Microvascular imaging findings in infants with bacterial meningitis: a case series.

Bacterial meningitis is a severe and life-threatening disease that rapidly progresses in neonates and infants; prompt diagnosis and appropriate treatment are lifesaving. Magnetic resonance imaging remains the primary imaging technique for diagnosing meningitis; however, due to its limited availability and cost, ultrasound is often used for initial screening. Microvascular imaging ultrasound (MVI) is an emerging technique that offers insight into the brain microvasculature beyond conventional ultrasound. Here we present three patients with confirmed bacterial meningitis and associated cerebral microvascular findings on brain MVI to instigate further validation of cerebral microvascular imaging markers of bacterial meningitis for early detection and intervention.

The Acceptance and Use of Digital Technologies for Self-Reporting Medication Safety Events After Care Transitions to Home in Patients With Cancer: Survey Study.

BACKGROUND: Actively engaging patients with cancer and their families in monitoring and reporting medication safety events during care transitions is indispensable for achieving optimal patient safety outcomes. However, existing patient self-reporting systems often cannot address patients' various experiences and concerns regarding medication safety over time. In addition, these systems are usually not designed for patients' just-in-time reporting. There is a significant knowledge gap in understanding the nature, scope, and causes of medication safety events after patients' transition back home because of a lack of patient engagement in self-monitoring and reporting of safety events. The challenges for patients with cancer in adopting digital technologies and engaging in self-reporting medication safety events during transitions of care have not been fully understood. OBJECTIVE: We aim to assess oncology patients' perceptions of medication and communication safety during care transitions and their willingness to use digital technologies for self-reporting medication safety events and to identify factors associated with their technology acceptance. METHODS: A cross-sectional survey study was conducted with adult patients with breast, prostate, lung, or colorectal cancer (N=204) who had experienced care transitions from hospitals or clinics to home in the past 1 year. Surveys were conducted via phone, the internet, or email between December 2021 and August 2022. Participants' perceptions of medication and communication safety and perceived usefulness, ease of use, attitude toward use, and intention to use a technology system to report their medication safety events from home were assessed as outcomes. Potential personal, clinical, and psychosocial factors were analyzed for their associations with participants' technology acceptance through bivariate correlation analyses and multiple logistic regressions. RESULTS: Participants reported strong perceptions of medication and communication safety, positively correlated with medication self-management ability and patient activation. Although most participants perceived a medication safety self-reporting system as useful (158/204, 77.5%) and easy to use (157/204, 77%), had a positive attitude toward use (162/204, 79.4%), and were willing to use such a system (129/204, 63.2%), their technology acceptance was associated with their activation levels (odds ratio [OR] 1.83, 95% CI 1.12-2.98), their perceptions of communication safety (OR 1.64, 95% CI 1.08-2.47), and whether they could receive feedback after self-reporting (OR 3.27, 95% CI 1.37-7.78). CONCLUSIONS: In general, oncology patients were willing to use digital technologies to report their medication events after care transitions back home because of their high concerns regarding medication safety. As informed and activated patients are more likely to have the knowledge and capability to initiate and engage in self-reporting, developing a patient-centered reporting system to empower patients and their families and facilitate safety health communications will help oncology patients in addressing their medication safety concerns, meeting their care needs, and holding promise to improve the quality of cancer care.

Intravenous administration of ultrasound contrast to critically ill pediatric patients.

BACKGROUND: The off-label use of contrast-enhanced ultrasound has been increasingly used for pediatric patients. OBJECTIVE: The purpose of this retrospective study is to report any observed clinical changes associated with the intravenous (IV) administration of ultrasound contrast to critically ill neonates, infants, children, and adolescents. MATERIALS AND METHODS: All critically ill patients who had 1 or more contrast-enhanced ultrasound scans while being closely monitored in the neonatal, pediatric, or pediatric cardiac intensive care units were identified. Subjective and objective data concerning cardiopulmonary, neurological, and hemodynamic monitoring were extracted from the patient's electronic medical records. Vital signs and laboratory values before, during, and after administration of ultrasound contrast were obtained. Statistical analyses were performed using JMP Pro, version 15. Results were accepted as statistically significant for P-value<0.05. RESULTS: Forty-seven contrast-enhanced ultrasound scans were performed on 38 critically ill patients, 2 days to 17 years old, 19 of which were female (50%), and 19 had history of prematurity (50%). At the time of the contrast-enhanced ultrasound scans, 15 patients had cardiac shunts or a patent ductus arteriosus, 25 had respiratory failure requiring invasive mechanical oxygenation and ventilation, 19 were hemodynamically unstable requiring continual vasoactive infusions, and 8 were receiving inhaled nitric oxide. In all cases, no significant respiratory, neurologic, cardiac, perfusion, or vital sign changes associated with IV ultrasound contrast were identified. CONCLUSION: This study did not retrospectively identify any adverse clinical effects associated with the IV administration of ultrasound contrast to critically ill neonates, infants, children, and adolescents.

