Advances in Radiology http://www.hindawi.com The latest articles from Hindawi Publishing Corporation © 2015 , Hindawi Publishing Corporation . All rights reserved. Evaluating pH in the Extracellular Tumor Microenvironment Using CEST MRI and Other Imaging Methods Wed, 01 Jul 2015 07:54:38 +0000 http://www.hindawi.com/journals/ara/2015/206405/ Tumor acidosis is a consequence of altered metabolism, which can lead to chemoresistance and can be a target of alkalinizing therapies. Noninvasive measurements of the extracellular pH (pHe) of the tumor microenvironment can improve diagnoses and treatment decisions. A variety of noninvasive imaging methods have been developed for measuring tumor pHe. This review provides a detailed description of the advantages and limitations of each method, providing many examples from previous research reports. A substantial emphasis is placed on methods that use MR spectroscopy and MR imaging, including recently developed methods that use chemical exchange saturation transfer MRI that combines some advantages of MR spectroscopy and imaging. Together, this review provides a comprehensive overview of methods for measuring tumor pHe, which may facilitate additional creative approaches in this research field. Liu Qi Chen and Mark D. Pagel Copyright © 2015 Liu Qi Chen and Mark D. Pagel. All rights reserved. Imaging Findings and Evaluation of Metabolic Bone Disease Tue, 24 Mar 2015 09:29:19 +0000 http://www.hindawi.com/journals/ara/2015/812794/ Bone is a dynamic organ of the endoskeleton, playing an important role in structural integrity, mineral reservoirs, blood production, coagulation, and immunity. Metabolic bone disease encompasses a broad spectrum of inherited and acquired disorders that disrupt the normal homeostasis of bone formation and resorption. For patients affected by these processes, radiologic imaging plays a central role in diagnosis, monitoring treatment, and risk stratification. Radiologists should be familiar with the diseases, intimately aware of the imaging findings, and possessive of multimodality expertise to wisely guide the best practice of medicine. The purpose of this paper is to review the imaging features and characteristics of the most common types of metabolic bone disease with highlights of clinically relevant information so that readers can better generate appropriate differential diagnoses and recommendations. For this review, a thorough literature search for the most up-to-date information was performed on several key types of metabolic bone disease: osteoporosis, osteomalacia, rickets, scurvy, renal osteodystrophy, hyperparathyroidism, Paget’s disease, osteogenesis imperfecta, acromegaly, and osteopetrosis. Although they all affect the bone, these diseases have both shared characteristic features that can be discerned through imaging. Anish A. Patel, Rohit Ramanathan, Joshua Kuban, and Marc H. Willis Copyright © 2015 Anish A. Patel et al. All rights reserved. To Evaluate and Explain the Consequences of Abnormal Anal Sphincter Morphology Using the 3-Dimensional Endosonography Thu, 20 Nov 2014 09:40:46 +0000 http://www.hindawi.com/journals/ara/2014/131032/ The Objective of the Study. To evaluate and explain the consequences of different morphological abnormalities of anal sphincters including the sphincter damage and its extent using the 3-dimensional endosonography. Material and Methods. 56 patients suffering from fecal incontinence all were subjected to analysis of patient symptoms, scoring the severity of symptoms, digital examination, electromyography, and 3D endoanal ultrasonography. Results. 5 patients showed intact anal sphincters and puborectalis muscle. 4 patients found with thick IAS > 4 mm, 4 patients with thin IAS < 2 mm. 3 patients with thin EAS, 12 patients with IAS defects, 15 patients with EAS defects, 8 patients with combined IAS and EAS defects, 2 patients with puborectalis muscle defects and 3 patients with high levels transsphincteric perianal fistulas. Conclusion. No significant relationship was observed between sphincter damage except for combined internal and external sphincter injury and the severity score of FI symptoms. Puborectalis muscle injury and abnormal sphincter thickness are unlikely causes of severe FI. Ashraf Talaat Youssef Copyright © 2014 Ashraf Talaat Youssef. All rights reserved. Identifying Sources of Hepatic Lipogenic Acetyl-CoA Using Stable Isotope Tracers and NMR Mon, 11 Aug 2014 08:04:46 +0000 http://www.hindawi.com/journals/ara/2014/109252/ The role of hepatic de novo lipogenesis (DNL) in promoting fatty liver disease and hypertriglyceridemia during excessive nutrient intake is becoming firmly established. Certain nutrients