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1.
Acta Radiol ; 65(7): 716-723, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38872362

RESUMO

BACKGROUND: With rising breast augmentations worldwide, there is an increasing clinical need for an early and accurate detection of implant complications. PURPOSE: To compare the quality of chemical shift encoding-based (CSE) water-fat-silicone separation compared to double inversion recovery (DIR) silicone-only imaging in breast magnetic resonance imaging (MRI). MATERIAL AND METHODS: This retrospective, single-center study included women with silicone implants subjected to 3-T MRI between January 2021 and March 2022. MRI included (i) two-dimensional silicone-only T2-weighted turbo spin echo DIR acquisition and (ii) three-dimensional CSE imaging based on multi-echo gradient-echo sequence enabling water-, fat-, and silicone-image separation. Images were evaluated and compared by three independent radiologists using a clinically established rating including differentiability of the silicone implant, visibility and contouring of the adjacent fibrous capsule, and accuracy of intralesional folds in a ranking of 1-5. The apparent contrast-to-noise (aCNR) was calculated. RESULTS: In 71 women, the average quality of water-fat-silicone images from CSE imaging was assessed as "good" (assessment 4 ± 0.9). In 68 (96%) patients, CSE imaging achieved a concise delineation of the silicone implant and precise visualization of the fibrous capsule that was not distinguishable in DIR imaging. Implant ruptures were more easily detected in CSE imaging. The aCNR was higher in CSE compared to DIR imaging (18.43 ± 9.8 vs. 14.73 ± 2.5; P = 0.002). CONCLUSION: Intrinsically co-registered water-fat-silicone-separated CSE-based images enable a reliable assessment of silicone implants. The simultaneously improved differentiability of the implant and fibrous capsule may provide clinicians with a valuable tool for an accurate evaluation of implant integrity and early detection of potential complications.


Assuntos
Implantes de Mama , Imageamento por Ressonância Magnética , Silicones , Humanos , Feminino , Estudos Retrospectivos , Imageamento por Ressonância Magnética/métodos , Adulto , Pessoa de Meia-Idade , Mama/diagnóstico por imagem , Água , Tecido Adiposo/diagnóstico por imagem , Géis de Silicone , Idoso
2.
Aesthet Surg J ; 41(11): NP1486-NP1495, 2021 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-34096996

RESUMO

BACKGROUND: Breast parenchyma interacts dynamically with an inserted implant, which may lead to local atrophy and sensory involvement, changes in vascular tissue and lactation, and volume reduction over time. The inversely proportional relationship between pressure and volume cannot be stated with certainty; that is, the larger implants having more local pressure would lead to compression, thus leading to atrophy of parenchyma more intensely compared with smaller implants. The objective of this study was to assess and list breast parenchyma volume changes with different pressure levels due to silicone implants of several sizes. OBJECTIVES: The authors sought to list the pressure exerted by silicone implants and the atrophy caused in the breast tissue. METHODS: Thirty-six women were placed in 3 groups (n = 12) and subjected to augmentation mammoplasty in the subglandular plane. The measurement of pressure in millimeters of mercury was conducted with help of molds with the same base and projection of implants introduced posteriorly. MRI was conducted in all participants in the preoperative period and at 6 and 12 months after surgery. RESULTS: Twelve months after breast implant insertion, the groups had a significant glandular volume reduction (mean, 12.97% in the right breast and 12.42% in the left breast). There was a statistically significant difference in the proportions of volume reduction and the pressure levels measured. CONCLUSIONS: A reduction in breast volume was verified. This reduction was also related to the level of pressure exerted on the implant.


