Use of a pocket-sized ultrasound machine (PUM) for routine examinations in the third trimester of pregnancy

Evaluating the accuracy and reliability of non-piezo portable ultrasound devices in postpartum care

INTRODUCTION

The early diagnosis of hemorrhage via postpartum ultrasound is crucial to initiate therapy and, thus, prevent maternal death. In these critical situations rapid availability and simple transport of ultrasound devices is vital, paving the way for a  new generation of portable handheld ultrasound devices (PUD) consisting of transducers and tablets or smart phones. However, evidence to confirm the diagnostic accuracy of these new devices is still scarce.

METHODS

The accuracy and reliability of these new devices in relation to established standard ultrasound devices is analyses in this pilot study by comparing diagnoses and by applying statistical analysis via Bland-Altman plots, intraclass correlation coefficients (ICC), and Pearson correlation coefficients (PCC). One hundred patients of a university hospital were included in this study.

RESULTS

In all cases, the same diagnosis was made regardless of the applied ultrasound device, confirming high accuracy. There was a high correlation (PCC 0.951) and excellent agreement (ICC 0.974) in the assessment of the cavum, while the assessment of the diameters of the uterus showed only a good correlation and a good agreement. Subgroup analysis for maternal weight, mode of delivery and day after delivery was performed  CONCLUSION: The same diagnosis independent of the used devices and excellent results of the cavum assessment promote the use of PUDs in a clinical setting. The slightly lower accuracy in the measurement of the uterus may be caused by the PUD's small acoustic window, reflecting one of its weaknesses. Therefore, the patient may benefit from the short time to diagnosis and the unbound location of examination, either in the delivery room, on the ward, or at home.

Medical student training with next-generation handheld ultrasound devices - hands on examination of fetal biometry in obstetrics

INTRODUCTION

The technical development of ultrasound devices based on silicon chips has revolutionized ultrasound examinations, leading to the implementation of these portable handheld devices (PUD) in different medical fields. However, training on these devices is necessary to assure appropriate use and ensure valid results. While training programs for the use of conventional standard ultrasound devices (SUD) have been described, no training program for these handheld devices has been developed thus far.

METHODS

A training program for obstetric ultrasound examination was modified through the addition of an extra module focusing on the use of these PUDs. After the module the students had to attend an OSCE in which their skills of using the PUD and the SUD were tested and analyzed by applying the agreement rate, the intraclass correlation coefficient (ICC) and Bland-Altman plots. Furthermore, the students' ultrasound results were compared with those of trained physicians by employing the one-sample Student's t-test. After the OSCE, the students answered a survey regarding their experience and their expected use of these devices.

RESULT

An agreement of one hundred percent was reached for basic parameters such as fetal position, placental position, fetal heartbeat and for the classification of the amniotic fluid. The ICC showed a good to moderate agreement between the results of fetal biometry achieved by SUD and PUD. The T-test results confirmed a high reliability between the physicians' results and the students' results, independent of the used device. The students remarked a good handling of the ultrasound devices and supported the use in their future specialties.

DISCUSSION

The reliability between the examinations using the SUD and PUD were high but lower than the results observed for trained physicians. Therefore, the implementation of an additional module for portable ultrasound teaches the students to reliably examine basic obstetric parameters and provides a solid basis for further training and improvement of ultrasound skills in use of PUD.

Diagnoses of postpartum urinary retention using next-generation non-piezo ultrasound technology: assessing the accuracy and benefits

