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.

Grade V renal trauma management: results from the multi-institutional genito-urinary trauma study.

PURPOSE: To investigate management trends for American Association for the Surgery of Trauma (AAST) grade V renal trauma with focus on non-operative management. METHODS: We used prospectively collected data as part of the Multi-institutional Genito-Urinary Trauma Study (MiGUTS). We included patients with grade V renal trauma according to the AAST Injury Scoring Scale 2018 update. All cases submitted by participating centers with radiology images available were independently reviewed to confirm renal trauma grade. Management was classified as expectant, conservative (minimally invasive, endoscopic or percutaneous procedures), or operative (renal-related surgery). RESULTS: Eighty patients were included, 25 of whom had complete imaging and had independent confirmation of AAST grade V renal trauma. Median age was 35 years (Interquartile range (IQR) 25-50) and 23 (92%) had blunt trauma. Ten patients (40%) were managed operatively with nephrectomy. Conservative management was used in nine patients (36%) of which six received angioembolization and three had a stent or drainage tube placed. Expectant management was followed in six (24%) patients. Transfusion requirements were progressively higher with groups requiring more aggressive treatment, and injury characteristics differed significantly across management groups in terms of hematoma size and laceration size. Vascular contrast extravasation was more likely in operatively managed patients though a statistically significant association was not found. CONCLUSION: Successful use of nonoperative management for grade V injuries is used for a substantial subset of patients. Lower transfusion requirement and less severe injury radiologic phenotype appear to be important characteristics delineating this group.

MR Defecating Proctography with Emphasis on Posterior Compartment Disorders.

MR defecating proctography (MRDP) is a noninvasive examination that can be used for evaluating posterior compartment disorders. MRDP has several advantages over conventional fluoroscopic defecography. These benefits include high-contrast resolution evaluation of the deep pelvic organs, simultaneous multicompartmental assessment that is performed statically and dynamically during defecation, and lack of ionizing radiation. MRDP also provides a highly detailed anatomic evaluation of the pelvic floor supportive structures, including direct assessment of the pelvic floor musculature and indirect assessment of the endopelvic fascia. As the breadth of knowledge regarding anatomic and functional posterior compartment disorders expands, so too does the advancement of noninvasive and surgical treatment options for these conditions. High-quality MRDP examinations, with key anatomic and functional features reported, guide treatment planning. Reporting of MRDP examination findings with use of standardized terminology that emphasizes objective measurements rather than subjective grading aids consistent communication among radiologists, clinicians, and surgeons. Familiarity with commonly encountered posterior compartment pelvic floor pathologic entities that contribute to posterior compartment disorders and awareness of the essential information needed by surgeons are key to providing an optimal multidisciplinary discussion for planning pelvic floor dysfunction treatment. The authors provide an overview of the basic concepts of the MRDP acquisition technique, the anatomic abnormalities of posterior compartment pelvic floor pathologic entities associated with defecatory disorders, and recently developed interdisciplinary MRDP reporting templates and lexicons. In addition, the associated imaging findings that are key for surgical treatment guidance are highlighted. © RSNA, 2022 Online supplemental material is available for this article.

A Method for Reducing Variability Across Dual-Energy CT Manufacturers in Quantification of Low Iodine Content Levels.

BACKGROUND. Clinical use of the dual-energy CT (DECT) iodine quantification technique is hindered by between-platform (i.e., across different manufacturers) variability in iodine concentration (IC) values, particularly at low iodine levels. OBJECTIVE. The purpose of this study was to develop in an anthropomorphic phantom a method for reducing between-platform variability in quantification of low iodine content levels using DECT and to evaluate the method's performance in patients undergoing serial clinical DECT examinations on different platforms. METHODS. An anthropomorphic phantom in three body sizes, incorporating varied lesion types and scanning conditions, was imaged with three distinct DECT implementations from different manufacturers at varying radiation exposures. A cross-platform iodine quantification model for correcting between-platform variability at low iodine content was developed using the phantom data. The model was tested in a retrospective series of 30 patients (20 men, 10 women; median age, 62 years) who each underwent three serial contrast-enhanced DECT examinations of the abdomen and pelvis (90 scans total) for routine oncology surveillance using the same three DECT platforms as in the phantom. Estimated accuracy of phantom IC values was summarized using root-mean-square error (RMSE) relative to known IC. Between-platform variability in patients was summarized using root-mean-square deviation (RMSD). RMSE and RMSD were compared between platform-based IC (ICPB) and cross-platform IC (ICCP). ICPB was normalized to aorta and portal vein. RESULTS. In the phantom study, mean RMSE of ICPB across platforms and other experimental conditions was 0.65 ± 0.18 mg I/mL compared with 0.40 ± 0.08 mg I/mL for ICCP (38% decrease in mean RMSE; p < .05). Intrapatient between-platform variability across serial DECT examinations was higher for ICPB than ICCP (RMSD, 97% vs 88%; p < .001). Between-platform variability was not reduced by normalization of ICPB to aorta (RMSD, 97% vs 101%; p = .12) or portal vein (RMSD, 97% vs 97%; p = .81). CONCLUSION. The developed cross-platform method significantly decreased between-platform variability occurring at low iodine content with platform-based DECT iodine quantification. CLINICAL IMPACT. With further validation, the cross-platform method, which has been implemented as a web-based app, may expand clinical use of DECT iodine quantification, yielding meaningful IC values that reflect tissue biologic viability or treatment response in patients who undergo serial examinations on different platforms.