Assuntos
Implante Mamário , Implantes de Mama , Mamoplastia , Atrofia , Mama/diagnóstico por imagem , Mama/cirurgia , Implantes de Mama/efeitos adversos , Feminino , Humanos , Mamoplastia/efeitos adversos , Géis de Silicone/efeitos adversos
3.
Eur Radiol ; 30(6): 3356-3362, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32060713

RESUMO

OBJECTIVES: Automated ultrasound of the breast has the advantage to have the whole breast scanned by technicians. Consequently, feedback to the radiologist about concurrent focal abnormalities (e.g., palpable lesions) is lost. To enable marking of patient- or physician-reported focal abnormalities, we aimed to develop skin markers that can be used without disturbing the interpretability of the image. METHODS: Disk-shaped markers were casted out of silicone. In this IRB-approved prospective study, 16 patients were included with a mean age of 57 (39-85). In all patients, the same volume was imaged twice using an automated breast ultrasound system, once with and once without a marker in place. Nine radiologists from two medical centers filled scoring forms regarding image quality, image interpretation, and confidence in providing a diagnosis based on the images. RESULTS: Marker adhesion was sufficient for automated scanning. Observer scores showed a significant shift in scores from excellent to good regarding diagnostic yield/image quality (χ2, 15.99, p < 0.01), and image noise (χ2, 21.20, p < 0.01) due to marker presence. In 93% of cases, the median score of observers "agree" with the statement that marker-induced noise did not influence image interpretability. Marker presence did not interfere with confidence in diagnosis (χ2, 6.00, p = 0.20). CONCLUSION: Inexpensive, easy producible skin markers can be used for accurate lesion marking in automated ultrasound examinations of the breast while image interpretability is preserved. Any marker-induced noise and decreased image quality did not affect confidence in providing a diagnosis. KEY POINTS: • The use of a skin marker enables the reporting radiologist to identify a location which a patient is concerned about. • The developed skin marker can be used for accurate breast lesion marking in ultrasound examinations.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Mama/diagnóstico por imagem , Imageamento Tridimensional/métodos , Silicones , Pele , Ultrassonografia Mamária/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Desenho de Equipamento , Equipamentos e Provisões , Feminino , Humanos , Pessoa de Meia-Idade , Projetos Piloto , Estudos Prospectivos , Sensibilidade e Especificidade
4.
Sensors (Basel) ; 20(4)2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32075006

RESUMO

Mechanical stages are routinely used to scan large expanses of biological specimens in photoacoustic imaging. This is primarily due to the limited field of view (FOV) provided by optical scanning. However, stage scanning becomes impractical at higher scanning speeds, or potentially unfeasible with heavier samples. Also, the slow scan-rate of the stages makes high resolution scanning a time-consuming process. Some clinical applications such as microsurgery require submicron resolution in a reflection-mode configuration necessitating a method that can acquire large field of views with a small raster scanning step size. In this study, we describe a method that combines mechanical stages with optical scanning for the rapid acquisition of high-resolution large FOVs. Optical scanning is used to acquire small frames in a two-dimensional grid formed by the mechanical stages. These frames are captured with specific overlap for effective image registration. Using a step size of 200 nm, we demonstrate mosaics of carbon fiber networks with FOVs of 0.8 × 0.8 mm2 captured in under 70 s with 1.2 µm image resolution. Larger mosaics yielding an imaging area of 3 × 3 mm2 are also shown. The method is validated by imaging a 1 × 1 mm2 section of unstained histopathological human tissue.


Assuntos
Técnicas Fotoacústicas , Tecnologia de Sensoriamento Remoto , Mama/diagnóstico por imagem , Fibra de Carbono/química , Feminino , Humanos , Imageamento Tridimensional , Processamento de Sinais Assistido por Computador , Fatores de Tempo
5.
Aesthet Surg J ; 37(3): 290-296, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28207033

