Appearance of aseptic vascular grafts after endovascular aortic repair on [(18)F]fluorodeoxyglucose positron emission tomography/computed tomography.

BACKGROUND: Diagnosis of prosthetic vascular graft infection with [(18)F]fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) allows for early detection of functional changes associated with infection, based on increased glucose utilization by activated macrophages and granulocytes. Aseptic vascular grafts, like all foreign bodies, can stimulate an inflammatory response, which can present as increased activity on 18F-FDG PET/CT. Consequently, distinguishing aseptic inflammation from graft infection, though important, can be difficult. In the case of endovascular aneurysm repair (EVAR), a minimally invasive procedure involving the transfemoral insertion of an endoprosthetic stent graft, the normal postoperative appearance of these grafts on 18F-FDG PET/CT can vary over time, potentially confounding study interpretation. AIM: To investigate the visual, semiquantitative, and temporal characteristics of aseptic vascular grafts in patients status post EVAR. METHODS: In this observational retrospective cohort study, patients with history of EVAR who underwent 18F-FDG PET/CT for indications other than infection were identified retrospectively. All patients were asymptomatic for graft infection - no abdominal pain, fever of unknown origin, sepsis, or leukocytosis - at the time of imaging and for ≥ 2 mo after each PET/CT. Imaging studies such as CT for each patient were also reviewed, and any patients with suspected or confirmed vascular graft infection were excluded. One hundred two scans performed on 43 patients (34 males; 9 females; age = 77 ± 8 years at the time of the final PET/CT) were retrospectively reviewed. All 43 patients had an abdominal aortic (AA) vascular graft, 40 patients had a right iliac (RI) limb graft, and 41 patients had a left iliac (LI) limb graft. Twenty-two patients had 1 PET/CT and 21 patients had from 2 to 9 PET/CTs. Grafts were imaged between 2 mo to 168 mo (about 14 years) post placement. Eight grafts were imaged within 6 mo of placement, including three that were imaged within three months of placement. The mean interval between graft placement and PET/CT for all 102 scans was 51 ± 39 mo. PET/CT data was reconstructed with region-of-interest analysis of proximal, mid and distal portions of the grafts and background ascending aorta. Maximum standardized uptake value (SUVmax) was recorded for each region. SUVmax-to-background uptake ratios (URs) were calculated. Visual assessment was performed using a 2-pattern grading scale: Diffuse (homogeneous uptake less than liver uptake) and focal (one or more areas of focal uptake in any part of the graft). Statistical analysis was performed. RESULTS: In total, there were 306 AA grafts, 285 LI grafts, 282 RI grafts, and 306 ascending aorta background SUVmax measurements. For all 102 scans, mean SUVmax values for AA grafts were 2.8-3.0 along proximal, mid, and distal segments. Mean SUVmax values for LI grafts and RI grafts were 2.7-2.8. Mean SUVmax values for background were 2.5 ± 0.5. Mean URs were 1.1-1.2. Visual analysis of the scans reflected results of quantitative analysis. On visual inspection, 98% revealed diffuse, homogeneous 18F-FDG uptake less than liver. Graft URs and visual pattern categories were significantly associated for AA graft URs (F-ratio = 21.5, P < 0.001), LI graft URs (F-ratio = 20.4, P < 0.001), and RI graft URs (F-ratio = 30.4, P < 0.001). Thus, visual patterns of 18F-FDG uptake corresponded statistically significantly to semiquantitative URs. The age of grafts showing focal patterns was greater than grafts showing diffuse patterns, 87 ± 89 vs 50 ± 37 mo, respectively (P = 0.02). URs were significantly associated with graft age for AA grafts (r = 0.19, P = 0.001). URs were also significantly associated with graft age for LI grafts (r = 0.25, P < 0.0001), and RI grafts (r = 0.31, P < 0.001). Quartiles of similar numbers of graft (n = 25-27) grouped by graft age indicated that URs were significantly higher for 4th quartile vs 2nd quartile URs (F-ratio = 19.5, P < 0.001). When evaluating URs, graft SUVmax values within 10%-20% of the ascending aorta SUVmax is evident in aseptic grafts, except for grafts in the oldest quartiles. In this study, grafts in the oldest quartiles (> 7 years post EVAR) showed SUVmax up to 30% higher than the ascending aorta SUVmax. CONCLUSION: Characteristics of an aseptic vascular stent graft in the aorta and iliac vessels on 18F-FDG PET/CT include graft SUVmax values within 10%-20% of the ascending aorta background SUVmax. The SUVmax of older aseptic grafts can be as much as 30% above background. The visual uptake pattern of diffuse, homogeneous uptake less than liver was seen in 98% of aseptic vascular grafts, making this pattern particularly reassuring for clinicians.

