Do pocket-sized ultrasound machines have the potential to be used as a tool to triage patients in obstetrics and gynecology?

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.

Performance of a handheld point of care ultrasonography to assess IUD position compared to conventional transvaginal ultrasonography

OBJECTIVE

To compare the performance of the abdominal handheld point-of-care ultrasonography (POCUS) Butterfly-iQ to gold standard transvaginal ultrasonography (US) in identifying the position of intrauterine devices (IUDs) in the hands of a medical doctor specialised in ultrasonography.

METHODS

In this diagnostic accuracy study, a single operator conducted abdominal POCUS followed by conventional transvaginal US. Seventy patients utilising copper or hormonal IUDs were assessed between June 2021 and October 2022. IUDs were categorised as entirely within the uterine cavity or malpositioned. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were calculated for detecting malpositioned IUDs, with conventional US results serving as the reference standard. Concordance rate and Kappa coefficient were computed to assess the agreement between the two ultrasound modalities.

RESULTS

Among the 70 patients, 46 (65.7%) used copper IUDs, and 24 (34.3%) used hormonal IUDs. Conventional transvaginal US showed IUDs entirely within the uterine cavity in 56 (80%) patients and 14 (20%) IUDs were malpositioned. Of the 14 malpositioned IUDs seen by conventional US, POCUS identified 13 demonstrating a sensitivity of 92.9% (66.1-99.8). Of the 56 IUDs entirely within the uterine cavity shown by conventional US, only two cases were considered malpositioned by POCUS demonstrating a specificity of 96.4% (87.7-99.6). The concordance rate was 95.7%, and the Kappa value was 0.87 in differentiating between IUDs entirely within the uterine cavity and those that were malpositioned.

CONCLUSION

Abdominal POCUS using Butterfly-iQ, when administered by an imaging specialist, exhibited excellent performance in confirming IUDs entirely within the uterine cavity.

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.

Handheld transabdominal ultrasound, after limited training, may confirm first trimester viable intrauterine pregnancy: a prospective cohort study

OBJECTIVES

Handheld point-of-care abdominal ultrasound (POCUS) may be used by primary care physicians while vaginal ultrasound is limited to use in specialist care. We aimed to compare abdominal handheld ultrasound to vaginal ultrasound in determining first trimester viable intrauterine pregnancy and estimate gestational length.

DESIGN

Prospective cohort study.

SETTING

Gynaecologic outpatient clinic; women referred from GPs during early pregnancy. Handheld ultrasound using VscanExtend^® was performed by fourth-year medical students with limited training. Transvaginal ultrasound using high-end devices was performed by ordinary hospital staff.

SUBJECTS

Women in the first trimester of pregnancy referred for termination of pregnancy or with symptoms of early pregnancy complications.

MAIN OUTCOME MEASURES

Rate of confirming vital intrauterine pregnancy (visualizing foetal heart beats) and measurement of crown-rump length (CRL) using handheld abdominal versus vaginal ultrasound.

RESULTS

In all 100 women were included; 86 confirmed as viable intrauterine pregnancies and 14 pathological pregnancies (miscarriages/extrauterine pregnancies). Handheld abdominal ultrasound detected fetal heartbeats in 63/86 (73% sensitivity) of healthy pregnancies and confirmed lack of fetal heartbeats in all pathological pregnancies, total positive predictive value (PPV) 100% and total negative predictive value (NPV) 38%. From gestational week 7, handheld abdominal ultrasound confirmed vitality in 51/54 patients: PPV 100% and NPV 79%. CRL (n = 62) was median 1 mm shorter (95% confidence interval 1-2 mm) measured by handheld abdominal versus vaginal ultrasound.

CONCLUSION

Handheld ultrasound has an excellent prediction confirming viable intrauterine pregnancy from gestational week 7. Validation studies are needed to confirm whether the method is suitable in primary care assessing early pregnancy complications.KEY POINTSWhen early pregnancy vitality needs to be confirmed, women will traditionally be referred to secondary care for transvaginal comprehensive ultrasonography performed with high-end devices by imaging specialists.In this study personnel with limited former training (fourth-year medical students) performed transabdominal POCUS using a handheld device, investigating 100 first trimester pregnancies for confirmation of viability.Using handheld ultrasound viable pregnancy was confirmed from gestational week 7 with 79% positive and 100% negative predictive value.If handheld ultrasound used in primary care confirms vital intrauterine pregnancy, the need for specialist referral could be reduced.

