Open-Source Ultrasound Trainer for Healthcare Professionals: A Pilot Randomized Control Trial.

INTRODUCTION: This technical report describes the development of a high-fidelity, open-source ultrasound trainer and showcases its abilities through a proof-of-concept, pilot randomized control trial. The open-source ultrasound trainer (OSUT) aims to enhance anatomical visualization during ultrasound education. The OSUT can attach to any ultrasound transducer, uses minimal hardware, and is able to be used during live patient ultrasound examinations. METHODS: After viewing a standardized training video lecture, 24 incoming first-year medical students with no prior ultrasound experience were randomized into a control group given an ultrasound system or an intervention group given the OSUT in addition to an ultrasound system. Both groups were tasked with localizing the thyroid, abdominal aorta, and right kidney on a patient. Performance outcomes were structure localization time, ultrasound image accuracy, and preactivity and postactivity participant confidence. RESULTS: The OSUT decreased right kidney localization time (Kruskal-Wallis, P < 0.001), increased sonographer right kidney accuracy ratings (Mann-Whitney U , U = 10.5, P < 0.05), and increased confidence in structure identification (Mann-Whitney U , U = 37, P = 0.045) and overall ultrasound ability (Wilcoxon signed-rank test, P = 0.007). There was no significant change in localization time, accuracy ratings, or participant confidence for locating the thyroid and abdominal aorta. CONCLUSIONS: A high-fidelity, open-source ultrasound trainer was developed to aid healthcare professionals in learning diagnostic ultrasound. The study demonstrated the potential beneficial effects of the OSUT in localizing the right kidney, showcasing its adaptability and accessibility for ultrasound education for certain anatomical structures.

Anatomical Considerations for Gallbladder Sonography: A Cross-Sectional Study of CT Imaging by BMI Group.

Objective The purpose of this study was to establish an association between the body mass index (BMI) group and anatomical gallbladder position to aid novices in gallbladder sonography. Methods This was a cross-sectional, Strengthening the Reporting of Observational Studies in Epidemiology (STROBE)-compliant study that examined the association between gender and the BMI group with quantitative gallbladder position measurements from computed tomography (CT) scans. Results A quantitative analysis determined that the gallbladder was positioned relatively higher and oriented more horizontally within the abdomen of individuals with obese BMI than those with normal BMI (p < 0.001), irrespective of gender. Additionally, the gallbladder was more obstructed by the rib cage in individuals with obese BMI than those with normal BMI (p = 0.007 for females and p < 0.001 for males). The gallbladder was significantly more horizontal in overweight males than females (p < 0.001) and more obstructed by the rib cage in obese males than females (p = 0.013). Conclusion This association provides ultrasound novices knowledge for a more targeted approach in localizing the gallbladder and evidence to recommend an intercostal approach for gallbladder sonography in obese patients.

Contrast-Enhanced Ultrasound Tumor Therapy With Abdominal Imaging Transducer.

A diagnostic ultrasound machine add-on module (AOM) was created to enable an off-the-shelf abdominal imaging transducer to perform contrast-enhanced therapeutic ultrasound. The AOM creates plane-wave ultrasound through an abdominal imaging transducer targeting intravascular microbubbles within tumors. This therapeutic antivascular ultrasound (AVUS) causes heating and cavitation effects that destroy tumor vasculature and starves it of nutrients. The AOM can switch between therapeutic and imaging modes for monitoring AVUS treatment. The therapeutic capability of the AOM was validated in murine hepatocellular carcinomas (HCC) grown in adult mice. Contrast-enhanced ultrasound imaging performed before and after the therapeutic treatment evaluated the AVUS response to the treatment. The peak enhancement (PE), perfusion index (PI), and area under the curve (AUC) were measured for the control and AOM treatment groups. The AOM group showed a substantial decrease in these parameters compared to the control group. The difference between the pre- and post-therapy was significant, (p < 0.001) for the AOM group and not significant (p > 0.5) for the control group. Tumor temperatures increased markedly for the AOM group with a thermal dose (CEM43) of 124.8 (±2.5). Histochemical analysis of the excised HCC samples revealed several hemorrhagic pools in tumors from the AOM group, absent in the tumors of the control group. These results demonstrate the theranostic potential of the AOM to induce and monitor vascular disruption within murine tumors.