Workforce Pathway Development: Evaluation of an Educational Seminar to Increase Student Interest in Nuclear Medicine.

RATIONALE AND OBJECTIVES: Attracting more students to nuclear medicine is imperative to improving diversity and meeting growing staffing needs. In this study, we implemented a short seminar about nuclear medicine and evaluated its impact on student perceptions of the field. MATERIALS AND METHODS: We developed and presented 30-minute "Introduction to Nuclear Medicine" seminars to undergraduate college students and preclinical medical students. After the seminars, participants completed a post-pre survey to determine perceived changes to their perspective of nuclear medicine. Responses were coded on a Likert 1-5 scale with pre- and post- seminar results compared using T-test of means and analysis of variance. RESULTS: Of the 83 students who attended the seminar, 79 (95.1%) students participated in the survey including 67 preclinical medical students and 12 undergraduate students. Of the 78 participants who provided demographic information, there were 38 (48.7%) women, 5 (6.4%) first-generation college students, and 39 (50.0%) people who identified as either multiracial or a race other than White/Caucasian. Among all participants (n = 79), there was a significant increase in perceived understanding of nuclear medicine (p < 0.001), confidence in ability to pursue nuclear medicine (p < 0.001), and interest in becoming a nuclear medicine professional (p < 0.001). Perceived increases in knowledge were highest among first-year medical students (p = 0.031), while interest (p = 0.40) and confidence (p = 0.85) in pursuing nuclear medicine did not vary by educational level. CONCLUSION: Perceptions of student interest in nuclear medicine can be improved using an easily implemented, short seminar at the undergraduate college and preclinical medical school level.

Outcomes After Laparoscopic Cholecystectomy in Hyperkinetic Biliary Dyskinesia.

BACKGROUND: Biliary dyskinesia (BD) is a poorly understood functional gallbladder disorder. Diagnosis is made with abdominal pain and an intact gallbladder without signs of anatomical obstruction on imaging or pathology. Our aim was to assess whether laparoscopic cholecystectomy (LC) resolves hyperkinetic BD symptoms. METHODS: Records of patients ≥18 years of age, who underwent LC by four surgeons at a tertiary care center between 2012 and 2020, were retrospectively reviewed. Patients were excluded if they had a documented gallbladder ejection fraction (GBEF) <80% or had biliary stones or sludge on pathology or imaging. Demographic information, HIDA results, preoperative testing, operative details, gallbladder pathology, and symptom status at follow-up were collected from electronic medical records. Improvement in BD symptoms was assessed using McNemar's test. Risk differences with standard errors were employed to estimate percent reduction in symptoms. RESULTS: Ninety-eight patients met inclusion criteria. Of those who presented for follow-up (n = 91), 92.3% (n = 84) reported partial or complete resolution of symptoms. Preoperative symptoms, including back pain (16.7%, 95% CI: [7.9%, 25.5%]; P < .0001), epigastric pain (31.1% [21.3%, 41.3%]; P < .0001), nausea (56.7% [45.0%, 65.8%]; P < .0001), RUQ pain (57.8% [46.1%, 66.9%]; P < .0001), and vomiting (27.8% [18.4%, 37.7%]; P < .0001) showed significant improvement after LC. Chronic cholecystitis and/or cholesterolosis were present on pathology in 79.8% of gallbladders. DISCUSSION: Our study currently represents the largest cohort of patients with hyperkinetic BD. Laparoscopic cholecystectomy appears to result in resolution of symptoms for this clinical entity.

Clinical characteristics associated with idiopathic rapid gastric emptying in patients referred for gastric emptying studies.

OBJECTIVES: Rapid gastric emptying (RGE) is diagnosed using nuclear medicine gastric emptying scintigraphy (GES). The clinical symptoms are non-specific and its pathophysiology in the absence of gastric surgery is poorly understood. We aimed to evaluate the clinical characteristics associated with idiopathic RGE. METHODS: GES studies were reviewed from a database of 1958 4-hour solid-phase GES performed over an 8-year period. RGE was defined as <30% of the test meal remaining in the stomach at 1 hour. Patients who had had any gastric operation were excluded. A chart review was conducted to extract patients' baseline data and clinical characteristics. RESULTS: Of the 1958 GES studies reviewed, 156 (8.0%) patients had RGE, and 534 (27.3%) had delayed gastric emptying (>10% retained food at 4 h), respectively. Idiopathic RGE constituted 22.6% (156/690) of all abnormal GES studies. The patients' average age at diagnosis was 54.0 years and 53.8% of patients with RGE were female. Most (69.2%) of these studies were ordered with an initial clinical suspicion of gastroparesis, compared with only 12.2% with a suspicion of RGE. Among this idiopathic RGE cohort, 71.2% presented with symptoms of nausea, 42.9% with vomiting, 32.1% with abdominal pain, 21.2% with bloating and 17.9% with early satiety. Only 7.7% presented with diarrhea, 0.6% with palpitations and 0.6% with hypoglycemia. CONCLUSIONS: Idiopathic RGE is an important differential diagnosis in patients with symptoms classically associated with gastroparesis. Few have postprandial diarrhea or palpitations as their presenting symptom. Further studies of idiopathic RGE syndrome are warranted.

