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1.
Proc Natl Acad Sci U S A ; 121(13): e2313239121, 2024 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-38498710

RESUMEN

High-entropy alloy nanoparticles (HEANs) possessing regulated defect structure and electron interaction exhibit a guideline for constructing multifunctional catalysts. However, the microstructure-activity relationship between active sites of HEANs for multifunctional electrocatalysts is rarely reported. In this work, HEANs distributed on multi-walled carbon nanotubes (HEAN/CNT) are prepared by Joule heating as an example to explain the mechanism of trifunctional electrocatalysis for oxygen reduction, oxygen evolution, and hydrogen evolution reaction. HEAN/CNT excels with unmatched stability, maintaining a 0.8V voltage window for 220 h in zinc-air batteries. Even after 20 h of water electrolysis, its performance remains undiminished, highlighting exceptional endurance and reliability. Moreover, the intrinsic characteristics of the defect structure and electron interaction for HEAN/CNT are investigated in detail. The electrocatalytic mechanism of trifunctional electrocatalysis of HEAN/CNT under different conditions is identified by in situ monitoring and theoretical calculation. Meanwhile, the electron interaction and adaptive regulation of active sites in the trifunctional electrocatalysis of HEANs were further verified by density functional theory. These findings could provide unique ideas for designing inexpensive multifunctional high-entropy electrocatalysts.

2.
Small ; 20(7): e2305390, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37797192

RESUMEN

A FeCo/DA@NC catalyst with the well-defined FeCoN6 moiety is customized through a novel and ultrafast Joule heating technique. This catalyst demonstrates superior oxygen reduction reaction activity and stability in an alkaline environment. The power density and charge-discharge cycling of znic-air batteries driven by FeCo/DA@NC also surpass those of Pt/C catalyst. The source of the excellent oxygen reduction reaction activity of FeCo/DA@NC originates from the significantly changed charge environment and 3d orbital spin state. These not only improve the bonding strength between active sites and oxygen-containing intermediates, but also provide spare reaction sites for oxygen-containing intermediates. Moreover, various in situ detection techniques reveal that the rate-determining step in the four-electron oxygen reduction reaction is *O2 protonation. This work provides strong support for the precise design and rapid preparation of bimetallic catalysts and opens up new ideas for understanding orbital interactions during oxygen reduction reactions.

3.
AJR Am J Roentgenol ; 220(1): 50-62, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-35895298

RESUMEN

BACKGROUND. Digital breast tomosynthesis (DBT) has led to increased detection of architectural distortion (AD). Management of patients with multiple areas of AD is not established. OBJECTIVE. The purpose of this article is to compare pathologic outcomes between single and multiple areas of AD identified on DBT. METHODS. This retrospective study included 402 patients (mean age, 56 years) who underwent image-guided core needle biopsy of AD visualized on DBT between April 7, 2017, and April 16, 2019. Patients were classified as having a single or multiple areas of AD according to the presence of distinct areas of AD described in the clinical radiology reports. The pathologic diagnosis for each AD was on the basis of the most aggressive pathology identified on either biopsy or surgical excision, if performed. Patients with single and multiple areas of AD were compared. RESULTS. The sample included 372 patients with a single AD (145 benign, 121 high risk, 105 malignant, one other) and 30 patients with multiple visualized ADs, including 66 biopsied ADs (10 benign, 35 high risk, 21 malignant). At pathologic assessment on a per-lesion basis, multiple compared with single ADs showed higher frequency of high-risk pathology (53.0% vs 32.5%, p = .002) but no difference in frequency of malignancy (31.8% vs 28.2%, p = .56). In multivariable analysis of a range of patient-related characteristics, the presence of single versus multiple areas of AD was not independently associated with malignancy (p = .51). In patients with multiple areas of AD, the most aggressive pathology (benign, high risk, or malignant) across all ADs was not associated with the number of ADs (p = .73). In 8 of 24 patients with at least two ipsilateral biopsied ADs, the ipsilateral areas varied in terms of most aggressive pathology; in 5 of 10 patients with contralateral biopsied ADs, the contralateral areas varied in most aggressive pathology. CONCLUSION. The presence of multiple areas of AD, compared with a single AD, was significantly more likely to yield high-risk pathology but was not significantly different in yield of malignancy. In patients with multiple ADs, multiple ipsilateral or contralateral ADs commonly varied in pathologic classification (benign, high risk, or malignant). CLINICAL IMPACT. These findings may help guide management of AD visualized by DBT, including multiple ADs. For patients with multiple areas of AD, biopsy of all areas may be warranted given variation in pathologic diagnoses.