Improving sub-pixel accuracy in ultrasound localization microscopy using supervised and self-supervised deep learning.

With a spatial resolution of tens of microns, ultrasound localization microscopy (ULM) reconstructs microvascular structures and measures intravascular flows by tracking microbubbles (1-5 µm) in contrast enhanced ultrasound (CEUS) images. Since the size of CEUS bubble traces, e.g. 0.5-1 mm for ultrasound with a wavelength λ = 280 µm, is typically two orders of magnitude larger than the bubble diameter, accurately localizing microbubbles in noisy CEUS data is vital to the fidelity of the ULM results. In this paper, we introduce a residual learning based supervised super-resolution blind deconvolution network (SupBD-net), and a new loss function for a self-supervised blind deconvolution network (SelfBD-net), for detecting bubble centers at a spatial resolution finer than λ/10. Our ultimate purpose is to improve the ability to distinguish closely located microvessels and the accuracy of the velocity profile measurements in macrovessels. Using realistic synthetic data, the performance of these methods is calibrated and compared against several recently introduced deep learning and blind deconvolution techniques. For bubble detection, errors in bubble center location increase with the trace size, noise level, and bubble concentration. For all cases, SupBD-net yields the least error, keeping it below 0.1 λ. For unknown bubble trace morphology, where all the supervised learning methods fail, SelfBD-net can still maintain an error of less than 0.15 λ. SupBD-net also outperforms the other methods in separating closely located bubbles and parallel microvessels. In macrovessels, SupBD-net maintains the least errors in the vessel radius and velocity profile after introducing a procedure that corrects for terminated tracks caused by overlapping traces. Application of these methods is demonstrated by mapping the cerebral microvasculature of a neonatal pig, where neighboring microvessels separated by 0.15 λ can be readily distinguished by SupBD-net and SelfBD-net, but not by the other techniques. Hence, the newly proposed residual learning based methods improve the spatial resolution and accuracy of ULM in micro- and macro-vessels.

Personalization in digital health interventions for older adults with cancer: A scoping review.

INTRODUCTION: Digital health interventions (DHIs) are promising to support older adults with cancer in managing their conditions and improving their health outcomes. However, there is a lack of overall understanding of various DHIs for the aging population with cancer. Specifically, it is unclear how personalization components are included in those DHIs to promote engagement in the interventions among older adults with cancer. This study aimed to provide a comprehensive overview of existing DHIs for older adults with cancer and identify the intervention components, especially personalized features, and effectiveness of these DHIs for improving self-management and psychosocial health. MATERIALS AND METHODS: A scoping review was conducted following Joanna Briggs Institute guidelines, focusing on older adults diagnosed with cancer who participated in DHIs to improve self-management and psychosocial health. Studies using an experimental design and published from 2000 to January 2023 were retrieved from four databases: PubMed, Embase, CINAHL, and Scopus. After primary data extraction of study characteristics, participants, interventions, and outcomes, DHIs were categorized according to personalized features. RESULTS: Out of 9,750 articles, 20 were eligible for this scoping review. The main personalized features of DHIs were categorized into four domains: goal setting, adjusting the plan, data-driven approaches, and motivating behavioral changes. Self-management outcomes were focused on physical activity, diet, and symptom management. Quality of life, depression, and anxiety were addressed as psychosocial health-related outcomes. Although no consistent results were reported on the effectiveness, DHIs with a combination of multiple personalized features, more than three domains, were likely to be more effective in improving self-management outcomes. DISCUSSION: This review enhances the understanding of personalized DHIs for older adults with cancer by identifying intervention components, personalized features, and effectiveness on self-management and psychosocial health. Several gaps were identified, including the absence of targeted studies exclusively focusing on older adults, a relative scarcity of personalized features for improving patient engagement, a lack of understanding of the mechanism of effective personalized features, and the necessity for more experimental studies. Addressing these gaps can contribute to improving health outcomes and the quality of care for older adults with cancer by providing the direction for developing effective DHIs.

