Cortico-Cortical Evoked Potentials: Automated Localization and Classification of Early and Late Responses.

Background: Cortico-cortical evoked potentials (CCEPs), elicited via single-pulse electrical stimulation, are used to map brain networks. These responses comprise early (N1) and late (N2) components, which reflect direct and indirect cortical connectivity. Reliable identification of these components remains difficult due to substantial variability in amplitude, phase, and timing.

Artifacts in photoacoustic imaging: Origins and mitigations.

Photoacoustic imaging (PAI) is rapidly moving from the laboratory to the clinic, increasing the need to understand confounders which might adversely affect patient care. Over the past five years, landmark studies have shown the clinical utility of PAI, leading to regulatory approval of several devices. In this article, we describe the various causes of artifacts in PAI, providing schematic overviews and practical examples, simulated as well as experimental.

Three-Dimensional Whole-Body Small Animal Photoacoustic Tomography Using a Multi-View Fabry-Perot Scanner.

Photoacoustic tomography (PAT) has the potential to become a widely used imaging tool in preclinical studies of small animals. This is because it can provide non-invasive, label free images of whole-body mouse anatomy, in a manner which is challenging for more established imaging modalities. However, existing PAT scanners are limited because they either do not implement a full 3-D tomographic reconstruction using all the recorded photoacoustic (PA) data and/or do not record the available 3-D PA time-series data around the mouse with sufficiently high spatial resolution ( m), which compromises image quality in terms of resolution, imaging depth and the introduction of artefacts.

Accuracy of SEEG Source Localization: A Pilot Study Using Corticocortical Evoked Potentials.

Introduction: EEG source localization is an established technique for localizing scalp EEG in medically refractory epilepsy but has not been adequately studied with intracranial EEG (iEEG). Differences in sensor location and spatial sampling may affect the accuracy of EEG source localization with iEEG. Corticocortical evoked potentials can be used to evaluate EEG source localization algorithms for iEEG given the known source location.

Seizure outcomes after resection of temporal encephalocele in patients with drug-resistant epilepsy: A systematic review and meta-analysis.

Objective: Temporal encephaloceles (TEs) are seen in patients with drug-resistant epilepsy (DRE); yet they are also common incidental findings. Variability in institutional pre-surgical epilepsy practices and interpretation of epileptogenic network localization contributes to bias in existing epilepsy cohorts with TE, and therefore the relevance of TE in DRE remains controversial. We sought to estimate effect sizes and sample sizes necessary to demonstrate clinically relevant improvements in seizure outcome with different surgical approaches.

Multi-Modal Investigation of Metabolism in Murine Breast Cancer Cell Lines Using Fluorescence Lifetime Microscopy and Hyperpolarized 13C-Pyruvate Magnetic Resonance Spectroscopy.

: Despite the role of metabolism in breast cancer metastasis, we still cannot predict which breast tumors will progress to distal metastatic lesions or remain dormant. This work uses metabolic imaging to study breast cancer cell lines (4T1, 4T07, and 67NR) with differing metastatic potential in a 3D collagen gel bioreactor system. : Within the bioreactor, hyperpolarized magnetic resonance spectroscopy (HP-MRS) is used to image lactate/pyruvate ratios, while fluorescence lifetime imaging microscopy (FLIM) of endogenous metabolites measures metabolism at the cellular scale.

The clinical spectrum of MELAS and associated disorders across ages: a retrospective cohort study.

Objective: Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) is a severe multisystemic disease, although some have a milder phenotype. We aimed to evaluate the clinical spectrum of this disease from MELAS patients to asymptomatic carriers and identify predictors of severity.

Methods: We reviewed 81 patients, who had MELAS or had positive genetics without meeting clinical criteria.

EEG Source Localization in Temporal Encephaloceles: Concordance With Surgical Resection and Clinical Outcomes.

Purpose: Temporal encephaloceles are a cause of drug-resistant temporal lobe epilepsy; however, their relationship with epileptogenesis is unclear, and optimal surgical resection is uncertain. EEG source localization (ESL) may guide surgical decision-making.

Methods: We reviewed patients at Mayo Clinic Rochester with drug-resistant temporal lobe epilepsy and temporal encephaloceles, who underwent limited resection and had 1-year outcomes.

Understanding lower limb blood flow occlusion parameters for use in field-based settings.

Reduction of blood flow to the limb using cuffs before or during exercise has become increasingly popular for training and rehabilitation. Our study tested the effects of cuff brand/width on pressures required to reach limb occlusion pressure (LOP) and developed, cross-validated, and compared accuracy of two LOP prediction equations to previously created methods. Supine LOP was determined in the distal popliteal artery using four different cuff brands/widths in 23 adult participants.

Stereo-EEG localization of midline onset seizures on scalp EEG.

Purpose: The objective of this study was to describe the sEEG-defined seizure onset zone (SOZ), seizure semiology, presurgical evaluations, surgical intervention and outcome in patients with midline onset noninvasive phase I monitoring.

Methods: A single center sEEG database was reviewed to identify patients with seizures onset predominantly involving midline electrodes (FZ, CZ, PZ, OZ) on scalp EEG. Data abstracted included clinical factors, seizure semiology graded into lobar segmentation, imaging and electrographic findings, sEEG plan, interventions, and outcome.

Percutaneous Achilles Tendon Repair Using Ultrasound Guidance: An Intraoperative Ultrasound Technique.

Rupture of the Achilles tendon is a common injury seen in patients of varying ages and activity levels. There are many considerations for treatment of these injuries, with both operative and nonoperative management providing satisfactory outcomes in the literature. The decision to proceed with surgical intervention should be individualized for each patient, including the patient's age, future athletic goals, and comorbidities.