3-D modeling applications in ultrasound education: a systematic review.

Ultrasound offers a real-time 2-D view of structures within the human body. While many medical education programs have already dedicated a portion of their curriculum to ultrasound, others are concerned about cost, accessibility and limits to student practice. Student benefit may be affected by cognitive errors, which are in part owing to the mental heuristics required to visualize a 3-D structure by interpreting a 2-D image. A possible solution to eliminating subjectivity in ultrasound interpretation is the use of 3-D models to augment the traditional 2-D ultrasound experience. PubMed, Embase and Web of Science were searched for primary literature exploring relationships between 3-D modeling applications and their use in ultrasound education. The search and review process was guided by the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) checklist. Overall, 14 of the included 16 studies indicated a significant improvement in medical education of ultrasound with the intervention of 3-D modeling applications. This systematic review confirms that 3-D modeling applications benefit student learning in ultrasound education while illuminating the need for more research in this field.

Acetaminophen protects against iron-induced cardiac damage in gerbils.

There are few effective agents that safely remove excess iron from iron-overloaded individuals. Our goal was to evaluate the iron-removing effectiveness of acetaminophen given ip or orally in the gerbil iron-overload model. Male gerbils were divided into 5 groups: saline controls, iron-overloaded controls, iron-overloaded treated with ip acetaminophen, iron-overloaded treated with oral acetaminophen, and iron-overloaded treated with ipdeferoxamine. Iron dextran was injected iptwice/wk for 8 wk. Acetaminophen and deferoxamine treatments were given on Mondays, Wednesdays, and Fridays during the same 8 wk and continued for 4 wk after completion of iron-overloading. Echocardiograms were performed after completion of the iron-overloading and drug treatments. Liver and cardiac iron contents were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). Iron-overloaded controls had 232-fold and 16-fold increases in liver and cardiac iron content, respectively, compared to saline controls. In iron-overloaded controls, echocardiography showed cardiac hypertrophy, right and left ventricular distension, significant reduction in left ventricular ejection fraction (-22%), and fractional shortening (-31%) during systole. Treatments with acetaminophen (ip or oral) or deferoxamine (ip) were equally effective in reducing cardiac iron content and in preventing cardiac structural and functional changes. Both agents also significantly reduced excess hepatic iron content, although acetaminophen was less effective than deferoxamine. The results suggest that acetaminophen may be useful for treatment of iron-induced pathology.

Irreversible electroporation inhibits pro-cancer inflammatory signaling in triple negative breast cancer cells.

Low-level electric fields have been demonstrated to induce spatial re-distribution of cell membrane receptors when applied for minutes or hours. However, there is limited literature on the influence on cell signaling with short transient high-amplitude pulses typically used in irreversible electroporation (IRE) for cancer treatment. Moreover, literature on signaling pertaining to immune cell trafficking after IRE is conflicting. We hypothesized that pulse parameters (field strength and exposure time) influence cell signaling and subsequently impact immune-cell trafficking. This hypothesis was tested in-vitro on triple negative breast cancer cells treated with IRE, where the effects of pulse parameters on key cell signaling factors were investigated. Importantly, real time PCR mRNA measurements and ELISA protein analyses revealed that thymic stromal lymphopoietin (TSLP) signaling was down regulated by electric field strengths above a critical threshold, irrespective of exposure times spanning those typically used clinically. Comparison with other treatments (thermal shock, chemical poration, kinase inhibitors) revealed that IRE has a unique effect on TSLP. Because TSLP signaling has been demonstrated to drive pro-cancerous immune cell phenotypes in breast and pancreatic cancers, our finding motivates further investigation into the potential use of IRE for induction of an anti-tumor immune response in vivo.

Age-associated changes in hearts of male Fischer 344/Brown Norway F1 rats.