Cerebral Microvascular Imaging in Infants: Scan Technique and Potential Clinical Applications.

ABSTRACT: Brain ultrasound in infants, although widely utilized, provides limited functional insights into the brain. Although color and power Doppler ultrasounds have allowed quantitative assessment of cerebral macrovascular flow dynamics, there is no standardized tool integrated into the current neurosonography protocol that allows cerebral microvascular flow assessment. The evaluation of anatomic and functional changes in cerebral microvessels is important, as microvascular alterations have been shown to precede macrovascular and tissue injury in a variety of neurologic diseases of infancy. In this regard, the cerebral microvascular imaging technique is a commercially available, advanced Doppler technique in which slow flow of cerebral microvessels can be detected via a static noise suppression algorithm. This article therefore shares the basic scan technique and clinical examples of the integrated use of microvascular imaging in neurosonography for infants, setting the stage for future clinical integration of the technique.

A Template for Translational Bioinformatics: Facilitating Multimodal Data Analyses in Preclinical Models of Neurological Injury.

Background: Pediatric neurological injury and disease is a critical public health issue due to increasing rates of survival from primary injuries (e.g., cardiac arrest, traumatic brain injury) and a lack of monitoring technologies and therapeutics for the treatment of secondary neurological injury. Translational, preclinical research facilitates the development of solutions to address this growing issue but is hindered by a lack of available data frameworks and standards for the management, processing, and analysis of multimodal data sets. Methods: Here, we present a generalizable data framework that was implemented for large animal research at the Children's Hospital of Philadelphia to address this technological gap. The presented framework culminates in an interactive dashboard for exploratory analysis and filtered data set download. Results: Compared with existing clinical and preclinical data management solutions, the presented framework accommodates heterogeneous data types (single measure, repeated measures, time series, and imaging), integrates data sets across various experimental models, and facilitates dynamic visualization of integrated data sets. We present a use case of this framework for predictive model development for intra-arrest prediction of cardiopulmonary resuscitation outcome. Conclusions: The described preclinical data framework may serve as a template to aid in data management efforts in other translational research labs that generate heterogeneous data sets and require a dynamic platform that can easily evolve alongside their research.

Advanced Neuromonitoring Modalities on the Horizon: Detection and Management of Acute Brain Injury in Children.

Timely detection and monitoring of acute brain injury in children is essential to mitigate causes of injury and prevent secondary insults. Increasing survival in critically ill children has emphasized the importance of neuroprotective management strategies for long-term quality of life. In emergent and critical care settings, traditional neuroimaging modalities, such as computed tomography and magnetic resonance imaging (MRI), remain frontline diagnostic techniques to detect acute brain injury. Although detection of structural and anatomical abnormalities remains crucial, advanced MRI sequences assessing functional alterations in cerebral physiology provide unique diagnostic utility. Head ultrasound has emerged as a portable neuroimaging modality for point-of-care diagnosis via assessments of anatomical and perfusion abnormalities. Application of electroencephalography and near-infrared spectroscopy provides the opportunity for real-time detection and goal-directed management of neurological abnormalities at the bedside. In this review, we describe recent technological advancements in these neurodiagnostic modalities and elaborate on their current and potential utility in the detection and management of acute brain injury.

Brain Targeted Xenon Protects Cerebral Vasculature After Traumatic Brain Injury.

