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1.
Radiology ; 310(2): e232044, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38319166

RESUMEN

Background CT-guided high-dose-rate (HDR) brachytherapy (hereafter, HDR brachytherapy) has been shown to be safe and effective for patients with unresectable hepatocellular carcinoma (HCC), but studies comparing this therapy with other local-regional therapies are scarce. Purpose To compare patient outcomes of HDR brachytherapy and transarterial chemoembolization (TACE) in patients with unresectable HCC. Materials and Methods This multi-institutional retrospective study included consecutive treatment-naive adult patients with unresectable HCC who underwent either HDR brachytherapy or TACE between January 2010 and December 2022. Overall survival (OS) and progression-free survival (PFS) were compared between patients matched for clinical and tumor characteristics by propensity score matching. Not all patients who underwent TACE had PFS available; thus, a different set of patients was used for PFS and OS analysis for this treatment. Hazard ratios (HRs) were calculated from Kaplan-Meier survival curves. Results After propensity matching, 150 patients who underwent HDR brachytherapy (median age, 71 years [IQR, 63-77 years]; 117 males) and 150 patients who underwent TACE (OS analysis median age, 70 years [IQR, 63-77 years]; 119 male; PFS analysis median age, 68 years [IQR: 63-76 years]; 119 male) were analyzed. Hazard of death was higher in the TACE versus HDR brachytherapy group (HR, 4.04; P < .001). Median estimated PFS was 32.8 months (95% CI: 12.5, 58.7) in the HDR brachytherapy group and 11.6 months (95% CI: 4.9, 22.7) in the TACE group. Hazard of disease progression was higher in the TACE versus HDR brachytherapy group (HR, 2.23; P < .001). Conclusion In selected treatment-naive patients with unresectable HCC, treatment with CT-guided HDR brachytherapy led to improved OS and PFS compared with TACE. © RSNA, 2024 Supplemental material is available for this article. See also the editorial by Chapiro in this issue.


Asunto(s)
Braquiterapia , Carcinoma Hepatocelular , Quimioembolización Terapéutica , Neoplasias Hepáticas , Adulto , Anciano , Humanos , Masculino , Carcinoma Hepatocelular/diagnóstico por imagen , Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/terapia , Estudios Retrospectivos , Tomografía Computarizada por Rayos X
2.
Radiology ; 310(2): e231956, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-38376407

RESUMEN

Background Coronary CT angiography is a first-line test in coronary artery disease but is limited by severe calcifications. Photon-counting-detector (PCD) CT improves spatial resolution. Purpose To investigate the effect of improved spatial resolution on coronary stenosis assessment and reclassification. Materials and Methods Coronary stenoses were evaluated prospectively in a vessel phantom (in vitro) containing two stenoses (25%, 50%), and retrospectively in patients (in vivo) who underwent ultrahigh-spatial-resolution cardiac PCD CT (from July 2022 to April 2023). Images were reconstructed at standard resolution (section thickness, 0.6 mm; increment, 0.4 mm; Bv44 kernel), high spatial resolution (section thickness, 0.4 mm; increment, 0.2 mm; Bv44 kernel), and ultrahigh spatial resolution (section thickness, 0.2; increment, 0.1 mm; Bv64 kernel). Percentages of diameter stenosis (DS) were compared between reconstructions. In vitro values were compared with the manufacturer specifications of the phantom and patient results were assessed regarding effects on Coronary Artery Disease Reporting and Data System (CAD-RADS) reclassification. Results The in vivo sample included 114 patients (mean age, 68 years ± 9 [SD]; 71 male patients). In vitro percentage DS measurements were more accurate with increasing spatial resolution for both 25% and 50% stenoses (mean bias for standard resolution, high spatial resolution, and ultrahigh spatial resolution, respectively: 10.1%, 8.0%, and 2.3%; P < .001). In vivo results confirmed decreasing median percentage DS with increasing spatial resolution for calcified stenoses (n = 161) (standard resolution, high spatial resolution, and ultrahigh spatial resolution, respectively: 41.5% [IQR, 27.3%-58.2%], 34.8% [IQR, 23.7%-55.1%], and 26.7% [IQR, 18.6%-44.3%]; P < .001), whereas noncalcified (n = 13) and mixed plaques (n = 19) did not show evidence of a difference (P ≥ .88). Ultrahigh-spatial-resolution reconstructions led to reclassification of 62 of 114 (54.4%) patients to lower CAD-RADS category than that assigned using standard resolution. Conclusion In vivo and in vitro coronary stenosis assessment improved for calcified stenoses by using ultrahigh-spatial-resolution PCD CT reconstructions, leading to lower percentage DS compared with standard resolution and clinically relevant rates of reclassification. © RSNA, 2024 Supplemental material is available for this article. See also the editorial by McCollough in this issue.