Aging is associated with left ventricular hypertrophy, dilatation, and fibrosis of the heart. The Fischer 344/Brown Norway F1 (F344/BNF1) rat is recommended for age-related studies by the National Institutes on Aging because this hybrid rat lives longer and has a lower rate of pathological conditions than inbred rats. However, little is known about age-associated changes in cardiac and aortic function and structure in this model. This study evaluated age-related cardiac changes in male F344/BNF1 rats using ECHO, gross, and microscopic examinations. Rats aged 6-, 30-, and 36-mo were anesthetized and two-dimensional ECHO measurements, two-dimensional guided M-mode, Doppler M-mode, and other recordings from parasternal long- and short-axis views were obtained using a Phillips 5500 ECHO system with a 12 megahertz transducer. Hearts and aortas from sacrificed rats were evaluated grossly and microscopically. The ECHO studies revealed persistent cardiac arrhythmias (chiefly PVCs) in 72% (13/18) of 36-mo rats, 10% (1/10) of 30-mo rats, and none in 6-mo rats (0/16). Gross and microscopic studies showed left ventricular (LV) dilatation, borderline to mild hypertrophy, and areas of fibrosis that were common in 36-mo rats, less evident in 30-mo rats, and absent in 6-mo rats. Aging was associated with mild to moderate decreases of LV diastolic and systolic function. Thus, male F344/BN F1 rats demonstrated progressive age-related (a) decline in cardiac function (diastolic and systolic indices), (b) LV structural changes (chamber dimensions, volumes, and wall thicknesses), and (c) persistent arrhythmias. These changes are consistent with those in humans. The noninvasive ECHO technique offers a means to monitor serial age-related cardiac failure and therapeutic responses in the same rats over designated time intervals.

Progression of renal damage in the obese Zucker rat in response to deoxycorticosterone acetate-salt-induced hypertension.

This study assessed the progression of renal damage in obese Zucker rats in response to deoxycorticosterone acetate (DOCA)-salt-induced hypertension. Renal damage was evaluated by light microscopy and urine analysis at weekly intervals during the developmental phase of DOCA-salt hypertension and once during the plateau phase 42 days after the onset of treatment. Decreased tubular function was evident by day 8, as indicated by a significant increase in urine N-acetyl-beta-D-glucosaminidase activity and glucose excretion. The tubular index, a measure of tubular damage, was significantly elevated by day 15 and continued to increase throughout the experiment. Glomerular damage, which was evident by day 8, was followed by increased urine albumin excretion by day 15. Only a few sclerotic renal glomeruli were apparent before the plateau phase; however, by day 42, approximately 50% of the glomeruli were sclerotic. Hyperplastic vascular changes were mild at day 8 and slowly increased in severity during the developmental phase. By day 42 the vascular changes were severe with some vessels so hyperplastic that their lumens were almost occluded. These findings show progressive changes in renal structure and function that begin as early as day 8 and increase progressively until severe changes are present at day 42, resulting in an end-stage

Increased sensitivity of the obese Zucker rat to deoxycorticosterone-salt-induced hypertension.

OBJECTIVE: The objective of this study was to test the hypothesis that obesity increases the sensitivity of rats to experimentally induced hypertension. DESIGN AND METHODS: To induce hypertension, unilaterally nephrectomized lean and obese Zucker rats were injected with 25 mg/kg of deoxycorticosterone acetate (DOCA) twice weekly for 5 weeks and given water containing 1% NaCl to drink. Unilaterally nephrectomized control rats were injected with vehicle and drank tap water. Systolic blood pressure (SBP) was measured by the tail cuff method. Renal histology and urinary albumin excretion were used to assess the effects of the experimental treatment on the kidney. RESULTS: Obese rats exhibited a significant rise in SBP at 4 days after the start of DOCA-salt treatment. In contrast, SBP of DOCA-treated lean rats was not significantly elevated from pretreatment measurements until day 22. Moreover, SBP was significantly higher during the plateau phase of blood pressure development in obese DOCA-salt treated rats (196 mmHg) than in correspondingly treated lean rats (150 mmHg). Both obesity and DOCA-salt treatment promoted glomerulosclerosis and mild tubulointerstitial damage in the kidney with DOCA-salt treatment exacerbating the effect of obesity. Urinary albumin excretion was significantly greater in obese control rats compared with lean controls and in DOCA-treated obese rats relative to vehicle-treated obese rats. CONCLUSION: Results of this study indicate that obese Zucker rats are more sensitive to mineralocorticoid-induced hypertension than lean rats. This study provides experimental evidence supporting the epidemiological findings that obesity is a risk factor for the development of hypertension.

