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1.
Eur Radiol ; 22(6): 1255-64, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22205445

RESUMO

OBJECTIVES: To evaluate whether magnetic resonance (MR) imaging features can predict the presence of occult invasion in cases of biopsy-proven pure ductal carcinoma in situ (DCIS). METHODS: We retrospectively reviewed 92 biopsy-proven pure DCIS in 92 women who underwent MR imaging. The following MR imaging findings were compared between confirmed DCIS and invasive breast cancer (IBC): lesion size, type, morphological and kinetic assessments by ACR BI-RADS MRI, and findings of fat-suppressed T2-weighted (FS-T2W) imaging. RESULTS: Sixty-eight of 92 (74%) were non-mass-like enhancements (NMLE) and 24 were mass lesions on MR imaging. Twenty-one of 68 (31%) NMLE and 13 of 24 (54%) mass lesions were confirmed as IBC. In NMLE lesions, large lesions (P = 0.007) and higher signal intensities (SI) on FS-T2W images (P = 0.032) were significantly associated with IBC. Lesion size remained a significant independent predictor of invasion in multivariate analysis (P = 0.032), and combined with FS-T2W SIs showed slightly higher observer performances (area under the curve, AUC, 0.71) than lesion size alone (AUC 0.68). There were no useful findings that enabled the differentiation of mass-type lesions. CONCLUSIONS: Breast MR imaging is potentially useful to predict the presence of occult invasion in biopsy-proven DCIS with NMLE. KEY POINTS: MR mammography permits more precise lesion assessment including ductal carcinoma in situ A correct diagnosis of occult invasion before treatment is important for clinicians This study showed the potential of MR mammography to diagnose occult invasion Treatment and/or aggressive biopsy can be given with greater confidence MR mammography can lead to more appropriate management of patients.


Assuntos
Biópsia por Agulha/estatística & dados numéricos , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/patologia , Carcinoma Ductal/epidemiologia , Carcinoma Ductal/patologia , Imageamento por Ressonância Magnética/estatística & dados numéricos , Adulto , Idoso , Neoplasias da Mama/cirurgia , Carcinoma Ductal/cirurgia , Feminino , Humanos , Incidência , Japão/epidemiologia , Pessoa de Meia-Idade , Invasividade Neoplásica , Cuidados Pré-Operatórios/estatística & dados numéricos , Prognóstico , Reprodutibilidade dos Testes , Medição de Risco , Fatores de Risco , Sensibilidade e Especificidade
2.
AJR Am J Roentgenol ; 198(6): W611-7, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22623579

RESUMO

OBJECTIVE: The purpose of this article is to determine the effectiveness of MRI for visualizing spiculated breast cancer lesions that were previously identified using mammography and to compare the diagnostic quality of 3- and 1.5-T dynamic MRI by assessing the visualization of spiculation in such lesions. MATERIALS AND METHODS: One hundred twenty MRI studies of breast cancers clearly identified as spiculated masses using mammography (71 MRI studies at 3 T that included both bilateral axial and unilateral sagittal images and 49 MRI studies at 1.5 T that included bilateral axial images only) were independently reviewed by three radiologists. The three different radiologists scored the visualization of the spiculation with respect to 3-T sagittal, 3-T axial, or 1.5-T axial images. RESULTS: The diagnostic quality of sagittal 3-T dynamic MRI studies, as determined by assessing the visualization of spiculation, was significantly better than that of axial 3-T (p = 0.009) and 1.5-T (p = 0.004) studies. For small (< 1 cm) lesions, the diagnostic quality of sagittal 3-T studies determined by assessing the visualization of spiculation was significantly better than that of axial 1.5-T studies (p = 0.029). CONCLUSION: Unilateral sagittal in-plane and through-plane high-spatial-resolution 3-T images can offer particularly higher spatial resolution for improved assessment of spiculation than do axial in-plane high-spatial-resolution images obtained at 1.5 and 3 T.