Sporadic miscarriage: evidence to provide effective care

The physical and psychological effect of miscarriage is commonly underappreciated. The journey from diagnosis of miscarriage, through clinical management, to supportive aftercare can be challenging for women, their partners, and caregivers. Diagnostic challenges can lead to delayed or ineffective care and increased anxiety. Inaccurate diagnosis of a miscarriage can result in the unintended termination of a wanted pregnancy. Uncertainty about the therapeutic effects of interventions can lead to suboptimal care, with variations across facilities and countries. For this Series paper, we have developed recommendations for practice from a literature review, appraisal of guidelines, and expert group discussions. The recommendations are grouped into three categories: (1) diagnosis of miscarriage, (2) prevention of miscarriage in women with early pregnancy bleeding, and (3) management of miscarriage. We recommend that every country reports annual aggregate miscarriage data, similarly to the reporting of stillbirth. Early pregnancy services need to focus on providing an effective ultrasound service, as it is central to the diagnosis of miscarriage, and be able to provide expectant management of miscarriage, medical management with mifepristone and misoprostol, and surgical management with manual vacuum aspiration. Women with the dual risk factors of early pregnancy bleeding and a history of previous miscarriage can be recommended vaginal micronised progesterone to improve the prospects of livebirth. We urge health-care funders and providers to invest in early pregnancy care, with specific focus on training for clinical nurse specialists and doctors to provide comprehensive miscarriage care within the setting of dedicated early pregnancy units.

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.

Utility of gastrointestinal ultrasound in functional gastrointestinal disorders: A narrative review

Gastrointestinal (GI) ultrasound (GIUS) is valuable in the evaluation of GI diseases such as inflammatory bowel disease, but its use in functional GI disorders (FGIDs) is largely unknown although promising. In order to review the current knowledge on current and potential uses of GIUS in FGIDs, information was obtained via a structured literature search through PubMed, EMBASE and Google Scholar databases with a combination of MESH and keyword search terms: “ultrasound”, “functional GI disorders”, “irritable bowel syndrome”, “functional dyspepsia”, “intestinal ultrasound”, “point of care ultrasonography”, “transabdominal sonography”, “motility”, “faecal loading”, “constipation”. GIUS is currently used for various settings involving upper and lower GI tracts, including excluding organic diseases, evaluating physiology, guiding treatment options and building rapport with patients. GIUS can be potentially used to correlate mechanisms with symptoms, evaluate mechanisms behind treatment efficacy, and investigate further the origin of symptoms in real-time. In conclusion, GIUS is unique in its real-time, interactive and non-invasive nature, with the ability of evaluating several physiological mechanisms with one test, thus making it attractive in the evaluation and management of FGIDs. However, there are still limitations and concerns of operator dependence and lack of validation data for widespread implementation of GIUS in FGIDs.

Assessment of peripheral muscle thickness and architecture in healthy volunteers using hand-held ultrasound devices; a comparison study with standard ultrasound

BACKGROUND

Pocket-sized ultrasound devices are increasingly used in a variety of clinical situations, and perform well against standard ultrasound machines. We sought to investigate if a pocket-sized ultrasound device can assess muscle thickness and architecture in healthy volunteers.

METHODS

Healthy male volunteers (n = 21) across a range of ages were recruited to the study. Laying supine, ultrasound images were taken from the right anterior and lateral thigh. Thickness of the rectus femoris (RFMT), vastus intermedius (VIMT), and the two combined (anterior thigh, AMT) were measured, along with thickness of vastus lateralis (VLMT), pennation angle (VLPA) and derived fascicle length (VLFL). These scans were performed initially using a pocket-sized ultrasound (VScan) and then using a standard device (Telemed Echoblaster 128).

RESULTS

In all six variables, there was no significant difference between the two sets of measurements. Intra-class correlation co-efficients (ICC) for VLMT, VLPA, and AMT were all excellent (0.93, 0.89, 0.90 respectively) with the derived value of VLFL having an ICC of 0.84. All ICC values were statistically significant. Regression analysis demonstrated no evidence of proportional bias in any of the measured or derived variables.