Abstract Cerebrovascular dysfunction following traumatic brain injury (TBI) is a well-characterized phenomenon. Given the therapeutic potential of xenon, we aimed to study its effects after localized delivery to the brain using microbubbles. We designed xenon-containing microbubbles stabilized by dibehenoylphosphatidylcholine (DBPC) and polyethylene glycol (PEG) attached to saturated phospholipid (DPSE-PEG5000). Using a pig model of TBI, these microbubbles were intravenously injected, and ultrasound was used to release xenon at the level of the carotid artery. The control group received perfluorobutane containing microbubbles. Diffusion tensor imaging (DTI) showed areas of higher fractional anisotropy for pigs receiving xenon microbubbles compared to the control group at 1 day after injury. Radial diffusivity analysis showed that this effect was mainly the result of acute edema. Pigs were euthanized at 5 days, and the brain tissues of xenon-treated animals showed reduction of perivascular inflammation and blood-brain barrier disruption. Endothelial cell culture experiments showed that glutamate reduces tight junction protein zona occludens-1 (ZO-1), but treatment with xenon microbubbles attenuates this effect. Xenon treatment protects cerebrovasculature and reduces astroglial reactivity after TBI. Further, these data support the future use of localized delivery of various therapeutic agents for brain injury using microbubbles in order to limit systemic side effects and reduce costs.

The effect of nurse-led digital health interventions on blood pressure control for people with hypertension: A systematic review and meta-analysis.

PURPOSE: Nurse-led digital health interventions (DHIs) for people with chronic disease are increasing. However, the effect of nurse-led DHIs on blood pressure control and hypertension self-management remains unclear. This study aimed to identify the characteristics of nurse-led DHIs for people with hypertension and compared the effect size of nurse-led DHIs with that of usual care to establish evidence for the development of effective nursing interventions using technologies. DESIGN: Systematic review and meta-analysis. METHODS: This systematic review and meta-analysis followed the Preferred Reporting Items for Systematic Reviews of Intervention (PRISMA) guidelines and registered the protocol in PROSPERO. Studies published from 2000 to August 5, 2021, were searched using the international databases: PubMed; Embase; Cochrane Central Register of Controlled Trials; Web of Science; CINAHL; Korean databases: RISS, KISS, KMBASE; and NDSL. Risk of bias 2.0 was used for evaluating the quality of studies. The primary outcome was blood pressure control. The secondary outcomes were self-management, medication adherence, and diet adherence. Publication bias was assessed using the funnel plot and Egger's regression tests. FINDINGS: The systematic review included 26 studies. A meta-analysis of 21 studies was conducted to calculate the effect size and identify heterogeneity among the included studies. In our meta-analysis, we observed that nurse-led DHIs reduced systolic blood pressure by 6.49 mmHg (95% confidence interval [CI]: -8.52 to -4.46, I2  = 75.4%, p < 0.05) and diastolic blood pressure by 3.30 mmHg (95% CI: -4.58 to -2.01, I2  = 70.3%, p < 0.05) when compared with usual care. Concerning secondary outcomes, the effect size on self-management, medication adherence, and diet adherence was 0.98 (95% CI: 0.58 to 1.37, I2  = 63.2%, p < 0.05), 1.05 (95% CI: 0.41 to 1.69, I2  = 92.5%, p < 0.05), and 0.80 (95% CI: 0.17 to 1.42, I2  = 80.5%, p < 0.05), respectively. CONCLUSION: Nurse-led DHIs were more effective in reducing blood pressure and enhancing self-management than usual care among people with hypertension. Therefore, as new technologies are being rapidly developed and applied in healthcare systems, further studies and policy support are needed to utilize the latest digital innovations with nursing interventions. CLINICAL RELEVANCE: This study could be used to identify that nurse-led interventions may take advantage of real-time communication by employing digital technologies for improving blood control and self-management behaviors such as medication adherence and diet adherence. Using nurse-led DHIs allows nurses to provide patient-centered interventions such as reflecting on patients' needs and shared decision-making without space constraints and limited treatment time.

Evaluation of the Cerebrospinal Fluid Flow Dynamics with Microvascular Imaging Ultrasound in Infants.