Asunto(s)
Enfermedad de la Arteria Coronaria , Estenosis Coronaria , Humanos , Masculino , Anciano , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Constricción Patológica , Angiografía por Tomografía Computarizada , Estudios Retrospectivos , Estenosis Coronaria/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Angiografía Coronaria
3.
Small ; 20(10): e2305467, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37875633

RESUMEN

Clean water is one of the most important resources of the planet but human-made contamination with diverse pollutants increases continuously. Microplastics (<5 mm diameter) which can have severe impacts on the environment, are present worldwide. Degradation processes lead to nanoplastics (<1 µm), which are potentially even more dangerous due to their increased bioavailability. State-of-the-art wastewater treatment plants show a deficit in effectively eliminating micro- and nanoplastics (MNP) from water, particularly in the case of nanoplastics. In this work, the magnetic removal of three different MNP types across three orders of magnitude in size (100 nm-100 µm) is investigated systematically. Superparamagnetic iron oxide nanoparticles (SPIONs) tend to attract oppositely charged MNPs and form aggregates that can be easily collected by a magnet. It shows that especially the smallest fractions (100-300 nm) can be separated in ordinary high numbers (1013  mg-1 SPION) while the highest mass is removed for MNP between 2.5 and 5 µm. The universal trend for all three types of MNP can be fitted with a derived model, which can make predictions for optimizing SPIONs for specific size ranges in the future.

4.
BMC Med Educ ; 24(1): 619, 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38840140

RESUMEN

INTRODUCTION/AIM: Radiological imaging is crucial in modern clinical practice and requires thorough and early training. An understanding of cross-sectional imaging is essential for effective interpretation of such imaging. This study examines the extent to which completing an undergraduate ultrasound course has positive effects on the development of visual-spatial ability, knowledge of anatomical spatial relationships, understanding of radiological cross-sectional images, and theoretical ultrasound competencies. MATERIAL AND METHODS: This prospective observational study was conducted at a medical school with 3rd year medical students as part of a voluntary extracurricular ultrasound course. The participants completed evaluations (7-level Likert response formats and dichotomous questions "yes/no") and theoretical tests at two time points (T1 = pre course; T2 = post course) to measure their subjective and objective cross-sectional imaging skills competencies. A questionnaire on baseline values and previous experience identified potential influencing factors. RESULTS: A total of 141 participants were included in the study. Most participants had no previous general knowledge of ultrasound diagnostics (83%), had not yet performed a practical ultrasound examination (87%), and had not attended any courses on sonography (95%). Significant subjective and objective improvements in competencies were observed after the course, particularly in the subjective sub-area of "knowledge of anatomical spatial relationships" (p = 0.009). Similarly, participants showed improvements in the objective sub-areas of "theoretical ultrasound competencies" (p < 0.001), "radiological cross-section understanding and knowledge of anatomical spatial relationships in the abdomen" (p < 0.001), "visual-spatial ability in radiological cross-section images" (p < 0.001), and "visual-spatial ability" (p = 0.020). CONCLUSION: Ultrasound training courses can enhance the development of visual-spatial ability, knowledge of anatomical spatial relationships, radiological cross-sectional image understanding, and theoretical ultrasound competencies. Due to the reciprocal positive effects of the training, students should receive radiology training at an early stage of their studies to benefit as early as possible from the improved skills, particularly in the disciplines of anatomy and radiology.


Asunto(s)
Competencia Clínica , Educación de Pregrado en Medicina , Estudiantes de Medicina , Ultrasonografía , Humanos , Estudios Prospectivos , Masculino , Femenino , Evaluación Educacional , Adulto Joven , Adulto , Curriculum
5.
Laryngorhinootologie ; 2024 Jun 03.
Artículo en Alemán | MEDLINE | ID: mdl-38830381

RESUMEN

OBJECTIVE: Upper airway obstructions are usually acute emergencies. Coniotomy is the last option to secure the airway and can be supported by sonography. The aim of this study was to establish a training program to teach these skills. MATERIAL AND METHODS: The training consisted of theoretical training with an additional video presentation (10 minutes each) and practical training (45 minutes). Evaluations were completed before (T1) and after (T2) the training to measure prior experience and satisfaction with the training as well as subjective and objective competence levels. At T2, a practical test was also completed by n=113 participants. A standardized evaluation form was used to document the results of the practical test. RESULTS: A large proportion of the participants had neither seen a coniotomy (64.6%) nor performed one independently (79.6%). Significant improvement (T1 to T2) was measured with regard to the subjective assessment of competence (p<0.001). The training received positive ratings for all items tested (scale ranges 1-2). During practical tests, the participants achieved an average of 89.2% of the possible points and needed a mean of 101 ±23 seconds to identify the conic ligament. CONCLUSION: Structured training for sonographic identification of the conic ligament leads to significant improvement in the subjective assessment of competence and a high objective competence level in a short period of time. This type of training should be standardized in head and neck ultrasound training in the future.

