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1.
J Magn Reson Imaging ; 2019 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-31343790

RESUMO

Advances in both imaging and computers have led to the rise in the potential use of artificial intelligence (AI) in various tasks in breast imaging, going beyond the current use in computer-aided detection to include diagnosis, prognosis, response to therapy, and risk assessment. The automated capabilities of AI offer the potential to enhance the diagnostic expertise of clinicians, including accurate demarcation of tumor volume, extraction of characteristic cancer phenotypes, translation of tumoral phenotype features to clinical genotype implications, and risk prediction. The combination of image-specific findings with the underlying genomic, pathologic, and clinical features is becoming of increasing value in breast cancer. The concurrent emergence of newer imaging techniques has provided radiologists with greater diagnostic tools and image datasets to analyze and interpret. Integrating an AI-based workflow within breast imaging enables the integration of multiple data streams into powerful multidisciplinary applications that may lead the path to personalized patient-specific medicine. In this article we describe the goals of AI in breast cancer imaging, in particular MRI, and review the literature as it relates to the current application, potential, and limitations in breast cancer. Level of Evidence: 3 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2019.

2.
Br J Radiol ; : 20190302, 2019 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-31271535

RESUMO

OBJECTIVES: To compare a low-dose dynamic contrast-enhanced breast MRI protocol (LITE MRI) to standard-dosage using a dual-dose injection technique. METHODS: 8 females with a total of 10 lesions with imaging features compatible with fibroadenoma were imaged using a dual-dose dynamic contrast-enhanced-MRI (DCE-MRI) technique. After pre-contrast scans, 15% of a standard dose of contrast was administered; approximately 10 min later, the remaining 85% of the standard dose was administered. Enhancement kinetic parameters, conspicuity and signal-to-noise ratio were measured quantitatively. RESULTS: One lesion showed no enhancement in either DCE series. All nine of the enhancing lesions were visualized in both the low-dose and standard-dose images. While the (low-to-standard) ratio of contrast doses was roughly 0.18, this did not match the ratios of kinetic parameters. Lesion conspicuity and enhancement rate were both higher in the low-dose images, with (low-to-standard) ratios 1.5 ± 0.1 and 1.2 ± 0.4, respectively. The upper limit of enhancement (ratio 0.3 ± 0.1) and signal-to-noise ratio (ratio 0.5 ± 0.1) were higher in the standard-dose images, but less than expected based on the ratio of the doses. CONCLUSIONS: This preliminary study demonstrates that LITE MRI has the potential to match standard DCE-MRI in the detection of enhancing lesions. Additionally, LITE MRI may enhance sensitivity to contrast media dynamics. ADVANCES IN KNOWLEDGE: Lower doses of MRI contrast media may be equally effective in the detection of breast lesions, and increase sensitivity to contrast media dynamics. LITE MRI may help increase screening compliance and long-term patient safety.

3.
Radiology ; 291(1): 15-20, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30747591

RESUMO

Background Previous studies have suggested that breast parenchymal texture features may reflect the biologic risk factors associated with breast cancer development. Therefore, combining the characteristics of normal parenchyma from the contralateral breast with radiomic features of breast tumors may improve the accuracy of digital mammography in the diagnosis of breast cancer. Purpose To determine whether the addition of radiomic analysis of contralateral breast parenchyma to the characterization of breast lesions with digital mammography improves lesion classification over that with radiomic tumor features alone. Materials and Methods This HIPAA-compliant, retrospective study included 182 patients (age range, 25-90 years; mean age, 55.9 years ± 14.9) who underwent mammography between June 2002 and July 2009. There were 106 malignant and 76 benign lesions. Automatic lesion segmentation and radiomic analysis were performed for each breast lesion. Radiomic texture analysis was applied in the normal regions of interest in the contralateral breast parenchyma to assess the mammographic parenchymal patterns. The classification performance of both individual features and the output from a Bayesian artificial neural network classifier was evaluated with the leave-one-patient-out method by using the area under the receiver operating characteristic curve (AUC) as the figure of merit in the task of differentiating between malignant and benign lesions. Results The performance of the combined lesion and parenchyma classifier in the differentiation between malignant and benign mammographic lesions was better than that with the lesion features alone (AUC = 0.84 ± 0.03 vs 0.79 ± 0.03, respectively; P = .047). Overall, six radiomic features-spiculation, margin sharpness, size, circularity from the tumor feature set, and skewness and power law beta from the parenchymal feature set-were selected more than 50% of the time during the feature selection process on the combined feature set. Conclusion Combining quantitative radiomic data from tumors with contralateral parenchyma characterizations may improve diagnostic accuracy for breast cancer. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Shaffer in this issue.