Postpartum urinary retention has a wide range of publicized incidences, likely caused by frequent misdiagnosis of this puerperal complication. Especially covert postpartum urinary retention has a high number of missed diagnoses due to the lack of symptoms and the time-extensive diagnostics via ultrasound, leading to no treatment and no appropriate follow-up. To simplify the diagnosis and establish a screening tool we analyzed the application of portable handheld-ultrasound devices  (PUD) as used in Point-of-care diagnostics in comparison to established standard ultrasound devices (SUD). This prospective study aimed to evaluate the reliability of non-piezo, chip-based PUD in comparison to the measurement withSUD, containing a piezo transducer, as golden standard for the ultrasound diagnosis of postpartum urinary retention. Randomly, 100 participants between the first and seventh day after delivery in an obstetric ward underwent ultrasound examinations using a EPIQ 5 W (Philips) as SUD and a Butterfly iQ (Butterfly Network) as PUD to compare the accuracy in bladder size after micturition and the estimated post-void residual volume. Intraclass correlation coefficients, Bland-Altman plots, and Pearson correlation coefficients were used for analyzing the reliability and agreement between the measurements of these devices and were calculated for subgroups as body mass index, mode of delivery and timepoint of delivery. The results show a near-perfect agreement (0.994) and correlation (r = 0.982) for estimated post-void residual volume and for most measurements between the two types of ultrasound devices. The agreement rate for the diagnosis of covert postpartum urinary retention is 100%. Subgroup analyses lack a significant difference reflected by agreement and correlation rates. These findings affirm the high reliability of PUD for the diagnosis of postpartum urinary retention and supports their integration into daily clinical practice, thereby simplifying regular controls of the bladder by physicians during daily rounds on the ward. This technology may allow a higher diagnosis rate so that patient care can be optimized and the long-term impact on continence and quality of life can be studied and analysed.

The Potential of Tele-Ultrasound, Handheld and Self-Operated Ultrasound in Pregnancy Care: A Systematic Review

OBJECTIVE

To explore the use of tele-ultrasound and handheld or self-operated ultrasound in pregnancy.

METHODS

A systematic search provided 31 studies. The risk of bias for each study was assessed. Results were analyzed and presented in a narrative overview in four domains: tele-ultrasound, patient-operated ultrasound, handheld devices and low- and middle-income countries (LMIC).

RESULTS

The quality of studies was generally low or fair based on the NIH Quality Assessment Tools. Fetal tele-ultrasound services (11 studies) are feasible and especially helpful in rural areas or with increased centralization of specialist care. Three studies with patient-operated ultrasound concluded its feasibility with good-to-high experiences. The use of handheld devices in pregnancy (eight studies) showed similar ultrasound results when compared to standard devices. In LMICs, innovative use of ultrasound (nine studies) can facilitate access to obstetric care performed by trained as well as unskilled caregivers combined with remote evaluation by an expert.

CONCLUSIONS

Innovations in ultrasound in pregnancy care have shown promising results for application. Although most studies demonstrated benefits for pregnant women or care providers, high-level evidence is scarce. High-quality studies on innovations are needed to assess medical outcomes, patient and provider experiences and costs.

Next-generation monitoring in obstetrics: Assessing the accuracy of non-piezo portable ultrasound technology

INTRODUCTION

The emergence of handheld ultrasound devices capable of connecting to cell phones or tablets heralds a significant advancement in medical technology, particularly within the field of obstetrics. These devices offer the promise of immediate bedside ultrasound examinations, potentially revolutionizing patient care by enabling fetal assessments in diverse settings.

MATERIAL AND METHODS

This prospective study aimed to validate the reliability of non-piezo, chip-based handheld ultrasound devices in clinical obstetric practice. Conducted in a university hospital obstetric ward, the study included 100 pregnant women between 17 and 41 weeks of gestation. Participants underwent ultrasound examinations using both conventional and portable point-of-care ultrasound (POCUS) devices to compare the accuracy in estimating fetal weight and other parameters, such as cardiac activity, fetal presentation, placental location, and amniotic fluid volume. The reliability and agreement between the devices were assessed using intraclass correlation coefficients, Bland-Altman plots, and Pearson correlation coefficients.

RESULTS

The results show a near-perfect agreement (0.98) and correlation (r = 0.98, p < 0.001) for estimated fetal weight and most biometry measurements between the two types of ultrasound devices, with slight deviations in head circumference and amniotic fluid index measurements. Subgroup analysis revealed variations in agreement and correlation rates with higher BMI and advanced gestational age, indicating areas for further refinement.

CONCLUSIONS

These findings affirm the high reliability of handheld ultrasound devices for basic obstetric ultrasound evaluations, supporting their integration into daily clinical practice. This technology improves the flexibility and immediacy of prenatal care, although further research is needed to optimize its application across patient populations and treatment settings.

A review of robot-assisted ultrasound examination: Systems and technology

BACKGROUND

At present, the number and overall level of ultrasound (US) doctors cannot meet the medical needs, and the medical ultrasound robots will largely solve the shortage of medical resources.