Asunto(s)
Neoplasias de la Mama , Paraganglioma , Humanos , Persona de Mediana Edad , Femenino , Estudios Retrospectivos , Mamografía/métodos , Biopsia Guiada por Imagen/métodos , Agujas , Neoplasias de la Mama/diagnóstico por imagen , Mama/diagnóstico por imagen
4.
Inorg Chem ; 62(50): 20655-20665, 2023 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-37523384

RESUMEN

The solution chemistry of the hydrolytic, early-transition-metal ions Ti4+ and Sc3+ represents a coordination chemistry challenge with important real-world implications, specifically in the context of 44Ti/44Sc and 45Ti/NatSc radiochemical separations. Unclear speciation of the solid and solution phases and tertiary mixtures of mineral acid, organic chelators, and solid supports are common confounds, necessitating tedious screening of multiple variables. Herein we describe how thermodynamic speciation data in solution informs the design of new solid-phase chelation approaches enabling separations of Ti4+ and Sc3+. The ligands catechol (benzene-1,2-diol) and deferiprone [3-hydroxy-1,2-dimethyl-4(1H)-pyridone] bind Ti4+ at significantly more acidic conditions (2-4 pH units) than Sc3+. Four chelating resins were synthesized using either catechol or deferiprone with two different solid supports. Of these, deferiprone appended to carboxylic acid polymer-functionalized silica (CA-Def) resin exhibited excellent binding affinity for Ti4+ across a wide range of HCl concentrations (1.0-0.001 M), whereas Sc3+ was only retained in dilute acidic conditions (0.01-0.001 M HCl). CA-Def resin produced separation factors of >100 (Ti/Sc) in 0.1-0.4 M HCl, and the corresponding Kd values (>1000) show strong retention of Ti4+. A model 44Ti/44Sc generator was produced, showing 65 ± 3% yield of 44Sc in 200 µL of 0.2 M HCl with a significant 44Ti breakthrough of 0.1%, precluding use in its current form. Attempts, however, removed natSc in loading fractions and a dilute (0.4 M HCl) wash and recovered 80% of the loaded 45Ti activity in 400 µL of 6 M HCl. The previously validated 45Ti chelator TREN-CAM was used for comparative proof-of-concept reactions with the CA-Def eluent (in HCl) and literature-reported hydroxamate-based resin eluents (in citric acid). CA-Def shows improved radiolabeling efficiency with an apparent molar activity (AMA) of 0.177 mCi nmol-1, exceeding the established methods (0.026 mCi nmol-1) and improving the separation and recovery of 45Ti for positron emission tomography imaging applications.

5.
Angew Chem Int Ed Engl ; 62(27): e202303871, 2023 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-37133306

RESUMEN

A novel type of covalent organic frameworks has been developed by assembling definite cobalt-nitrogen-carbon configurations onto carbon nanotubes using linkers that have varying electronic effects. This innovative approach has resulted in an efficient electrocatalyst for oxygen reduction, which is understood by a combination of in situ spectroelectrochemistry and the bond order theorem. The strong interaction between the electron-donating carbon nanotubes and the electron-accepting linker mitigates the trend of charge loss at cobalt sites, while inducing the generation of high spin state. This enhances the adsorption strength and electron transfer between the cobalt center and reactants/intermediates, leading to an improved oxygen reduction capability. This work not only presents an effective strategy for developing efficient non-noble metal electrocatalysts through reticular chemistry, but also provides valuable insights into regulating the electronic configuration and charge behavior of active sites in designing high-performance electrocatalysts.

