Scintigraphy of Gastrointestinal Motility: Best Practices in Assessment of Gastric and Bowel Transit in Adults.

Various radiologic examinations and other diagnostic tools exist for evaluating gastrointestinal diseases. When symptoms of gastrointestinal disease persist and no underlying anatomic or structural abnormality is identified, the diagnosis of functional gastrointestinal disorder is frequently applied. Given its physiologic and quantitative nature, scintigraphy often plays a central role in the diagnosis and treatment of patients with suspected functional gastrointestinal disorder. Most frequently, after functional gallbladder disease is excluded, gastric emptying scintigraphy (GES) is considered the next step in evaluating patients with suspected gastric motility disorder who present with upper gastrointestinal symptoms such as dyspepsia or bloating. GES is the standard modality for detecting delayed gastric emptying (gastroparesis) and the less commonly encountered clinical entity, gastric dumping syndrome. Additionally, GES can be used to assess abnormalities of intragastric distribution, suggesting specific disorders such as impaired fundal accommodation or antral dysfunction, as well as to evaluate gastric emptying of liquid. More recently, scintigraphic examinations for evaluating small bowel and large bowel transit have been developed and validated for routine diagnostic use. These can be performed individually or as part of a comprehensive whole-gut transit evaluation. Such scintigraphic examinations are of particular importance because clinical assessment of suspected functional gastrointestinal disorder frequently fails to accurately localize the site of disease, and those patients may have motility disorders involving multiple portions of the gastrointestinal tract. The authors comprehensively review the current practice of gastrointestinal transit scintigraphy, with diseases and best imaging practices illustrated by means of case review. ©RSNA, 2024 See the invited commentary by Maurer and Parkman in this issue.

Imaging evaluation of lymphoma in pregnancy with review of clinical assessment and treatment options.

Lymphoma-related malignancies can be categorized as Hodgkin's lymphoma (HL) or non-Hodgkin's lymphoma (NHL) based on histologic characteristics. Although quite rare during pregnancy, HL and NHL are the fourth and fifth most common malignancies during the pregnancy period, respectively. Given the rarity of lymphoma among pregnant patients, radiologists are usually unfamiliar with the modifications required for staging and treatment of this population, even those who work at centers with busy obstetrical services. Therefore, this manuscript serves to not only review the abdominopelvic imaging features of lymphoma in pregnancy, but it also discusses topics including birthing parent and fetal lymphoma-related prognosis, both antenatal and postpartum, current concepts in the management of pregnancy-related lymphoma, as well as the current considerations regarding birthing parent onco-fertility.

Sonographic assessment of infectious diseases of the gastrointestinal tract: from scanning to diagnosis.

BACKGROUND: Sonography of the gastrointestinal (GI) tract is a practical, safe, inexpensive, and reproducible diagnostic tool for the evaluation, diagnosis, and follow-up of infectious bowel disease. The modality is rapidly gaining prominence among clinicians on a global scale. In the United States, however, ultrasound of the bowel remains underutilized primarily due to insufficient experience among radiologists and sonographers in performing sonographic bowel assessment. This lack of experience and knowledge results in misinterpretations, missed diagnoses, and underutilization of this modality in patients with acute abdomen, with the majority of GI pathology on sonography discovered incidentally. OBJECTIVES: This article aims to demonstrate the characteristic sonographic findings associated with GI infectious processes as well as provide dedicated ultrasound protocols for evaluation of the GI tract. CONCLUSION: This article serves a twofold purpose, raising awareness of the utility of this imaging modality within the radiology community and also providing practical teaching points for sonographic evaluation of infectious disorders of the GI tract.

The radiologist's guide to duplex ultrasound assessment of chronic mesenteric ischemia.