Non-alcoholic fatty liver disease (NAFLD) in Filipino North American patients: Results from a multi-ethnic cohort.

Background: Non-alcoholic fatty liver disease (NAFLD) is more prevalent in certain ethnicities due to a combination of genetic, environmental, and metabolic factors. North American Filipino populations may have lifestyle and metabolic risk factors for NAFLD; however, the prevalence of NAFLD in this group is unknown. We sought to determine whether Filipino patients are over-represented in a multi-ethnic NAFLD cohort and describe their clinical presentation, primarily compared to other ethnicities in the same geographical region and secondarily compared to Manila-based Filipino patients.

Subclinical seizures on stereotactic EEG: characteristics and prognostic value.

Objective: Although stereotactic EEG (sEEG) has become a widely used intracranial EEG technique, the significance of subclinical seizures (SCS) recorded on sEEG is unclear and studies examining this finding on sEEG are limited. We investigated (1) the prevalence of SCS in patients undergoing sEEG and clinical factors associated with their presence, (2) how often the subclinical seizure onset zone (SOZ) colocalizes with clinical SOZ, (3) the association of SCS and surgical outcomes, and (4) the influence of resection of the subclinical SOZ on surgical outcome.

Methods: We reviewed all patients who underwent intracranial monitoring with sEEG at our institution from 2015 through 2020 (n=169).

Validation of Monte Carlo I radiopharmaceutical dosimetry workflow using a 3D-printed anthropomorphic head and neck phantom.

Purpose: Approximately 50% of head and neck cancer (HNC) patients will experience loco-regional disease recurrence following initial courses of therapy. Retreatment with external beam radiotherapy (EBRT) is technically challenging and may be associated with a significant risk of irreversible damage to normal tissues. Radiopharmaceutical therapy (RPT) is a potential method to treat recurrent HNC in conjunction with EBRT.

Adolescent Baseball Pitchers With Ulnar Collateral Ligament Tears Exhibit a High Proportion of Partial Tears.

Background: Ulnar collateral ligament (UCL) tears in the throwing elbow are classified according to grade and location using magnetic resonance arthrography (MRA). However, the frequency of each tear type and the association to age, competition level, and radiographic findings in adolescent baseball pitchers are unknown.

Purposes: The primary purpose of this study was to use MRA to characterize the severity, location, and UCL tear type in adolescent pitchers.

EEG source imaging concordance with intracranial EEG and epileptologist review in focal epilepsy.

EEG source imaging is becoming widely used for the evaluation of medically refractory focal epilepsy. The validity of EEG source imaging has been established in several studies comparing source imaging to the surgical resection cavity and subsequent seizure freedom. We present a cohort of 87 patients and compare EEG source imaging of both ictal and interictal scalp EEG to the seizure onset zone on intracranial EEG.

A United States Fair Lending Perspective on Machine Learning.

The use of machine learning (ML) has become more widespread in many areas of consumer financial services, including credit underwriting and pricing of loans. ML's ability to automatically learn nonlinearities and interactions in training data is perceived to facilitate faster and more accurate credit decisions, and ML is now a viable challenger to traditional credit modeling methodologies. In this mini review, we further the discussion of ML in consumer finance by proposing uniform definitions of key ML and legal concepts related to discrimination and interpretability.

Hyperpolarized C Magnetic Resonance Spectroscopic Imaging of Pyruvate Metabolism in Murine Breast Cancer Models of Different Metastatic Potential.

This study uses dynamic hyperpolarized [1-C]pyruvate magnetic resonance spectroscopic imaging (MRSI) to estimate differences in glycolytic metabolism between highly metastatic (4T1, = 7) and metastatically dormant (4T07, = 7) murine breast cancer models. The apparent conversion rate of pyruvate-to-lactate (k) and lactate-to-pyruvate area-under-the-curve ratio (AUC) were estimated from the metabolite images and compared with biochemical metabolic measures and immunohistochemistry (IHC). A non-significant trend of increasing k ( = 0.

A device for the controlled cooling and freezing of excised plant specimens during magnetic resonance imaging.

Background: Investigating plant mechanisms to tolerate freezing temperatures is critical to developing crops with superior cold hardiness. However, the lack of imaging methods that allow the visualization of freezing events in complex plant tissues remains a key limitation. Magnetic resonance imaging (MRI) has been successfully used to study many different plant models, including the study of in vivo changes during freezing.

Measurement of the temperature-dependent output of lead zirconate titanate transducers.

The effect of temperature and electrical drive conditions on the output of lead zirconate titanate (PZT) transducers is of particular interest in ultrasound metrology and medical ultrasound applications. In this work, the temperature-dependent output of two single-element PZT transducers was measured between 22 °C and 46 °C. Two independent measurement methods were used, namely radiation force balance measurements and laser vibrometry.

Evaluating the effectiveness of a lower extremity venous phantom on developing ultrasound examination skills and confidence.

Introduction: The aims of this study were: (1) Determine the effect on student ultrasound scanning skills using a lower extremity venous ultrasound phantom in addition to standard teaching methods of didactic lecture and scanning live volunteers and (2) Determine the effect of using a lower extremity venous ultrasound phantom in addition to standard teaching methods of didactic lecture and scanning live volunteers on student confidence levels in performing the lower extremity venous ultrasound examination.

Methods: Participants were first year diagnostic medical sonography students with minimal scanning experience ( = 11), which were randomized into two groups. Group 1 ( = 5) received the standard didactic lecture and attended a scan lab assessment where they performed a lower extremity venous examination on a human volunteer.