6.
Radiology ; 298(1): 60-70, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33201788

RESUMEN

Background The Eastern Cooperative Oncology Group and American College of Radiology Imaging Network Cancer Research Group A6702 multicenter trial helped confirm the potential of diffusion-weighted MRI for improving differential diagnosis of suspicious breast abnormalities and reducing unnecessary biopsies. A prespecified secondary objective was to explore the relative value of different approaches for quantitative assessment of lesions at diffusion-weighted MRI. Purpose To determine whether alternate calculations of apparent diffusion coefficient (ADC) can help further improve diagnostic performance versus mean ADC values alone for analysis of suspicious breast lesions at MRI. Materials and Methods This prospective trial (ClinicalTrials.gov identifier: NCT02022579) enrolled consecutive women (from March 2014 to April 2015) with a Breast Imaging Reporting and Data System category of 3, 4, or 5 at breast MRI. All study participants underwent standardized diffusion-weighted MRI (b = 0, 100, 600, and 800 sec/mm2). Centralized ADC measures were performed, including manually drawn whole-lesion and hotspot regions of interest, histogram metrics, normalized ADC, and variable b-value combinations. Diagnostic performance was estimated by using the area under the receiver operating characteristic curve (AUC). Reduction in biopsy rate (maintaining 100% sensitivity) was estimated according to thresholds for each ADC metric. Results Among 107 enrolled women, 81 lesions with outcomes (28 malignant and 53 benign) in 67 women (median age, 49 years; interquartile range, 41-60 years) were analyzed. Among ADC metrics tested, none improved diagnostic performance versus standard mean ADC (AUC, 0.59-0.79 vs AUC, 0.75; P = .02-.84), and maximum ADC had worse performance (AUC, 0.52; P < .001). The 25th-percentile ADC metric provided the best performance (AUC, 0.79; 95% CI: 0.70, 0.88), and a threshold using median ADC provided the greatest reduction in biopsy rate of 23.9% (95% CI: 14.8, 32.9; 16 of 67 BI-RADS category 4 and 5 lesions). Nonzero minimum b value (100, 600, and 800 sec/mm2) did not improve the AUC (0.74; P = .28), and several combinations of two b values (0 and 600, 100 and 600, 0 and 800, and 100 and 800 sec/mm2; AUC, 0.73-0.76) provided results similar to those seen with calculations of four b values (AUC, 0.75; P = .17-.87). Conclusion Mean apparent diffusion coefficient calculated with a two-b-value acquisition is a simple and sufficient diffusion-weighted MRI metric to augment diagnostic performance of breast MRI compared with more complex approaches to apparent diffusion coefficient measurement. © RSNA, 2020 Online supplemental material is available for this article.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Imagen de Difusión por Resonancia Magnética/métodos , Adulto , Anciano , Mama/diagnóstico por imagen , Diagnóstico Diferencial , Femenino , Humanos , Persona de Mediana Edad , Estudios Prospectivos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Sociedades Médicas , Adulto Joven
7.
BMC Infect Dis ; 21(1): 644, 2021 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-34225647

RESUMEN

BACKGROUND: Available data on influenza burden across Southeast Asia are largely limited to pediatric populations, with inconsistent findings. METHODS: We conducted a multicenter, hospital-based active surveillance study of adults in Malaysia with community-acquired pneumonia (CAP), acute exacerbation of chronic obstructive pulmonary disease (AECOPD) and acute exacerbation of asthma (AEBA), who had influenza-like illness ≤10 days before hospitalization. We estimated the rate of laboratory-confirmed influenza and associated complications over 13 months (July 2018-August 2019) and described the distribution of causative influenza strains. We evaluated predictors of laboratory-confirmed influenza and severe clinical outcomes using multivariate analysis. RESULTS: Of 1106 included patients, 114 (10.3%) were influenza-positive; most were influenza A (85.1%), with A/H1N1pdm09 being the predominant circulating strain during the study following a shift from A/H3N2 from January-February 2019 onwards. In multivariate analyses, an absence of comorbidities (none versus any comorbidity [OR (95%CI), 0.565 (0.329-0.970)], p = 0.038) and of dyspnea (0.544 (0.341-0.868)], p = 0.011) were associated with increased risk of influenza positivity. Overall, 184/1106 (16.6%) patients were admitted to intensive care or high-dependency units (ICU/HDU) (13.2% were influenza positive) and 26/1106 (2.4%) died (2.6% were influenza positive). Males were more likely to have a severe outcome (ICU/HDU admission or death). CONCLUSIONS: Influenza was a significant contributor to hospitalizations associated with CAP, AECOPD and AEBA. However, it was not associated with ICU/HDU admission in this population. Study registration, NMRR ID: NMRR-17-889-35,174.