Imaging review of penile pathologies encountered in the emergency department.

While penile pathology is uncommon, prompt diagnosis and treatment of emergent and urgent penile pathology are necessary to prevent complications. This paper will review the imaging findings of the most common critical penile pathologies, including traumatic, vascular, infectious, foreign body-related, and urethral pathology, in addition to penile prosthesis complications. Each entity will be discussed in the context of presentation and treatment and complications of each pathology will be discussed.

Pitfalls in the interpretation of pediatric head CTs: what the emergency radiologist needs to know.

Pediatric radiology studies can be some of the most anxiety-inducing imaging examinations encountered in practice. This can be in part due to the wide range of normal anatomic appearances inherent to the pediatric population that create potential interpretive pitfalls for radiologists. The pediatric head is no exception; for instance, the inherent greater water content within the neonatal brain compared to older patients could easily be mistaken for cerebral edema, and anatomic variant calvarial sutures can be mistaken for skull fractures. This article reviews potential pitfalls emergency radiologists may encounter in practice when interpreting pediatric head CTs, including trauma, extra-axial fluid collections, intra-axial hemorrhage, and ventriculoperitoneal shunt complications.

Rethinking Clinical Trial Radiology Workflows and Student Training: Integrated Virtual Student Shadowing Experience, Education, and Evaluation.

There is consistent demand for clinical exposure from students interested in radiology; however, the COVID-19 pandemic resulted in fewer available options and limited student access to radiology departments. Additionally, there is increased demand for radiologists to manage more complex quantification in reports on patients enrolled in clinical trials. We present an online educational curriculum that addresses both of these gaps by virtually immersing students (radiology preprocessors, or RPs) into radiologists' workflows where they identify and measure target lesions in advance of radiologists, streamlining report quantification. RPs switched to remote work at the beginning of the COVID-19 pandemic in our National Institutes of Health (NIH). We accommodated them by transitioning our curriculum on cross-sectional anatomy and advanced PACS tools to a publicly available online curriculum. We describe collaborations between multiple academic research centers and industry through contributions of academic content to this curriculum. Further, we describe how we objectively assess educational effectiveness with cross-sectional anatomical quizzes and decreasing RP miss rates as they gain experience. Our RP curriculum generated significant interest evidenced by a dozen academic and research institutes providing online presentations including radiology modality basics and quantification in clinical trials. We report a decrease in RP miss rate percentage, including one virtual RP over a period of 1 year. Results reflect training effectiveness through decreased discrepancies with radiologist reports and improved tumor identification over time. We present our RP curriculum and multicenter experience as a pilot experience in a clinical trial research setting. Students are able to obtain useful clinical radiology experience in a virtual learning environment by immersing themselves into a clinical radiologist's workflow. At the same time, they help radiologists improve patient care with more valuable quantitative reports, previously shown to improve radiologist efficiency. Students identify and measure lesions in clinical trials before radiologists, and then review their reports for self-evaluation based on included measurements from the radiologists. We consider our virtual approach as a supplement to student education while providing a model for how artificial intelligence will improve patient care with more consistent quantification while improving radiologist efficiency.

CT Angiography of Left Atrial Appendage Occluder Device.

Online supplemental material is available for this article.

The American Association for the Surgery of Trauma Renal Grading System-Should Segmental Kidney Infarction be Classified as a Grade IV Injury?