6.
Eur Radiol ; 33(2): 1031-1039, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35986768

RESUMEN

OBJECTIVES: Low bone mineral density (BMD) was recently identified as a novel risk factor for patients with hepatocellular carcinoma (HCC). In this multicenter study, we aimed to validate the role of BMD as a prognostic factor for patients with HCC undergoing transarterial chemoembolization (TACE). METHODS: This retrospective multicenter trial included 908 treatment-naïve patients with HCC who were undergoing TACE as a first-line treatment, at six tertiary care centers, between 2010 and 2020. BMD was assessed by measuring the mean Hounsfield units (HUs) in the midvertebral core of the 11th thoracic vertebra, on contrast-enhanced computer tomography performed before treatment. We assessed the influence of BMD on median overall survival (OS) and performed multivariate analysis including established estimates for survival. RESULTS: The median BMD was 145 HU (IQR, 115-175 HU). Patients with a high BMD (≥ 114 HU) had a median OS of 22.2 months, while patients with a low BMD (< 114 HU) had a lower median OS of only 16.2 months (p < .001). Besides albumin, bilirubin, tumor number, and tumor diameter, BMD remained an independent prognostic factor in multivariate analysis. CONCLUSIONS: BMD is an independent predictive factor for survival in elderly patients with HCC undergoing TACE. The integration of BMD into novel scoring systems could potentially improve survival prediction and clinical decision-making. KEY POINTS: • Bone mineral density can be easily assessed in routinely acquired pre-interventional computed tomography scans. • Bone mineral density is an independent predictive factor for survival in elderly patients with HCC undergoing TACE. • Thus, bone mineral density is a novel imaging biomarker for prognosis prediction in elderly patients with HCC undergoing TACE.


Asunto(s)
Enfermedades Óseas Metabólicas , Carcinoma Hepatocelular , Quimioembolización Terapéutica , Neoplasias Hepáticas , Humanos , Anciano , Carcinoma Hepatocelular/diagnóstico por imagen , Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/terapia , Pronóstico , Quimioembolización Terapéutica/métodos , Estudios Retrospectivos , Resultado del Tratamiento
7.
J Cardiovasc Magn Reson ; 25(1): 33, 2023 06 19.
Artículo en Inglés | MEDLINE | ID: mdl-37331991

RESUMEN

BACKGROUND: MRI T2 mapping has been proven to be sensitive to the level of blood oxygenation. We hypothesized that impaired exercise capacity in chronic heart failure is associated with a greater difference between right (RV) to left ventricular (LV) blood pool T2 relaxation times due to a higher level of peripheral blood desaturation, compared to patients with preserved exercise capacity and to healthy controls. METHODS: Patients with chronic heart failure (n = 70) who had undergone both cardiac MRI (CMR) and a 6-min walk test (6MWT) were retrospectively identified. Propensity score matched healthy individuals (n = 35) served as control group. CMR analyses included cine acquisitions and T2 mapping to obtain blood pool T2 relaxation times of the RV and LV. Following common practice, age- and gender-adjusted nominal distances and respective percentiles were calculated for the 6MWT. The relationship between the RV/LV T2 blood pool ratio and the results from 6MWT were evaluated by Spearman's correlation coefficients and regression analyses. Inter-group differences were assessed by independent t-tests and univariate analysis of variance. RESULTS: The RV/LV T2 ratio moderately correlated with the percentiles of nominal distances in the 6MWT (r = 0.66) while ejection fraction, end-diastolic and end-systolic volumes showed no correlation (r = 0.09, 0.07 and - 0.01, respectively). In addition, there were significant differences in the RV/LV T2 ratio between patients with and without significant post-exercise dyspnea (p = 0.001). Regression analyses showed that RV/LV T2 ratio was an independent predictor of the distance walked and the presence of post-exercise dyspnea (p < 0.001). CONCLUSION: The proposed RV/LV T2 ratio, obtained by two simple measurements on a routinely acquired four-chamber T2 map, was superior to established parameters of cardiac function to predict exercise capacity and the presence of post-exercise dyspnea in patients with chronic heart failure.


Asunto(s)
Insuficiencia Cardíaca , Disfunción Ventricular Izquierda , Humanos , Estudios Retrospectivos , Tolerancia al Ejercicio , Valor Predictivo de las Pruebas , Imagen por Resonancia Magnética , Insuficiencia Cardíaca/diagnóstico por imagen , Volumen Sistólico , Función Ventricular Izquierda , Función Ventricular Derecha
8.
BMC Med Imaging ; 23(1): 187, 2023 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-37968580