Asunto(s)
Asma/complicaciones , Infecciones Comunitarias Adquiridas/complicaciones , Subtipo H3N2 del Virus de la Influenza A , Gripe Humana/complicaciones , Neumonía/complicaciones , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Adulto , Anciano , Preescolar , Hospitalización , Humanos , Unidades de Cuidados Intensivos , Masculino , Persona de Mediana Edad
8.
Breast J ; 24(3): 343-349, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29139591

RESUMEN

To evaluate the MR appearance of noncalcified ductal carcinoma in situ (DCIS), with comparison to calcified DCIS. A retrospective, IRB-approved review of all DCIS diagnosed via MR biopsy between 2007 and 2011 was performed. DCIS was categorized as noncalcified based on the absence of calcifications on mammography and specimen radiography. MR morphology (focus, mass, nonmass enhancement [NME]) and enhancement kinetics (initial and delayed) for noncalcified DCIS were recorded and compared based on nuclear grade (1-3), size (<1.5 cm, 1.5-5 cm, >5 cm), and presence of necrosis. Imaging features of noncalcified and calcified DCIS were also compared. 115 cases of MR biopsy-proven DCIS were identified: 65 (56%) noncalcified and 50 (44%) calcified. For noncalcified DCIS, NME morphology was more common than mass or focus (60% vs 30.8% and 9.2%). There was a significant association between morphology and enhancement kinetics, with NME more likely demonstrating medium and persistent kinetics, and foci or masses demonstrating rapid and plateau or washout kinetics (P < .05). There was also a significant association between morphology and nuclear grade, with NME more likely seen with grade 3 DCIS (P = .024), and between size and initial enhancement, with lesions <1.5 cm more likely to have rapid initial enhancement (P = .0036). No significant difference was identified between calcified and noncalcified DCIS in terms of morphology, enhancement characteristics, nuclear grade, or presence of necrosis. The MR appearance of noncalcified DCIS closely mirrors that of calcified DCIS. Recognizing these imaging features may allow for improved identification of this MRI-detected abnormality, even in the absence of calcifications.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Calcinosis/diagnóstico por imagen , Carcinoma Intraductal no Infiltrante/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Neoplasias de la Mama/patología , Calcinosis/patología , Carcinoma Intraductal no Infiltrante/patología , Femenino , Humanos , Aumento de la Imagen , Biopsia Guiada por Imagen , Persona de Mediana Edad , Necrosis/diagnóstico por imagen , Necrosis/patología , Cuidados Preoperatorios
9.
AJR Am J Roentgenol ; 208(1): 208-213, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27680714

RESUMEN

OBJECTIVE: The purpose of this study is to identify the optimal screening mammography recall rate range on the basis of cancer detection rates among breast imaging specialists at an academic institution. MATERIALS AND METHODS: Medical outcome audit data collected in accordance with the Mammography Quality Standards Act from September 1, 2007, through August 31, 2012, were reviewed. Cancer detection rates were calculated from 984 screen-detected cancers identified in 188,959 total digital screening mammograms. The percentages of minimally invasive and early-stage cancers were also calculated. The 75 annual recall rates were analyzed two ways. First, they were separated into recall groups to assess cancer detection rate variation by the recall categories using rate ratios: less than 10%, 10% to less than 12%, 12% to less than 14%, and 14% or higher. Next, a linear regression with bootstrap bias correction was performed to assess changes in cancer detection rate with each unit increase in the recall rate up to 20%, with the recall category of less than 7% taken as reference. Annual cancer detection rates for a physician were grouped according to annual percentage recall rate. RESULTS: Statistically significantly higher cancer detection rates were seen for recall rates 12% or higher, with rate ratios of 1.75 (95% CI, 1.40-2.19) and 2.06 (95% CI, 1.72-2.46) for the recall groups 12% to less than 14% and 14% and higher, respectively, compared with the less than 10% group. When taking the category 12% to less than 14% as the reference, there were no statistically significant differences between recall groups 12% to less than 14% and 14% or higher in cancer detection rate. A statistically significant increase in the cancer detection rate with each unit increase in the recall rate was seen only for recall rates 12% or higher. CONCLUSION: These observations suggest that the sweet spot for optimal cancer detection is in the recall rate range 12% to less than 14% with the incremental benefit above this to be relatively small. A recall rate less than 10% may be too low.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/epidemiología , Detección Precoz del Cáncer/estadística & datos numéricos , Detección Precoz del Cáncer/normas , Mamografía/estadística & datos numéricos , Mamografía/normas , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/prevención & control , Chicago/epidemiología , Reacciones Falso Negativas , Femenino , Humanos , Persona de Mediana Edad , Variaciones Dependientes del Observador , Guías de Práctica Clínica como Asunto , Garantía de la Calidad de Atención de Salud/métodos , Garantía de la Calidad de Atención de Salud/estadística & datos numéricos , Control de Calidad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Estados Unidos , Adulto Joven
10.
J Breast Imaging ; 6(1): 80-85, 2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38243860