PURPOSE: Microvascular imaging ultrasound (MVI) can detect slow blood flow in small-caliber cerebral vessels. This technology may help assess flow in other intracranial structures, such as the ventricular system. In this study, we describe the use of MVI for characterizing intraventricular cerebrospinal fluid (CSF) flow dynamics in infants. MATERIALS AND METHODS: We included infants with brain ultrasound that had MVI B-Flow cine clips in the sagittal plane. Two blinded reviewers examined the images, dictated a diagnostic impression, and identified the third ventricle, cerebral aqueduct, fourth ventricle, and CSF flow direction. A third reviewer evaluated the discrepancies. We evaluated the association of visualization of CSF flow as detectable with MVI, with the diagnostic impressions. We also assessed the inter-rater reliability (IRR) for detecting CSF flow. RESULTS: We evaluated 101 infants, mean age 40 ± 53 days. Based on brain MVI B-Flow, a total of 49 patients had normal brain US scans, 40 had hydrocephalus, 26 had intraventricular hemorrhage (IVH), and 14 had hydrocephalus+IVH. Using spatially moving MVI signal in the third ventricle, cerebral aqueduct, and fourth ventricle as the criteria for CSF flow, CSF flow was identified in 10.9% (n = 11), 15.8% (n = 16), and 16.8% (n = 17) of cases, respectively. Flow direction was detected in 19.8% (n = 20) of cases; 70% (n = 14) was caudocranial, 15% (n = 3) was craniocaudal, and 15% (n = 3) bidirectional, with IRR = 0.662, p < 0.001. Visualization of CSF flow was significantly associated with the presence of IVH alone (OR 9.7 [3.3-29.0], p < 0.001) and IVH+hydrocephalus (OR 12.4 [3.5-440], p < 0.001), but not with hydrocephalus alone (p = 0.116). CONCLUSION: This study demonstrates that MVI can detect CSF flow dynamics in infants with a history of post-hemorrhagic hydrocephalus with a high IRR.

Ultrasound-Estimated Bladder Weight Correlates With Videourodynamic Studies in Neurogenic Bladder Dysfunction.

PURPOSE: This retrospective study was designed to evaluate which lower urinary tract ultrasound parameter(s) could predict the results of invasive urodynamic testing which are the current reference standard in the evaluation of bladder dysfunction in children with spina bifida. MATERIALS AND METHODS: Fifty eight children with spina bifida undergoing video urodynamic evaluation and a renal bladder ultrasound as their standard of care were evaluated. Quantitative and qualitative ultrasound parameters were then correlated with the videourodynamic study results which served as the reference standard. RESULTS: For bladders with ending storage pressures above 15 cm H2 O, there were increases in these ultrasound measured parameters: 1) bladder mass (P = .00019), 2) bladder/body mass ratio (P = .0059), and 3) wall thickness (P = .01). We defined the storage cost as the final storage pressure divided by the percentage of expected bladder capacity attained. These data were analyzed to compute receiver operating curves with assuming end storage pressures cutoff points of 15, 20, 30, and 40 cm H2 O. The optimal area under the curve was found for a bladder weight of 65 g and a pressure cutoff of 30 cm H2 O with a sensitivity of 75% with a specificity of 84%. CONCLUSION: Bladder weight is independent of luminal volume, can be normalized to body weight, and may serve as a clinically valuable tool for noninvasive screening to define a subset of patients with neurogenic bladder with a higher likelihood of having abnormal videourodynamic results.

A concise guide to transtemporal contrast-enhanced ultrasound in children.

Brain contrast-enhanced ultrasound offers insights into the brain beyond the anatomic information offered by conventional grayscale ultrasound. In infants, the open fontanelles serve as acoustic windows. In children, whose fontanelles are closed, the temporal bone serves as the ideal acoustic window due to its relatively smaller thickness than the other skull bones. Diagnosis of common neurologic diseases such as stroke, hemorrhage, and hydrocephalus has been performed using the technique. Transtemporal ultrasound and contrast-enhanced ultrasound, however, are rarely used in children due to the prevalent notion that the limited acoustic penetrance degrades diagnostic quality. This review seeks to provide guidelines for the use of transtemporal brain contrast-enhanced ultrasound in children.

Cerebral Blood Flow of the Neonatal Brain after Hypoxic-Ischemic Injury.

