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1.
Ultrasound Med Biol ; 48(12): 2355-2378, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36058799

RESUMEN

The World Federation of Ultrasound in Medicine and Biology (WFUMB) is addressing the issue of incidental findings with a series of position papers to give advice on characterization and management. The biliary system (gallbladder and biliary tree) is the third most frequent site for incidental findings. This first part of the position paper on incidental findings of the biliary system is related to general aspects, gallbladder polyps and other incidental findings of the gallbladder wall. Available evidence on prevalence, diagnostic work-up, malignancy risk, follow-up and treatment is summarized with a special focus on ultrasound techniques. Multiparametric ultrasound features of gallbladder polyps and other incidentally detected gallbladder wall pathologies are described, and their inclusion in assessment of malignancy risk and decision- making on further management is suggested.


Asunto(s)
Enfermedades de la Vesícula Biliar , Neoplasias de la Vesícula Biliar , Pólipos , Humanos , Vesícula Biliar/diagnóstico por imagen , Hallazgos Incidentales , Neoplasias de la Vesícula Biliar/diagnóstico por imagen , Enfermedades de la Vesícula Biliar/diagnóstico por imagen , Enfermedades de la Vesícula Biliar/patología , Pólipos/diagnóstico por imagen , Ultrasonografía , Conductos Biliares/diagnóstico por imagen , Conductos Biliares/patología , Biología
2.
Ultrasound Med Biol ; 48(5): 912-923, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35227531

RESUMEN

Contrast-enhanced ultrasound (CEUS) is used in various medical specialties as a diagnostic imaging tool and for procedural guidance. Experience in the procedure is currently attained via supervised clinical practice that is challenged by patient availability and risks. Prior simulation-based training and subsequent assessment could improve and ensure competence before performance on patients, but no simulator currently exists. Immersive virtual reality (IVR) is a new promising simulation tool that can replicate complex interactions and environments that are unfeasible to achieve by traditional simulators. This study was aimed at developing an IVR simulation-based test for core CEUS competencies and gathering validity evidence for the test in accordance with Messick's framework. The test was developed by IVR software specialists and clinical experts in CEUS and medical education and imitated a CEUS examination of a patient with a focal liver lesion with emphasis on the pre-contrast preparations. Twenty-five medical doctors with varying CEUS experience were recruited as test participants, and their results were used to analyze test quality and to establish a pass/fail standard. The final test of 23 test items had good internal reliability (Cronbach's α = 0.85) and discriminatory abilities. The risks of false positives and negatives (9.1% and 23.6%, respectively) were acceptable for the test to be used as a certification tool prior to supervised clinical training in CEUS.


Asunto(s)
Entrenamiento Simulado , Realidad Virtual , Competencia Clínica , Simulación por Computador , Humanos , Reproducibilidad de los Resultados , Entrenamiento Simulado/métodos , Ultrasonografía
3.
Ultrasound Med Biol ; 48(2): 248-256, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34815128

RESUMEN

Contrast-enhanced ultrasound (CEUS) is an imaging modality applied in a broad field of medical specialties for diagnostic uses, guidance during biopsy procedures and ablation therapies and sonoporation therapy. Appropriate training and assessment of theoretical and practical competencies are recommended before practicing CEUS, but no validated assessment tools exist. This study was aimed at developing a theoretical multiple-choice question-based test for core CEUS competencies and gathering validity evidence for the test. An expert team developed the test via a Delphi process. The test was administered to medical doctors with varying CEUS experience, and the results were used to evaluate test items, internal-consistency reliability, ability to distinguish between different proficiency levels and to establish a pass/fail score. Validity evidence was gathered according to Messick's framework. The final test with 47 test items could distinguish between operators with and without CEUS experience with acceptable reliability. The pass/fail score led to considerable risk of false positives and negatives. The test may be used as an entry test before learning practical CEUS competencies but is not recommended for certification purposes because of the risk of false positives and negatives.