Nuclear Medicine Education Via Instagram: A Viable Method for Informal Lifelong Learning.

Formal and informal lifelong learning allows nuclear medicine professionals to grow and change over time within this dynamic field. Over the past 2 decades, Internet-based websites have provided instantaneous access to informal learning opportunities, including nuclear medicine reference articles, videos and webinars, and case-based learning. More recently, medical educators have explored social media platforms such as Instagram, Facebook, and Twitter to provide nuclear medicine education. This article discusses the use of Instagram as a platform for lifelong learning in nuclear medicine. Several nuclear medicine Instagram sites are introduced and user characteristics and participation for a representative site are presented in an effort to learn more about this educational forum, which is increasingly being recognized among academic educators.

Intragastric Meal Distribution During Gastric Emptying Scintigraphy for Assessment of Fundic Accommodation: Correlation with Symptoms of Gastroparesis.

Impaired fundic accommodation (FA) limits fundic relaxation and the ability to act as a reservoir for food. Assessing intragastric meal distribution (IMD) during gastric emptying scintigraphy (GES) allows for a simple measure of FA. The 3 goals of this study were to evaluate trained readers' (nuclear medicine and radiology physicians) visual assessments of FA from solid-meal GES; develop software to quantify GES IMD; and correlate symptoms of gastroparesis with IMD and gastric emptying. Methods: After training to achieve a consensus interpretation of GES FA, 4 readers interpreted FA in 148 GES studies from normal volunteers and patients. Mixture distribution and κ-agreement analyses were used to assess reader consistency and agreement of scoring of FA. Semiautomated software was used to quantify IMD (ratio of gastric counts in the proximal stomach to those in the total stomach) at 0, 1, 2, 3, and 4 h after ingestion of a meal. Receiver-operating-characteristic analysis was performed to optimize the diagnosis of abnormal IMD at 0 min (IMD0) with impaired FA. IMD0, GES, water load testing, and symptoms were then compared in 177 patients with symptoms of gastroparesis. Results: Reader pairwise weighted κ-values for the visual assessment of FA averaged 0.43 (moderate agreement) for normal FA versus impaired FA. Readers achieved 84.0% consensus and 85.8% reproducibility in assessing impaired FA. IMD0 based on the division of the stomach into proximal and distal halves averaged 0.809 (SD, 0.083) for normal FA and 0.447 (SD, 0.132) (P < 0.01) for impaired FA. On the basis of receiver-operating-characteristic analysis, the optimal cutoff for IMD0 discrimination of normal FA from impaired FA was 0.568 (sensitivity, 86.7%; specificity, 91.7%). Of 177 patients with symptoms of gastroparesis, 129 (72.9%) had delayed gastric emptying; 25 (14.1%) had abnormal IMD0 Low IMD0 (impaired FA) was associated with increased early satiety (P = 0.02). Conclusion: FA can be assessed visually during routine GES with moderate agreement and high reader consistency. Visual and quantitative assessments of FA during GES can yield additional information on gastric motility to help explain patients' symptoms.

A successful model for longitudinal community-engaged health research: the 2040 Partners for Health Student Program.

Introduction: Community-based participatory research [CBPR] is an emerging approach to collaborative research aimed at creating locally effective and sustainable interventions. The 2040 Partners for Health student program was developed as a unique model of longitudinal CBPR. Analysis of this program and its components illuminates both the challenges and the opportunities inherent in community engagement. Methods: The program rests on a foundation of a community-based, non-profit organization and a supportive academic university centre. Inter-professional health students and community members of underserved populations work together on different health projects by employing an adapted CBPR methodology. Three successful examples of sustainable CBPR projects are briefly described. Results: The three projects are presented as primary outcomes resulting from this model. Benefits and challenges of the model as an approach to community-engaged research are discussed as well as secondary benefits of student participation. Conclusion: The 2040 Partners for Health student program represents a successful model of CBPR, illuminating common challenges and reiterating the profound value of community-engaged research.