RESUMO

Background: Clinical trials have demonstrated through core and independent studies that anatomical devices are safe and effective with low complication rates. The rotation rate of shaped breast implants in the literature is 0 to 8.2%. Currently there are no studies evaluating the efficacy of in office ultrasound or clinical rotation vs actual rotation rates seen on high-resolution ultrasound (HRUS). Objectives: The purpose of the study is to demonstrate the ease and reliability of HRUS for evaluating the rotation rate of 2 different brands of anatomic implants and to correlate this with the presumed clinical rate, as well as independent evaluators assessments. Methods: A total of 69 patients were followed up at routine intervals and were evaluated for rotation. Any implant rotated past >30° off of midline (outside 5-7 o'clock) was considered to be rotated. To determine if radiographic rotation was clinically evident, 20 composite patient photos were blindly evaluated. Results: A random total of 69 patients underwent bilateral augmentation mammoplasty with form stable anatimic gel implants using 138 implants. Twenty-nine of the 69 (42%) patients and 37 of the 138 (27%) implants were found to be rotated-using HRUS. Eight of the 69 (12%) patients had bilateral rotations. Independent evaluators were able to identify two of 12 (17%) possible rotations, or 2 rotations in 40 (5%) total implants. Conclusions: Anatomic form stable gel implants are actually rotated up to 25 times more frequently than previously thought, but these rotations do not translate into clinically significant sequela. High-resolution ultrasound is a simple alternative for breast implant surveillance and is better accepted by patients than magnetic resonance imaging (MRI). The clinical value of HRUS is also discussed and recommendations for FDA implant labeling changes are provided in this article. Level of Evidence: 4


Assuntos
Implante Mamário/instrumentação , Implantes de Mama , Mama/diagnóstico por imagem , Mama/cirurgia , Complicações Pós-Operatórias/diagnóstico por imagem , Géis de Silicone , Ultrassonografia Mamária/métodos , Adulto , Implante Mamário/efeitos adversos , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Imageamento Tridimensional , Pessoa de Meia-Idade , Fotografação , Complicações Pós-Operatórias/etiologia , Valor Preditivo dos Testes , Estudos Prospectivos , Desenho de Prótese , Rotação , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
6.
Aesthet Surg J ; 37(8): NP83-NP87, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-29036941

RESUMO

Breast implant-associated anaplastic large-cell lymphoma (BIA-ALCL) is a rare but serious complication in patients with breast implants, Patients are at risk of BIA-ALCL whether they receive breast implants for cosmetic reasons or for reconstructive purposes after surgery for breast cancer or prophylactic mastectomy. During the past decade, an increased number of reports have addressed BIA-ALCL. Herein, we describe BIA-ALCL in a transgender woman. The patient received breast implants as part of her gender transition and was diagnosed with BIA-ALCL 20 years later. The patient underwent several revisional operations in the 20 years after her primary breast surgery to treat unexplained pain with low-grade fever, severe capsular contracture (Baker grade III-IV), and several instances of implant rupture. In July 2016, the patient presented to our office with "late-onset" periprosthetic seroma 5 years after her last revisional breast surgery. She was diagnosed with BIA-ALCL without capsular invasion based on results of cytologic analysis of the periprosthetic seroma and histologic evaluation of the periprosthetic capsule. This diagnosis was verified further by results of immunohistochemical testing, which indicated expression of CD30 and T-cell markers in the periprosthetic seroma only. Our intentions with this case report are to demonstrate that all patients who undergo breast implantation, including transgender women, are at risk of BIA-ALCL and to highlight the importance of cytomorphologic and immunohistochemical screening of seroma fluid in patients with late-onset periprosthetic seroma. LEVEL OF EVIDENCE: 5.


Assuntos
Implante Mamário/efeitos adversos , Linfoma Anaplásico de Células Grandes/etiologia , Complicações Pós-Operatórias/etiologia , Falha de Prótese/efeitos adversos , Seroma/etiologia , Mama/diagnóstico por imagem , Mama/patologia , Mama/cirurgia , Implantes de Mama , Feminino , Humanos , Antígeno Ki-1/metabolismo , Linfoma Anaplásico de Células Grandes/diagnóstico por imagem , Linfoma Anaplásico de Células Grandes/patologia , Linfoma Anaplásico de Células Grandes/cirurgia , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Complicações Pós-Operatórias/cirurgia , Seroma/diagnóstico por imagem , Seroma/patologia , Seroma/cirurgia , Géis de Silicone/efeitos adversos , Fatores de Tempo , Pessoas Transgênero , Ultrassonografia
7.
Khirurgiia (Mosk) ; (9): 59-63, 2017.
Artigo em Russo | MEDLINE | ID: mdl-28914834

