Quantitative ultrasound fatty liver evaluation in a pediatric population: comparison with magnetic resonance imaging of liver proton density fat fraction.

BACKGROUND: Biopsy remains the gold standard for the diagnosis of hepatic steatosis, the leading cause of pediatric chronic liver disease; however, its costs call for less invasive methods. OBJECTIVE: This study examined the diagnostic accuracy and reliability of quantitative ultrasound (QUS) for the assessment of liver fat content in a pediatric population, using magnetic resonance imaging proton density fat fraction (MRI-PDFF) as the reference standard. MATERIALS AND METHODS: We enrolled 36 patients. MRI-PDFF involved a 3-dimensional T2*-weighted with Dixon pulse multiple-echo sequence using iterative decomposition of water and fat with echo asymmetry and least squares estimation (IDEAL IQ). QUS imaging relied on the ultrasound system "RS85 A" (Samsung Medison, Seoul, South Korea) and the following software: Hepato-Renal Index with automated region of interest recommendation (EzHRI), Tissue Attenuation Imaging (TAI), and Tissue Scatter Distribution Imaging (TSI). For each QUS index, receiver operating characteristic (ROC) curve analysis against MRI-PDFF was used to identify the associated cut-off value and the area under the ROC curve (AUROC). Concordance between two radiologists was assessed by intraclass correlation coefficients (ICCs) and Bland-Altman analysis. RESULTS: A total of 61.1% of the sample (n=22) displayed a MRI-PDFF ≥ 5.6%; QUS cut-off values were TAI=0.625 (AUROC 0.90, confidence interval [CI] 0.77-1.00), TSI=91.95 (AUROC 0.99, CI 0.98-1.00) and EzHRI=1.215 (AUROC 0.98, CI 0.94-1.00). Inter-rater reliability was good-to-excellent for EzHRI (ICC 0.91, 95% C.I. 0.82-0.95) and TAI (ICC 0.94, 95% C.I. 0.88-0.97) and moderate to good for TSI (ICC 0.73; 95% C.I. 0.53-0.85). CONCLUSION: Our results suggest that QUS can be used to reliably assess the presence and degree of pediatric hepatic steatosis.

Neurophysiological patterns of acute and post-acute foodborne botulism.

INTRODUCTION/AIMS: Neurophysiological patterns in patients with foodborne botulism are rarely described after the acute phase. We report data from a large Italian outbreak of botulism, with patients evaluated at different timepoints after poisoning. METHODS: Eighteen male patients (mean age 47 ± 8.4 y) underwent 22 clinical and neurophysiological evaluations (4 patients were re-evaluated). The resting compound muscle action potential (CMAP) amplitude, postexercise CMAP amplitude, CMAP change after high-frequency (50 Hz) repetitive nerve stimulation (HFRNS), and motor unit action potentials (MUAPs) were assessed in the acute (4-8 days after poisoning; 5 patients), early post-acute (32-39 days after poisoning; 5 patients), and late post-acute (66-80 days after poisoning; 12 patients) phases. RESULTS: In the acute, early post-acute, and late post-acute phases, respectively, reduced CMAP amplitudes were found in 100%, 20%, and 17% of patients; abnormal postexercise CMAP facilitation was observed in 100%, 40%, and 0% of patients; and pathological incremental responses to HFRNS were found in 80%, 50%, and 8% of patients. Baseline CMAP amplitudes, postexercise CMAP facilitation, and CMAP increases in response to HFRNS differed significantly between the acute and post-acute phases. Small MUAPs were found in 100% of patients in the acute and early post-acute phases and in 50% of patients in the late post-acute phase. DISCUSSION: The neurophysiological findings of foodborne botulism vary considerably according to the evaluation time point. In the post-acute phase, different neurophysiological techniques must be applied to support a diagnosis of botulism.

Unusual application of twinkling artifact.