RESUMEN

PURPOSE: Kidney volume is important in the management of renal diseases. Unfortunately, the currently available, semi-automated kidney volume determination is time-consuming and prone to errors. Recent advances in its automation are promising but mostly require contrast-enhanced computed tomography (CT) scans. This study aimed at establishing an automated estimation of kidney volume in non-contrast, low-dose CT scans of patients with suspected urolithiasis. METHODS: The kidney segmentation process was automated with 2D Convolutional Neural Network (CNN) models trained on manually segmented 2D transverse images extracted from low-dose, unenhanced CT scans of 210 patients. The models' segmentation accuracy was assessed using Dice Similarity Coefficient (DSC), for the overlap with manually-generated masks on a set of images not used in the training. Next, the models were applied to 22 previously unseen cases to segment kidney regions. The volume of each kidney was calculated from the product of voxel number and their volume in each segmented mask. Kidney volume results were then validated against results semi-automatically obtained by radiologists. RESULTS: The CNN-enabled kidney volume estimation took a mean of 32 s for both kidneys in a CT scan with an average of 1026 slices. The DSC was 0.91 and 0.86 and for left and right kidneys, respectively. Inter-rater variability had consistencies of ICC = 0.89 (right), 0.92 (left), and absolute agreements of ICC = 0.89 (right), 0.93 (left) between the CNN-enabled and semi-automated volume estimations. CONCLUSION: In our work, we demonstrated that CNN-enabled kidney volume estimation is feasible and highly reproducible in low-dose, non-enhanced CT scans. Automatic segmentation can thereby quantitatively enhance radiological reports.


Asunto(s)
Redes Neurales de la Computación , Tomografía Computarizada por Rayos X , Humanos , Tomografía Computarizada por Rayos X/métodos , Cintigrafía , Riñón/diagnóstico por imagen , Automatización , Procesamiento de Imagen Asistido por Computador/métodos
9.
Z Gastroenterol ; 61(3): 275-279, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36379462

RESUMEN

Gastric antral vascular ectasia (GAVE) syndrome is a rare but often challenging etiology of upper gastrointestinal bleeding (UGIB).We report on a 60-year-old patient with liver cirrhosis, GAVE syndrome and recurrent and refractory GAVE-related UGIB. During a 5-month hospital stay, the patient required a total of 82 packed red blood cells (pRBCs) and 23 gastroscopies. All endoscopic approaches, including multiple argon plasma coagulation and band ligation sessions, remained unsuccessful. Antrectomy was waived because of the high perioperative mortality risk in Child-Pugh B liver cirrhosis. TIPS insertion also failed to control the bleeding. Only continuous intravenous octreotide infusion slowed the bleeding, but this forced the patient to be hospitalized. After 144 inpatient days, administration of subcutaneous octreotide allowed the patient to be discharged. However, the patient continued to require two pRBCs every 2-3 weeks. Based on recently published data, we treated the patient with bevacizumab (anti-VEGF antibody) off-label at a dose of 7.5 mg/kg body weight every three weeks in nine single doses over six months. Since the first administration, the patient has remained transfusion-free, has not required hospitalization, and leads an active life, working full-time. He remains on octreotide, which has been reduced but not yet discontinued. Additionally, no adverse events were observed.Thus, in patients with liver cirrhosis and refractory GAVE-related hemorrhage, bevacizumab combined with subcutaneous octreotide should be considered as an effective and durable pharmacological treatment option.


Asunto(s)
Ectasia Vascular Antral Gástrica , Masculino , Humanos , Persona de Mediana Edad , Ectasia Vascular Antral Gástrica/complicaciones , Ectasia Vascular Antral Gástrica/cirugía , Octreótido/uso terapéutico , Bevacizumab , Resultado del Tratamiento , Cirrosis Hepática/complicaciones , Cirrosis Hepática/diagnóstico , Cirrosis Hepática/tratamiento farmacológico , Hemorragia Gastrointestinal/diagnóstico , Hemorragia Gastrointestinal/tratamiento farmacológico , Hemorragia Gastrointestinal/etiología
10.
BMC Med Educ ; 23(1): 80, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36726093

RESUMEN

INTRODUCTION: In emergency and critical-care medicine, focused cardiac ultrasound (FoCUS) is indispensable for assessing a patient's cardiac status. The aim of this study was to establish and validate a peer-to-peer-supported ultrasound course for learning FoCUS-specific skills during undergraduate studies at a German university. METHODS: A 1-day, 12 teaching units training course was developed for students in the clinical section of medical college, with content based on the current national guidelines. A total of 217 students participated in the study (97 in the course group and 120 in the control group). The course and the participants' subjective assessment of improved skills were evaluated using a questionnaire (7-point Likert scale; 7 = complete agreement and 1 = no agreement at all). Objective learning gains were assessed by tests before and after the course. These consisted of a test of figural intelligence (eight items) and a test of technical knowledge (13 items). RESULTS: The course participants experienced significant improvement (P < 0.001) from before to after the course, with a large effect size of η2part = 0.26. In addition, the course group had significantly better results (P < 0.001) than the control group in the post-test, with a medium to large effect size of η2part = 0.14. No significant differences (P = 0.27) were detected in the test section on figural intelligence. The evaluations showed that the participants had a high degree of satisfaction with the course approach, teaching materials, and tutors. There was also a positive increase in their subjective assessment of their own skills, including areas such as technical knowledge, ultrasound anatomy, and performance of the examination. CONCLUSION: The results of both the objective learning assessment and the subjective evaluations suggest that a FoCUS course originally intended for qualified physicians is equally suitable for students. With the development and provision of modern digital teaching media, even more students will be able to benefit from this approach in the future.