PURPOSE: In 2018 the American Association for the Surgery of Trauma revised renal injury grading. One change was inclusion of segmental kidney infarction under grade IV injuries. We aimed to assess how segmental kidney infarction will change the scope of grade IV injuries and compare bleeding control interventions in those with and without isolated segmental kidney infarction. METHODS: We used high grade renal trauma data from 7 level 1 trauma centers from 2013 to 2018 as part of the Multi-institutional Genito-Urinary Trauma Study. Initial computerized tomography scans were reviewed to regrade the injuries. Injuries were categorized as isolated segmental kidney infarction if segmental parenchymal infarction was the only reason for inclusion under grade IV injury. All other grade IV injuries (including combined injury patterns) were categorized as without isolated segmental kidney infarction. Bleeding interventions were compared between those with and without isolated segmental kidney infarction. RESULTS: From 550 patients with high grade renal trauma and available computerized tomography, 250 (45%) were grade IV according to the 2018 American Association for the Surgery of Trauma grading system. Of these, 121 (48%) had isolated segmental kidney infarction. The majority of patients with isolated segmental kidney infarction (88%) would have been assigned a lower grade using the original 1989 grading system. Rate of bleeding control interventions was lower in isolated segmental kidney infarction compared to other grade IV injuries (7% vs 21%, p=0.002). Downgrading all patients with isolated segmental kidney infarction to grade III did not change the grading system's associations with bleeding interventions. CONCLUSIONS: Approximately half of the 2018 American Association for the Surgery of Trauma grade IV injuries have isolated segmental kidney infarction. Including isolated segmental kidney infarction in grade IV injuries increases the heterogeneity of these injuries without increasing the grading system's ability to predict bleeding interventions. In future iterations of the American Association for the Surgery of Trauma renal trauma grading isolated segmental kidney infarction could be reclassified as grade III injury.

Multimodality Imaging Review of Multiple Endocrine Neoplasia.

OBJECTIVE. The purpose of this article is to review the clinical manifestations, endocrine tumors types, and multimodality diagnostic tools available to physicians involved in the management of patients with multiple endocrine neoplasia (MEN) syndrome, in addition to discussing relevant imaging findings and appropriate imaging follow-up. CONCLUSION. Thorough knowledge of the spectrum of tumors associated with MEN gene mutations aids in the screening, diagnostic workup, and posttreatment monitoring of patients with MEN-related gene mutations.

Collaborative Writing Projects: Set Yourself up for Success.

ABSTRACT: This article will review critical components for the successful completion of a multi-institution, multiauthor collaborative paper. Best practices for the creation and publication of a collaborative paper will be addressed.

Imaging features of fungal pneumonia in haematopoietic stem cell transplant patients.

Patients who have received haematopoietic stem cell transplantation (HSCT) have a high rate of pulmonary complications, and in this immunosuppressed population, fungal pneumonia is of great concern. Fungal pneumonia can have a similar appearance to non-infectious pulmonary processes in HSCT patients, and radiologists should be familiar with the subtle features that may help to differentiate these disease entities. The focus of this article is on the diagnosis of fungal pneumonia in HSCT patients with an emphasis on radiologists' roles in establishing the diagnosis of fungal pneumonia and the guidance of clinical management.

An Algorithmic Approach to Complex Fetal Abdominal Wall Defects.

OBJECTIVE. The purpose of this article is to describe the imaging findings associated with complex fetal abdominal wall defects and provide an algorithmic method for arriving at a final diagnosis. CONCLUSION. Fetal ventral abdominal wall defects are a complex group of conditions with a broad spectrum of associated multisystem anomalies and manifestations. Correct characterization and classification of these defects require not only familiarity with imaging findings but also a systematic approach to avoid diagnostic confusion.

Alone: AJR Podcast Series on Wellness, Episode 2.

In this episode of the AJR Podcast Series on Wellness, Sherry Wang, MBBS, discusses being alone. The episode addresses how being alone can be conducive to wellness. Being alone is not the same as loneliness.

Dopamine Dressing: AJR Podcast Series on Wellness, Episode 4.

In this episode of the AJR Podcast Series on Wellness, Sherry Wang, MBBS, discusses dopamine dressing. What is it? How do you do it? How can it boost your mood for wellness?

Feeling Unwell: AJR Podcast Series on Wellness, Episode 1.