Assuntos
Neoplasias da Mama/patologia , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/diagnóstico por imagem , Distribuição de Qui-Quadrado , Meios de Contraste , Feminino , Gadolínio DTPA , Humanos , Mamografia , Pessoa de Meia-Idade , Estudos Prospectivos , Estatísticas não Paramétricas
3.
Breast Cancer ; 29(4): 677-687, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35220511

RESUMO

PURPOSE: To compare the diagnostic performances of contrast-enhanced digital mammography (CEDM) and breast MRI in evaluations of breast cancer, with a focus on the impact of background parenchymal enhancement (BPE) levels. METHODS: The present study included women who underwent CEDM and breast MRI to evaluate the disease extent of breast cancer between January 2018 and December 2019. Readers judged BPE levels (minimal-mild or moderate-marked) on CEDM, and were asked to assign findings suggesting malignancy using the following criteria: (1) enhancement other than BPE and (2) BI-RADS 4/5 calcifications without enhancement. On MRI, BI-RADS 3 and BI-RADS 4/5 lesions were evaluated as benign and malignant, respectively. The diagnostic performances of CEDM and MRI were compared separately between women with minimal-mild BPE and those with moderate-marked BPE. RESULTS: Sixty-nine patients comprising 43 postmenopausal and 26 premenopausal women were included in the present study. In total, 195 lesions (94 malignant and 101 benign) were identified. The sensitivity and specificity of CEDM for the diagnosis of all lesions were 90.8 and 91.5% with minimal-mild BPE and 79.3 and 76.2% with moderate-marked BPE, respectively. The sensitivity and specificity of MRI were 90.0% and 71.0% with minimal-mild BPE and 87.5% and 78.1% with moderate-marked BPE, respectively. The accuracy of CEDM was significantly superior to that of MRI in women with minimal-mild BPE on both CEDM and MRI (p = 0.002). Regarding the negative impact of a correct diagnosis on CEDM, the odds ratio of "moderate-marked BPE" was 0.382. CONCLUSION: In patients with minimal-mild BPE, the diagnostic performance of CEDM was superior to that of MRI.


Assuntos
Neoplasias da Mama , Mama/diagnóstico por imagem , Mama/patologia , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Meios de Contraste , Feminino , Humanos , Imageamento por Ressonância Magnética , Mamografia , Estudos Retrospectivos
4.
J Neurooncol ; 104(1): 239-45, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21110218

RESUMO

Skull metastases are malignant bone tumors which are increasing in incidence. The objectives of this study were to characterize the MR imaging features, locations, and extent of metastatic skull tumors to determine the frequency of the symptomatic disease, and to assess patient outcomes. Between September 2002 and March 2008, 175 patients undergoing routine head MR imaging were found to have metastatic skull tumors. Contrast-enhanced study with fat suppression was used in some cases when required. Classification of metastases was simplified to three yes/no questions: first, with regard to location (either in the calvarium or in the cranial base); second, with regard to distribution within the plane of the cranial bone (either "circumscribed" meaning clearly demarcated and confined to one bone, or "diffuse" and likely to spread across a suture to another bone); and third, with regard to invasion ("intraosseous" in cranial bones only, or "invasive" spreading from the skull, either out into the scalp or inward to the dura and perhaps further in). Primary sites were breast cancer (55%), lung cancer (14%), prostate cancer (6%), malignant lymphoma (5%), and others (20%). The mean time from primary diagnosis to skull metastasis diagnosis was 71 months for cases of breast cancer, 26 months for prostate cancer, 9 months for lung cancer, and 4 months for malignant lymphoma. Calvarial circumscribed intraosseous metastases were found most frequently (27%). The patients were mainly asymptomatic. However, some patients suffered from local pain or cranial nerve palsies that harmed their quality of life. Treatment, mainly for symptomatic cases, was by local or whole-skull irradiation. Metastatic skull tumors are not rare, and most are calvarial circumscribed intraosseous tumors. MR images contribute to understanding their type, location, and multiplicity, and their relationship to the brain, cranial nerves, and dural sinuses. Radiation therapy improved the QOL of patients with neurological symptoms.