4.
Eur Radiol ; 2018 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-30255252

RESUMO

OBJECTIVES: To evaluate the diagnostic utility of electric properties tomography (EPT) in differentiating benign from malignant breast lesions in comparison with dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). METHODS: In this institutional review board-approved retrospective study, 116 consecutive patients with 141 breast lesions (50 benign and 91 malignant) underwent 3-T MRI, including 3D turbo-spin echo (TSE) sequence and standard DCE-MRI scans between January 2014 and January 2017. The lesions were segmented semi-automatically using subtraction DCE-MR images, and they were registered to the phase images from 3D TSE. The mean conductivity of the lesion was obtained from phase-based reconstruction of lesions. From the DCE-MRI, initial enhancement rate (IER) and signal enhancement ratio (SER) were calculated from signal intensity (SI) as follows: IER = (SIearly - SIpre)/SIpre, SER = (SIearly - SIpre)/(SIdelayed - SIpre). The parameters from EPT and the DCE-MRI were compared between benign and malignant lesions. RESULTS: There was significant difference in mean conductivity (0.14 ± 1.77 vs 1.14 ± 1.36 S/m, p < 0.0001) and SER (0.77 ± 0.28 vs 1.04 ± 0.25, p < 0.0001) between benign and malignant lesions, but not in IER (p = 0.06). Receiver operating curve (ROC) analysis revealed that the area under the curve (AUC) of the mean conductivity and SER was 0.71 and 0.80, respectively, without significant difference (p = 0.15). CONCLUSIONS: The mean conductivity of EPT was significantly different between benign and malignant breast lesions as well as kinetic parameter or SER from DCE-MRI. KEY POINTS: • The conductivity of malignant lesions was higher than that of benign lesions. • EPT helps differentiatie benign from malignant lesions. • Diagnostic ability of EPT was not significantly different from that of DCE-MRI.

5.
Clin Cancer Res ; 2018 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-30154229

RESUMO

PURPOSE: To establish a cohort of high-risk women undergoing intensive surveillance for breast cancer. METHODS: We performed dynamic contrast-enhanced magnetic resonance imaging (MRI) every 6 months in conjunction with annual mammography (MG). Eligible participants had a cumulative lifetime breast cancer risk ≥ 20% and/or tested positive for a pathogenic mutation in a known breast cancer susceptibility gene. RESULTS: Between 2004-2016, we prospectively enrolled 295 women, including 157 mutation carriers (75 BRCA1, 61 BRCA2); participants' mean age at entry was 43.3 years. Seventeen cancers were later diagnosed: four ductal carcinoma in situ (DCIS) and thirteen early stage invasive breast cancers. Fifteen cancers occurred in mutation carriers (11 BRCA1, 3 BRCA2, 1 CDH1). Median size of the invasive cancers was 0.61 cm. No patients had lymph node metastasis at time of diagnosis and no interval invasive cancers occurred. The sensitivity of bi-annual MRI alone was 88.2% and annual MG plus bi-annual MRI was 94.1%. The cancer detection rate of bi-annual MRI alone was 0.7% per 100 screening episodes, which is similar to the cancer detection rate of 0.7% per 100 screening episodes for annual MG plus bi-annual MRI. The number of recalls and biopsies needed to detect one cancer by bi-annual MRI were 2.8 and 1.7 in BRCA1 carriers, 12.0 and 8.0 in BRCA2 carriers, and 11.7 and 5.0 in non-BRCA1/2 carriers, respectively. CONCLUSIONS: Bi-annual MRI performed well for early detection of invasive breast cancer in genomically stratified high-risk women. No benefit was associated with annual MG screening plus bi-annual MRI screening.

6.
Acad Radiol ; 2018 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-30076083

RESUMO

RATIONALE AND OBJECTIVES: With the growing adoption of digital breast tomosynthesis (DBT) in breast cancer screening, we compare the performance of deep learning computer-aided diagnosis on DBT images to that of conventional full-field digital mammography (FFDM). MATERIALS AND METHODS: In this study, we retrospectively collected FFDM and DBT images of 78 biopsy-proven lesions from 76 patients. A region of interest was selected for each lesion on FFDM, synthesized 2D, and DBT key slice images. Features were extracted from each lesion using a pretrained convolutional neural network (CNN) and served as input to a support vector machine classifier trained in the task of predicting likelihood of malignancy. RESULTS: From receiver operating characteristic (ROC) analysis of all 78 lesions, the synthesized 2D image performed best in both the cradiocaudal view (area under the ROC curve [AUC] = 0.81, SE = 0.05) and mediolateral oblique view (AUC = 0.88, SE = 0.04) in the task of lesion characterization. When cradiocaudal and mediolateral oblique data of each lesion were merged through soft voting, DBT key slice image performed best (AUC = 0.89, SE = 0.04). When only masses and architectural distortions (ARDs) were considered, DBT performed significantly better than FFDM (p = 0.024). CONCLUSION: DBT performed significantly better than FFDM in the merged view classification of mass and ARD lesions. The increased performance suggests that the information extracted by the CNN from DBT images may be more relevant to lesion malignancy status than the information extracted from FFDM images. Therefore, this study provides supporting evidence for the efficacy of computer-aided diagnosis on DBT in the evaluation of mass and ARD lesions.