OBJECTIVE: Hypoxic-ischemic encephalopathy (HIE) in infants can have long-term adverse neurodevelopmental effects and markedly reduce quality of life. Both the initial hypoperfusion and the subsequent rapid reperfusion can cause deleterious effects in brain tissue. Cerebral blood flow (CBF) assessment in newborns with HIE can help detect abnormalities in brain perfusion to guide therapy and prognosticate patient outcomes. STUDY DESIGN: The review will provide an overview of the pathophysiological implications of CBF derangements in neonatal HIE, current and emerging techniques for CBF quantification, and the potential to utilize CBF as a physiologic target in managing neonates with acute HIE. CONCLUSION: The alterations of CBF in infants during hypoxia-ischemia have been studied by using different neuroimaging techniques, including nitrous oxide and xenon clearance, transcranial Doppler ultrasonography, contrast-enhanced ultrasound, arterial spin labeling MRI, 18F-FDG positron emission tomography, near-infrared spectroscopy (NIRS), functional NIRS, and diffuse correlation spectroscopy. Consensus is lacking regarding the clinical significance of CBF estimations detected by these different modalities. Heterogeneity in the imaging modality used, regional versus global estimations of CBF, time for the scan, and variables impacting brain perfusion and cohort clinical characteristics should be considered when translating the findings described in the literature to routine practice and implementation of therapeutic interventions. KEY POINTS: · Hypoxic-ischemic injury in infants can result in adverse long-term neurologic sequelae.. · Cerebral blood flow is a useful biomarker in neonatal hypoxic-ischemic injury.. · Imaging modality, variables affecting cerebral blood flow, and patient characteristics affect cerebral blood flow assessment..

Neonatal neurosonography practices: a survey of active Society for Pediatric Radiology members.

BACKGROUND: While neonatal brain US is emerging as an imaging modality with greater portability, widespread availability and relative lower cost compared to MRI, it is unknown whether US is being maximized in infants to increase sensitivity in detecting intracranial pathology related to common indications such as hemorrhage, ischemia and ventriculomegaly. OBJECTIVE: To survey active members of the Society for Pediatric Radiology (SPR) regarding their utilization of various cranial US techniques and reporting practices in neonates. MATERIALS AND METHODS: We distributed an online 10-question survey to SPR members to assess practice patterns of neonatal cranial US including protocol details, use of additional sonographic views, perceived utility of spectral Doppler evaluation, and germinal matrix hemorrhage and ventricular size reporting preferences. RESULTS: Of the 107 institutions represented, 90% of respondents were split evenly between free-standing children's hospitals and pediatric departments attached to a general hospital. We found that most used template reporting (72/107, 67%). The anterior fontanelle approach was standard practice (107/107, 100%). We found that posterior fontanelle views (72% sometimes, rarely or never) and high-frequency linear probes to evaluate far-field structures (52% sometimes, rarely or never) were seldom used. Results revealed a range of ways to report germinal matrix hemorrhage and measure ventricular indices to assess ventricular dilatation. There was substantial intra-institutional protocol and reporting variability as well. CONCLUSION: Our results demonstrate high variability in neurosonography practice and reporting among active SPR members, aside from the anterior fontanelle views, template reporting and linear high-resolution near-field evaluation. Standardization of reporting germinal matrix hemorrhage and ventricular size would help ensure a more consistent application of neonatal US in research and clinical practice.

Transtemporal brain contrast-enhanced ultrasound in children: preliminary experience in patients without neurological disorders.

AIM: To evaluate the use of transtemporal brain contrast-enhanced ultrasound (CEUS) to assess cerebral blood perfusion in a cohort of children without neurological disorders. METHODS: We included pediatric patients who were undergoing a clinically-indicated CEUS study. Brain scans were performed with a Siemens Sequoia scanner and a 4V1 transducer, that was placed on the left transtemporal bone. Brain scans were performed simultaneously with the images of the clinically-indicated organ of interest. Qualitative and quantitative analysis was performed to evaluate the hemispherical blood flow at the level of the midbrain during the wash-in and wash-out phases of the time-intensity curve. Clinical charts were reviewed to evaluate post-CEUS adverse events. RESULTS: Five patients were evaluated (mean age 5.8 ± 5.1 years). Qualitatively, more avid enhancement in the midbrain than the cortex was observed. Structures depicted ranged between the centrum semiovale at the level of the lateral ventricles and the midbrain. A quantitative analysis conducted on four patients demonstrated less avid perfusion on the contralateral (i.e. right) side, with a mean left/right ratio ranging between 1.51 and 4.07. In general, there was a steep positive wash-in slope starting at approximately 10 s after contrast injection, reaching a peak intensity around 15-26 s on the left side, and 17-29 s on the right side. No adverse events were reported. CONCLUSION: Transtemporal brain CEUS is feasible and safe in the pediatric population and allows qualitative and quantitative assessment of cerebral perfusion.

Sonothrombolysis: State-of-the-Art and Potential Applications in Children.