Assuntos
Imageamento por Ressonância Magnética/métodos , Neoplasias Cranianas/classificação , Neoplasias Cranianas/secundário , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Base do Crânio/patologia , Neoplasias Cranianas/mortalidade , Neoplasias Cranianas/terapia , Adulto Jovem
5.
Acta Radiol ; 52(1): 120-6, 2011 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-21498337

RESUMO

BACKGROUND: For men with clinically localized prostate cancer and candidates to receive radical prostatectomy (RP) a main concern is a cancer recurrence after treatment. Although previous studies have demonstrated the diagnostic utility of diffusion-weighted imaging (DWI) for prostate cancer, the prognostic value of pretreatment DWI has not been investigated yet. PURPOSE: To investigate the incremental value of MRI-based T staging using DWI and T2-weighted imaging (T2WI) as compared with the clinical parameters in prediction of biochemical recurrence (BCR) after RP for clinically localized prostate cancer. MATERIAL AND METHODS: Sixty MR examinations, obtained before RP between April 2002 and March 2009, were retrospectively reviewed using T2WI alone, DWI alone, or T2WI + DWI for T staging according to the 2002 American Joint Committee on Cancer guidelines. The relationship between MRI stage and BCR was evaluated using Kaplan-Meier survival estimates. Multivariate analysis and receiver operating characteristics (ROC) curve analysis were used to investigate the incremental value over the standard clinical variables in prediction of BCR. RESULTS: As of August 2009, 12 (20%) patients had BCR. Based on T2WI + DWI, both T3a (compared to OC disease) and T2 (compared to T1c) showed significantly higher BCR rates (p=0.047 and 0.025, respectively). Multivariate analysis and area under ROC curve analysis confirmed the additional value of MRI staging to the conventional clinical variables in prediction of BCR. CONCLUSION: The combination of T2WI and DWI on performing pretreatment MRI helped predict BCR after RP in clinically localized prostate cancer.


Assuntos
Imageamento por Ressonância Magnética/métodos , Recidiva Local de Neoplasia/patologia , Complicações Pós-Operatórias/patologia , Prostatectomia , Neoplasias da Próstata/cirurgia , Idoso , Imagem de Difusão por Ressonância Magnética/métodos , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Valor Preditivo dos Testes , Próstata/patologia , Próstata/cirurgia , Curva ROC , Estudos Retrospectivos
6.
Eur Radiol ; 20(10): 2315-22, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20455064

RESUMO

OBJECTIVE: To retrospectively evaluate the magnetic resonance (MR) imaging findings of breast cancer before neoadjuvant chemotherapy (NAC) and to compare findings of chemosensitive breast cancer with those of chemoresistant breast cancer. METHODS: The MR imaging findings before NAC in 120 women undergoing NAC were reviewed. The MR imaging findings were compared with the pathological findings and responses. RESULTS: A complete response (pCR) and marked response were achieved in 12 and 35% of 120 breast cancers in 120 women respectively. Breast cancers with a pCR or marked response were classified as chemosensitive breast cancer. The remaining 64 breast cancers (53%) were classified as chemoresistant breast cancer. Large tumour size, a lesion without mass effect, and very high intratumoural signal intensity on T2-weighted MR images were significantly associated with chemoresistant breast cancer. Lesions with mass effect and washout enhancement pattern were significantly associated with chemosensitive breast cancer. Areas with very high intratumoural signal intensity on T2-weighted images corresponded pathologically to areas of intratumoural necrosis. CONCLUSION: Several MR imaging features of breast cancer before NAC can help predict the efficacy of NAC.


Assuntos
Antineoplásicos/farmacologia , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/tratamento farmacológico , Quimioterapia Adjuvante/métodos , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Oncologia/métodos , Pessoa de Meia-Idade , Necrose , Estudos Retrospectivos , Resultado do Tratamento
7.
Neuroradiology ; 52(8): 723-8, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20309533

RESUMO

INTRODUCTION: We sought to investigate the optimum b value for resolving crossing fiber using high-angular resolution diffusion imaging (HARDI)-based multi-tensor tractography. The study tested the standard b values that are commonly used in the routine clinical setting. METHODS: Ten normal volunteers (five men and five women) with a mean age of 26.3 years (range, 22-32 years) were scanned using a 1.5-T clinical magnetic resonance unit. Single-shot echo-planar imaging was used for diffusion-weighted imaging with a diffusion-sensitizing gradient in 32 orientations. The b values of 700, 1,400, 2,100, and 2,800 s/m(2) were used. Data postprocessing was performed using multi-tensor methods. The depiction of the optic nerves, optic tracts, and decussation of superior cerebellar peduncles were assessed. RESULTS: The depictions of the nerve fibers were independent of the b values tested. CONCLUSION: The depiction of crossing fibers by HARDI-based multi-tensor tractography is not substantially influenced by b values ranging from 700 to 2,800 s/m(2). Thus, the optimum b value within this range may be the lowest one considering the higher signal to noise ratio.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Aumento da Imagem/métodos , Processamento de Imagem Assistida por Computador/métodos , Computação Matemática , Fibras Nervosas/ultraestrutura , Vias Neurais/anatomia & histologia , Quiasma Óptico/anatomia & histologia , Software , Adulto , Anisotropia , Artefatos , Dominância Cerebral/fisiologia , Imagem Ecoplanar/métodos , Feminino , Humanos , Masculino , Nervo Óptico/anatomia & histologia , Tamanho do Órgão/fisiologia , Valores de Referência , Adulto Jovem
8.
Breast Cancer ; 27(5): 1029-1037, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32377938