Integrating The Integrated Skin Exam film into medical education.

AbstractBackgroundThe mortality rate for melanoma continues to rise and the greatest improvement in melanoma survival is attributable to early detection with skin cancer screening exams. However, physicians feel that limited training in the examination of skin and limited clinical time both serve as barriers to adequately assess high-risk lesions.ObjectiveTo test the use of The Integrated Skin Exam film as an instructional tool to teach the examination of skin in a live classroom setting, outside of the purview of the original formal study.MethodsIdentical cross-sectional surveys were administered pre- and post-film to a class of first-year medical students at the time of viewing The Integrated Skin Exam film. Results were compared to the initial assessment of this film as a teaching tool in a research setting.ResultsOf the maximum 182 possible surveys administered, we collected 148 pre-surveys and 142 post-surveys (81.3% and 78.0% 33 response rates, respectively). After viewing the film, students showed improvement in identification of high-risk demographic 34 groups (79.3% vs 58.9%, p<0.001) and high-risk anatomic sites in both women (91.9% vs 59.6%, p<0.001) and men (92% vs 35 62.1%, p<0.001). Students demonstrated increased confidence in the skin cancer examination (SCE) (52.2% vs 6.9%, p<0.001) and a greater proportion (74.4% vs 48.3%, p<0.001) of students believed less than 3 minutes was required to integrate a skin cancer exam (SCE) into the routine examination.ConclusionsThe Integrated Skin Exam film is a valuable training tool as proven by increased knowledge of, and improved attitudes about the 2 SCE after viewing the film. In addition, there was a striking similarity in outcomes when using this film in a live classroom 3 environment compared to the original study setting.

Compliance with acute stroke care quality measures in hospitals with and without primary stroke center certification: the North Carolina Stroke Care Collaborative.

BACKGROUND: Organized stroke care is associated with improved outcomes. Data are limited on differences in changes in the quality of acute stroke care at The Joint Commission-certified Primary Stroke Centers (PSCs) versus non-PSCs over time. METHODS AND RESULTS: We compared compliance with the Joint Commission's 10 acute stroke care performance measures and defect-free care in PSCs and non-PSCs participating in the Registry of the North Carolina Stroke Care Collaborative from January 2005 through February 2010. We included 29 654 cases presenting at 47 hospitals-10 PSCs, 8 preparing for certification, and 29 non-PSCs-representing 43% of North Carolina's non-Veterans Affairs, acute care hospitals. Using a non-PSC referent, odds ratios and 95% CIs were calculated using logistic regression and generalized estimating equations accounting for clustering of cases within hospitals. Time trends were presented graphically using simple linear regression. Performance measure compliance increased for all measures for all 3 groups in 2005-2010, with the exception of discharge on antithrombotics, which remained consistently high. PSCs and hospitals preparing for certification had better compliance with all but 2 performance measures compared with non-PSCs (each P<0.01). Defect-free care was delivered most consistently at hospitals preparing for certification (52.8%), followed by PSCs (45.0%) and non-PSCs (21.9%). Between 2005 and 2010, PSCs and hospitals preparing for certification had a higher average annual percent increase in the provision of defect-free care (P=0.01 and 0.04, respectively) compared with non-PSCs. CONCLUSIONS: PSC certification is associated with an overall improvement in the quality of stroke care in North Carolina; however, room for improvement remains.

miR in melanoma development: miRNAs and acquired hallmarks of cancer in melanoma.

Melanoma is a very aggressive skin cancer with increasing incidence worldwide. MicroRNAs are small, noncoding RNAs that regulate gene expression of targeted gene(s). The hallmark of cancer model outlined by Hanahan and Weinberg offers a meaningful framework to consider the roles of microRNAs in melanoma development and progression. In this systematic review of the literature, we associate what is known about deregulation of microRNAs and their targeted genes in melanoma development with the hallmarks and characteristics of cancer. The diagnostic and therapeutic potential of microRNAs for future melanoma management will also be discussed.

Monitoring and improving acute stroke care: The North Carolina Stroke Care Collaborative.

The North Carolina Stroke Care Collaborative is a stroke care quality-improvement (QI) program that provides performance data to hospitals continuously, allowing for rapid feedback and for development of QI initiatives. Between 2005 and 2012, 89,413 stroke cases were enrolled, and the proportion of patients receiving defect-free care improved from 52% to 79%. However, important areas for improvement remain.