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Trong N. Nguyen Anthony S. Podkowa Trevor H. Park Rita J. Miller Minh N. Do Michael L. Oelze 《Ultrasound in medicine & biology》2021,47(3):556-568
Quantitative ultrasound (QUS) was used to classify rabbits that were induced to have liver disease by placing them on a fatty diet for a defined duration and/or periodically injecting them with CCl4. The ground truth of the liver state was based on lipid liver percents estimated via the Folch assay and hydroxyproline concentration to quantify fibrosis. Rabbits were scanned ultrasonically in vivo using a SonixOne scanner and an L9-4/38 linear array. Liver fat percentage was classified based on the ultrasonic backscattered radiofrequency (RF) signals from the livers using either QUS or a 1-D convolutional neural network (CNN). Use of QUS parameters with linear regression and canonical correlation analysis demonstrated that the QUS parameters could differentiate between livers with lipid levels above or below 5%. However, the QUS parameters were not sensitive to fibrosis. The CNN was implemented by analyzing raw RF ultrasound signals without using separate reference data. The CNN outputs the classification of liver as either above or below a threshold of 5% fat level in the liver. The CNN outperformed the classification utilizing the QUS parameters combined with a support vector machine in differentiating between low and high lipid liver levels (i.e., accuracies of 74% versus 59% on the testing data). Therefore, although the CNN did not provide a physical interpretation of the tissue properties (e.g., attenuation of the medium or scatterer properties) the CNN had much higher accuracy in predicting fatty liver state and did not require an external reference scan. 相似文献
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T.V. Nguyen G. Damiani L.A.V. Orenstein I. Hamzavi G.B. Jemec 《Journal of the European Academy of Dermatology and Venereology》2021,35(1):50-61
Hidradenitis suppurativa (HS) is a chronic inflammatory skin disease that severely impairs patients' quality of life. It is characterized by recurrent painful nodules, abscesses and draining sinus tracts in primarily intertriginous areas. We aimed to review the most up‐to‐date information regarding the epidemiology, clinical presentation, diagnostic studies, pathogenesis, comorbidities and quality of life of patients with hidradenitis suppurativa. We performed a systematic search of Medline, Embase database (from inception to September 2019) and review of bibliographies without restrictions on year or language. HS has an estimated global prevalence of 0.00033–4.1% (but most likely 0.7–1.2% in the European‐US population). Patients still experience a significant diagnostic delay, up to several years. In the absence of pathognomonic tests, the diagnosis of HS is made from clinical observation and the disease narrative. Phenotypic variation renders diagnosis and severity assessment difficult. Ultrasound imaging is an emerging assessment tool for deep‐seated lesions. The Hurley Staging System is still widely used in severity rating. Follicular hyperkeratosis and dilatation, follicular rupture and chronic inflammation with architectural tissue changes have been implicated in the pathogenesis of HS. HS has been associated with metabolic syndrome and other risk factors for cardiovascular disease, diabetes mellitus type II, polycystic ovarian syndrome, depression, suicide and substance use disorders. It has been linked to other immune‐mediated diseases such as inflammatory bowel disease and spondyloarthropathy. Pain, pruritus, malodour, low self‐esteem, sleep and sexual dysfunctions, and poor mental health are chronic symptoms or consequences of uncontrolled disease. HS is an under‐diagnosed and under‐treated disease with a profound negative impact on patients' quality of life. In the light of its associated comorbidities, an interdisciplinary management approach may be needed to ensure the best outcomes. 相似文献
35.
Frietsch T. Steinbicker A. U. Hackbusch M. Nguyen X. D. Dietrich G. 《Der Anaesthesist》2020,69(5):331-351
Die Anaesthesiologie - Fremdbluttransfusionen sind bei vielen onkologischen Eingriffen durch die Anwendung der maschinellen Autotransfusion (MAT) vermeidbar. Es ist fraglich, ob mit dem Einsatz von... 相似文献
36.
Yan Xiang Ata S. Moshiri Edward F. Chan Trisha S. Dasgupta Heidi Kozic Rosalie Elenitsas Cuong V. Nguyen 《Journal of cutaneous pathology》2020,47(3):286-290
Sclerotic lipomas, a lipoma variant, are benign subcutaneous tumors, so-named because of their resemblance to sclerotic fibromas. Previous literature has suggested that these tumors may show a predilection for middle-aged adult males. We report an unusual case of a sclerotic lipoma diagnosed on the scalp of a 66-year-old female. The patient presented to the outpatient clinic with a 3- to 4-year history of an enlarging and irritated 2.6-cm nodule on the anterior crown of the scalp, clinically thought to be a pilar cyst. Histopathological examination from the excisional specimen revealed a well-circumscribed dermal to subcutaneous tumor with ample sclerotic collagen bundles, an increased number of CD34 positive spindled cells, and prominent S-100 positive mature adipocytes comprising greater than 50% of the tumor. We present this case given its atypical clinical and histopathological presentation, review the literature of sclerotic lipomas, and discuss the differential diagnosis to raise awareness of this rare entity. 相似文献
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Anita Nguyen Hartzell V. Schaff Dustin Hang Rick A. Nishimura Jeffrey B. Geske Joseph A. Dearani Brian D. Lahr Steve R. Ommen 《The Journal of thoracic and cardiovascular surgery》2019,157(1):306-315.e3
Objectives
In patients with hypertrophic cardiomyopathy, obstruction of the left ventricular outflow tract can be relieved by surgical septal myectomy or alcohol septal ablation, but uncertainty remains regarding long-term results and comparative effectiveness of alcohol septal ablation. This study aims to compare short- and long-term outcomes of the 2 procedures.Methods
Between December 1998 and September 2016, 2407 patients underwent septal myectomy and 211 patients underwent alcohol septal ablation at our institution. After 2:1 propensity score matching, the study cohort included 334 patients who underwent myectomy and 167 patients who underwent alcohol septal ablation.Results
Median (interquartile range) ages of patients in the myectomy and alcohol septal ablation groups were 65 (58-71) years and 64 (56-73) years (P = .9), respectively. After intervention, median resting left ventricular outflow tract gradient at predischarge transthoracic echocardiography was 0 (0-10) mm Hg in the myectomy group (n = 288) and 21 (10-60) mm Hg in the alcohol septal ablation group (n = 63) (P < .001, tested at baseline gradients of 30 and 50 mm Hg). There were no differences in survival between the 2 groups (risk of death for alcohol septal ablation vs myectomy, hazard ratio, 1.5; 95% confidence interval, 0.9-2.6; P = .1). Survival of patients undergoing septal myectomy was better than that of an age-, sex-, and race-matched US population (82% vs 75% at 12 years, P = .01). Reintervention for left ventricular outflow tract obstruction was more likely to occur in patients who received alcohol septal ablation (hazard ratio, 33.3; 95% confidence interval, 4.4-250.6; P < .001).Conclusions
There were no differences in survival of patients undergoing myectomy or alcohol septal ablation, but freedom from reintervention and early and late reduction of left ventricular outflow tract gradient are superior in patients undergoing septal myectomy. 相似文献40.