RESUMO

PURPOSE: To assess morphology on diffusion-weighted imaging (DWI) and intratumoral signal intensity (SI) on T2-weighted images (T2WI) of breast carcinomas, and to evaluate the association between the combined DWI and T2WI findings and breast cancer subtypes. METHODS: Two hundred and eighty breast cancer patients who underwent breast MRI prior to therapy were included in this retrospective study. All had invasive carcinomas, which were classified into five subtypes: Luminal A-like (n = 149), Luminal B-like (n = 63), Hormone receptor-positive HER2 (n = 31), Hormone receptor-negative HER2 (n = 13), or Triple-negative (TN) (n = 24). Based on the morphology on DWI, the tumors were classified into two patterns: DWI-homogeneous or DWI-heterogeneous. If DWI-heterogeneous, an assessment of intratumoral SI on T2WI was performed: tumors with intratumoral high/low SI on T2WI were classified as Hete-H/Hete-L, respectively. The associations between (1) the morphological patterns on DWI and the five subtypes, and (2) the intratumoral SI patterns on T2WI and the five subtypes in DWI-heterogeneous were evaluated. RESULTS: There was a significant association between (1) the morphological patterns on DWI and the five subtypes (p < 0.0001), and (2) the intratumoral SI patterns on T2WI and the five subtypes in DWI-heterogeneous (p < 0.0001). DWI-homogeneous was dominant in Luminal A-like (67.1%), and Hete-H was dominant in TN type (75%). Hete-H, suggesting the presence of intratumoral necrosis, included high proliferative and/or aggressive subtypes more frequently (80%) than Hete-L, suggesting the presence of fibrotic focus. Fibrotic focus was seen more commonly in the luminal subtypes. CONCLUSION: The combined findings on DWI and T2WI revealed breast carcinomas that were associated with particular subtypes.


Assuntos
Neoplasias da Mama/diagnóstico , Mama/diagnóstico por imagem , Carcinoma Ductal de Mama/diagnóstico , Imagem de Difusão por Ressonância Magnética , Adulto , Idoso , Mama/patologia , Mama/cirurgia , Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Carcinoma Ductal de Mama/patologia , Quimioterapia Adjuvante , Meios de Contraste/administração & dosagem , Feminino , Humanos , Mastectomia , Pessoa de Meia-Idade , Terapia Neoadjuvante , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Estudos Retrospectivos
9.
Radiology ; 250(3): 638-47, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19244039

RESUMO

PURPOSE: To retrospectively evaluate the magnetic resonance (MR) imaging findings of "triple-negative" breast cancer (ie, cancer that is estrogen receptor [ER] negative, progesterone receptor [PR] negative, and human epidermal growth factor receptor 2 [HER2] negative) and to compare them with those of breast cancers that are ER positive, PR positive, and HER2 negative. MATERIALS AND METHODS: Institutional review board approval and informed consent were obtained. The MR imaging findings in 176 randomly assigned women (mean age, 56 years; range, 29-87 years) with surgically confirmed triple-negative breast cancers (n = 59) or ER-positive/PR-positive/HER2-negative breast cancers (n = 117) were reviewed. MR imaging findings included tumor shape, margin, internal enhancement, and size, as well as intratumoral signal intensity that was stronger than or almost the same as that of water or vessels on T2-weighted MR images. The MR imaging findings were compared with the pathologic findings. RESULTS: High histologic grade (P < .001), unifocal lesion (P = .012), mass lesion type (P < .001), smooth mass margin (P = .001), rim enhancement (P < .001), persistent enhancement pattern (P = .005), and very high intratumoral signal intensity on T2-weighted MR images (P = .002) were significantly associated with triple-negative breast cancer. Very high intratumoral signal intensity on T2-weighted MR images was significantly associated with intratumoral necrosis (P < .001). CONCLUSION: Several MR imaging features might be used for detecting triple-negative breast cancer.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Imageamento por Ressonância Magnética/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/classificação , Feminino , Humanos , Pessoa de Meia-Idade , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estatística como Assunto
10.
Breast Cancer Res Treat ; 112(3): 461-74, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18193352