Asunto(s)
Educación de Pregrado en Medicina , Estudiantes de Medicina , Humanos , Curriculum , Estudios Prospectivos , Educación de Pregrado en Medicina/métodos , Ecocardiografía , Competencia Clínica , Enseñanza
11.
BMC Med Educ ; 23(1): 513, 2023 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-37461025

RESUMEN

BACKGROUND: A thorough knowledge of sonography is essential in clinical practice. Therefore, sonography training is increasingly incorporated into the medical school curriculum, entailing different course models. The question arises which model is most effective to convey sustained sonographic skills. METHODS: Two different peer-assisted learning (PAL) sonography course models were developed as part of a clinical prospective study. The course content was based on the national resident curriculum of the German Society for Ultrasound in Medicine (DEGUM). Model A consists of a 10-week course and model B of a two-day compact course. Each model entailed 20 teaching units (TU). A script was used to prepare for each unit. Two modified OSCE exams of the ultrasound skills (max = 50 points per exam) were performed during the last teaching unit to assess the competence level. For subjective self-assessment and model evaluation, a questionnaire with a 7-point Likert scale was employed. RESULTS: A total of 888 students of the 3rd year participated as part of a voluntary elective in the study (744 in model A and 144 in model B). In the exams, participants in model A (median 43 points) scored significantly higher than those in model B (median 39; p < 0.01). Participants in model A (mean 1.71 points) obtained significantly higher mean competency gain scores in subject knowledge than model B (mean 1.43 points; p < 0.01) participants. All participants were satisfied with the course concept (A: mean 1.68 vs. B: mean 1.78 points; p = 0.05), the teaching materials (A: mean 1.81 vs. B: mean 1.69 points; p = 0.52), and the tutor's didactic skills (A: mean 1.24 vs. B: mean 1.15 points; p < 0.05). CONCLUSION: These results suggest that sonography-specific competency may be obtained through different course models, with a model stretching over several weeks leading to a higher competence level. Further research should assess the long-term retention of the skills obtained in different models.


Asunto(s)
Educación de Pregrado en Medicina , Estudiantes de Medicina , Humanos , Evaluación Educacional , Estudios Prospectivos , Educación de Pregrado en Medicina/métodos , Competencia Clínica , Curriculum , Enseñanza
12.
BMC Med Educ ; 23(1): 723, 2023 Oct 03.
Artículo en Inglés | MEDLINE | ID: mdl-37789302

RESUMEN

BACKGROUND: Point-of-care Ocular Ultrasound (POCOUS) has gained importance in emergency medicine and intensive care in recent years. This work aimed to establish and evaluate a dedicated ultrasound education program for learning POCOUS-specific skills during medical studies at a university hospital. METHODS: The blended learning-based program (6 teaching units) based on recent scientific publications and recommendations was developed for students in the clinical part of their medical studies. Experts and trainers consisted of physicians from the Ear-Nose-Throat, radiology, ophthalmology and neurology specialties as well as university educational specialists. Lecture notes containing digital video links for preparation was produced as teaching material. In total, 33 students participated in the study. The education program, including the teaching materials, motivation and subjective gain in competency, was evaluated with the aid of a questionnaire (7-point Likert response format). Objective learning success was assessed on the basis of pre- and post-tests. These covered the skill areas: "anatomical basics", "ultrasound basics", "understanding of cross-sectional images", "normal findings" and "pathology recognition". RESULTS: In the objective assessment of image interpretation, the participants improved significantly (p < 0.001) from pre- to post-test with a large effect size (Cohen's d = 1.78, effect size r = 0.66). The evaluations revealed a high level of satisfaction with the course concept, teaching materials and the tutors. In addition, a high level of motivation was recorded in relation to continuing to study "ultrasound diagnostics" and "ophthalmologic diseases". A significant (p < 0.01) positive gain was also achieved in terms of the subjective assessment of competency. This covers areas such as expertise, sonographic anatomy and performing a POCOUS examination as well as recognizing retinal detachment, globe perforation and increased optic nerve sheath diameter. CONCLUSION: The results of this feasibility study show that medical students accept and support a POCOUS-specific education program and are able to develop a higher objective and subjective level of competency. Future transfer to other sites and larger groups of participants seems feasible.