In this episode of the AJR Podcast Series on Wellness, Sherry Wang, MBBS, discusses feeling unwell. The episode addresses the state of physician burnout, depression, moral injury, and personal experiences.

Together: AJR Podcast Series on Wellness, Episode 3.

In this episode of the AJR Podcast Series on Wellness, Sherry Wang, MBBS, discusses how loneliness and social connectedness impact wellbeing and how we can connect with others to build meaningful relationships. These issues are important in view of the continued growth of teleradiology.

Clinical and Payer-Based Analysis of Value of Dual-Energy Computed Tomography for Workup of Incidental Abdominal Findings.

OBJECTIVE: To perform a clinical and payer-based analysis of the value of dual-energy computed tomography (DECT) for workup of incidental abdominal findings. METHODS: This was a single-center, retrospectively designed, Health Insurance Portability and Accountability Act-compliant study approved by our institutional review board. Sixty-nine examinations in 69 patients (45 men, 24 women; mean age, 57.7 years) who underwent single-phase postcontrast abdominal DECT studies between January 1, 2011, and December 31, 2017, were included. Two radiologists, blinded to study objective and design, reviewed all cases and identified incidental abdominal findings needing further imaging. All incidental findings were reviewed by 2 other investigators, who determined whether an imaging-based diagnosis could be made using DECT virtual noncontrast images and iodine maps. Additional studies and associated payer-reimbursement amounts avoided by use of DECT were estimated. All imaging costs were estimated based on the US Centers for Medicare & Medicaid Services reimbursement amounts. RESULTS: Thirty-four incidental findings (renal mass, n = 20; adrenal nodule, n = 8; pancreatic cystic lesions, n = 3; others, n = 3) were identified in 19 (27.5%) of 69 patients. Dual-energy computed tomography characterized 27 incidental findings in 15 patients and accounted for cost savings of 15 additional imaging examinations (abdominal magnetic resonance imaging, n = 11; abdominal computed tomography, n = 4). Based on Centers for Medicare & Medicaid Services reimbursement amounts, we estimated that, by abolishing the need for additional imaging use, DECT saved US $84.95 per patient. CONCLUSIONS: Dual-energy computed tomography can provide an imaging-based diagnosis of incidental abdominal findings, otherwise incompletely characterized on routine abdominal computed tomography, in approximately 21% of patients. In select patients, the monetary savings from abolishing additional imaging may reduce payer costs associated with use of DECT.

Quantitative Assessment of Liver Stiffness Using Ultrasound Shear Wave Elastography in Patients With Chronic Graft-Versus-Host Disease After Allogeneic Hematopoietic Stem Cell Transplantation: A Pilot Study.

OBJECTIVES: The purpose of this study was to compare hepatic stiffness on ultrasound (US) shear wave elastography (SWE) in patients with chronic graft-versus-host disease (GVHD) after allogeneic hematopoietic stem cell transplantation versus patients with no underlying liver disease. METHODS: We performed a retrospective analysis of 4901 patients who underwent abdominal US examinations with adjunctive liver SWE between August 2014 and December 2016. Each patient was scanned supine with gentle breath holding on LOGIQ E9 (GE Healthcare, Waukesha, WI) or Epiq (Philips Healthcare, Andover, MA) US machines (3-6 MHz). Three to 10 measurements were made intercostally in the right hepatic lobe, following manufacturers' guidelines before release of the 2015 Society of Radiologists in Ultrasound consensus or the 2015 Society of Radiologists in Ultrasound consensus. The median and standard deviation of the shear wave velocity (SWV) were obtained. A 2-sample t test with the Welch approximation was used for statistical analysis. RESULTS: Six patients had documented hepatic chronic GVHD or a high clinical suspicion of liver chronic GVHD. All had normal pretransplant liver function test results and no pretransplant or posttransplant hepatic infection. The control group, obtained from the same database, contained 10 patients with normal liver function test results, no abdominal pain, and no history of liver disease or conditions that may have caused liver stiffness changes. The SWVs in patients with chronic GVHD were double those in the control group (1.96 ± 0.28 versus 0.98 ± 0.27 m/s; P < .0001). CONCLUSIONS: Patients with chronic GVHD had substantially higher hepatic parenchymal SWVs than patients without liver disease, indicating increased tissue stiffness. To our knowledge, this phenomenon has not been previously reported in chronic GVHD and suggests potential utility of SWE for diagnosis and monitoring of disease progression and the treatment response in this cohort of patients.