RESUMO

AIM: To improve the results of treatment of late inflammatory complications after injection contour plasty with polyacrylamide gel. MATERIAL AND METHODS: The authors analyze treatment of 21 patients with late septic complications of body contour plasty with polyacrylamide gel (PAGE) for the period 2010-2015. Mean age of women was 47.4 years. Time after primary intervention was 10-22 years. The depth of soft tissue lesion corresponded to II-III grade by D. Ahrenholz classification (1991), length - from 67 to 180 cm2. Mammary glands were the most common area of augmentation (18 cases). Besides antibiotic therapy and surgery complex treatment included exposure with plasma flows in various modes. RESULTS: Plasma technology significantly accelerated regenerative processes and provided stable microbial decontamination in 100% patients. High-energy vaporization was associated with maximum possible removal of PAGE from the tissues that was confirmed by histological examination.


Assuntos
Resinas Acrílicas , Antibacterianos/uso terapêutico , Coagulação com Plasma de Argônio/métodos , Reação a Corpo Estranho , Efeitos Adversos de Longa Duração , Mamoplastia , Mastectomia/métodos , Resinas Acrílicas/administração & dosagem , Resinas Acrílicas/efeitos adversos , Mama/diagnóstico por imagem , Terapia Combinada , Feminino , Reação a Corpo Estranho/diagnóstico , Reação a Corpo Estranho/etiologia , Reação a Corpo Estranho/fisiopatologia , Reação a Corpo Estranho/cirurgia , Géis/administração & dosagem , Géis/efeitos adversos , Humanos , Injeções , Efeitos Adversos de Longa Duração/diagnóstico , Efeitos Adversos de Longa Duração/etiologia , Efeitos Adversos de Longa Duração/fisiopatologia , Efeitos Adversos de Longa Duração/cirurgia , Mamoplastia/efeitos adversos , Mamoplastia/métodos , Pessoa de Meia-Idade , Federação Russa , Infecções dos Tecidos Moles/etiologia , Infecções dos Tecidos Moles/cirurgia , Resultado do Tratamento
8.
Magn Reson Med ; 75(5): 2064-2071, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26096754

RESUMO

PURPOSE: Evaluate the usefulness of diffusion-weighted spatiotemporally encoded (SPEN) methods to obtain apparent diffusion coefficient (ADC) maps of fibroglandular human breast tissue, in the presence of silicone implants. METHODS: Seven healthy volunteers with breast augmentation were scanned at 3 Tesla (T) using customized SPEN sequences yielding separate silicone and water (1) H images in one scan, together with their corresponding diffusion-weightings. RESULTS: SPEN's ability to deliver multiple spectrally resolved images in a single scan, coupled to the method's substantial robustness to magnetic field heterogeneities, served to acquire ADC maps that could be freed from contributions that did not belong to fibroglandular tissue. CONCLUSION: SPEN-based sequences incorporating spectral discrimination and diffusion-weighting enable the acquisition of reliable ADC maps despite the presence of dominant signals from silicone implants, thereby opening new screening possibilities for the identification of malignancies in breast augmented patients.


Assuntos
Mama/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , Silicones/química , Adulto , Artefatos , Mama/cirurgia , Implantes de Mama , Feminino , Voluntários Saudáveis , Humanos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Campos Magnéticos , Pessoa de Meia-Idade , Modelos Estatísticos , Imagens de Fantasmas , Próteses e Implantes , Água/química
11.
Ultrasound Med Biol ; 50(7): 1001-1009, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38575416