Asunto(s)
Estudiantes de Medicina , Humanos , Sistemas de Atención de Punto , Curriculum , Ultrasonografía , Aprendizaje , Competencia Clínica
13.
J Hepatol ; 76(2): 446-457, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34555422

RESUMEN

In light of a global rise in obesity and type 2 diabetes, non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) represent an increasingly important underlying aetiology of hepatocellular carcinoma (HCC). HCCs arising from lipotoxicity-mediated chronic inflammation are characterised by several unique features: in contrast to virally driven HCC, up to 50% of NAFLD-HCC occurs in patients without cirrhosis and annual HCC incidence is comparatively low, complicating current surveillance strategies. On average, patients are older and are more frequently diagnosed at an advanced stage. While locoregional treatments are probably equally effective regardless of HCC aetiology, the picture is less clear for systemic therapy. Tyrosine kinase inhibitors are probably equally effective, while there have been initial signals that immune checkpoint inhibitors may be less effective in NAFLD-HCC than in viral HCC. Current international clinical practice guidelines for HCC do not consider aetiology, as there are insufficient data to draw specific conclusions or to recommend aetiology-specific modifications to the current management of patients with HCC. However, in light of the growing relevance of NAFLD-HCC, future clinical trials should assess whether HCC aetiology - and NAFLD/NASH in particular - influence the safety and efficacy of a given treatment.


Asunto(s)
Carcinoma Hepatocelular/terapia , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Carcinoma Hepatocelular/etiología , Progresión de la Enfermedad , Humanos , Hígado/patología , Neoplasias Hepáticas/etiología , Neoplasias Hepáticas/terapia , Trasplante de Hígado/métodos , Trasplante de Hígado/normas , Trasplante de Hígado/estadística & datos numéricos , Enfermedad del Hígado Graso no Alcohólico/terapia , Factores de Riesgo , Resultado del Tratamiento
14.
Opt Express ; 30(25): 44569-44579, 2022 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-36522879

RESUMEN

We designed an all-normal dispersion ytterbium rod-type fiber laser oscillator delivering picosecond pulses which are continuously tunable both in central wavelength and pulse duration. This system delivers self-mode-locked pulses with an average power up to 25 W. At a repetition rate of 78 MHz, it yields picosecond laser pulses, of which the central wavelength and pulse duration can be tuned between 1010 nm - 1060 nm and 4.5 ps - 1.8 ps, respectively. The tunability is obtained by adjusting the position and the width of a slit which acts as a spectral bandwidth filter, placed close to the center of a 4f-folded zero dispersion line inserted in the laser cavity. This oscillator delivers nearly Fourier limited pulses with at most a 1.2 time-bandwidth product. A numerical model accounts well for the behavior of this all-normal dispersion fiber oscillator.

15.
Eur Radiol ; 32(9): 6302-6313, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35394184

RESUMEN

OBJECTIVES: Splenic volume (SV) was proposed as a relevant prognostic factor for patients with hepatocellular carcinoma (HCC). We trained a deep-learning algorithm to fully automatically assess SV based on computed tomography (CT) scans. Then, we investigated SV as a prognostic factor for patients with HCC undergoing transarterial chemoembolization (TACE). METHODS: This retrospective study included 327 treatment-naïve patients with HCC undergoing initial TACE at our tertiary care center between 2010 and 2020. A convolutional neural network was trained and validated on the first 100 consecutive cases for spleen segmentation. Then, we used the algorithm to evaluate SV in all 327 patients. Subsequently, we evaluated correlations between SV and survival as well as the risk of hepatic decompensation during TACE. RESULTS: The algorithm showed Sørensen Dice Scores of 0.96 during both training and validation. In the remaining 227 patients assessed with the algorithm, spleen segmentation was visually approved in 223 patients (98.2%) and failed in four patients (1.8%), which required manual re-assessments. Mean SV was 551 ml. Survival was significantly lower in patients with high SV (10.9 months), compared to low SV (22.0 months, p = 0.001). In contrast, overall survival was not significantly predicted by axial and craniocaudal spleen diameter. Furthermore, patients with a hepatic decompensation after TACE had significantly higher SV (p < 0.001). CONCLUSION: Automated SV assessments showed superior survival predictions in patients with HCC undergoing TACE compared to two-dimensional spleen size estimates and identified patients at risk of hepatic decompensation. Thus, SV could serve as an automatically available, currently underappreciated imaging biomarker. KEY POINTS: • Splenic volume is a relevant prognostic factor for prediction of survival in patients with HCC undergoing TACE, and should be preferred over two-dimensional surrogates for splenic size. • Besides overall survival, progression-free survival and hepatic decompensation were significantly associated with splenic volume, making splenic volume a currently underappreciated prognostic factor prior to TACE. • Splenic volume can be fully automatically assessed using deep-learning methods; thus, it is a promising imaging biomarker easily integrable into daily radiological routine.