RESUMEN

OBJECTIVE: To evaluate breast imaging fellowship program directors' perspectives on the virtual interview process. METHODS: A 20-question survey constructed by members of the Fellowship Match Committee of the Society of Breast Imaging was distributed to all 99 breast imaging program directors registered with the Society. An initial e-mail with a link to the survey was distributed on September 9, 2022, and the survey was closed on October 1, 2022. Results were compiled and a descriptive statistical analysis was performed utilizing Microsoft Excel. RESULTS: There were 63 total responses (63/99, 64% response rate). There was a wide distribution in both the number of applications received and the number of interviews each program offered. Just under a fifth (12/63, 19%) of programs received 1 to 5 applications, whereas a quarter (16/63, 25%) received over 40 applications. In contrast, over a quarter (17/63, 27%) of programs interviewed 1 to 5 applicants, and only a small number (3/63, 5%) interviewed over 40 applicants. When reporting what worked best with the virtual interview process, the responses fell into the following 4 categories: efficiency, flexibility, virtual format, or other. When reporting what did not work well, the most common response (14/37, 38%) was conveying the atmosphere of the program in the virtual setting. CONCLUSION: This study provides an assessment of the virtual interview experience from the perspective of breast imaging fellowship programs, which may be useful in optimizing future interview experiences for programs and applicants.


Asunto(s)
Becas , Selección de Personal , Selección de Personal/métodos , Proyectos de Investigación , Encuestas y Cuestionarios
11.
J Breast Imaging ; 6(2): 192-202, 2024 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-38217375

RESUMEN

The radiologist's ability to effectively communicate with patients is crucial in breast imaging. Having to tell a patient that she or he requires a biopsy procedure or has a new diagnosis of breast cancer is both a challenging task and a daily reality for many practicing breast radiologists. Despite this, communication in breast imaging is often not formally taught in most training programs, leading many breast radiologists to obtain their skills through on-the-job experience. We discuss the importance of effective communication with patients and a breast imaging-specific method for delivering bad news, adapted from approaches used in medical oncology. A conversation "script" or guide is provided along with the rationale for how to best handle these difficult conversations. Lastly, we review how to teach effective communication to those in training using our breast imaging fellowship program and recent survey results as an example.


Asunto(s)
Neoplasias de la Mama , Relaciones Médico-Paciente , Femenino , Humanos , Neoplasias de la Mama/diagnóstico , Oncología Médica/educación , Encuestas y Cuestionarios , Comunicación
12.
Clinics (Sao Paulo) ; 79: 100327, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38330788

RESUMEN

AIM: miR-141-5p expression in patients with Early Spontaneous Abortion (ESA) and its correlation with hormone levels during pregnancy were investigated. METHODS: A total of 70 pregnant women with ESA were selected as the research group, and 70 normal pregnant women who chose abortion for non-medical reasons were selected as the Con group. Serum ß-HCG, Progesterone (P), and Estrogen (E2) were detected by enzyme-linked immunosorbent assay. Differentially expressed miRNAs were screened by miRNA microarray analysis. miR-141-5p expression was detected by RT-qPCR, and its correlation with serum ß-HCG, P, and E2 levels was analyzed. The diagnostic value of miR-141-5p for ESA was evaluated by the ROC curve. RESULTS: Serum ß-HCG, P, and E2 were decreased and serum miR-141-5p was increased in patients with ESA. Pearson correlation analysis showed that serum ß-HCG, P, and E2 levels were negatively correlated with miR-141-5p expression levels. ROC curve showed that miR-141-5p had a diagnostic value for ESA. CONCLUSIONS: miR-141-5p is related to hormone levels during pregnancy and is expected to become a new candidate diagnostic marker for ESA.