RESUMO

INTRODUCTION: Breast imaging modalities can assess the tumor extent and adequacy of excision, but there have been no reports comparing magnetic resonance (MR) imaging, multidetector row computed tomography (MDCT), ultrasonography (US) and mammography (MMG) for the tumor extent of breast cancer. We prospectively assessed the accuracy of MR imaging, MDCT, US and MMG for preoperative assessment of the tumor extent of breast cancer. METHODS: Preoperative MR imaging, MDCT, US and MMG were performed for 210 breasts with breast cancer. The MR and MDCT images were independently interpreted by one of two radiologists with knowledge of the clinical and MMG findings. The US was performed with knowledge of the clinical and MMG findings by one of five US technologists. The correlation of the results of these examinations with histological findings was examined. RESULTS: Of the 210 index breast tumors, 210 (100%) could be detected on MR, 208 (99%) were detected on MDCT, 209 (99.5%) were detected on US, and 195 (93%) were detected on MMG. For evaluating local tumor extent, the accuracy of MR imaging (76%) was significantly higher than those of MDCT, US, and MMG (71%, 56%, and 52%, respectively) (P = 0.001, P < 0.0001, and P < 0.0001). MDCT was significantly more accurate than US (P < .0001) or MMG (P < .0001), and US was significantly more accurate than MMG (P = 0.004). MR imaging and US had substantial risk (11% and 17%) of overestimation of the tumor extent. Regarding ductal carcinoma in situ (DCIS), for non-comedo DCIS, the accuracies of MR imaging (89%), MDCT (72%), and US (61%) were significantly higher than the 22% accuracy of MMG (P < 0.0001, P = 0.012, and P = 0.016), but for comedo DCIS, there were no significant differences among the four breast imaging modalities. CONCLUSION: MR imaging was the most accurate breast imaging modality for the tumor exten of breast cancer, although MR imaging had a substantial of risk of overestimation. MR imaging, MDCT and US can complement MMG for the preoperative evaluation of patients who are candidates for breast-conserving surgery.


Assuntos
Neoplasias da Mama/patologia , Imageamento por Ressonância Magnética/métodos , Glândulas Mamárias Humanas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/diagnóstico por imagem , Humanos , Mamografia/métodos , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Risco , Tomografia Computadorizada por Raios X/métodos , Ultrassonografia/métodos
11.
Breast Cancer ; 14(2): 219-28, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17485909

RESUMO

BACKGROUND: Percutaneous imaging-guided core needle biopsy (CNB) is being used increasingly as an alternative to surgical biopsy for the diagnosis of breast lesions that are suspicious or highly suggestive of malignancy. The purpose of this study was to evaluate ultrasonographically (US) guided 18-gauge automated CNB with post-fire needle position verification (PNPV) in the assessment of US visible breast lesions. METHODS: Biopsy of 235 US visible breast lesions was performed using US-guided 18-gauge core needles (18-GCN). After firing the biopsy needle, an image was obtained in the orthogonal plane to confirm the precise post-fire position of the needle track before removing the needle. Needle core diagnoses were compared with surgical diagnoses in 235 lesions subsequently surgically excised. RESULTS: The median size of the lesions was 14 mm (range, 5-60 mm). Agreement between needle core and surgical diagnoses in the 235 lesions was 92% including 192 cancers, 28 benign lesions, and 3 high-risk lesions. In the remaining 12 discordant lesions, 4 were high-risk lesions and 8 were benign lesions. In all 8 benign lesions, imaging-histological discordance was present. The sensitivity of US guided 18-GCNB for breast cancer was 96% (199 of 207). In 71% (167/235) of the cases only one core with PNPV was made. No complications occurred. CONCLUSION: US-guided 18-GCNB for sonographically-demonstrated discrete mass lesions with PNPV is an accurate core needle biopsy technique of breast cancer. During the course of tissue sampling, evaluating the post-fire needle tip position by obtaining an orthogonal view with ultrasonographic guidance is the key to predicting the yield regardless of the size of the needle or the number of core samples.


