Assessing The Performance Characteristics of Handheld Ultrasound In A Rheumatic Heart Disease Screening Program

Background: Rheumatic heart disease affects 33 million people in low and middle income countries and is the leading cause of cardiovascular death among children and young adults. Penicillin prophylaxis has been shown to improve valvular function among patients with clinically silent or mild disease. Efforts to expand echocardiographic screening are focusing on simplified protocols, non-physician ultrasonographers, and portable ultrasound devices, including handheld ultrasound. Recent advances support the use of single-view screening protocols. With the increasing availability and low cost of handheld devices, prospective studies are needed to evaluate their performance in these settings. Methods: We conducted a cross-sectional pilot study among 19 at-risk school-children participating in a rheumatic heart disease screening program in Ethiopia comparing a handheld ultrasound device (Phillips Lumify) to a fully-equipped portable ultrasound machine (Sonosite M-Turbo). Results: Agreement between devices was similar for expert and non-expert review (84%). However, when reviewed by a non-expert the Lumify identified fewer screen-positive cases (p-value 0.083). We also compared non-expert to expert interpretation by device and found a significant difference in interpretation for the Lumify (p-value 0.025). There was a trend towards shorter jet length by color Doppler in the handheld ultrasound device for both expert and non-expert review. Conclusions: Our study highlights that screening echocardiograms for RHD may yield different results when a handheld ultrasound device is used.

Performance of an automated ultrasound device in identifying and tracing the heart in porcine cardiac arrest

Background While intra-arrest echocardiography can be used to guide and monitor chest compression quality, it is not currently feasible on the scene of out-of-hospital cardiac arrests. Rapid and automated sonographic localization of the heart may provide first-responders guidance to an optimal area of compression without requiring them to interpret ultrasound images. In this proof-of-concept porcine study, we sought to describe the performance of an automated ultrasound device in correctly identifying and tracing the borders of the heart in three distinct states: pre-arrest, arrest, and late arrest. Methods An automated ultrasound device (bladder scanner) was placed on the chests of 7 swine, along the left sternal border (4th–8th intercostal spaces). Scanner-generated images were recorded for each space during pre-arrest, arrest, and finally late arrest. 828 images of the LV and LV outflow tract were randomized and 150 (50/state) selected for analysis. Scanner tracings of the heart were then digitally obscured to facilitate tracing by expert reviewers who were blinded to the physiologic state. Reviewer tracings were compared to bladder scanner tracings; with concordance between these images determined via Sørensen–Dice index (SDI). Results When compared to human reviewers, the bladder scanner was able to identify and trace the borders during cardiac arrest. The bladder scanner performed best at the time of arrest (SDI 0.900 ± 0.059). As resuscitation efforts continued and time from initial arrest increased, the scanner’s performance decreased dramatically (SDI 0.597 ± 0.241 in late arrest). Conclusion An automated ultrasound device (bladder scanner) reliably traced porcine hearts during cardiac arrest. It is possible a device could be developed to indicate where compressions should be performed without requiring the operator to interpret ultrasound images. Further investigation into rapid, automated, sonographic localization of the heart to identify the area of compression in out-of-hospital cardiac arrest is warranted.

Handheld Versus Conventional Ultrasound for Assessing Carotid Artery in Routine Volunteers