In recent years, advances in ultrasound therapeutics have been implemented into treatment algorithms for the adult population; however, the use of therapeutic ultrasound in the pediatric population still needs to be further elucidated. In order to better characterize the utilization and practicality of sonothrombolysis in the juvenile population, the authors conducted a literature review of current pediatric research in therapeutic ultrasound. The PubMed database was used to search for all clinical and preclinical studies detailing the use and applications of sonothrombolysis, with a focus on the pediatric population. As illustrated by various review articles, case studies, and original research, sonothrombolysis demonstrates efficacy and safety in clot dissolution in vitro and in animal studies, particularly when combined with microbubbles, with potential applications in conditions such as deep venous thrombosis, peripheral vascular disease, ischemic stroke, myocardial infarction, and pulmonary embolism. Although there is limited literature on the use of therapeutic ultrasound in children, mainly due to the lower prevalence of thrombotic events, sonothrombolysis shows potential as a noninvasive thrombolytic treatment. However, more pediatric sonothrombolysis research needs to be conducted to quantify the safety and ethical considerations specific to this vulnerable population.

Utility of Cerebral Microvascular Imaging in Infants Undergoing ECMO.

PURPOSE: Infants who require extracorporeal membrane oxygenation (ECMO) therapy have an increased risk of neurological complications and mortality. Microvascular imaging (MVI) is an advanced Doppler technique that allows high-resolution visualization of microvasculature in the brain. We describe the feasibility and utility of MVI for the evaluation of cerebral microvascular perfusion in patients undergoing ECMO. METHODS: We retrospectively analyzed brain MVI scans of neonates undergoing ECMO. Two pediatric radiologists qualitatively assessed MVI scans to determine the presence or absence of tortuosity, symmetry, heterogeneity, engorgement, and hypoperfusion of the basal ganglia-thalamus (BGT) region, as well as the presence or absence of white matter vascular engorgement and increased peri-gyral flow in the cortex. We tested the association between the presence of the aforementioned brain MVI features and clinical outcomes. RESULTS: We included 30 patients, 14 of which were male (46.7%). The time of ECMO duration was 11.8 ± 6.9 days. The most prevalent microvascular finding in BGT was lenticulostriate vessel tortuosity (26/30, 86.7%), and the most common microvascular finding in the cortex was increased peri-gyral flow (10/24, 41.7%). Cortical white matter vascular engorgement was significantly associated with the presence of any poor outcome as defined by death, seizure, and/or cerebrovascular events on magnetic resonance imaging (p = 0.03). CONCLUSION: MVI is a feasible modality to evaluate cerebral perfusion in infants undergoing ECMO. Additionally, evidence of white matter vascular engorgement after ECMO cannulation could serve as a predictor of poor outcomes in this population.

Quantitative Evaluation of Brain Echogenicity in Hypoxic-Ischemic Encephalopathy in Term Neonates Compared with Controls.

Purpose Neurosonography evaluation of neonatal hypoxic-ischemic encephalopathy (HIE) is mainly qualitative. We aimed to quantitatively compare the echogenicity of several brain regions in patients with HIE to healthy controls. Materials and Methods 20 term neonates with clinical/MRI evidence of HIE and 20 term healthy neonates were evaluated. Seven brain regions were assessed [frontal, parietal, occipital, and perirolandic white matter (WM), caudate nucleus head, lentiform nucleus, and thalamus]. The echogenicity of the calvarial bones (bone) and the choroid plexus (CP) was used for ratio calculation. Differences in the ratios were determined between neonates with HIE and controls. Results Ratios were significantly higher for HIE neonates in each region (p<0.05). The differences were greatest for the perirolandic WM, with CP and bone ratios being 0.23 and 0.22 greater, respectively, for the HIE compared to the healthy neonates (p<0.001). The perirolandic WM had a high AUC, at 0.980 for both the CP and bone ratios. The intra-observer reliability for all ratios was high, with the caudate to bone ratio being the lowest at 0.832 and the anterior WM to CP ratio being the highest at 0.992. Conclusion When coupled with internal controls, quantitative neurosonography represents a potential tool to identify early neonatal HIE changes. Larger cohort studies could reveal whether a quantitative approach can discern between degrees of severity of HIE. Future neurosonography protocols should be tailored to evaluate the perirolandic region, which requires posterior coronal scanning.