METHODS

According to the degree of automation, the handheld, semi-automatic and automatic ultrasound examination robot systems are summarised. Ultrasound scanning path planning and robot control are the keys to ensure that the robot systems can obtain high-quality images. Therefore, the ultrasound scanning path planning and control methods are summarised. The research progress and future trends are discussed.

RESULTS

A variety of ultrasound robot systems have been applied to various medical works. With the continuous improvement of automation, the systems provide high-quality ultrasound images and image guidance for clinicians.

CONCLUSION

Although the development of medical ultrasound robot still faces challenges, with the continuous progress of robot technology and communication technology, medical ultrasound robot will have great development potential and broad application space.

Physicians' perceptions of the daily use of a handheld ultrasound device in the labor room

OBJECTIVE

The objective of our study was to describe the perception of physicians who use a handheld ultrasound (US) device in an intensive perinatal care unit.

METHODS

We conducted a prospective observational study in the labor ward of an intensive perinatal care unit between November 2021 and May 2022. Obstetrics & Gynecology residents in rotation in our department during this time were recruited as participants in this study. All the participants were provided with a handheld US device Vscan Air™ (GE Healthcare, Zipf, Austria) to use during their normal days and nights practice in labor ward. At the end of their 6 months rotation, participants completed an anonymous surveys about their perceptions of the handheld US device. The survey included questions about the ease of use in clinical situations, the amount of time of initial diagnosis, performances of the device, feasibility to use, and patient's satisfaction with the use of the device.

RESULTS

6 residents in their last year of residency were included. All the participants were satisfied with the device and would like to use it in their future practice. They all agreed that the probe was easy to handle and that the mobile application was easy to use. Image quality was always considered good by the participants and 5/6 of them declared that the handheld US device was always sufficient and did not require any confirmation with a conventional US machine. 5/6 of the participants considered that the handheld US device allowed them to gain time for clinical decision but half of them did not estimate that the use of the handheld US device improved their ability to make a clinical diagnosis.

CONCLUSION

Our study suggests that the Vscan Air™ is easy to use, with a good quality image and reduces the amount of time to make a clinical diagnosis. Handheld US device could be useful in the daily practice in maternity hospital.

Portable ultrasound technologies for estimating gestational age in pregnant women: a scoping review and analysis of commercially available models

OBJECTIVES

To identify all available studies assessing the use of portable ultrasound devices for pregnant women, with the specific aim of finding evidence for devices used to determine gestational age and their validity when compared with conventional ultrasound machines. We also wanted to determine what portable ultrasound models are commercially available for obstetric use.

DESIGN

Systematic scoping review.

PRIMARY AND SECONDARY OUTCOME MEASURES

Extracted variables included study design, population, method of ultrasound measurement, devices used and whether studies formally validated accuracy against conventional ultrasound.

RESULTS

We searched four databases-Medline, Embase, CINAHL and Maternal and Infant Care. In total 56 studies from 34 countries were identified; most were observational studies. Across all studies, 27 different portable ultrasound models (from 17 manufacturers) were evaluated. Twenty-one studies assessed use of portable ultrasound for evaluating fetal characteristics or estimating gestational age, and 10 of these were formal validation studies. In total, six portable devices have been validated for gestational age estimation against a conventional ultrasound comparator. The web searches identified 102 portable devices (21 manufacturers). These were a mix of handheld devices that connected to a phone or computer, or laptop-style portable ultrasound devices. Prices ranged from US$1190 to US$30 000 and weight ranged from 0.9 kg to 13.0 kg.

CONCLUSION

While the number of commercially available portable ultrasound devices continues to grow, there remains a lack of peer-reviewed, quality evidence demonstrating their accuracy and validity when compared with conventional ultrasound machines. This review identified some models that may be useful in gestational age estimation in low-resource settings, but more research is required to help implement the technology at scale.

TRIAL REGISTRATION NUMBER

Registered via Open Science Framework (DOI: 10.17605/OSF.IO/U8KXP).