Acetaminophen combinations protect against iron-induced cardiac damage in gerbils.

This study tested if acetaminophen, N-methyl-D-glucamine dithiocarbamate (NMGDTC), deferoxamine, and combinations of these agents reduce excess iron content, prevent iron-induced pathology, reduce cardiac arrhythmias, and reduce mortality in iron-overloaded gerbils. Eight groups of 16 gerbils received iron dextran injections (ferric hydroxide dextran complex, 120 mg/kg, ip) or saline solution (controls) twice/wk for 8 wk. The 8 groups were treated every Monday, Wednesday, and Friday with one of the following: saline control, acetaminophen, 150 mg/kg, ip), acetaminophen (150 mg/kg, po), deferoxamine, 83 mg/kg, ip), NMGDTC (200 mg/kg, ip), or combinations of acetaminophen (75 mg/kg) with deferoxamine (42 mg/kg, each ip, separately) or acetaminophen (75 mg/kg) with NMGDTC (100 mg/kg, each ip, separately). The treatments were given 4 hr after each iron injection on days when both iron administration and treatment occurred during iron overloading (8 wk) and were continued 4 wk thereafter. Echocardiography (ECHO) was used to evaluate iron-induced cardiac changes and detect arrhythmias. Acetaminophen and NMGDTC, or combinations thereof, reduced cardiac and hepatic excess iron content as measured by inductively coupled plasma atomic emission spectrometry (ICP-AES). Acetaminophen was effective whether administered po or ip. Acetaminophen treatment had a positive inotropic effect on cardiac function. Acetaminophen-deferoxamine combination conferred equal cardioprotection as acetaminophen or deferoxamine alone, was equally able to remove hepatic iron, and was superior to either acetaminophen or deferoxamine in removing cardiac iron from iron-overloaded gerbils. Acetaminophen-NMGDTC combination was also effective in removing cardiac and hepatic iron and protecting against iron-induced cardiac damage. ECHO evaluation of iron-overloaded, untreated gerbils demonstrated a high incidence of cardiac arrhythmias, usually PVCs (10/16 = 63%), and mortality prior to completion of the experiment (4/16 = 25%). All treatments except deferoxamine, alone, reduced the incidence of cardiac arrhythmias and deaths. All treatments reduced iron-induced increases in hepatic and cardiac weights. This study demonstrates injection alternates that are equally or more effective than deferoxamine injections and shows oral acetaminophen to be effective in treatment of iron-overload and associated cardiac complications.

A moderately high fat diet promotes salt-sensitive hypertension in obese zucker rats by impairing nitric oxide production.

The objective of this research was to examine the contribution of a moderately high fat (MHF) diet to the development of salt-sensitive hypertension in obese Zucker rats. Lean and obese Zucker rats were fed either a MHF diet or a diet of standard rat chow (control diet) for 10 weeks. From week 4 through week 10, the drinking water was supplemented with 1% NaCl. Blood pressure was measured weekly, and urinary excretion of nitric oxide metabolites (NO(x)) was determined at weeks 4 and 10. At week 10, renal nitric oxide synthase (NOS) activity was assessed in kidney homogenates. Blood pressures of obese, but not lean, rats on the MHF fat diet were significantly increased by salt-supplementation, whereas blood pressures of rats on the control diet were not appreciably affected. NO(x) excretion was increased in response to salt-supplementation in rats on the control diet, with the effect being particularly dramatic in obese rats. After salt-supplementation, NO(x) excretion by rats on the MHF diet was lower than rats on the control diet. In obese rats on the MHF diet, this decrease in NO production was accompanied by a reduction in renal NOS activity. These results indicate that obese rats are more inclined than lean rats to develop diet-induced hypertension in response to a moderately high fat, salt-supplemented diet. Furthermore, they suggest that MHF diet-induced defects in NO production may promote the salt-sensitivity of blood pressure in obese Zucker rats, which appear to require more NO to maintain blood pressure during a salt challenge.