7.
Clin Imaging ; 48: 69-73, 2018 Mar - Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29035756

RESUMO

PURPOSE: To evaluate whether the disease status of the pre-neoadjuvant chemotherapy (NAC) core biopsied lymph node (preNACBxLN) in patients with node positive breast cancer corresponds to nodal status of all surgically retrieved lymph nodes (LNs) post-NAC and whether wire localization of this LN is feasible. MATERIALS AND METHODS: HIPPA compliant IRB approved retrospective study including breast cancer patients (a.) with preNACBxLN confirmed metastases, (b.) who received NAC, and (c.) underwent wire localization of the preNACBxLN. Electronic medical records were reviewed. Fisher's exact test was used to compare differences in residual disease post-NAC among breast cancer subtypes. RESULTS: 28 women with node positive breast cancer underwent ultrasound guided wire localization of the preNACBxLN, without complication. There was no evidence of residual nodal disease for 16 patients, with mean 4.4 (median 4) LNs resected. 12 patients had residual nodal metastases, with mean 9.2 (median 7) LNs resected and mean 2.3 (median 2) LNs with tumor involvement. 11 patients had metastases detected within the localized LN. One patient had micrometastasis in a sentinel LN, despite no residual disease in the preNACBxLN. Patients with luminal A/B breast cancer more often had residual nodal metastases (86%) at pathology, as compared to patients with HER2+ (20%) and Triple Negative breast cancer (50%), though not quite achieving statistical significance (p=0.055). CONCLUSION: Ultrasound guided wire localization of the preNACBxLN is feasible and may improve detection of residual tumor in patients post-NAC.


Assuntos
Neoplasias da Mama/patologia , Linfonodos/patologia , Biópsia de Linfonodo Sentinela/métodos , Ultrassonografia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Axila/patologia , Neoplasias da Mama/tratamento farmacológico , Estudos de Viabilidade , Feminino , Humanos , Metástase Linfática/diagnóstico , Pessoa de Meia-Idade , Terapia Neoadjuvante , Estudos Retrospectivos
8.
Top Magn Reson Imaging ; 26(5): 183-189, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28961567

RESUMO

Although published studies have revealed that magnetic resonance imaging (MRI) is by far the most effective imaging modality for cancer detection, it is currently considered cost-ineffective for screening women at an intermediate risk for breast cancer. The concept of an "abbreviated MRI" protocol has recently emerged as a possible solution for reducing the cost of MRI. The abbreviated MRI is a shortened version of the standard MRI, consisting of a single early phase dynamic contrast enhanced (DCE) series. Several clinical studies have shown that this MRI protocol would not affect sensitivity or specificity for breast MRI screening purposes. In clinical practice, morphologic evaluation and kinetic assessment are 2 major components of the interpretation process. However, kinetic assessment cannot be performed with the abbreviated protocol, because multiple sets of post-contrast images are necessary for the generation of kinetic curves. "Accelerated MRI" is a collective term for imaging techniques that acquire DCE-MR images in a very short time. Published studies suggest that the kinetic assessment during the very early post-contrast phase obtained with the accelerated MRI techniques is comparable to that with the standard MRI techniques. Applying accelerated MR techniques could potentially enhance the abbreviated MRI protocol in terms of diagnostic potential, while maintaining the shorter study time. Thus, the abbreviated MRI protocol associated with accelerated MRI techniques may provide value for screening and for diagnostic purposes.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Imagem por Ressonância Magnética/métodos , Meios de Contraste , Feminino , Humanos , Sensibilidade e Especificidade
9.
J Magn Reson Imaging ; 46(6): 1738-1747, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28295791

