Technical and Interpretive Pitfalls in Adrenal Imaging.

The adrenal gland may exhibit a wide variety of pathologic conditions. A number of imaging techniques can be used to characterize these, although it is not always possible to attain a definitive diagnosis radiologically. Incorrect diagnoses may be made if radiologists are not attentive to technical parameters and interpretive factors associated with adrenal gland imaging. Hence, an appreciation of the intricacies of adrenal imaging strategies and characterization is required; this can be aided by understanding the pitfalls of adrenal imaging. Technical pitfalls at CT may relate to the imaging parameters, including region of interest characteristics, tube voltage selection, and the timing of contrast material-enhanced imaging. With MRI, imaging acquisition technique and evaluation of the reference tissues used in chemical shift MRI are important considerations that can directly influence image interpretation. Interpretive errors may occur when evaluating adrenal washout at CT without considering other radiologic features, including the size of adrenal nodules, the presence of fat or calcification, the attenuation of nodules, and atypical imaging features. The characterization of an incidental adrenal lesion as benign or malignant does not end the role of the radiologist; consideration as to whether an adrenal lesion is associated with endocrine dysfunction is required. While imaging may not be optimal for establishing endocrine activity, there are imaging features from which radiologists may infer function. In cases of known endocrine activity, imaging can guide clinical management, including further investigations such as venous sampling. ©RSNA, 2020.

CT of Normal Developmental and Variant Anatomy of the Pediatric Skull: Distinguishing Trauma from Normality.

The use of computed tomography (CT) in clinical practice has been increasing rapidly, with the number of CT examinations performed in adults and children rising by 10% per year in England. Because the radiology community strives to reduce the radiation dose associated with pediatric examinations, external factors, including guidelines for pediatric head injury, are raising expectations for use of cranial CT in the pediatric population. Thus, radiologists are increasingly likely to encounter pediatric head CT examinations in daily practice. The variable appearance of cranial sutures at different ages can be confusing for inexperienced readers of radiologic images. The evolution of multidetector CT with thin-section acquisition increases the clarity of some of these sutures, which may be misinterpreted as fractures. Familiarity with the normal anatomy of the pediatric skull, how it changes with age, and normal variants can assist in translating the increased resolution of multidetector CT into more accurate detection of fractures and confident determination of normality, thereby reducing prolonged hospitalization of children with normal developmental structures that have been misinterpreted as fractures. More important, the potential morbidity and mortality related to false-negative interpretation of fractures as normal sutures may be avoided. The authors describe the normal anatomy of all standard pediatric sutures, common variants, and sutural mimics, thereby providing an accurate and safe framework for CT evaluation of skull trauma in pediatric patients.

Hepatic lipid profiling in chronic hepatitis C: an in vitro and in vivo proton magnetic resonance spectroscopy study.

BACKGROUND & AIMS: Hepatic steatosis is an important factor in pathogenesis, progression and response to treatment in hepatitis C. We aimed to investigate differences in hepatic lipid composition in liver biopsies from patients with chronic hepatitis C using proton magnetic resonance spectroscopy ((1)H MRS) and to translate these findings to the in vivo clinical setting. METHODS: Two cohorts of patients with histologically defined chronic hepatitis C were studied. High-resolution MR spectra were obtained from 47 liver biopsy samples. These data were used to derive biologically relevant prior knowledge for the assignment and interpretation of lower-resolution in vivo hepatic MRS data acquired at 1.5T from a second cohort of 59 patients. MRS data were obtained both in vitro and in vivo from a subset of 11 patients. RESULTS: Multivariate factor analysis demonstrated characteristic MR spectral differences by fibrosis stage and genotype. Total lipid increased with fibrosis stage (r=0.43, p=0.003) and was higher in genotype 3 compared to genotype 1 (p=0.03), while lipid polyunsaturation decreased with increasing fibrosis stage (r=-0.55, p<0.0005) and, independently, with increasing steatosis. Non-invasive assessment using in vivo hepatic (1)H MRS corroborated in vitro findings, but the signal-to-noise ratio was insufficient for reliable assessment of lipid polyunsaturation in vivo. CONCLUSIONS: Hepatic lipid composition was analysed using MRS in patients with chronic hepatitis C in vitro and in vivo, demonstrating significant differences in indices by disease severity. High-resolution data informed the analysis and interpretation of in vivo spectra, but further improvements in spectral quality in vivo are required.

Evaluating changes in gastrointestinal endoscopy training over 5 years: closing the audit loop.

BACKGROUND: An audit in 2002 showed that colonoscopy training in a large London training region was poorly structured, with the quality of supervision below recommendations and high reported complication rates. In 2004, the UK National Endoscopy Training Programme introduced centrally funded, accredited courses and new assessment tools to standardize training and raise the quality of colonoscopy by improving the skills of practicing endoscopists. AIM: To evaluate the changes in the standard of colonoscopy training over the last 5 years. METHODS: Questionnaires used in the earlier study were updated and e-mailed to all gastroenterology trainees in the region and those who participated in the earlier study. Trainees completed and returned the forms electronically. RESULTS: Twenty-six out of 37 gastroenterology trainees responded (70.3%). Significantly more trainees said that they had been formally taught the principles of colonoscopy (91 vs. 65%; P = 0.02), polypectomy (81 vs. 52%; P = 0.02) and extubation (88 vs. 56%; P = 0.01) than in 2002, and reported that complication rates were lower. Trainers displayed more appropriate teaching strategies and course attendance had significantly increased (84 vs. 48%, P = 0.003). Eighty-seven percent of the trainees thought that their training had been adequate or better than adequate, compared with 25% in 2002. CONCLUSION: In the 2007 survey, trainees reported a significant improvement both in colonoscopy training at base hospitals and in access to specialist courses compared with those in the 2002 survey. The centrally funded training programme has made a significantly positive impact in this large training region that is likely to be reflected elsewhere in England. The loss of such investment may have a detrimental effect on future colonoscopy training and the quality of service provision.