OBJECTIVE: This article reviews the relevant anatomy and physiology of the mesenteric vasculature, familiarizes the radiologist with the accepted diagnostic criteria for mesenteric artery stenosis and its role in the diagnosis of chronic mesenteric ischemia, describes Doppler imaging techniques, and provides protocols for the assessment and surveillance of the mesenteric vasculature before and after revascularization. It also discusses expected changes following revascularization and reviews common post-procedural complications. RESULTS: Duplex sonography plays an important role in the diagnosis and management of chronic mesenteric ischemia (CMI). Establishing a successful diagnosis is dependent upon knowledge of mesenteric arterial anatomy and physiology as well as sufficient expertise in image optimization and scanning techniques. Although there has been a trend toward utilization of other noninvasive [computed tomographic angiography (CTA), magnetic resonance angiography (MRA), and invasive (digital subtraction angiography (DSA)] imaging modalities for assessment of the mesenteric vasculature, a new era of "imaging wisely" raises legitimate concerns about the effects of ionizing radiation as well as potential effects of CT and MR contrast agents. These concerns are obviated by the use of ultrasound, and recently developed techniques, such as contrast-enhanced ultrasound and vascular applications focused on the evaluation of slow flow, have revealed the vast potential of vascular ultrasound in the evaluation of chronic mesenteric ischemia. CONCLUSION: Duplex sonography is a cost-effective and powerful tool that can be utilized for the accurate assessment of mesenteric vascular pathology, specifically mesenteric arterial stenosis, and for the evaluation of mesenteric arterial system post revascularization.

Productivity, part 1: getting things done, using e-mail, scanners, reference managers, note-taking applications, and text expanders.

In an era of declining reimbursements and tightening of the job market, today's radiologists are forced to "make do with less." With the rollout of the Patient Protection and Affordable Care Act, commonly called "Obamacare," radiologists will be expected not only to interpret studies but to also take on many additional roles, adding a new layer of complexity to already demanding daily duties. These changes make it more important than ever to develop a personal workflow management system incorporating some of the most potent productivity tools. In this article, the authors discuss current productivity techniques and related software with the most potential to help radiologists keep up with the ever increasing demands on their time at the work place and help us lead more balanced lives.

Fetal lung maturity assessment with MRI fetal lung-to-liver signal-intensity ratio.

OBJECTIVE: The purpose of this study was to retrospectively determine whether the ratio of fetal lung-to-liver signal intensities at single-shot fast spin-echo MRI is associated with fetal gestational age. MATERIALS AND METHODS: All fetal MRI examinations over a 4-year period were reviewed. All MRI examinations were performed with a 1.5-T magnet for indications other than lung maturity. Only examinations performed with a single-shot fast spin-echo sequence of the fetal chest and abdomen were included in the study. Images from a total of 82 fetal MRI examinations were evaluated. Gestational age ranged from 20 weeks to 39 weeks 3 days. Two board-certified subspecialty-trained radiologists with 11 and 17 years of experience blinded to estimated gestational age (EGA) reviewed the images independently. The regions of interest (ROIs) of the fetal lung and liver were drawn in the same plane and on the same image in each case. Fetal EGA was determined either by first-trimester ultrasound when available or by last menstrual period. Linear regression analysis was used to analyze the relation between the lung-to-liver signal-intensity ratio (LLSIR) in the ROIs and fetal EGA for both readers. The association between the LLSIRs estimated by the two readers was assessed by Bland-Altman plot. RESULTS: Summary statistics for LLSIR showed a median value of 2.29 for reader 1 and 2.21 for reader 2. The mean value for reader 1 was 2.4 and for reader 2 was 2.5. The Pearson correlation coefficients between the LLSIR and EGA variables were 0.44 for reader 1 and 0.45 for reader 2. Linear regression analysis showed a statistically significant association between LLSIR and EGA for both readers (p < 0.0004). This ratio increased in a linear manner as EGA progressed. CONCLUSION: Fetal LLSIR at single-shot fast spin-echo MRI is associated with fetal gestational age.

Gestatational trophoblastic disease: multimodality imaging assessment with special emphasis on spectrum of abnormalities and value of imaging in staging and management of disease.

Gestational trophoblastic disease is a spectrum of disorders of varying malignant potential arising from trophoblastic cells and encompassing hydatidiform moles and persistent trophoblastic neoplasia. Ultrasound is the initial imaging investigation of choice when gestational trophoblastic disease is suspected. Complete hydatiform mole, the most common form of molar pregnancy, usually has a characteristic "cluster of grapes" appearance, especially on second-trimester ultrasounds. Persistent trophobastic neoplasia usually appears as a focal, hypervascular myometrial mass on pelvic ultrasound. Pelvic magnetic resonance imaging is often used as a problem-solving tool in equivocal or complicated cases of gestational trophoblastic disease to assess the degree of invasion into the myometrium and surrounding tissues. Chest x-ray, brain magnetic resonance imaging, and body computed tomography scans are primarily used for the evaluation of metastatic disease, which usually occurs in the context of choriocarcinomas. Choriocarcinoma metastases are usually hypervascular and have a tendency to bleed, features that are reflected in their imaging appearance.