Asunto(s)
Aborto Espontáneo , MicroARNs , Humanos , Femenino , Embarazo , Aborto Espontáneo/diagnóstico , Relevancia Clínica , MicroARNs/genética , Biomarcadores , Progesterona
13.
Adv Mater ; 36(4): e2305818, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37657773

RESUMEN

Lithium-sulfur (Li-S) batteries stand out for their high theoretical specific capacity and cost-effectiveness. However, the practical implementation of Li-S batteries is hindered by issues such as the shuttle effect, tardy redox kinetics, and dendrite growth. Herein, an appealingly designed covalent organic framework (COF) with bi-functional active sites of cyanide groups and polysulfide chains (COF-CN-S) is developed as cooperative functional promoters to simultaneously address dendrites and shuttle effect issues. Combining in situ techniques and theoretical calculations, it can be demonstrated that the unique chemical architecture of COF-CN-S is capable of performing the following functions: 1) The COF-CN-S delivers significantly enhanced Li+ transport capability due to abundant ion-hopping sites (cyano-groups); 2) it functions as a selective ion sieve by regulating the dynamic behavior of polysulfide anions and Li+ , thus inhibiting shuttle effect and dendrite growth; 3) by acting as a redox mediator, the COF-CN-S can effectively control the electrochemical behavior of polysulfides and enhance their conversion kinetics. Based on the above advantages, the COF-CN-S endows Li-S batteries with excellent performance. This study highlights the significance of interface modification and offers novel insights into the rational design of organic materials in the Li-S realm.

14.
Radiographics ; 33(1): 213-28, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23322838

RESUMEN

Ductal carcinoma in situ (DCIS) is a noninvasive cancer that accounts for 25% of all breast cancers diagnosed in the United States. DCIS is a heterogeneous disease process with varied clinical manifestations and a broad spectrum of imaging findings. With advances in technology, the ability to detect early-stage cancers has improved, and understanding the role of ultrasonography (US) in the multimodality era of detection and diagnosis is paramount. When calcifications are identified at mammography, US can be performed to evaluate for an invasive component and to allow possible US-guided biopsy. Use of high-frequency transducers, spectral compounding, and speckle reduction algorithms can aid in the detection of calcifications. Calcified DCIS most commonly manifests as echogenic foci located within a mass or duct, associated with internal microlobulations, or distributed in a branch pattern. Noncalcified DCIS, which is more often identified in symptomatic patients, may manifest as a hypoechoic mass with microlobulated margins and no posterior acoustic features, or it may have a "pseudomicrocystic" appearance. Harmonic imaging and coronal reconstruction may improve detection of noncalcified DCIS. The appearance of DCIS at "second-look" US can be subtle and may warrant a lower threshold for detection, given a higher pretest probability of malignancy. US features are nonspecific, and careful correlation with respect to lesion location, size, shape, and depth is needed. The presence of internal vascularity can help increase the positive predictive value of US in this setting. US is a useful adjunct to mammography and magnetic resonance imaging, and recognizing the US appearance of DCIS will aid in the detection and diagnosis of this disease entity.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Carcinoma in Situ/diagnóstico por imagen , Carcinoma Ductal de Mama/diagnóstico por imagen , Ultrasonografía Mamaria , Algoritmos , Calcinosis/diagnóstico por imagen , Diagnóstico Diferencial , Femenino , Humanos , Interpretación de Imagen Asistida por Computador
15.
J Breast Imaging ; 5(5): 597-610, 2023 Sep 22.
Artículo en Inglés | MEDLINE | ID: mdl-38416912

RESUMEN

Breast MRI is a highly sensitive imaging modality that often detects findings that are occult on mammography and US. Given the overlap in appearance of benign and malignant lesions, an accurate method of tissue sampling for MRI-detected findings is essential. Although MRI-directed US and correlation with mammography can be helpful for some lesions, a correlate is not always found. MRI-guided biopsy is a safe and effective method of tissue sampling for findings seen only on MRI. The unique limitations of this technique, however, contribute to false negatives, which can result in delays in diagnosis and adverse patient outcomes; this is of particular importance as most MRI examinations are performed in the high-risk or preoperative setting. Here, we review strategies to minimize false negatives in biopsy of suspicious MRI findings, including appropriate selection of biopsy modality, use of meticulous MRI-guided biopsy technique, management after target nonvisualization, assessment of adequate lesion sampling, and determination of radiology-pathology concordance. A proposed management algorithm for MRI-guided biopsy results will also be discussed.