Asunto(s)
Carcinoma Hepatocelular , Quimioembolización Terapéutica , Neoplasias Hepáticas , Inteligencia Artificial , Carcinoma Hepatocelular/diagnóstico por imagen , Carcinoma Hepatocelular/terapia , Quimioembolización Terapéutica/métodos , Humanos , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/terapia , Estudios Retrospectivos , Bazo/diagnóstico por imagen , Bazo/patología , Resultado del Tratamiento
16.
Eur Radiol ; 32(5): 3152-3160, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-34950973

RESUMEN

OBJECTIVES: In response to the COVID-19 pandemic, many researchers have developed artificial intelligence (AI) tools to differentiate COVID-19 pneumonia from other conditions in chest CT. However, in many cases, performance has not been clinically validated. The aim of this study was to evaluate the performance of commercial AI solutions in differentiating COVID-19 pneumonia from other lung conditions. METHODS: Four commercial AI solutions were evaluated on a dual-center clinical dataset consisting of 500 CT studies; COVID-19 pneumonia was microbiologically proven in 50 of these. Sensitivity, specificity, positive and negative predictive values, and AUC were calculated. In a subgroup analysis, the performance of the AI solutions in differentiating COVID-19 pneumonia from other conditions was evaluated in CT studies with ground-glass opacities (GGOs). RESULTS: Sensitivity and specificity ranges were 62-96% and 31-80%, respectively. Negative and positive predictive values ranged between 82-99% and 19-25%, respectively. AUC was in the range 0.54-0.79. In CT studies with GGO, sensitivity remained unchanged. However, specificity was lower, and ranged between 15 and 53%. AUC for studies with GGO was in the range 0.54-0.69. CONCLUSIONS: This study highlights the variable specificity and low positive predictive value of AI solutions in diagnosing COVID-19 pneumonia in chest CT. However, one solution yielded acceptable values for sensitivity. Thus, with further improvement, commercial AI solutions currently under development have the potential to be integrated as alert tools in clinical routine workflow. Randomized trials are needed to assess the true benefits and also potential harms of the use of AI in image analysis. KEY POINTS: • Commercial AI solutions achieved a sensitivity and specificity ranging from 62 to 96% and from 31 to 80%, respectively, in identifying patients suspicious for COVID-19 in a clinical dataset. • Sensitivity remained within the same range, while specificity was even lower in subgroup analysis of CT studies with ground-glass opacities, and interrater agreement between the commercial AI solutions was minimal to nonexistent. • Thus, commercial AI solutions have the potential to be integrated as alert tools for the detection of patients with lung changes suspicious for COVID-19 pneumonia in a clinical routine workflow, if further improvement is made.


Asunto(s)
COVID-19 , Inteligencia Artificial , COVID-19/diagnóstico por imagen , Humanos , Pulmón/diagnóstico por imagen , Pandemias , Estudios Retrospectivos , SARS-CoV-2 , Tomografía Computarizada por Rayos X/métodos
17.
J Fish Biol ; 101(4): 797-810, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36056454

RESUMEN

The great hammerhead (Sphyrna mokarran) is a highly mobile, large-bodied shark primarily found in coastal-pelagic and semi-oceanic waters across a circumtropical range. It is a target or by-catch species in multiple fisheries, and as a result, rapid population declines have occurred in many regions. These declines have contributed to the species being assessed as globally critically endangered on the IUCN Red List. Although conservation and management measures have yielded promising results in some regions, such as the United States, high levels of at-vessel and post-release mortality remain a major concern to the species population recovery. This examined the vertical space use and thermal range of pop-off archival satellite-tagged S. mokarran in the western North Atlantic Ocean, expanding the understanding of the ecological niche of this species and providing insight into by-catch mitigation strategies for fisheries managers. The results showed that S. mokarran predominantly used shallow depths (75% of records <30 m) and had a narrow temperature range (89% of records between 23 and 28°C). Individual differences in depth use were apparent, and a strong diel cycle was observed, with sharks occupying significantly deeper depths during the daytime. Furthermore, two individuals were confirmed pregnant with one migrating from the Bahamas to South Carolina, U.S.A., providing further evidence of regional connectivity and parturition off the U.S. East Coast. The findings suggest that S. mokarran may be vulnerable to incidental capture in the western North Atlantic commercial longline fisheries due to substantial vertical overlap between the species and the gear. The results can be incorporated into conservation and management efforts to develop and/or refine mitigation measures focused on reducing the by-catch and associated mortality of this species, which can ultimately aide S. mokarran population recovery in areas with poor conservation status.


