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1.
J Minim Invasive Gynecol ; 25(7): 1300-1304, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29609034

RESUMO

Two women (29 and 35 years of age) presented with an abdominal wall mass in close proximity to a cesarean scar. The main complaints consisted of pain at the site of the mass with catamenial exacerbations. Clinical and imaging findings were consistent with abdominal wall endometriosis in both cases. First, hormonal treatment was started, which proved unsuccessful. Typically, at this point, the proposed treatment would be wide surgical excision. Alternatively, magnetic resonance imaging-guided high-intensity focused ultrasound treatment was offered with the goal to diminish pain complaints noninvasively. Upon treatment, both patients' complaints diminished although some cyclic pain persisted. Overall, these cases show that magnetic resonance imaging-guided high-intensity focused ultrasound can be used as a noninvasive treatment method to reduce complaints in patients with abdominal wall endometriosis.


Assuntos
Parede Abdominal/patologia , Cicatriz/cirurgia , Endometriose/cirurgia , Ablação por Ultrassom Focalizado de Alta Intensidade , Parede Abdominal/diagnóstico por imagem , Adulto , Cesárea , Cicatriz/diagnóstico por imagem , Cicatriz/patologia , Endometriose/diagnóstico por imagem , Endometriose/patologia , Feminino , Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Humanos , Imageamento por Ressonância Magnética , Resultado do Tratamento
2.
Int J Stroke ; 13(1): 24-34, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28920537

RESUMO

Background Case-fatality rates after aneurysmal subarachnoid hemorrhage have decreased over the past decades. However, many patients who survive an aneurysmal subarachnoid hemorrhage have long-term functional and cognitive impairments. Aims We sought to review all data on conventional brain MRI obtained in the chronic phase after aneurysmal subarachnoid hemorrhage to (1) analyze the proportion of patients with cerebral infarction or brain volume changes; (2) investigate baseline determinants predictive of MRI-detected damage; and (3) assess if brain damage is predictive of patient outcome. Summary of review All original data published between 1 January 2000 and 4 October 2017 was searched using the PUBMED, EMBASE, and Web of Science databases. Based on preset inclusion criteria, 15 from 5200 articles were included with a total of 996 aneurysmal subarachnoid hemorrhage patients. Quality assessment, risk of bias assessment, and level of evidence assessment were performed. The results according to aim, with levels of evidence, were: (1) 25 to 81% of aneurysmal subarachnoid hemorrhage patients show infarcts (strong); there is a higher ratio of cerebrospinal fluid-to-intracranial volume in patients compared to controls (strong); (2) there is a negative relation between age (moderate), DCI (low) and brain volume measurement outcomes; (3) lower brain parenchymal volume (strong) and the presence of infarcts or infarct volumes (moderate) are associated with a worse outcome. Conclusion Patients after aneurysmal subarachnoid hemorrhage may demonstrate brain infarcts and decreased brain parenchyma, which is related to worse outcome. Thereby, both brain infarcts and brain volume measurements could be used as outcome markers in pharmaceutical trials. Systematic Review Registration PROSPERO CRD42016040095.


Assuntos
Encéfalo/patologia , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/patologia , Hemorragia Subaracnóidea/diagnóstico por imagem , Hemorragia Subaracnóidea/patologia , Humanos , Aneurisma Intracraniano/complicações , Imageamento por Ressonância Magnética , Neuroimagem , Prognóstico , Fatores de Risco , Hemorragia Subaracnóidea/complicações
3.
NMR Biomed ; 30(2)2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28032377