Incorporating personal-device-based point-of-care ultrasound into obstetric care: a validation study

BACKGROUND

Personal-device-based point-of-care-ultrasound (P-POCUS) probes plug directly into a cell phone or tablet to function as its display, creating the potential to increase access to obstetric ultrasonography in complex healthcare settings (COVID units, low resource settings); however, new technology must be proven to be reliable in the obstetric setting before integrating into practice.

OBJECTIVE

To evaluate the intraclass correlation (reliability) of personal-device-based-point-of-care-ultrasound devices as compared with standard ultrasound machines in obstetrics.

STUDY DESIGN

This was a prospective, observational study of patients between 19-39 weeks gestation in an urban, prenatal ultrasound diagnosis center. Each patient underwent assessment by an expert sonographer using standard ultrasound machines and personal-device-based-point-of-care-ultrasound devices to determine estimated fetal weight. The statistical reliability and agreement between the estimated fetal weights was assessed through intraclass correlation coefficients, Bland-Altman plots, and Pearson correlation coefficients.

RESULTS

100 paired sets of scans were performed from October 2020 to December 2020. For the estimated fetal weights, there was near-perfect agreement, with an intraclass correlation coefficient of 0.99 (P<.0001). Bland-Altman analysis showed an average difference of 53 grams, with 95% limit of agreement between -178 grams and 283 grams. Pearson correlation showed near-perfect correlation between the measurements (r=0.99, P<.0001).

CONCLUSION

personal-device-based point-of-care-ultrasound devices are reliable tools for performing basic obstetrical ultrasound and have the potential to increase access to obstetrical ultrasound worldwide.

Point-of-care ultrasound in obstetrics and gynecology

BACKGROUND

The rapid technical development and portability of ultrasound systems over recent years has had a profound impact on the area of point-of-care-ultrasound (POCUS), both in general medicine and in obstetrics and gynecology. The use of POCUS enables the clinician to perform the ultrasound scan either at the medical office or the patient's bedside and used as an extension of the physical examination. Real-time images can immediately be correlated with the patient's symptoms, and any changes in a (critical) patient's condition can be more rapidly detected.

POCUS IN OBGYN

POCUS is also suitable for time-critical scenarios, and depending on the situation and its dynamics, the course and results of any therapy may be observed in real time. POCUS should be considered to be a routine extension of practice for most OB/GYN clinicians as it can give immediate answers to what could be life-threatening situations for the mother and/or baby. With its proven usefulness, the applications and use of POCUS should be incorporated in teaching programs for medical students, OBGYN residents and emergency physicians.

Evaluating sensitivity and specificity of handheld point-of-care ultrasound testing for gynecologic pathology: a pilot study for use in low resource settings

BACKGROUND

Point-of-care ultrasound (POC-US) is a diagnostic test conducted at the site of patient care with direct interpretation by the clinician, providing immediate results. POC-US for gynecologic application is not well characterized by current literature yet has the potential to increase access in limited resource settings. We compared the diagnostics of three POC-US devices for gynecologic (GYN) pathology and then performed evaluation of sensitivity and specificity of a single best POC-US device for intended use in a low resource setting.

METHODS

This is prospective, pilot descriptive study of 60 subjects. In part 1, comparison of three POC-US devices was performed. Twenty subjects underwent POC-US with three test units [GE Vscan (Vscan), Sonosite Iviz (Iviz), Philips Lumify (Lumify)] followed by diagnostic ultrasound (Dx-US) for reference imaging. Image quality and correlation for devices was scored by blinded reviewers and quantitative measurements of GYN pathology were compared. In part 2, forty subjects underwent POC-US validation with the highest scoring device (Lumify) and Dx-US for reference imaging. Concordance of POC-US operator-interpreted diagnosis with reference imaging interpretation were assessed by Cohen's unweighted kappa coefficient. Accuracy and agreement of POC-US were assessed by linear regression and Bland-Altman plot analysis. Sensitivity and specificity of POC-US for gynecologic pathologies were calculated.

RESULTS

In aggregate qualitative measurements, Lumify and Iviz units performed superiorly to Vscan. There was no statistically significant difference in quantitative measurements between devices, but a trend towards lower mean error was seen for Lumify and Iviz as compared to Vscan. Lumify device had highest overall scoring and was selected for further testing. In validation comparison of Lumify to Dx-US, no statistically significant differences were found for measurements of endometrium, uterus, ovaries, adnexal pathology, or leiomyomata, (P < 0.02) with excellent agreement in operator-interpreted diagnosis (Kappa > 0.7). Sensitivity and specificity of detecting pathology was 80-100% with PPV and NPV 76-100%.