RESUMO

OBJECTIVE: We have studied the use of polymethyl methacrylate (PMMA) as an alternative biopsy marker that is readily detectable with ultrasound Doppler twinkling in cases of in vitro, ex vivo, or limited duration in vivo settings. This study investigates the long-term safety and ultrasound Doppler twinkling detectability of a PMMA breast biopsy marker following local perturbations and different dwell times in a 6-mo animal experiment. METHODS: This study, which was approved by our Institutional Animal Care and Use Committee, involved three pigs and utilized various markers, including PMMA (Zimmer Biomet), 3D-printed, and Tumark Q markers. Markers were implanted at different times for each pig. Mesh material or ethanol was used to induce a local inflammatory reaction near certain markers. A semiquantitative twinkling score assessed twinkling for actionable localization during monthly ultrasounds. At the primary endpoint, ultrasound-guided localization of lymph nodes with detectable markers was performed. Following surgical resection of the localized nodes, histomorphometric analysis was conducted to evaluate for tissue ingrowth and the formation of a tissue rind around the markers. RESULTS: No adverse events occurred. Twinkling scores of all markers for all three pigs decreased gradually over time. The Q marker exhibited the highest mean twinkling score followed by the PMMA marker, PMMA with mesh, and Q with ethanol. The 3D-printed marker with mesh and PMMA with ethanol had the lowest scores. All wire-localized lymph nodes were successfully resected. Despite varying percentages of tissue rind around the markers and a significant reduction in overall twinkling (p < 0.001) over time, mean PMMA twinkling scores remained clinically actionable at 6 and 5 mo using a General Electric C1-6 probe and 9L-probe, respectively. CONCLUSIONS: In this porcine model, the PMMA marker demonstrates an acceptable safety profile. Clinically actionable twinkling aids PMMA marker detection even after 6 mo of dwell time in porcine lymph nodes. The Q marker maintained the greatest twinkling over time compared to all the other markers studied.


Assuntos
Polimetil Metacrilato , Animais , Suínos , Feminino , Mama/diagnóstico por imagem , Ultrassonografia Mamária/métodos , Modelos Animais , Biópsia/métodos
12.
Int J Comput Assist Radiol Surg ; 19(1): 151-161, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37099215

RESUMO

PURPOSE: The WHO reported an increasing trend in the number of new cases of breast cancer, making it the most prevalent cancer in the world. This fact necessitates the availability of highly qualified ultrasonographers, which can be achieved by the widespread implementation of training phantoms. The goal of the present work is to develop and test an inexpensive, accessible, and reproducible technology for creating an anatomical breast phantom for practicing ultrasound diagnostic skills in grayscale and elastography imaging, as well as ultrasound-guided biopsy sampling. METHODS: We used FDM 3D printer and PLA plastic for printing an anatomical breast mold. We made a phantom using a mixture of polyvinyl chloride plastisol, graphite powder, and metallic glitter to simulate soft tissues and lesions. Various degrees of elasticity were imparted using plastisols of stiffness ranging from 3 to 17 on the Shore scale. The lesions were shaped by hand. The materials and methods used are easily accessible and reproducible. RESULTS: Using the proposed technology, we have developed and tested a basic, differential, and elastographic versions of the breast phantom. The three versions of the phantom are anatomical and intended for use in medical education: the basic version is for practicing primary hand-eye coordination skills; the differential one is for practicing the differential diagnosis skills; the elastographic version helps developing the skills needed for assessing the stiffness of tissues. CONCLUSION: The proposed technology allows the creation of breast phantoms for practicing hand-eye coordination and develop the critical skills for navigation and assessment of the shape, margins, and size of the lesion, as well as performing an ultrasound-guided biopsy. It is cost-effective, reproducible, and easily implementable, and could be instrumental in generating ultrasonographers with crucial skills for accurate diagnosis of breast cancer, especially in low-resource settings.