Assuntos
Biópsia por Agulha Fina/métodos , Mama/patologia , Ultrassonografia de Intervenção , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Carcinoma/patologia , Feminino , Fibroadenoma/patologia , Humanos , Pessoa de Meia-Idade , Papiloma/patologia , Estudos Retrospectivos
12.
AJNR Am J Neuroradiol ; 26(3): 560-5, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15760866

RESUMO

BACKGROUND AND PURPOSE: Diffusion-weighted (DW) imaging has limited spatial resolution, especially in the z direction. We decreased the section thickness of DW imaging to 3 mm to determine if this change improves the depiction of small infarcts and if it affects stroke diagnosis. METHODS: We studied conventional (5-mm section thickness, 1-mm intersection gap) and thin-section (3-mm section thickness, no intersection gap) DW imaging data in 49 patients with symptoms of acute cerebral ischemia. Two radiologists who were not aware of the clinical findings reviewed all images and diagnosed the stroke subtype according to the Trial of Org 10172 in Acute Stroke Treatment (TOAST) method. Accuracies of stroke diagnosis with an experienced neuroradiologist and with a second-year radiology resident were compared. To quantify lesion conspicuity, contrast-to-noise ratios (CNRs) were measured. The CNR of thin-section DW imaging was then divided by the CNR of conventional DW imaging to yield the relative CNR (rCNR). RESULTS: The experienced neuroradiologist made the correct final diagnoses in 78% of cases with conventional DW imaging, improving to 100% with thin-section DW imaging. The resident made the correct diagnoses in 71% of cases with conventional DW imaging, improving to 94% with thin-section DW imaging. Lesion conspicuity was improved on thin-section DW imaging (rCNR = 1.47 +/- 0.63), especially for supratentorial lesions (rCNR = 1.51 +/- 0.63). CONCLUSION: Compared with conventional DW imaging, thin-section DW imaging permitted better lesion conspicuity and more precise stroke diagnosis.


Assuntos
Imagem de Difusão por Ressonância Magnética , Microtomia , Acidente Vascular Cerebral/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Imagem de Difusão por Ressonância Magnética/normas , Feminino , Humanos , Masculino , Microtomia/normas , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Método Simples-Cego
13.
J Thorac Imaging ; 20(2): 103-6, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15818209

RESUMO

We encountered a late pulmonary complication after umbilical cord blood transplantation (UCBT) that has not been previously reported. High-resolution CT (HRCT) findings of this disease were compared with the pathology. HRCT obtained on inspiration showed dilated thick-walled bronchioli, and innumerable centrilobular linear and branching structures in the bilateral middle and lower lobes. Neither mosaic perfusion nor air-trapping was seen in HRCT on inspiration and expiration. These HRCT findings were atypical compared with those of former bronchiolitis obliterans (BO) after bone marrow transplant (BMT). Pathologic specimens obtained by open lung biopsy showed thickening of the wall from the distal bronchioli to the alveolar ducts due to submucosal and intraepithelial infiltration of lymphocytes, histiocytes and foamy macrophages, which was not accompanied by organizing changes. These changes resemble lymphocytic bronchiolitis in lung transplant recipients, which was well correlated with HRCT findings. We think that our case was a new late pulmonary complication after UCBT.


Assuntos
Transplante de Células-Tronco de Sangue do Cordão Umbilical/efeitos adversos , Leucemia Mieloide Aguda/terapia , Pulmão/diagnóstico por imagem , Pulmão/patologia , Complicações Pós-Operatórias/diagnóstico , Tomografia Computadorizada por Raios X/métodos , Adolescente , Anti-Inflamatórios/uso terapêutico , Biópsia/métodos , Bronquiolite/diagnóstico , Bronquiolite/tratamento farmacológico , Bronquiolite/etiologia , Feminino , Doença Enxerto-Hospedeiro/complicações , Doença Enxerto-Hospedeiro/diagnóstico , Humanos , Prednisolona/uso terapêutico , Doenças Raras , Fatores de Tempo
14.
Stroke ; 34(9): E159-62, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12907811