RESUMO

In vivo water- and fat-suppressed 1 H magnetic resonance spectroscopy (MRS) and 31 P magnetic resonance adiabatic multi-echo spectroscopic imaging were performed at 7 T in duplicate in healthy fibroglandular breast tissue of a group of eight volunteers. The transverse relaxation times of 31 P metabolites were determined, and the reproducibility of 1 H and 31 P MRS was investigated. The transverse relaxation times for phosphoethanolamine (PE) and phosphocholine (PC) were fitted bi-exponentially, with an added short T2 component of 20 ms for adenosine monophosphate, resulting in values of 199 ± 8 and 239 ± 14 ms, respectively. The transverse relaxation time for glycerophosphocholine (GPC) was also fitted bi-exponentially, with an added short T2 component of 20 ms for glycerophosphatidylethanolamine, which resonates at a similar frequency, resulting in a value of 177 ± 6 ms. Transverse relaxation times for inorganic phosphate, γ-ATP and glycerophosphatidylcholine mobile phospholipid were fitted mono-exponentially, resulting in values of 180 ± 4, 19 ± 3 and 20 ± 4 ms, respectively. Coefficients of variation for the duplicate determinations of 1 H total choline (tChol) and the 31 P metabolites were calculated for the group of volunteers. The reproducibility of inorganic phosphate, the sum of phosphomonoesters and the sum of phosphodiesters with 31 P MRS imaging was superior to the reproducibility of 1 H MRS for tChol. 1 H and 31 P data were combined to calculate estimates of the absolute concentrations of PC, GPC and PE in healthy fibroglandular tissue, resulting in upper limits of 0.1, 0.1 and 0.2 mmol/kg of tissue, respectively.


Assuntos
Mama/metabolismo , Compostos de Fósforo/metabolismo , Fósforo/farmacocinética , Espectroscopia de Prótons por Ressonância Magnética/métodos , Adulto , Mama/anatomia & histologia , Feminino , Humanos , Taxa de Depuração Metabólica , Compostos Radiofarmacêuticos/farmacocinética , Valores de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Processamento de Sinais Assistido por Computador , Distribuição Tecidual
5.
Front Oncol ; 6: 29, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26913240

RESUMO

PURPOSE: The identification of the phosphodiester (PDE) (31)P MR signals in the healthy human breast at ultra-high field. METHODS: In vivo (31)P MRS measurements at 7 T of the PDE signals in the breast were performed investigating the chemical shifts, the transverse- and the longitudinal relaxation times. Chemical shifts and transverse relaxation times were compared with non-ambiguous PDE signals from the liver. RESULTS: The chemical shifts of the PDE signals are shifted -0.5 ppm with respect to glycerophosphocholine (GPC) and glycerophosphoethanolamine (GPE), and the transverse and longitudinal relaxation times for these signals are a factor 3 to 4 shorter than expected for aqueous GPC and GPE. CONCLUSION: The available experimental evidence suggests that GPC and GPE are not the main source of the PDE signals measured in fibroglandular breast tissue at 7 T. These signals may predominantly originate from mobile phospholipids.

6.
Springerplus ; 5: 13, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26759752

RESUMO

The aim of this study is to compare the current state of lesion identification, the BI-RADS classification and the contrast-enhancement behavior at 7T and 3T breast MRI in the same patient group. Twenty-seven patients with thirty suspicious lesions were selected for this prospective study and underwent both 7T and 3T MRI. All examinations were rated by two radiologists (R1 and R2) independently on image quality, lesion identification and BI-RADS classification. We assessed sensitivity, specificity, NPV and PPV, observer agreement, lesion sizes, and contrast-enhancement-to-noise ratios (CENRs) of mass lesions. Fifteen of seventeen histopathological proven malignant lesions were detected at both field strengths. Image quality of the dynamic series was good at 7T, and excellent at 3T (P = 0.001 for R1 and P = 0.88 for R2). R1 found higher rates of specificity, NPV and PPV at 7T when compared to 3T, while R2 found the same results for sensitivity, specificity, NPV and PPV for both field strengths. The observers showed excellent agreement for BI-RADS categories at 7T (κ = 0.86) and 3T (κ = 0.93). CENRs were higher at 7T (P = 0.015). Lesion sizes were bigger at 7T according to R2 (P = 0.039). Our comparison study shows that 7T MRI allows BI-RADS conform analysis. Technical improvements, such as acquisition of T2w sequences and adjustment of B1+ field inhomogeneity, are still necessary to allow clinical use of 7T breast MRI.