Objective: The study aimed to estimate the feasibility and accuracy of carotid intima-media thickness (CIMT) and hemodynamic parameters measurement in a handheld ultrasound device.Methods: Utilizing an ex vivo pig carotid artery sample, CIMT was measured with a handheld ultrasound and compared with histopathology. Then we performed a carotid ultrasound on 25 volunteers using a handheld ultrasound device and a conventional ultrasound system. After a week, these volunteers were scanned again by the same observer. Assessments of the max IMT, mean IMT and hemodynamic parameters (PSV, EDV, PI, RI, S/D, ACCEL, AT, TAMEAN) were compared. Intraclass correlation coefficient (ICC) was used to assess inter-device agreement. Repeatability and correlation of mean IMT were analyzed by Bland–Altman Plots and linear correlation analysis. Results: The mean IMT measured from the common carotid artery by handheld ultrasound showed good agreement (ICC=0.79) with conventional ultrasound. Furthermore, we obtained good repeatability and a consistent trend in the mean value of IMT before and after (r = 0.680, P < 0.01). In addition, the max IMT and the hemodynamic parameters (PSV, EDV, S/D, ACCEL, TAMEAN) showed moderate agreement (ICC=0.73, 0.52, 0.58, 0.70, 0.61, 0.51, respectively). The PI, RI and HR values were excellent agreement with conventional ultrasound (ICC=0.80, 0.84, 0.94). Conclusion: About the basic assessment of carotid, the images and parameters obtained using handheld ultrasound showed a moderate to excellent agreement with conventional ultrasound. The handheld ultrasonic devices can be widely used as a diagnostic tool for carotid artery structure and hemodynamics examination.

Sonographic Evaluation of Gastric Residual Volume during Enteral Nutrition in Critically Ill Patients Using a Miniaturized Ultrasound Device

Background: To assess the risk of aspiration, nutrient tolerance, and gastric emptying of patients in ICUs, gastric ultrasound can provide information about the gastric contents. Using established formulas, the gastric residual volume (GRV) can be calculated in a standardized way by measuring the gastric antrum. The purpose of this study was to determine the GRV in a cohort of enterally fed patients using a miniaturized ultrasound device to achieve knowledge about feasibility and the GRV over time during the ICU stay. The findings could contribute to the optimization of enteral nutrition (EN) therapy. Methods: A total of 217 ultrasound examinations with 3 measurements each (651 measurements in total) were performed twice daily (morning and evening) in a longitudinal observational study on 18 patients with EN in the interdisciplinary surgical ICU of Saarland University Medical Center. The measured values of the GRV were analyzed in relation to the clinical course, the nutrition, and other parameters. Results: Measurements could be performed without interrupting the flow of clinical care and without pausing EN. The GRV was significantly larger with sparsely auscultated bowel sounds than with normal and excited bowel sounds (p < 0.01). Furthermore, a significantly larger GRV was present when using a high-caloric/low-protein nutritional product compared to an isocaloric product (p = 0.02). The GRV at the morning and evening measurements showed no circadian rhythm. When comparing the first and last ultrasound examination of each patient, there was a tendency towards an increased GRV (p = 0.07). Conclusion: The GRV measured by miniaturized ultrasound devices can provide important information about ICU patients without restricting treatment procedures in the ICU. Measurements are possible while EN therapy is ongoing. Further studies are needed to establish gastric ultrasound as a management tool in nutrition therapy.

Multiparametric ultrasound in torsion of the testicular appendages: a reliable diagnostic tool?

Aim: Torsion of the testicular appendages represents the most common cause of an acute scrotum in prepubertal boys. Its sonographic appearances on gray-scale US and color Doppler US have already been presented in several studies. The aim of this analysis was to expand those already established techniques with strain elastography and thus present typical features of this entity on multiparametric US.Material and methods: Retrospective analysis of all patients presented to the urological department with an acute scrotum between January 2018 and July 2020 identified eleven patients 6-17 years old (mean, 11.1 years), discharged with the diagnosis torsion of the testicular appendages that were examined with a high-end ultrasound device. Results: On gray-scale US all patients showed a round lesion with heterogenous echotexture adjacent to the upper pole of the testis/epididymis with a diameter of 4 to 11.1 mm (mean, 7.7 mm). Scrotal skin thickening and a concomitant hydrocele were found in 9 (81.8%) and 7 (63.6%) cases, respectively. On color Doppler images, all torsed appendages were avascular and in 9 (81.8%) patients we observed hyperemia of the adjacent epididymis. Strain elastography showed increased tissue stiffness in all documented images.Conclusion: Torsion of the testicular appendages has a set of features on multiparametric US. Awareness of this features can facilitate diagnosis of torsion of the testicular appendages and reduce unnecessary surgicalscrotal exploration or unwarranted antibiotic treatment.