Asunto(s)
Tiburones , Animales , Explotaciones Pesqueras , Ecosistema , Océano Atlántico , Océanos y Mares
18.
Laryngorhinootologie ; 101(2): 156-175, 2022 02.
Artículo en Alemán | MEDLINE | ID: mdl-35098514

RESUMEN

Transcervical sonography has become an integral part of the diagnostic spectrum of otorhinolaryngology, as evidenced by its firm inclusion in continuing education catalogs and guidelines. For these reasons, the user should be aware of a basic understanding of ultrasound physics and of technical innovations. A standardized examination scheme with structured reporting and documentation is an elementary prerequisite to meet the daily clinical challenges and to be able to answer specific questions. In this educational article, we span from an introduction to structured examination techniques to a clinical update on sonography of the cephalic glands and cervical lymph nodes.


Asunto(s)
Neoplasias de Cabeza y Cuello , Cuello , Cabeza , Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Neoplasias de Cabeza y Cuello/patología , Humanos , Ganglios Linfáticos/patología , Metástasis Linfática/patología , Cuello/diagnóstico por imagen , Ultrasonografía
19.
Plant Physiol ; 183(2): 765-779, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32229608

RESUMEN

The circadian clock is a complex transcriptional network that regulates gene expression in anticipation of the day/night cycle and controls agronomic traits in plants. However, in crops, how the internal clock and day/night cues affect the transcriptome remains poorly understood. We analyzed the diel and circadian leaf transcriptomes in the barley (Hordeum vulgare) cultivar 'Bowman' and derived introgression lines harboring mutations in EARLY FLOWERING3 (ELF3), LUX ARRHYTHMO1 (LUX1), and EARLY MATURITY7 (EAM7). The elf3 and lux1 mutants exhibited abolished circadian transcriptome oscillations under constant conditions, whereas eam7 maintained oscillations of ≈30% of the circadian transcriptome. However, day/night cues fully restored transcript oscillations in all three mutants and thus compensated for a disrupted oscillator in the arrhythmic barley clock mutants elf3 and lux1 Nevertheless, elf3, but not lux1, affected the phase of the diel oscillating transcriptome and thus the integration of external cues into the clock. Using dynamical modeling, we predicted a structure of the barley circadian oscillator and interactions of its individual components with day/night cues. Our findings provide a valuable resource for exploring the function and output targets of the circadian clock and for further investigations into the diel and circadian control of the barley transcriptome.


Asunto(s)
Relojes Circadianos/genética , Ritmo Circadiano/fisiología , Hordeum/genética , Hordeum/fisiología , Ritmo Circadiano/genética , Regulación de la Expresión Génica de las Plantas/genética , Regulación de la Expresión Génica de las Plantas/fisiología , Transcriptoma/genética
20.
Hepatobiliary Pancreat Dis Int ; 20(3): 262-270, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32861577

RESUMEN

BACKGROUND: Intrahepatic cholangiocarcinoma (ICC) still has a poor long-term outcome, even after complete resection. We investigated different parameters gathered in preoperative imaging and analyzed their influence on resectability, recurrence, and survival. METHODS: All patients who underwent exploration due to ICC between January 2008 and June 2018 were analyzed retrospectively. Kaplan-Meier model, log-rank test and Cox regression were used. RESULTS: Out of 184 patients, 135 (73.4%) underwent curative intended resection. Median overall survival (OS) was 22.2 months with a consecutive 1-, 3- and 5-year OS of 73%, 29%, and 17%. Median recurrence-free survival (RFS) was 9.3 months with a consecutive 1-, 3- and 5-year RFS of 36%, 15%, and 11%. Site of tumor, parenchymal localization, tumor configuration/dissemination, and estimated tumor volume had significant influence on resectability. Univariate analyses showed that site of tumor, tumor configuration/dissemination, number of nodules, and estimated tumor volume had predictive values for OS and RFS. Together with tumor size the preoperative prediction (POP) score was created showing significance for OS and RFS (all P < 0.001). In multivariate analysis, POP score (HR = 1.779; 95% CI: 1.268-2.495; P = 0.001), T stage (HR = 1.255; 95% CI: 1.040-1.514; P = 0.018) and N stage (HR = 1.334; 95% CI: 1.081-1.645; P = 0.007) were the independent predictors for OS. For RFS, POP score (HR = 1.733; 95% CI: 1.300-2.311; P < 0.001) and M stage (HR = 3.036; 95% CI: 1.376-6.697; P = 0.006) were the independent predictors. CONCLUSIONS: The POP score showed to have a highly significant influence on OS and RFS. The score is easy to assess through preoperative imaging. For patients in the high risk group at least staging laparoscopy or preoperative chemotherapy should be evaluated, because they showed equal outcome compared to the irresectable group.


Asunto(s)
Neoplasias de los Conductos Biliares , Colangiocarcinoma , Neoplasias de los Conductos Biliares/diagnóstico por imagen , Neoplasias de los Conductos Biliares/cirugía , Conductos Biliares Intrahepáticos/diagnóstico por imagen , Conductos Biliares Intrahepáticos/cirugía , Colangiocarcinoma/diagnóstico por imagen , Colangiocarcinoma/cirugía , Humanos , Pronóstico , Estudios Retrospectivos
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