Asunto(s)
Mama , Biopsia Guiada por Imagen , Humanos , Biopsia Guiada por Imagen/métodos , Mama/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Mamografía , Examen Físico
16.
Clin Imaging ; 87: 56-60, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35504238

RESUMEN

The radiologists' role in axillary imaging in the setting of a suspicious breast mass is evolving in light of the Z0011 trial leading to expected practice variation. The purpose of our project was to generate a standardized algorithm guiding the utilization of axillary ultrasound in the setting of a highly suggestive or highly suspicious breast mass (BI-RADS 4C or 5) without a known cancer diagnosis. The algorithm was created with Z0011 practices in mind while reflecting the clinical preferences of our radiology and surgical teams. The four breast surgeons at our academic institution were individually queried regarding their preferred axillary imaging and biopsy approach. The best practices for axillary imaging were then developed in a breast imaging intradepartmental meeting. There was agreement among the surgical group that the presence of suspicious axillary lymph node (s) on ultrasound could be used for treatment planning and patient discussion but would not be used for surgical planning in most cases. They also agreed that an ultrasound-guided core needle biopsy of a suspicious axillary lymph node should be deferred until after surgical consultation. Discussion among our breast radiologists resulted in the consensus that axillary ultrasound in the setting of a BIRADS 4 or 5 mass should be deferred at its initial presentation unless there is palpable lymphadenopathy, suspicious lymph node on mammography, or a tumor is at least stage T3, presumably excluding them from Z0011 criteria. The decision was also made to defer biopsies of suspicious axillary lymph nodes without prior surgical consultation/discussion.


Asunto(s)
Neoplasias de la Mama , Biopsia del Ganglio Linfático Centinela , Axila/patología , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/patología , Femenino , Humanos , Escisión del Ganglio Linfático , Ganglios Linfáticos/diagnóstico por imagen , Ganglios Linfáticos/patología , Metástasis Linfática/diagnóstico por imagen , Metástasis Linfática/patología , Estadificación de Neoplasias , Estudios Retrospectivos , Biopsia del Ganglio Linfático Centinela/métodos , Ultrasonografía/métodos
17.
Radiol Clin North Am ; 59(1): 67-83, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33223001

RESUMEN

The sensitivity of mammography is more limited in patients with dense breasts and some patients at higher risk for breast cancer. Patients with intermediate or high risk for breast cancer may begin screening earlier and benefit from supplemental screening techniques beyond standard 2-dimensional mammography. A patient's individual risk factors for developing breast cancer, their breast density, and the evidence supporting specific modalities for a given clinical scenario help to determine the need for supplemental screening and the modality chosen. Additional factors include the availability of supplemental screening techniques at an individual institution, cost, insurance coverage, and state-specific breast density legislation.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Medios de Contraste , Aumento de la Imagen/métodos , Imagen por Resonancia Magnética/métodos , Mamografía/métodos , Ultrasonografía Mamaria/métodos , Mama/diagnóstico por imagen , Detección Precoz del Cáncer , Femenino , Humanos , Riesgo
18.
J Breast Imaging ; 3(1): 44-56, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33543122

RESUMEN

OBJECTIVE: The A6702 multisite trial confirmed that apparent diffusion coefficient (ADC) measures can improve breast MRI accuracy and reduce unnecessary biopsies, but also found that technical issues rendered many lesions non-evaluable on diffusion-weighted imaging (DWI). This secondary analysis investigated factors affecting lesion evaluability and impact on diagnostic performance. METHODS: The A6702 protocol was IRB-approved at 10 institutions; participants provided informed consent. In total, 103 women with 142 MRI-detected breast lesions (BI-RADS assessment category 3, 4, or 5) completed the study. DWI was acquired at 1.5T and 3T using a four b-value, echo-planar imaging sequence. Scans were reviewed for multiple quality factors (artifacts, signal-to-noise, misregistration, and fat suppression); lesions were considered non-evaluable if there was low confidence in ADC measurement. Associations of lesion evaluability with imaging and lesion characteristics were determined. Areas under the receiver operating characteristic curves (AUCs) were compared using bootstrapping. RESULTS: Thirty percent (42/142) of lesions were non-evaluable on DWI; 23% (32/142) with image quality issues, 7% (10/142) with conspicuity and/or localization issues. Misregistration was the only factor associated with non-evaluability (P = 0.001). Smaller (≤10 mm) lesions were more commonly non-evaluable than larger lesions (p <0.03), though not significant after multiplicity correction. The AUC for differentiating benign and malignant lesions increased after excluding non-evaluable lesions, from 0.61 (95% CI: 0.50-0.71) to 0.75 (95% CI: 0.65-0.84). CONCLUSION: Image quality remains a technical challenge in breast DWI, particularly for smaller lesions. Protocol optimization and advanced acquisition and post-processing techniques would help to improve clinical utility.