CONCLUSION

A pocket-sized ultrasound device gives similar measurements of lower limb muscle thickness and architecture as a standard device in healthy volunteers.

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.

Comparison of a Pocket-Sized Versus a Full-Sized Ultrasound System in the Diagnosis of Proximal Lower Limb Acute Deep Vein Thrombosis

This study assessed the performance of a pocket-sized ultrasound system for the diagnosis of proximal lower limb acute deep vein thrombosis (DVT) compared to a full-sized ultrasound system. Patients who needed urgent lower limb sonograms for acute DVT were invited for the study. In each examination, the investigator scanned the patient using the pocket-sized system and then repeated the scan using the full-sized system. The sensitivity, specificity, and accuracy of the pocket-sized system were determined in reference to the full-sized system. The venous segments that failed to be visualized using the two systems were compared. One hundred lower limbs comprising 500 venous segments were examined. There were four venous segments, including two mid and two lower femoral veins in two patients who failed to be visualized using both systems. The sensitivity, specificity, and accuracy for diagnosing proximal lower limb acute DVT were 100% (95% confidence interval [CI], 94.94%–100%), 100% (95% CI, 99.05%–100%), and 100% (95% CI, 99.19%–100%), respectively. The pocket-sized ultrasound system and the full sized-ultrasound system demonstrated a comparable performance in detecting acute DVT in the leg.

Bedside screening with the use of pocket-size imaging device can be useful for ruling out carotid artery stenosis in patients scheduled for cardiac surgery

BACKGROUND

Patients (pts) scheduled for coronary artery bypass grafting, burdened with high risk of carotid stenosis, are recommended to undergo duplex ultrasonography (DUS) of carotid arteries.

PURPOSE

To validate pocket-size imaging device (PSID) equipped with linear probe as an easily accessible tool enabling bedside screening for carotid artery stenosis (CAS).

METHODS

A total of 100 pts (60 men, mean age 69±11 years) with multivessel coronary artery disease underwent bedside DUS of carotid arteries with the use of PSID performed by a cardiology resident trained in DUS. Subsequently, DUS with the use of stationary high-end ultrasound system was performed in all pts to verify findings of PSID examination.

RESULTS

Initial diagnosis of atherosclerotic plaque presence obtained with PSID in 59 patients was confirmed by high-end ultrasound system examination in all cases. There was a statistically significant correlation of intima-media thickness measurements between PSID and stationary system (r=.58; 95% CI: 0.48-0.66; P<.0001), but the coefficient of agreement (κ) between the two methods in classification of intima-media as normal or thickened (>0.9 mm) was only .38 (95% CI: 0.299-0.459). During PSID examination, turbulent flow was observed in 21 pts-CAS was confirmed in all these pts-5 pts were diagnosed with significant CAS, the rest with CAS ranging from 30% to 70%.

CONCLUSIONS

Pocket-size imaging device equipped with linear probe allows for identification of patients with atherosclerotic plaques and turbulent flow in carotid arteries; however, the degree of CAS cannot be reliably determined. The measurement accuracy of intima-media thickness is insufficient for a diagnostic purpose.

Point of Care Ultrasound: A WFUMB Position Paper

Over the last decade, the use of portable ultrasound scanners has enhanced the concept of point of care ultrasound (PoC-US), namely, "ultrasound performed at the bedside and interpreted directly by the treating clinician." PoC-US is not a replacement for comprehensive ultrasound, but rather allows physicians immediate access to clinical imaging for rapid and direct solutions. PoC-US has already revolutionized everyday clinical practice, and it is believed that it will dramatically change how ultrasound is applied in daily practice. However, its use and teaching are different from continent to continent and from country to country. This World Federation for Ultrasound in Medicine and Biology position paper discusses the current status and future perspectives of PoC-US. Particular attention is given to the different uses of PoC-US and its clinical significance, including within emergency and critical care medicine, cardiology, anesthesiology, rheumatology, obstetrics, neonatology, gynecology, gastroenterology and many other applications. In the future, PoC-US will be more diverse than ever and be included in medical student training.