RESUMO

PURPOSE: To evaluate the diagnostic value of dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) for patients with atypical ductal hyperplasia (ADH) in predicting malignant upgrade. MATERIALS AND METHODS: 3T DCE-MRI was performed for 17 patients with ADH (median age 52, range 42-76) proven by stereotactic biopsy (n = 15), and ultrasound-guided biopsy (n = 2) from January 2011 to April 2015. All patients underwent surgical excision after the MRI. Two radiologists prospectively reviewed the MRI to determine the presence or absence of suspicious findings at the site of biopsy, and evaluated the MR features of any lesion present according to the Breast Imaging Reporting and Data System (BI-RADS) lexicon. MRI findings and clinical information were correlated with the final surgical pathology by multivariate analysis. RESULTS: Nine of 17 lesions were upgraded to malignancy. MRI demonstrated suspicious nonmass enhancement (NME) at the site of biopsy in all upgraded patients. The median size was 19.5 mm (range, 9-44 mm). In the eight patients without upgrade, no enhancement (n = 2), linear enhancement along the biopsy track (n = 4), thin rim enhancement around hematoma (n = 1), and a focal NME (n = 1) were seen. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of MRI findings were 100, 87.5, 90, and 100%, respectively. Multivariate analysis revealed that the presence of suspicious enhancement on MRI was the most significant predictor of upgrade to malignancy (P = 0.0006) CONCLUSION: Our study revealed a high NPV of DCE-MRI for patients with ADH in terms of malignant upgrade at subsequent surgery. This suggests that patients with ADH without suspicious enhancement on DCE-MRI might be followed with DCE-MRI rather than undergoing surgical excision. LEVEL OF EVIDENCE: 1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2017;46:1738-1747.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Carcinoma Intraductal não Infiltrante/diagnóstico por imagem , Carcinoma Intraductal não Infiltrante/patologia , Imagem por Ressonância Magnética/métodos , Mamografia/métodos , Adulto , Idoso , Biópsia , Mama , Meios de Contraste , Feminino , Humanos , Aumento da Imagem/métodos , Pessoa de Meia-Idade , Estudos Prospectivos , Sensibilidade e Especificidade
10.
J Magn Reson Imaging ; 46(5): 1341-1348, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28263425

RESUMO

PURPOSE: To develop and assess a full-coverage, sensitivity encoding (SENSE)-accelerated breast high spatial and spectral resolution (HiSS) magnetic resonance imaging (MRI) within clinically reasonable times as a potential nonenhanced MRI protocol for breast density measurement or breast cancer screening. MATERIALS AND METHODS: Sixteen women with biopsy-proven cancer or suspicious lesions, and 13 women who were healthy volunteers or were screened for breast cancer, received 3T breast MRI exams, including SENSE-accelerated HiSS MRI, which was implemented as a submillimeter spatial resolution echo-planar spectroscopic imaging (EPSI) sequence. In postprocessing, fat and water resonance peak height and integral images were generated from EPSI data. The postprocessing software was custom-designed, and new algorithms were developed to enable processing of whole-coverage axial HiSS datasets. Water peak height HiSS images were compared to pre- and postcontrast T1 -weighted images. Fat suppression was quantified as parenchymal-to-suppressed-fat signal ratio in HiSS water peak height and nonenhanced T1 -weighted images, and artifact levels were scored. RESULTS: Approximately a 4-fold decrease in acquisition speed, with a concurrent 2.5-fold decrease in voxel size, was achieved, with low artifact levels, and with spectral signal-to-noise ratio (SNR) of 45:1. Fat suppression was 1.9 times more effective (P < 0.001) in HiSS images than in T1 -weighted images (SPAIR), and HiSS images showed higher SNR in the axilla. HiSS MRI visualized 10 of 13 malignant lesions identified on dynamic contrast-enhanced (DCE)-MRI, and did not require skin removal in postprocessing to generate maximum intensity projection images. CONCLUSION: We demonstrate full-coverage, SENSE-accelerated breast HiSS MRI within clinically reasonable times, as a potential protocol for breast density measurement or breast cancer screening. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2017;46:1341-1348.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Mama/diagnóstico por imagem , Processamento de Imagem Assistida por Computador , Imagem por Ressonância Magnética , Adulto , Algoritmos , Biópsia , Densidade da Mama , Meios de Contraste , Imagem Ecoplanar , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Razão Sinal-Ruído , Software
12.
Semin Intervent Radiol ; 29(3): 155-60, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23997406

RESUMO

Hemoptysis represents a significant clinical entity with high morbidity and potential mortality. Most hemorrhages from a bronchial source arise in the setting of chronic inflammatory diseases. Medical management (in terms of resuscitation and bronchoscopic interventions) and surgery have severe limitations in these patient populations. Embolization procedures represent the first-line treatment for hemoptysis arising from a bronchial arterial source. This article discusses anatomical and technical considerations, as well as outcomes and complications, in the setting of bronchial arterial embolization in the treatment of hemoptysis.

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