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Radiopharmaceuticals are widely accepted to be a very safe class of drugs, with very few adverse reactions and unexpected biodistributions. However, problems can arise because of technical issues in manufacture or reconstitution, patient preparation, or drug administration. This review presents highlights of issues that have arisen in the newer classes of radiopharmaceuticals in the last 20 years and expands the scope of the previous report to include PET and therapeutic radiopharmaceuticals. Variations in the "quality" of the eluate of a (99)Mo/(99m)Tc generator remain a major issue. Several of the newer (99m)Tc tracers require a heating step in preparation that can also lead to unacceptably low radiochemical purity. Radiolytic breakdown can be a problem with all classes of radiopharmaceuticals. Many of the newer radiopharmaceuticals localize by receptor- or transporter-mediated processes and thus can be affected by other drugs, making patient preparation more important than ever. Therapeutic radiopharmaceuticals may require coadministration of radioprotectant regimens, such as the use of lysine-arginine infusions with radiopeptide therapy. Extravasation can have serious consequences with therapeutic radiopharmaceuticals. Adverse reactions to newer radiopharmaceuticals remain rare, though may increase because of coadministration of agents such as contrast media. However, there is known to be underreporting of minor adverse reactions. Knowledge of the pitfalls that can occur with radiopharmaceuticals is important in the interpretation of nuclear medicine images and optimal patient care., (Copyright © 2015 Elsevier Inc. All rights reserved.)

PET/CT imaging has become an important part of the evaluation of patients with many types of cancer. This imaging modality can also be used to image areas of active inflammation, such as those occurring in patients with active inflammatory bowel disease (IBD) (Crohn's disease and ulcerative colitis). The standard methods of determining a patient's disease activity are either indirect, such as blood and stool tests, or invasive, such as colonoscopy. FDG-PET imaging is a noninvasive, direct method of evaluating bowel inflammation and represents a significant advancement in the care of these patients. The PET/CT technique is very similar to that used for oncology imaging. Minor changes can be instituted to improve the accuracy, as well as to reduce the radiation exposure to the patient. This paper reviews the literature on the use of FDG-PET imaging in IBD in both the adult and pediatric populations. Future improvements in the technique should focus on decreasing the radiation dose to the patient and on decreasing the cost of the examination. The FDG-PET/CT technique is an excellent method for the noninvasive quantification of bowel inflammation in patients with IBD., (© 2013 Elsevier Inc. All rights reserved.)

The cardiac stress imposed by hemodialysis may differ from that induced by pharmacologic agents used for myocardial perfusion imaging-based stress testing. With repetitive intradialytic [(13)N]ammonia positron emission tomography, we showed that standard hemodialysis had an acute adverse effect on cardiac perfusion and left ventricular function that was not detected by standard diagnostic adenosine stress testing., (Copyright © 2012 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.)

Both positron emission tomography (PET) and computed tomography (CT) contribute significantly to the effective dose from PET/CT imaging. For PET imaging, the effective dose is related to the administered activity and age of patient. For CT, there are many factors that determine effective dose. Effective dose is dependent on tube current (mA), tube potential (kVp), rotation speed, pitch, slice thickness, patient mass, and the exact volume of the patient that is being imaged. The CT scan may be acquired at exposure parameters similar to those used for diagnostic CT, but more commonly, the tube current is reduced and a localization CT scan of somewhat less than optimal diagnostic quality is obtained. A very low dose CT scan for attenuation correction may also be considered.