7.
World J Clin Oncol ; 5(2): 61-70, 2014 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-24829852

RESUMO

Early detection and diagnosis of breast cancer are essential for successful treatment. Currently mammography and ultrasound are the basic imaging techniques for the detection and localization of breast tumors. The low sensitivity and specificity of these imaging tools resulted in a demand for new imaging modalities and breast magnetic resonance imaging (MRI) has become increasingly important in the detection and delineation of breast cancer in daily practice. However, the clinical benefits of the use of pre-operative MRI in women with newly diagnosed breast cancer is still a matter of debate. The main additional diagnostic value of MRI relies on specific situations such as detecting multifocal, multicentric or contralateral disease unrecognized on conventional assessment (particularly in patients diagnosed with invasive lobular carcinoma), assessing the response to neoadjuvant chemotherapy, detection of cancer in dense breast tissue, recognition of an occult primary breast cancer in patients presenting with cancer metastasis in axillary lymph nodes, among others. Nevertheless, the development of new MRI technologies such as diffusion-weighted imaging, proton spectroscopy and higher field strength 7.0 T imaging offer a new perspective in providing additional information in breast abnormalities. We conducted an expert literature review on the value of breast MRI in diagnosing and staging breast cancer, as well as the future potentials of new MRI technologies.

8.
NMR Biomed ; 27(5): 539-46, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24535752

RESUMO

The aim of this study was to detect microcalcifications in human whole breast specimens using high-field MRI. Four mastectomy specimens, obtained with approval of the institutional review board, were subjected to gradient-echo MRI acquisitions on a high-field MR scanner. The phase derivative was used to detect microcalcifications. The echo time and imaging resolution were varied to study the sensitivity of the proposed method. Computed tomography images of the mastectomy specimens and prior acquired mammography images were used to validate the results. A template matching algorithm was designed to detect microcalcifications automatically. The three spatial derivatives of the signal phase surrounding a field-perturbing object allowed three-dimensional localization, as well as the discrimination of diamagnetic field-perturbing objects, such as calcifications, and paramagnetic field-perturbing structures, e.g. blood. A longer echo time enabled smaller disturbances to be detected, but also resulted in shading as a result of other field-disturbing materials. A higher imaging resolution increased the detection sensitivity. Microcalcifications in a linear branching configuration that spanned over 8 mm in length were detected. After manual correction, the automatic detection tool identified up to 18 microcalcifications within the samples, which was in close agreement with the number of microcalcifications found on previously acquired in vivo mammography images. Microcalcifications can be detected by MRI in human whole breast specimens by the application of phase derivative imaging.


Assuntos
Mama/patologia , Calcinose/diagnóstico , Calcinose/patologia , Imageamento por Ressonância Magnética , Automação , Mama/cirurgia , Calcinose/cirurgia , Simulação por Computador , Feminino , Humanos , Mastectomia
9.
Springerplus ; 3: 634, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25932360

RESUMO

Here we investigate the feasibility of tumor metabolism monitoring in T1c to T3 breast cancer during neoadjuvant chemotherapy by means of phosphorus ((31)P) magnetic resonance spectroscopy at 7 tesla (T). Five breast cancer patients were examined using a (31)P MRSI sequence, prior to-, halfway-, and after neoadjuvant chemotherapy. The (31)P MRSI data were analyzed on group and individual level and compared to a spectrum of a group of healthy volunteers. Ratios of phosphomonoesters (PME) to phosphodiesters (PDE) and phosphomonoesters to inorganic phosphate (Pi) were determined. Histopathologic assessment showed four partial responders and one complete responder to chemotherapy. The (31)P spectrum of the patient group was distinctly different from the (31)P spectrum of healthy volunteers and transformed its shape during the course of chemotherapy towards the shape of the spectrum of the healthy volunteers. Prior to chemotherapy the PME to PDE signal ratio and the PME to Pi signal ratio were high, and during the course of the chemotherapy these ratios normalized to the value of the healthy volunteers. Metabolite T 2 values in tumor tissue tended to be lower than those for healthy glandular tissue. Assessment of individual patients showed that four out of five had a significant drop of the PME to Pi ratio by a factor of 2 or more. On average, the pH of the tumor, calculated from chemical shift variation of Pi, was 0.19 units lower before chemotherapy. We have demonstrated that the sensitivity of (31)P MRSI in breast cancer at 7 T is sufficient to detect alterations in membrane metabolism during neoadjuvant chemotherapy, which may be used for early assessment of treatment efficacy.