RESUMO

BACKGROUND AND PURPOSE: We tested the feasibility of a new MRI technique that provides visualization of the sensorimotor tracts in vivo in a group of stroke victims. SUMMARY OF REPORT: Fourteen patients with small infarctions involving the white matter of the supratentorial brain were evaluated. Sensorimotor tracts on the lesional and contralesional sides were successfully depicted in all cases. The position of the sensorimotor tracts relative to the infarct was in good agreement with clinical symptoms. The overall sensitivity and specificity for sensorimotor tract involvement were 100% and 77%, respectively. CONCLUSIONS: Our proposed fiber-tracking method was shown to be a clinically feasible technique that correlates well with clinical symptoms.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Vias Neurais , Córtex Somatossensorial , Acidente Vascular Cerebral/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Disartria/etiologia , Estudos de Viabilidade , Feminino , Humanos , Aumento da Imagem , Masculino , Pessoa de Meia-Idade , Fibras Nervosas , Vias Neurais/fisiopatologia , Paresia/etiologia , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Córtex Somatossensorial/fisiopatologia , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/fisiopatologia , Fatores de Tempo
15.
Stroke ; 33(7): 1799-802, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12105356

RESUMO

BACKGROUND AND PURPOSE: Diffusion-weighted imaging (DWI) is usually done before administration of intravenous contrast agents. Repetition of DWI is occasionally necessary after administration, but the effects of contrast material on DWI and apparent diffusion coefficient (ADC) values have not yet been fully examined. The present study assesses whether administration of gadolinium-based contrast material significantly affects DWI and ADC values. METHODS: We examined DWI data from 39 patients (mean age, 67.9 years; range, 34 to 87 years) who were evaluated with a stroke protocol at our institute. All patients were scanned at the acute or subacute stages of infarct from 3 hours to 5 days after symptom onset. We obtained DWI images using single-shot echo-planar imaging with a b value of 1000 s/mm2. Patients were injected with 0.1 mmol gadopentetate dimeglumine per 1 kg body weight. We examined the signal-to-noise ratio of the normal brain and the infarct and evaluated the contrast-to-noise ratio of each lesion. In addition, we compared the ADC values calculated from the DWI images before and after administration of contrast. The statistical significance of differences between precontrast and postcontrast administration was determined by use of a paired t test. RESULTS: The signal-to-noise and contrast-to-noise ratios of the DW images were not significantly different before and after administration of contrast agent. The ADC values were slightly lower after administration of contrast agent for both normal brain (P=0.0011) and infarcts (P=0.038). The estimated differences in the ADC values were approximately 1.3% and 3.5% for normal brain and infarcts, respectively. CONCLUSIONS: The lack of a significant difference between the signal-to-noise and contrast-to-noise ratios of DW images before and after administration of contrast agent indicates the feasibility of postcontrast DWI.


Assuntos
Encéfalo , Infarto Cerebral/diagnóstico , Imagem Ecoplanar , Gadolínio DTPA , Adulto , Idoso , Idoso de 80 Anos ou mais , Encéfalo/anatomia & histologia , Encéfalo/patologia , Meios de Contraste/administração & dosagem , Difusão , Imagem Ecoplanar/métodos , Estudos de Viabilidade , Humanos , Aumento da Imagem , Processamento de Imagem Assistida por Computador , Infarto da Artéria Cerebral Média/diagnóstico , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
18.
Neuroreport ; 21(13): 851-5, 2010 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-20683360

RESUMO

The balance between heat production (metabolism) and heat removal (blood flow) helps in keeping the temperature of the brain constant. In patients with moyamoya disease, this balance may be disturbed. The purpose of this study was to assess the thermal pathophysiology of the brain in patients with moyamoya disease. The study included 12 consecutive patients with moyamoya disease and 10 controls. Temperature was measured by image postprocessing of diffusion-weighted images. Our noninvasive thermometry showed that the ventricular temperature of moyamoya disease patients was higher than that of normal controls. The mean temperature difference of 1.1 degrees C between the two groups was significant. Patients with moyamoya disease tend to have elevated ventricular temperatures, which may represent a mismatch between cerebral metabolism and perfusion.