INTRODUCTION: The aim of this paper is to show how to improve diagnostic accuracy using CDUS and twinkling artifact in patients experiencing discomfort due to the presence of small FBs in the soft tissues not clearly visible at US grayscale examination. MATERIALS AND METHODS: We enrolled 7 adult patients presenting with small (2-4 mm) superficial FBs located in the subcutaneous and muscle tissues, barely or not detectable on US grayscale. All patients underwent US grayscale and CDUS examinations. RESULTS: We identified superficial FB with twinkling artifact in all 7 patients. All of these were confirmed to represent foreign bodies after surgical excision. CONCLUSION: TA is useful in the evaluation of subcutaneous and muscular FBs and provides information on their location, depth and shape, which is useful if surgical excision is required.

Imaging of Carotid Stenosis: Where Are We Standing? Comparison of Multiparametric Ultrasound, CT Angiography, and MRI Angiography, with Recent Developments.

Atherosclerotic disease of the carotid arteries is a crucial risk factor in predicting the likelihood of future stroke events. In addition, emerging studies suggest that carotid stenosis may also be an indicator of plaque load on coronary arteries and thus have a correlation with the risk of acute cardiovascular events. Furthermore, although in symptomatic patients the degree of stenosis is the main morphological parameter studied, recent evidence suggests, especially in asymptomatic patients, that plaque vulnerability should also be evaluated as an emerging and significant imaging parameter. The reference diagnostic methods for the evaluation of carotid stenosis are currently ultrasonography, magnetic resonance imaging (MRI), and computed tomography angiography (CTA). In addition, other more invasive methods such as 123I-metaiodobenzylguanidine (MIBG) scintigraphy and PET-CT, as well as digital subtraction angiography, can be used. Each method has advantages and disadvantages, and there is often some confusion in their use. For example, the usefulness of MRI is often underestimated. In addition, implementations for each method have been developed over the years and are already enabling a significant increase in diagnostic accuracy. The purpose of our study is to make an in-depth analysis of all the methods in use and in particular their role in the diagnostic procedure of carotid stenosis, also discussing new technologies.

Postprandial hypotension as a predictor of respiratory failure in patients with foodborne botulinum intoxication - a case-control study in outbreak investigation.

OBJECTIVES: Botulism is a rare syndrome characterized by acute, flaccid paralysis with possible involvement of respiratory muscle-producing pump failure requiring mechanical ventilation. A predominance of autonomic involvement can occur. METHODS: We enrolled patients affected by foodborne botulism during an outbreak. All patients underwent the detection of the toxin in stool specimens, and 24-hour ambulatory blood pressure monitoring (ABPM). A blinded expert operator analyzed ABPM data for the diagnosis of hypertension and postprandial hypotension (PPH). RESULTS: Twenty male patients met the inclusion and exclusion criteria. Thirty-four healthy subjects matched for sex and age were enrolled as a control group. PPH was significantly more frequent in the botulin group than in healthy subjects (40% vs 2.9%, P <0.0001). At the logistic regression, the probability that patients affected by botulinum could require ventilation was increased by 733% (adjusted odds ratio: 8.33) when PPH is encountered. CONCLUSIONS: The likelihood of resorting to ventilation in subjects with botulinum intoxication was seven times greater in patients presenting PPH. These results could allow the prompt identification of patients at high risk for requiring ventilation.

New Technologies in the Assessment of Carotid Stenosis: Beyond the Color-Doppler Ultrasound-High Frame Rate Vector-Flow and 3D Arterial Analysis Ultrasound.

Atherosclerotic plaque in the carotid artery is the main cause of ischemic stroke, with a high incidence rate among people over 65 years. A timely and precise diagnosis can help to prevent the ischemic event and decide patient management, such as follow up, medical, or surgical treatment. Presently, diagnostic imaging techniques available include color-Doppler ultrasound, as a first evaluation technique, computed tomography angiography, which, however, uses ionizing radiation, magnetic resonance angiography, still not in widespread use, and cerebral angiography, which is an invasively procedure reserved for therapeutically purposes. Contrast-enhanced ultrasound is carving out an important and emerging role which can significantly improve the diagnostic accuracy of an ultrasound. Modern ultrasound technologies, still not universally utilized, are opening new horizons in the arterial pathologies research field. In this paper, the technical development of various carotid artery stenosis diagnostic imaging modalities and their impact on clinical efficacy is thoroughly reviewed.