10.
Eur Radiol ; 23(11): 2961-8, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23982289

RESUMO

OBJECTIVE: To assess the feasibility of 7-T contrast-enhanced breast MRI in patients with suspicious masses. METHODS: Twenty patients with 23 suspicious breast masses on conventional imaging (mean size 13 mm, range 5-27 mm) were examined at 7 T. The MRI protocol included a dynamic series with injection of 0.1 mmol/kg gadobutrol (seven consecutive 3D T1-weighted gradient echo sequences, resolution 1 × 1 × 2 mm(3), temporal resolution 63 s) and ultra-high-resolution imaging (T1-weighted 3D gradient echo sequence, resolution 0.45 × 0.57 × 0.45 mm(3)). Two observers (R1 and R2) independently judged the examinations on image quality and classified lesions according to BI-RADS. The added value of ultra-high-resolution imaging was assessed. RESULTS: The image quality was deemed excellent in 1 and 0, good in 10 and 12, sufficient in 8 and 8, and insufficient in 1 and 0 for R1 and R2 respectively. Twenty of the 23 lesions were identified at 7-T MRI by both observers. All histopathologically proven malignant lesions (n = 19) were identified and classified as BI-RADS-MRI 4 or 5. Ultra-high-resolution imaging increased reader confidence in 88 % (R1) and 59 % (R2) of acquisitions. CONCLUSION: The study shows the feasibility of dynamic contrast-enhanced 7-T breast MRI, where all malignant mass lesions were identified by two observers. KEY POINTS: • Magnetic resonance imaging is important in the evaluation of breast cancer. • Recently, 7-T MRI has become available. • The 7-T dynamic contrast-enhanced breast MRI is feasible in patients. • The 7-T breast examinations are amenable to evaluation according to BI-RADS.


Assuntos
Neoplasias da Mama/diagnóstico , Mama/patologia , Meios de Contraste , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética/métodos , Compostos Organometálicos , Adulto , Idoso , Diagnóstico Diferencial , Estudos de Viabilidade , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes
11.
Magn Reson Imaging ; 31(4): 613-7, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23116848

RESUMO

PURPOSE: Here we describe our first experience with contrast-enhanced (CE) MRI of breast cancer at 7 tesla (T), compared to 3T and histopathology. MATERIALS AND METHODS: A 52 year old female patient with a mammographically suspicious breast mass (BI-RADS V) underwent 7 T CE-MRI. Results were described according to the BI-RADS-MRI criteria and compared to 3T and histopathology. RESULTS: After contrast administration, a homogeneously enhancing, irregular spiculated mass was depicted at both 3T and 7 T; sizes were identical. The most malignant kinetic curve was characterized by a rapid initial rise followed by a wash-out pattern in the delayed phase, i.e. a type 3 curve, at both field strengths. Even though T1-effects of contrast agents are suggested to be reduced at higher fields, quantification of contrast enhancement-to-noise ratio showed a ratio of 4.6 at 7 T and 2.8 at 3T when comparing contrast-to-noise of the mass before and after contrast administration. Both examinations, using a single dose of gadolinium-based contrast agent, achieved good image quality. Final histopathological evaluation showed an invasive ductulolobular carcinoma with an intraductal component. CONCLUSION: This initial experience suggests that clinical contrast-enhanced 7 T MRI of the breast is technically feasible and may allow BI-RADS-conform analysis.


Assuntos
Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Carcinoma Lobular/patologia , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Feminino , Humanos , Pessoa de Meia-Idade , Invasividade Neoplásica , Projetos Piloto , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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