Assuntos
Neoplasias da Mama , Técnicas de Imagem por Elasticidade , Humanos , Feminino , Cloreto de Polivinila , Mama/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Técnicas de Imagem por Elasticidade/métodos , Imagens de Fantasmas , Elasticidade
14.
Asian Pac J Cancer Prev ; 24(3): 953-960, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36974550

RESUMO

BACKGROUND: The dose exposure associated with digital breast tomosynthesis (DBT) is evaluated by multiplying the mean glandular dose (MGD) of mammography (MMG) with the correction coefficient of the angle of X-ray incidence. However, it has been pointed out that there are various problems when using the MGD as a standard for risk assessment in breast cancer screening. Therefore, the aim of this study was to assess the breast-absorbed dose for different breast sizes for dose assessment. Furthermore, in this study, by measuring the dose distribution three-dimensionally, we aimed to examine the MGD correction method using the breast size as a factor. METHODS: A simulated breast phantom with a diameter of 40-160 mm and a total thickness of 40 mm, made with polymethyl methacrylate, was created by simulating the phantom shape used in the simulation calculation for calculating the MGD. It was made with polymethyl methacrylate. Radiochromic films were placed at different depths, which measured the breast-absorbed dose distribution three-dimensionally. The MGD was calculated from the breast-absorbed dose distribution obtained. RESULTS: The three-dimensional dose distribution revealed that there was a difference in the distribution of MMG and DBT with increasing depth. In addition, a lower X-ray energy and a smaller breast size resulted in a greater difference in the absorbed dose between DBT and MMG. CONCLUSION: Incorporating the DBT correction according to the breast size into the MGD improves the accuracy of dose evaluation by the MGD. Additionally, a corrected MGD provides useful information for risk assessment when DBT is used for breast cancer screening.


Assuntos
Neoplasias da Mama , Polimetil Metacrilato , Humanos , Feminino , Mama/diagnóstico por imagem , Mamografia/métodos , Neoplasias da Mama/diagnóstico por imagem , Simulação por Computador , Imagens de Fantasmas , Doses de Radiação
15.
Phys Med ; 98: 88-97, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35526373

RESUMO

PURPOSE: To design, fabricate and characterize 3D printed, anatomically realistic, compressed breast phantoms for digital mammography (DM) and digital breast tomosynthesis (DBT) x-ray imaging. MATERIALS: We realized 3D printed phantoms simulating healthy breasts, via fused deposition modeling (FDM), with a layer resolution of 0.1 mm and 100% infill density, using a dual extruder printer. The digital models were derived from a public dataset of segmented clinical breast computed tomography scans. Three physical phantoms were printed in polyethylene terephthalate (PET), acrylonitrile-butadiene-styrene (ABS), or in polylactic-acid (PLA) materials, using ABS as a substitute for adipose tissue, and PLA or PET filaments for replicating glandular and skin tissues. 3D printed phantoms were imaged at three clinical centers with DM and DBT scanners, using typical spectra. Anatomical noise of the manufactured phantoms was evaluated via the estimates of the ß parameter both in DM images and in images acquired via a clinical computed tomography (CT) scanner. RESULTS: DM and DBT phantom images showed an inner texture qualitatively similar to the images of a clinical DM or DBT exam, suitably reproducing the glandular structure of their computational phantoms. ß parameters evaluated in DM images of the manufactured phantoms ranged between 2.84 and 3.79; a lower ß was calculated from the CT scan. CONCLUSIONS: FDM 3D printed compressed breast phantoms have been fabricated using ABS, PLA and PET filaments. DM and DBT images with clinical x-ray spectra showed realistic textures. These phantoms appear promising for clinical applications in quality assurance, image quality and dosimetry assessments.


Assuntos
Mama , Mamografia , Mama/diagnóstico por imagem , Humanos , Mamografia/métodos , Imagens de Fantasmas , Poliésteres , Impressão Tridimensional , Raios X
16.
Phys Med Biol ; 67(24)2022 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-36541511