Asunto(s)
Competencia Clínica , Medios de Contraste , Reproducibilidad de los Resultados , Ultrasonografía
4.
Ultrasound Med Biol ; 46(9): 2287-2292, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32553690

RESUMEN

Contrast-enhanced ultrasound (CEUS) is dependent on the observer's competencies, and thus, appropriate education and testing of individual competency is essential. The current international curriculum in CEUS is methodologically weak and lacks validated competency assessment tests. In this study, we aimed to develop a syllabus for core competencies in CEUS using the Delphi process and an international panel of experts. A core writing group constructed an initial draft of the syllabus based on the existing literature. Eight international experts in CEUS or medical education were recruited as Delphi panelists. The draft underwent iterative and anonymous Delphi rounds until a pre-defined level of consensus was reached. The final syllabus consisted of 16 items, which were indexed in two main domains and in procedural order. An expert-generated proposal for a syllabus of core CEUS competencies has been constructed via the Delphi process and may serve as framework for future development of a CEUS curriculum, including competency assessment tests.


Asunto(s)
Competencia Clínica , Medios de Contraste , Ultrasonografía/métodos , Ultrasonografía/normas , Curriculum , Técnica Delphi , Humanos
5.
Australas J Ultrasound Med ; 21(2): 87-95, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-34760508

RESUMEN

INTRODUCTION: Liver metastases from colorectal cancer are common and ablation therapy is a favourable treatment option for selected patients not suited for surgical resection. This study aimed to systematically review the literature and present prognostic factors associated with survival and local recurrence after percutaneous ultrasound-guided ablation treatment. MATERIALS AND METHODS: This review is reported according to the PRISMA. PubMed, Embase and Scopus were searched and records were independently screened by two authors, initially on title and abstract and subsequently on full-text basis. The quality of the studies was assessed using the Newcastle-Ottawa quality assessment scale. RESULTS: Of 2.882 records screened, 18 studies were included. The median survival was 23 months. One-year survival was median 95% and 3-year survival was median 58%. Complete ablation response and adjuvant chemotherapy produce considerably improved survival and low local recurrence rate outcomes. CONCLUSION: Percutaneous ultrasound-guided ablation technique for colorectal liver metastases provides impressive survival rates for patients not suited for surgical resection. However, there are some factors related to poorer prognosis, which may be considered when selecting patients.

6.
Ultrasound Med Biol ; 39(2): 187-210, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23137926

RESUMEN

Initially, a set of guidelines for the use of ultrasound contrast agents was published in 2004 dealing only with liver applications. A second edition of the guidelines in 2008 reflected changes in the available contrast agents and updated the guidelines for the liver, as well as implementing some non-liver applications. Time has moved on, and the need for international guidelines on the use of CEUS in the liver has become apparent. The present document describes the third iteration of recommendations for the hepatic use of contrast enhanced ultrasound (CEUS) using contrast specific imaging techniques. This joint WFUMB-EFSUMB initiative has implicated experts from major leading ultrasound societies worldwide. These liver CEUS guidelines are simultaneously published in the official journals of both organizing federations (i.e., Ultrasound in Medicine and Biology for WFUMB and Ultraschall in der Medizin/European Journal of Ultrasound for EFSUMB). These guidelines and recommendations provide general advice on the use of all currently clinically available ultrasound contrast agents (UCA). They are intended to create standard protocols for the use and administration of UCA in liver applications on an international basis and improve the management of patients worldwide.