such as fructose promote hepatic DNL activity and this has been at least partly attributed to their efficient conversion to the acetyl-CoA precursors of DNL. However, tracer studies indicate a paradoxically low level of fructose incorporation into lipids, which begs the question of what the actual lipogenic acetyl-CoA sources are under these and other conditions. Here, we describe novel approaches for measuring substrate contributions to lipogenic hepatic acetyl-CoA using 13C-tracers and 13C-NMR analysis of lipids and acetyl-CoA probes. We review and address aspects of hepatic intermediary fluxes and acetyl-CoA compartmentation that can confound the relationship between 13C-precursor substrate and lipogenic 13C-acetyl-CoA enrichments and demonstrate novel methodologies that can provide realistic estimates of 13C-enriched substrate contributions to DNL. The most striking realization is that the principal substrate contributors to lipogenic acetyl-CoA have yet to be identified, but they are probably not the so-called “lipogenic substrates” such as fructose. The proposed methods may improve our insight into the nutrient sources of DNL under various feeding and disease states. John G. Jones Copyright © 2014 John G. Jones. All rights reserved. An Assessment of Final-Year Medical Students and Interns Awareness of Radiation Exposure to Common Diagnostic Imaging Procedures Thu, 24 Jul 2014 11:46:29 +0000 http://www.hindawi.com/journals/ara/2014/426909/ Objectives. To evaluate the level of knowledge about the radiation exposure to diagnostic imaging procedures among the final-year medical students and interns and to suggest how education could be improved. Material and Methods. All 355 final-year medical students and interns from Tikur Anbessa Teaching Hospital in Addis Ababa were included in the study. Participants were asked to complete a questionnaire consisting of their actual knowledge on ionizing radiation and on their preferred method of learning. All questions were in multiple choice formats ranging from 4 to 7 choices. The obtained data were analyzed using statistical software. Results. A total of 343 completed questionnaires were received. Up to 78.9% of respondents underestimated or do not know the radiation dose from commonly requested radiological procedures. Surprisingly, 245 (71.4%) and 254 (79.3%) students incorrectly believed that ultrasound and MRI, respectively, emit ionizing radiation or they do not know if they emit radiation or not. Both interns and medical students did not have significant difference in their knowledge of ionizing radiation. A combination of tutorials or workshops (29.7%) and learning modules (19.8%) combined were their first and last preferred methods of teaching for future radiation awareness, respectively.  Conclusion. This study has clearly shown that awareness of ionizing radiation from diagnostic imaging is lacking among senior medical students and interns. The results highlight the need for improved education to minimize unnecessary exposure of patients. Seife Teferi Dellie, Daniel Admassie, and Yenework Ewnetu Copyright © 2014 Seife Teferi Dellie et al. All rights reserved. Variations in the Branching Pattern of the Aortic Arch Detected with Computerized Tomography Angiography Sun, 29 Jun 2014 11:21:32 +0000 http://www.hindawi.com/journals/ara/2014/969728/ Objectives. The aim was to determine the prevalence of aortic arch variations in 881 patients who underwent neck CT angiography for various reasons. Material and Methods. 881 patients were included in the study who had undergone neck CT angiography between 2010 and 2013. Results. Of 881 patients, 770 (87.4%) patients with classic branching pattern of the aortic arch (AA) were observed. Variations in branching pattern were seen in 111 (12.6%) patients. The most common variation was the origination of the left common carotid artery (LCCA) from the brachiocephalic trunk (BCT). This pattern was observed in 64 (7.2%) cases. In 25 (2.8%) cases, the left vertebral artery (LVA) originated directly from the AA between the origin of the LCCA and left subclavian artery (SCA). 17 (1.9%) cases had aberrant right subclavian artery. Three (0.3%) cases showed right aortic arch. Two cases had right aortic arch with aberrant left subclavian artery. Conclusions. Variations in the branching pattern of the AA are not rare. Head and neck surgeons and interventional radiologists should be aware of aortic arch variations. CTA is a reliable imaging method for demonstrating anatomical features and variations of the AA. Pasaoglu Lale, Ugur Toprak, Gökhan Yagız, Tunca Kaya, and Sadık Ahmet Uyanık Copyright © 2014 Pasaoglu Lale et al. All rights reserved.