RESUMO

Objective. In this study, a novel voxel-by-voxel mixing method is presented, according to which two filaments of different material are combined during the three dimensional (3D) printing process.Approach. In our approach, two types of filaments were used for the replication of soft-tissues, a polylactic acid (PLA) filament and a polypropylene (PP) filament. A custom-made software was used, while a series of breast patient CT scan images were directly associated to the 3D printing process. Each phantom´s layer was printed twice, once with the PLA filament and a second time with the PP filament. For each material, the filament extrusion rate was controlled voxel-by-voxel and was based on the Hounsfield units (HU) of the imported CT images. The phantom was scanned at clinical CT, breast tomosynthesis and micro CT facilities, as the major processing was performed on data from the CT. A side by side comparison between patient´s and phantom´s CT slices by means of profile and histogram comparison was accomplished. Further, in case of profile comparison, the Pearson´s coefficients were calculated.Main results. The visual assessment of the distribution of the glandular tissue in the CT slices of the printed breast anatomy showed high degree of radiological similarity to the corresponding patient´s glandular distribution. The profile plots´ comparison showed that the HU of the replicated and original patient soft tissues match adequately. In overall, the Pearson´s coefficients were above 0.91, suggesting a close match of the CT images of the phantom with those of the patient. The overall HU were close in terms of HU ranges. The HU mean, median and standard deviation of the original and the phantom CT slices were -149, -167, ±65 and -121, -130, ±91, respectively.Significance. The results suggest that the proposed methodology is appropriate for manufacturing of anthropomorphic soft tissue phantoms for x-ray imaging and dosimetry purposes, since it may offer an accurate replication of these tissues.


Assuntos
Mama , Tomografia Computadorizada por Raios X , Humanos , Tomografia Computadorizada por Raios X/métodos , Mama/diagnóstico por imagem , Radiometria , Poliésteres , Imagens de Fantasmas , Impressão Tridimensional
17.
Clin Plast Surg ; 48(1): 59-69, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33220905

RESUMO

This article introduces the plastic surgeon to the basics of high-resolution ultrasound (HRUS) for screening breast implants. It describes how HRUS has become an accepted alternative to MRI for screening and diagnosis, and how plastic surgeons should use this new technology for the benefit of their patients and their practices. Basic principles, technology, and nomenclature are presented. Key steps to obtaining diagnostic images of breast implants are reviewed, including typical artifacts and sources of error. Imaging examples are presented. The article ends with a review and a step-by-step guide for plastic surgeons looking to use the technology.


Assuntos
Implantes de Mama , Mama/diagnóstico por imagem , Ultrassonografia Mamária/métodos , Feminino , Humanos , Sensibilidade e Especificidade , Géis de Silicone , Cirurgiões , Ultrassonografia Mamária/instrumentação
18.
Eur J Pharm Biopharm ; 158: 390-400, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33338603

RESUMO

Metastatic breast cancer is one of the most common causes of cancer-related death in women worldwide. The transmembrane metalloprotease-disintegrin (ADAM8) protein is highly overexpressed in triple-negative breast cancer (TNBC) cells and potentiates tumor cell invasion and extracellular matrix remodeling. Exploiting the high expression levels of ADAM8 in TNBC cells by delivering anti-ADAM8 antibodies efficiently to the targeted site can be a promising strategy for therapy of TNBC. For instance, a targeted approach with the aid of ultra-high field magnetic resonance imaging (UHF-MRI) activatable thermosensitive liposomes (LipTS-GD) could specifically increase the intracellular accumulation of cytotoxic drugs. The surface of doxorubicin-loaded LipTS-GD was modified by covalent coupling of MAB1031 antibody (LipTS-GD-MAB) in order to target the overexpressed ADAM8 in ADAM8 positive MDA-MB-231 cells. Physicochemical characterization of these liposomes was performed using size, surface morphology and UHF-MRI imaging analysis. In vitro cell targeting was investigated by the washing and circulation method. Intracellular trafficking and lysosomal colocalization were assessed by fluorescence microscopy. Cell viability, biocompatibility and in-ovo CAM assays were performed to determine the effectiveness and safety profiles of liposome formulations. Our results show specific binding and induction of doxorubicin release after LipTS-GD-MAB treatment caused a higher cytotoxic effect at the cellular target site.