19.
AJR Am J Roentgenol ; 193(3): 826-31, 2009 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-19696298

RESUMEN

OBJECTIVE: Computer-aided evaluation (CAE) programs for breast MRI provide automated lesion kinetic information. The CAE kinetic parameters that best predict malignancy have not been established. We compared three CAE kinetic features of suspicious breast MRI lesions to determine associations with benign or malignant outcomes. MATERIALS AND METHODS: From 1,532 MRI examinations, all suspicious breast lesions initially detected with MRI and having CAE kinetics and subsequent biopsy were identified. Three CAE variables were compared for benign and malignant lesions: initial phase peak enhancement (greatest percentage signal intensity increase on first contrast-enhanced sequence), delayed phase enhancement categorized by a single type of kinetics comprising the largest percentage of enhancement (washout, plateau, or persistent), and delayed phase enhancement categorized by single most suspicious type of kinetics (any washout > any plateau > any persistent). RESULTS: One hundred twenty-five lesions (42 malignant, 83 benign) comprised the analysis set. There were no significant differences in initial peak enhancement (p = 0.28) or delayed kinetics categorized by largest percentage enhancement types (p = 0.39) between benign and malignant lesions. There was a significant difference in delayed kinetics categorized by the most suspicious enhancement types (p = 0.005). Of lesions with washout as most suspicious (any washout), 45.7% were malignant compared with 20.0% with plateau and 13.3% with entirely persistent enhancement. CONCLUSION: Of CAE kinetics analyzed, only delayed enhancement categorized by most suspicious type was significantly different between benign and malignant lesions. This supports the American College of Radiology BI-RADS Breast MRI Lexicon recommendation to report the "worst looking" kinetic curve.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Medios de Contraste/farmacocinética , Gadolinio DTPA/farmacocinética , Interpretación de Imagen Asistida por Computador/métodos , Imagen por Resonancia Magnética/métodos , Biopsia , Neoplasias de la Mama/patología , Diagnóstico Diferencial , Femenino , Humanos , Cinética , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Retrospectivos
20.
Clin Imaging ; 54: 133-137, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30639524

RESUMEN

PURPOSE: Digital breast tomosynthesis (DBT) has been shown to increase conspicuity of some mammographic findings, particularly architectural distortion (AD). The purpose of this retrospective study was to determine the positive predictive value of AD on diagnostic DBT, and evaluate associations between AD characteristics and histopathologic outcomes. METHODS: This IRB-approved, HIPAA-compliant study included diagnostic DBT exams performed between 1/2014 and 12/2015 that demonstrated AD. Imaging characteristics of AD, corresponding ultrasound and MRI exams, and pathology results were reviewed. Fisher's exact tests and a two-tailed t-test were performed. RESULTS: Seventy-seven cases of AD were visualized in 68 patients (ages 36-78 years, mean 54 years). Core biopsy of 74 cases of AD yielded malignant pathology in 26/74 (35%) tissue samples. Among 48/74 (65%) non-malignant cases of AD, 25 demonstrated a high-risk lesion, including radial scar in 20, with no upgrades to malignancy among 20 high-risk lesions that underwent surgical excision. Among 23 non high-risk causes of benign AD, stromal fibrosis was most common, present in 12 biopsy specimens. Associations between imaging characteristics of AD on DBT and histopathologic outcome were not statistically significant (one-view visualization 3/13 malignant, 10/13 benign, P = 0.52; DBT-only finding 1/11 malignant, 10/11 benign, P = 0.09). Of 48 cases with an ultrasound correlate, 22/48 (46%) were malignant versus 4/26 (15%) cases without an ultrasound correlate (P = 0.01). CONCLUSIONS: AD on diagnostic DBT was malignant in over one-third of cases. The presence of an ultrasound correlate was associated with malignancy.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Mama/diagnóstico por imagen , Manejo de la Enfermedad , Mamografía/métodos , Intensificación de Imagen Radiográfica/métodos , Adulto , Anciano , Biopsia con Aguja Gruesa , Neoplasias de la Mama/terapia , Femenino , Humanos , Persona de Mediana Edad , Estudios Retrospectivos
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