Pocket ultrasound device as a complement to physical examination for ascites evaluation and guided paracentesis

The pocket ultrasound device (PUD) is a new tool that may be of use in the early detection of ascites. Abdominal ultrasound-guided paracentesis has been reported to decrease the rate of complications due to the procedure, but must be performed in a healthcare setting; this new tool may be a useful on an ambulatory basis. The aim of this study was to determine the diagnostic usefulness of the PUD in the diagnosis of ascites and the safety of guided paracentesis. We conducted a retrospective study that included adult patients suspected of having ascites and in whom an evaluation was performed with the PUD to identify it. Concordance with abdominal ultrasound (AUS) was determined with the Kappa coefficient. Sensitivity (Se), specificity (Sp) and likelihood ratios (LR) were determined and compared with physical examination, AUS, computed tomography and procurement of fluid by paracentesis. Complications resulting from the guided paracentesis were analyzed. 89 participants were included and 40 underwent a paracentesis. The PUD for ascites detection had 95.8 % Se, 81.8 % Sp, 5.27 +LR and 0.05 -LR. It had a concordance with AUS of 0.781 (p < 0.001). Technical problems during the guided paracentesis were present in only two participants (5 %) and three patients (7.5 %) developed minor complications that required no further intervention. There were no severe complications or deaths. This study suggests that the PUD is a reliable tool for ascites detection as a complement to physical examination and appears to be a safe method to perform guided paracentesis.

Pocket-size imaging devices allow for reliable bedside screening for femoral artery access site complications

The aim of this study was to validate pocket-size imaging devices (PSIDs) as a fast screening tool for detecting complications after femoral artery puncture. Forty patients undergoing femoral artery puncture for arterial access related to percutaneous coronary intervention were enrolled. Twenty-four hours after percutaneous coronary intervention, the involved inguinal region was assessed with PSIDs enabling 2-D gray-scale and color Doppler imaging. Subsequently, examination with a stationary high-end ultrasound system was performed to verify the findings of bedside examination in all patients. In 37 patients, PSID imaging had good diagnostic quality. False aneurysms (one asymptomatic) occurred in four patients, and all were recognized during bedside screening with PSID. One case of femoral artery thrombosis was confirmed with PSID and during standard ultrasonographic examination. Physical examination augmented with the quick bedside PSID examination had a sensitivity of 100% and specificity of 91%. PSID facilitated rapid bedside detection of serious access site complications in the vast majority of patients, including asymptomatic cases.

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.

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

OBJECTIVES

To evaluate the application of a pocket-sized ultrasound machine (PUM) in a routine antenatal third-trimester scan compared with a high-specification ultrasound machine (HSUM).

METHODS

This was an observational cohort study of 53 unselected women who came for their routine third-trimester ultrasound scan. The first scan was performed by an experienced ultrasonographer on an HSUM for fetal growth, fetal wellbeing and placental location. A second experienced operator performed the measurements on the PUM. Both operators were blinded to the other's findings and measurement results.

RESULTS

Fifty-one patients were eligible and scanned at a median gestational age of 31 + 1 (range, 27 + 2 to 36 + 0) weeks. Mean pregestational body mass index was 22.9 ± 3.1 (range, 17.6-35.7) kg/m(2) . In the comparison between measurements made using the PUM and HSUM, perfect agreement was found for fetal position, fetal bladder and stomach visualization (all κ 1.0) and very good agreement was found for placental position (κ 0.86). Measurements of deepest vertical pocket correlated moderately (intraclass correlation coefficient (ICC) 0.38 (95% CI, 0.12-0.59); Bland-Altman bias, 2.43 (95% limits of agreement (LoA), -22.65 to 27.51)). For fetal growth measurements there was very good agreement for biparietal diameter (ICC, 0.93 (95% CI, 0.88-0.96), Bland-Altman bias, -1.06 (95% LoA, -5.07 to 2.95)), and good agreement for femur length (ICC, 0.66 (95% CI, 0.48-0.79), Bland-Altman bias 0.56 (95% LoA, -5.97 to 7.08)) and transcerebellar diameter (ICC, 0.65 (95% CI, 0.46-0.78), Bland-Altman bias, -0.84 (95% LoA, -7.77 to 6.09)).

CONCLUSION

A battery-driven PUM can be used in third-trimester obstetrics for routine assessment of fetal growth (biparietal diameter, transcerebellar diameter and femur length) and for assessment of fetal wellbeing.