Universal Fasting Glucose Screening Before Gastric Emptying Scintigraphy and the High Prevalence of Undiagnosed Diabetes and Prediabetes

The aim of this study was to assess the rates of undiagnosed diabetes mellitus (DM) and pre-DM in patients undergoing gastric emptying scintigraphy (GES). Diabetes is an epidemic in the United States, and the disease is associated with altered gut motility. As a result, we suspected that a significant number of patients referred for GES may have undiagnosed DM or pre-DM. Given that established procedure standards for GES require all patients to prepare with an 8-h fast, an opportunity is provided to measure the fasting blood glucose (FBG) in all individuals before they undergo the examination. Methods: The charts of patients undergoing GES were reviewed for a history of DM and correlated with FBG and GES results. FBG values, obtained by point-of-care testing, were categorized as normal, pre-DM, or DM. Results: Patients with known DM made up 23% of those referred for GES, and most (55%) had a normal FBG. In those without a history of DM, there were a significant number with undiagnosed pre-DM (12%) and DM (33%). Conclusion: Our study provides the first measure of the likely prevalence of undiagnosed DM and pre-DM and characterizes the different gastric emptying patterns among patients with normal FBG, likely undiagnosed pre-DM, likely undiagnosed DM, and known DM.

Improving DXA Quality by Avoiding Common Technical and Diagnostic Pitfalls: Part 1

Dual-energy x-ray absorptiometry (DXA) is an accurate means to assess bone mineral density, determine the risk of a fragility fracture, and monitor response to therapy. Despite its seemingly straightforward nature-the review of 2-to-3 nondiagnostic images and a few automatically generated numbers-the proper performance and interpretation of DXA can often be complex. It is complex because it is highly dependent on many factors, such as image acquisition, processing, analysis, and subsequent examination interpretation. Each step is subject to potential errors, artifacts, and diagnostic pitfalls; hence, meticulous attention must be paid to the technique by both the technologist and the interpreting physician to provide high-quality results and, in turn, maximize the examination's clinical utility. This article is part 1 of a 2-part series. Part 1 will begin with a review of bone physiology and osteoporosis etiology, followed by a discussion of the principles underlying DXA and the technical procedure. Part 2 will focus on DXA interpretation and discuss scanning pitfalls and clues to recognizing issues and improving scan quality.

18F-Fluciclovine Avid Axillary Lymph Nodes After COVID-19 Vaccination on PET/CT for Suspected Recurrence of Prostate Cancer

Abnormally increased ¹⁸F-FDG avidity of axillary lymph nodes has become a frequent diagnostic dilemma on PET/CT in the current climate of global vaccinations directed against severe acute respiratory syndrome coronavirus 2. This avidity is due to the inflammatory response evoked by vaccines and the nonspecific nature of ¹⁸F-FDG uptake, which is increased in both malignant and inflammatory processes. Similarly, ¹⁸F-fluciclovine, an amino acid analog indicated for the assessment of biochemical recurrence of prostate cancer, may also demonstrate nonspecific inflammatory uptake. We report a case of ¹⁸F-fluciclovine PET/CT obtained for concern about prostate cancer. In this case, isolated avid lymph nodes were seen in the left axilla. A screening questionnaire revealed that the patient had recently received the second dose of the Pfizer-BioNTech coronavirus disease 2019 vaccine in his left shoulder, and hence, the uptake was determined to be reactive.

Parotid Oncocytoma on 99mTc-Sestamibi Scintigraphy and SPECT/CT

ABSTRACT

Oncocytomas in the parotid gland are a rare benign neoplasm composed of mitochondrial-rich oncocytes. Here we present the case of an 85-year-old man with a history of biopsy-proven right parotid gland oncocytoma who underwent 99mTc-sestamibi scintigraphy and SPECT/CT in the context of primary hyperparathyroidism. Focal intense uptake of radiotracer is detected within the right parotid gland on sestamibi scintigraphy. SPECT/CT confirms the localization of sestamibi uptake to the hyperattenuating parotid gland oncocytoma.