. SUBJECTS AND METHODS This prospective two-center study evaluated 25 consecutive diabetic patients with documented or suspected symptomatic PAD. Both centers used identical imaging protocols. Images were independently analyzed by two radiologists. A subgroup analysis was performed of patients who were also assessed with digital subtraction angiography (DSA) as part of the standard-of-care protocol before revascularization. RESULTS For this study, 775 segments were analyzed. On a per-segment basis, the mean values of the diagnostic accuracy of unenhanced MRA compared with reference CEMRA for two reviewers, reviewers 1 and 2, were as follows: sensitivity, 87.4% and 92.1%; specificity, 96.8% and 96.0%; positive predictive value, 90.8% and 94.0%; and negative predictive value, 95.5% and 94.6%. Substantial agreement was found when overall DSA results were compared with QISS unenhanced MRA (κ = 0.68) and CEMRA (κ = 0.63) in the subgroup of patients who also underwent DSA. There was almost perfect agreement between the two readers for stenosis scores, with Cohen’s kappa values being greater than 0.80 for both MRA techniques. CONCLUSION The results of our study indicate that QISS unenhanced MRA is an accurate noncontrast alternative to CEMRA for showing clinically significant arterial disease in patients with diabetes with symptomatic PAD.

Purpose To evaluate two nonenhanced MRA methods: quiescent-interval single-shot (QISS) and Native SPACE (NATIVE= Non-contrast Angiography of the Arteries and Veins; SPACE = Sampling Perfection with Application Optimized Contrast by using different flip angle Evolution), using contrast-enhanced MR angiography (CEMRA) as a reference standard. Materials and Methods 20 patients (14 male, mean 69.3 years old) referred for lower extremity MRA were recruited in a HIPAA-compliant prospective study. QISS and Native SPACE of the lower extremities were performed at 1.5T with a hybrid dual-injection contrast-enhanced MRA as reference. Image quality and stenosis severity were assessed in segments by two blinded radiologists. Methods were compared with logistic regression for correlated data for diagnostic accuracy. Results Of 496 arterial segments, 24 were considered non-diagnostic on the Native SPACE images. There were no QISS or CEMRA imaging segments considered to be non-diagnostic. Image quality was significantly higher for QISS than for Native SPACE. QISS stenosis sensitivity (84.9%) was not significantly different from Native SPACE (87.3%). QISS had better specificity (95.6%) than Native SPACE (87.0%), p=0.0041. In comparison with QISS, Native SPACE proved less robust for imaging of the abdominal and pelvic segments. Conclusion Native SPACE and QISS were sensitive for hemodynamically significant stenosis in this pilot study. QISS NEMRA demonstrated superior specificity and image quality, and was more robust in the abdominal and pelvic regions.

A 40-year-old white man was admitted for excision of a subcutaneous lesion on his torso. He reported a 12-month history of shortness of breath and exertional chest pain, both of which were relieved by rest. The patient was otherwise asymptomatic, and physical examination was noncontributory. He was not taking any medications. Electrocardiographic monitoring during the procedure revealed third-degree heart block with junctional escape and right bundle-branch block at 38 bpm ( Figure 1). The patient was hemodynamically stable. An electrophysiology consultation was requested, and the patient was found to have an elevated serum angiotensin-converting enzyme level. Histological examination of the biopsy specimen showed noncaseating granulomata, which confirmed the diagnosis of sarcoidosis.The patient had had an ungated noncontrast chest computed tomographic examination performed approximately 1 month earlier that showed mediastinal and hilar lymphadenopathy ( Figure 2) along with multiple subcentimeter lung nodules (Figure 3). In retrospect, it demonstrated infiltration of the epicardial fat surrounding the right coronary artery within the atrioventricular groove (Figure 4).A cardiac magnetic resonance study was performed that showed hypokinesis of the basal portions of the left ventricle and interventricular septum (Movie 1), with associated myocardial delayed enhancement ( Figure 5). There was infiltration of the epicardial fat surrounding the right coronary artery ( Figure 6). Less severe infiltration was present along the course of the left anterior descending coronary artery. There Figure 1. Twelve-lead ECG taken 8 minutes after procedure while the patient was in recovery. This shows third-degree heart block with right bundle-branch block and a rate of 38 bpm.