Asunto(s)
Algoritmos , Medios de Contraste/normas , Aumento de la Imagen/normas , Neoplasias Hepáticas/diagnóstico por imagen , Guías de Práctica Clínica como Asunto , Ultrasonografía/normas , Humanos , Internacionalidad
7.
Eur J Radiol ; 69(1): 93-101, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17961948

RESUMEN

PURPOSE: To prospectively investigate the effect on signal intensity (SI) of healthy breast parenchyma on magnetic resonance mammography (MRM) when doubling the contrast dose from 0.1 to 0.2 mmol/kg bodyweight. MATERIALS AND METHODS: Informed consent and institutional review board approval were obtained. Twenty-five healthy female volunteers (median age: 24 years (range: 21-37 years) and median bodyweight: 65 kg (51-80 kg)) completed two dynamic MRM examinations on a 0.6T open scanner. The inter-examination time was 24 h (23.5-25 h). The following sequences were applied: axial T2W TSE and an axial dynamic T1W FFED, with a total of seven frames. At day 1, an i.v. gadolinium (Gd) bolus injection of 0.1 mmol/kg bodyweight (Omniscan) (low) was administered. On day 2, the contrast dose was increased to 0.2 mmol/kg (high). Injection rate was 2 mL/s (day 1) and 4 mL/s (day 2). Any use of estrogen containing oral contraceptives (ECOC) was recorded. Post-processing with automated subtraction, manually traced ROI (region of interest) and recording of the SI was performed. A random coefficient model was applied. RESULTS: We found an SI increase of 24.2% and 40% following the low and high dose, respectively (P<0.0001); corresponding to a 65% (95% CI: 37-99%) SI increase, indicating a moderate saturation. Although not statistically significant (P=0.06), the results indicated a tendency, towards lower maximal SI in the breast parenchyma of ECOC users compared to non-ECOC users. CONCLUSION: We conclude that the contrast dose can be increased from 0.1 to 0.2 mmol/kg bodyweight, if a better contrast/noise relation is desired but increasing the contrast dose above 0.2 mmol/kg bodyweight is not likely to improve the enhancement substantially due to the moderate saturation observed. Further research is needed to determine the impact of ECOC on the relative enhancement ratio, and further studies are needed to determine if a possible use of ECOC should be considered a compromising factor, if an MRM is indicated in a young woman.


Asunto(s)
Mama/anatomía & histología , Gadolinio DTPA/administración & dosificación , Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Imagen por Resonancia Magnética/métodos , Modelos Biológicos , Adulto , Simulación por Computador , Medios de Contraste/administración & dosificación , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Valores de Referencia , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
8.
Eur J Radiol ; 65(2): 279-85, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17467219

RESUMEN

PURPOSE: To quantify the border versus centre enhancement of malignant breast tumours on dynamic magnetic resonance mammography. MATERIALS AND METHODS: Fifty-two women diagnosed with primary breast cancer underwent dynamic magnetic resonance mammography (Omniscan 0.2 mmol/kg bodyweight) on a midfield scanner (0.6 T), prior to surgery. The following five variables were recorded from the border and centre regions of the tumours: Early Enhancement, Time to Peak, Wash-in rate, Wash-out rate and Area under Curve. Information on histology type, oestrogen and progesterone receptor status was collected. Statistical analysis was performed in SAS 9.1 as paired samples t-tests. RESULTS: Fifty of 52 malignant tumours displayed a faster Early Enhancement in the border region compared to the centre (p<0.0001). Significant differences between the border and centre values were found for Time to Peak, Wash-in rate, Wash-out rate and Area under Curve. Hormone receptor positive tumours displayed an over-all highly significant difference between border and centre enhancement, whereas no significant differences for any of the five variables were recorded in neither oestrogen nor progesterone hormone receptor negative tumours. CONCLUSION: The border/centre enhancement difference in malignant breast tumours is easily visualized on midfield dynamic magnetic resonance mammography. The dynamic behaviour is significantly correlated to histological features and receptor status of the tumours.


Asunto(s)
Neoplasias de la Mama/patología , Medios de Contraste/farmacocinética , Gadolinio DTPA/farmacocinética , Imagen por Resonancia Magnética/métodos , Adulto , Anciano , Anciano de 80 o más Años , Área Bajo la Curva , Neoplasias de la Mama/metabolismo , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Persona de Mediana Edad
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