CONCLUSION

Among three POC-US devices, Lumify and Iviz devices show highest potential for successful application to clinical gynecologic ultrasound. Clinician-performed POC-US has high diagnostic accuracy, sensitivity, and specificity for basic GYN anatomy and pathology. POC-US is an acceptable and feasible diagnostic tool with potential for future application in a low resource setting to increase access to ultrasound.

Hand-Held Ultrasound Devices Compared with High-End Ultrasound Systems: A Systematic Review

The aim of this study was to review the scientific literature available on the comparison of hand-held ultrasound devices with high-end systems for abdominal and pleural applications. PubMed, Embase, Web of Science and Cochrane were searched following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Original research describing hand-held ultrasound devices compared with high-end systems was included and assessed using Quality Assessment of Diagnostic Accuracy Studies (QUADAS)-2. The search was limited to articles published since 1 January 2012. A total of 2486 articles were found and screened by title and abstract. A total of 16 articles were chosen for final review. All of the included articles showed good overall agreement between hand-held and high-end ultrasound systems. Strong correlations were found when evaluating ascites, hydronephrosis, pleural cavities, in detection of abdominal aortic aneurysms and for use with obstetric and gynaecological patients. Other articles found good agreement for cholelithiasis and for determining the best site for paracentesis. QUADAS-2 analysis suggested few risks of bias and almost no concerns regarding applicability. For distinct clinical questions, hand-held devices may be a valuable supplement to physical examination. However, evidence is inadequate, and more research is needed on the abdominal and pleural use of hand-held ultrasound with more standardised comparisons, using only blinded reviewers.

Color Doppler Ultrasonography to Evaluate Hypoechoic Areas in Pressure Ulcers: A Report of Two Cases

Ultrasound (US) is frequently used for evaluating inflammation of subcutaneous tissue caused by pressure ulcers (PUs), but color Doppler mode (CDM) helps to better identify inflammatory edema in subcutaneous fat and necrotic tissue in PUs. We report two cases where inflammatory edema in subcutaneous fat and necrotic tissue in PUs are identified using small US equipment with CDM. Case 1 – An 82-year-old male presented with cerebral infarction and a Category III PU in the sacral region. B-mode gray-scale US imaging (B-mode imaging) revealed a thickened layer of subcutaneous fat with fat lobules and homogeneous cobblestone appearance with fluid accumulation within the echo-free space. CDM did not identify any color signal (CS) in hypoechoic areas. Case 2 – A 29-year-old female presented with cytopenia and decreased renal function with a Category IV PU with undermining in the coccyx region. B-mode imaging distinguished the necrotic tissue, indicating a diffuse hypoechoic area with no layers, unclear borders, and uneven gray level (cloud-like image) in the subcutaneous fat. Similar B-mode imaging findings were obtained in inflammatory edema with cobblestone appearance. CDM did not detect a CS in the hypoechoic areas but confirmed peripheral hypervascularity. CDM imaging identified inflammatory edema in the subcutaneous fat and necrotic tissue in PUs. Specifically, CDM may better evaluate early-stage PUs with necrotic tissue by distinguishing necrosis from intense inflammatory edema.

A futuristic vision of pocket ultrasound machines: watch this space

Introduction: Australian medical ultrasound started in 1959 with the establishment of the Ultrasonics Institute. Since then the technology has advanced tremendously. We are now not only able to obtain clearer images on high specification ultrasound machines but also on pocket-sized ultrasound machines that are compact, lightweight and affordable. Method: The following descriptive review will examine the indication for use of pocket ultrasound machines in different clinical settings as well as provide evidence of its image clarity and accuracy. Potentially eligible studies were sought primarily through searches of the electronic databases PubMed, Medline (1996-Present), Embase (1996-Present) and Cochrane Library. Conclusion: Pocket ultrasound machines, with appropriate ultrasound knowledge and training, can be incorporated successfully in patient management. The addition of point-of-care ultrasound has been shown to improve management recommendations and outcomes.