Assuntos
Proteínas ADAM/metabolismo , Antibióticos Antineoplásicos/administração & dosagem , Anticorpos Monoclonais/farmacologia , Imagem por Ressonância Magnética Intervencionista , Proteínas de Membrana/metabolismo , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Animais , Antibióticos Antineoplásicos/farmacocinética , Disponibilidade Biológica , Mama/diagnóstico por imagem , Mama/patologia , Linhagem Celular Tumoral , Sobrevivência Celular , Embrião de Galinha , Membrana Corioalantoide , Doxorrubicina/administração & dosagem , Doxorrubicina/farmacocinética , Liberação Controlada de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Humanos , Lipossomos , Neoplasias de Mama Triplo Negativas/diagnóstico , Neoplasias de Mama Triplo Negativas/patologia
19.
PLoS One ; 15(6): e0235050, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32589678

RESUMO

OBJECTIVE: To evaluate the sensitivity (S) of BMRI to detect silicone gel bleeding in a prospective observational study, including consecutive patients referred for BMRI scan. METHODS: From January 2017 to March 2018, we evaluated patients with breast implants referred for BMRI in a prospective observational study. For SIGBIC diagnosis, we adopted three new original imaging features: black drop signal; T2* hyper signal mass; and delayed contrast enhancement, considered as irrevocable signs to detect gel bleeding (GB). Histology confirmed the presence of a silicone corpuscle in breast implant capsular specimens. The accuracy of BMRI SIGBIC findings to predict GB was determined. We also compared SIGBIC diagnosis criteria to those features proposed by the BI-RADS léxicon, considered as equivocal findings. RESULTS: 208 patients had SIGBIC diagnosis at BMRI, and the histology confirmed GB in all cases. There were no false-positive results. Compared to the BI-RADS equivocal findings (S = 0.74), SIGBIC criteria had better sensitivity for GB diagnosis. CONCLUSION: SIGBIC diagnosis has high sensitivity to predict GB by the three irrevocable BMRI features described by the authors. We suppose GB is underdiagnosed in clinical practice by BI-RADS features. TRIAL CERTIFICATION: Study protocol: Plataforma Brasil CAAE: 77215317.0.0000.0072.


Assuntos
Implantes de Mama/efeitos adversos , Mama , Granuloma de Corpo Estranho/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Géis de Silicone/efeitos adversos , Adulto , Idoso , Mama/diagnóstico por imagem , Mama/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Sensibilidade e Especificidade
20.
ACS Appl Mater Interfaces ; 12(5): 5456-5461, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31920072

RESUMO

Mesoporous silicon (PSi) nanoparticles have been widely studied in different biomedical imaging modalities due to their several beneficial material properties. However, they have not been found to be suitable for photoacoustic imaging due to their poor photothermal conversion performance. In the present study, biodegradable black mesoporous silicon (BPSi) nanoparticles with strong light absorbance were developed as superior image contrast agents for photoacoustic tomography (PAT), which was realized with a light-emitting diode (LED) instead of the commonly used laser. LED-based PAT offers the advantages of low cost, compactness, good mobility, and easy operation as compared to the traditional laser-based PAT modality. Nevertheless, the poor imaging sensitivity of the LED-PAT systems has been the main barrier to prevent their wide biomedical application because the LED light has low optical energy. The present study demonstrated that the imaging sensitivity of the LED-PAT system was significantly enhanced with the PEGylated BPSi (PEG-BPSi) nanoparticles. The PEG-BPSi nanoparticles were clearly detectable with a low concentration of 0.05 mg/mL in vitro and with an LED radiation energy of 5.2 µJ. The required concentration of the PEG-BPSi nanoparticles was 10 times lesser than that of the reference gold nanoparticles to reach the corresponding level of the imaging contrast. The ex vivo studies demonstrated that the submillimeter BPSi nanoparticle-based absorbers were distinguishable in chicken breast tissues. The strong contrast provided by the BPSi particles indicated that these particles can be utilized as novel contrast agents in PAT, especially in LED-based systems with low light intensity.


Assuntos
Meios de Contraste/química , Técnicas Fotoacústicas/métodos , Silício/química , Animais , Mama/diagnóstico por imagem , Galinhas , Ouro/química , Imageamento Tridimensional/métodos , Luz , Nanopartículas/química , Polietilenoglicóis/química , Porosidade
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