Assuntos
Temperatura Corporal/fisiologia , Encéfalo/fisiologia , Doença de Moyamoya/fisiopatologia , Adolescente , Adulto , Envelhecimento/fisiologia , Artéria Carótida Interna/fisiologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Artéria Cerebral Posterior/fisiologia , Estudos Retrospectivos , Adulto Jovem
19.
Breast Cancer ; 16(2): 97-104, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-18663562

RESUMO

BACKGROUND: FDG PET has not yet found a role in the clinical evaluation of the tumor extent of breast cancer. FDG PET has been reported to be useful for evaluating the prognoses of breast cancer patients with more accuracy than conventional imaging modalities. The purpose of this study was to compare the accuracy of FDG PET and MRI for the preoperative assessment of the tumor extent of breast cancer, for evaluating the impact of FDG PET on systemic staging, and also for predicting the prognosis of patients who are candidates for breast-conserving therapy. METHODS: The study was a prospective series of 23 breasts with breast cancer that underwent both FDG PET and MRI before surgery. Systemic staging with FDG PET was also performed. The correlation between the results of these examinations and histological findings was thus examined. The maximum standardized uptake value (SUVmax) of the tumors was investigated in association with the patient prognoses. RESULTS: When evaluating the local tumor extent, the accuracy of FDG PET (43.5%) was significantly lower than that of MRI (91%) (P < 0.001). The sensitivity, specificity, and accuracy of FDG PET regarding the nodal status were 60, 94, and 87%, respectively. No patients demonstrated any distant metastasis, whereas FDG PET gave a false positive in one patient. The mean follow-up period was 61 months. The SUVmax value of the worse prognosis patient group was significantly higher than that of the good prognosis patient group (P = 0.032). CONCLUSIONS: FDG PET is not a breast imaging modality for evaluating the local tumor extent, but it is useful for predicting the prognoses of patients who are candidates for breast-conserving therapy.


Assuntos
Neoplasias da Mama/diagnóstico , Fluordesoxiglucose F18 , Imageamento por Ressonância Magnética , Tomografia por Emissão de Pósitrons , Compostos Radiofarmacêuticos , Adulto , Idoso , Carcinoma Ductal de Mama/diagnóstico , Carcinoma Intraductal não Infiltrante/diagnóstico , Carcinoma Lobular/diagnóstico , Reações Falso-Positivas , Feminino , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
20.
Breast Cancer ; 16(4): 307-14, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19350360

RESUMO

BACKGROUND: Abnormal screening mammographic findings are the most common presentation of ductal carcinoma in situ, which usually appears as a cluster of microcalcifications. No report has documented the risk of malignancy between the finding of a cluster of microcalcifications and women with high risk of breast cancer. METHODS: We investigated the morphologic descriptors of a cluster of microcalcifications in women with a high risk for breast cancer and compared the results with the characteristics of a cluster of microcalcifications in other women. A retrospective review was performed for 81 non-palpable clusters of microcalcifications that had stereotactic vacuum-assisted breast biopsy. RESULTS: The frequency of malignancy associated with a cluster of microcalcifications was 27%. The 50% frequency of malignancy with high risk for breast cancer was higher, but not significantly so, than the 24% frequency of 71 cases without high risk for breast cancer (P = 0.125). The frequency of malignancy and ADH of a cluster of microcalcifications with high risk of breast cancer was 70%, significantly higher than the 30% frequency of 71 cases without high risk of breast cancer (P = 0.028). CONCLUSIONS: A cluster of microcalcifications in women with high risk for breast cancer should be considered suspicious and referred for biopsy.


Assuntos
Neoplasias da Mama/patologia , Calcinose/patologia , Carcinoma Ductal de Mama/patologia , Carcinoma Intraductal não Infiltrante/patologia , Carcinoma Lobular/patologia , Adulto , Idoso , Biópsia por Agulha , Neoplasias da Mama/diagnóstico por imagem , Calcinose/diagnóstico por imagem , Carcinoma Ductal de Mama/diagnóstico por imagem , Carcinoma Intraductal não Infiltrante/diagnóstico por imagem , Carcinoma Lobular/diagnóstico por imagem , Feminino , Humanos , Mamografia , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Técnicas Estereotáxicas , Taxa de Sobrevida , Vácuo
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