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1.
Int. braz. j. urol ; 45(3): 486-494, May-June 2019. tab, graf
Artigo em Inglês | LILACS-Express | ID: biblio-1012318

RESUMO

ABSTRACT Objectives: To identify the group of patients who could safely avoid prostate biopsy based on the findings of multiparametric prostate resonance imaging (MRmp), parameterized with PI-RADS v2, using prostate biopsy as reference test and to assess the sensitivity and specificity of mpMR in identifying clinically significant prostate cancer using prostate biopsy as a reference test. Patients and Methods: Three hundred and forty two patients with suspected prostate cancer were evaluated with mpMR and prostate biopsy. Agreement between imaging findings and histopathological findings was assessed using the Kappa index. The accuracy of mpMR in relation to biopsy was assessed by calculations of sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV). Results: A total of 342 biopsies were performed. In 201 (61.4%), mpMR had a negative result for cancer, which was confirmed on biopsy in 182 (53%) of the cases, 17 (4.9%) presented non-clinically significant cancer and only 2 (0.5%) clinically significant cancer. 131 (38.3%) patients had a positive biopsy. Clinically significant cancer corresponded to 83 (34.2%), of which 81 (97.5%) had a positive result in mpMR. Considering only the clinically significant cancers the mpMR had a sensitivity of 97.6%, specificity of 76.8%, PPV 57.4% and VPN of 99%. Conclusions: mpMR is a useful tool to safely identify which patients at risk for prostate cancer need to undergo biopsy and has high sensitivity and specificity in identifying clinically significant prostate cancer.

2.
Int Braz J Urol ; 45(3): 486-494, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31038866

RESUMO

OBJECTIVES: To identify the group of patients who could safely avoid prostate biopsy based on the findings of multiparametric prostate resonance imaging (MRmp), parameterized with PI-RADS v2, using prostate biopsy as reference test and to assess the sensitivity and specificity of mpMR in identifying clinically significant prostate cancer using prostate biopsy as a reference test. PATIENTS AND METHODS: Three hundred and forty two patients with suspected prostate cancer were evaluated with mpMR and prostate biopsy. Agreement between imaging findings and histopathological findings was assessed using the Kappa index. The accuracy of mpMR in relation to biopsy was assessed by calculations of sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV). RESULTS: A total of 342 biopsies were performed. In 201 (61.4%), mpMR had a negative result for cancer, which was confirmed on biopsy in 182 (53%) of the cases, 17 (4.9%) presented non-clinically significant cancer and only 2 (0.5%) clinically significant cancer. 131 (38.3%) patients had a positive biopsy. Clinically significant cancer corresponded to 83 (34.2%), of which 81 (97.5%) had a positive result in mpMR. Considering only the clinically significant cancers the mpMR had a sensitivity of 97.6%, specificity of 76.8%, PPV 57.4% and VPN of 99%. CONCLUSIONS: mpMR is a useful tool to safely identify which patients at risk for prostate cancer need to undergo biopsy and has high sensitivity and specificity in identifying clinically significant prostate cancer.


Assuntos
Biópsia Guiada por Imagem/métodos , Imagem por Ressonância Magnética/métodos , Próstata/diagnóstico por imagem , Próstata/patologia , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Padrões de Referência , Reprodutibilidade dos Testes , Estudos Retrospectivos , Fatores de Risco , Sensibilidade e Especificidade
3.
Rev. bras. mastologia ; 27(1)jan.-mar. 2017.
Artigo em Português | LILACS-Express | ID: biblio-831958

RESUMO

O câncer de mama é um dos mais frequentes entre as mulheres, e seu diagnóstico pode ser realizado por meio de ultrassonografia, mamografia ou ressonância magnética, juntamente com biópsia. Em pacientes que apresentam mamas densas, a ressonância magnética é considerada o melhor método de diagnóstico, por apresentar alta sensibilidade quando comparado às outras técnicas, devido principalmente à aplicação do meio de contraste gadolínio, que se impregna no tecido acometido, facilitando a visualização do tumor e a possibilidade de saturar seletivamente o sinal da gordura, auxiliando desse modo no diagnóstico do câncer de mama.


Breast cancer is the most frequent cancer among women, and its diagnosis can be made by ultrasound, mammography or MRI, along with biopsy. In patients with dense breasts, MRI is considered the best diagnostic method for its high sensitivity when compared to other techniques. Plus, there's the application of gadolinium contrast medium, which is impregnated in the affected tissue for easier viewing the tumor and the possibility of selectively saturate the fat signal, helping thus the diagnosis of breast cancer.

4.
Radiol. bras ; 47(6): 333-341, Nov-Dec/2014. tab, graf
Artigo em Português | LILACS-Express | ID: lil-732744

RESUMO

Objetivo: Avaliar um protocolo de espectroscopia por ressonância magnética (ERM) do próton de hidrogênio (1H) bidimensional (2D) disponível comercialmente (Siemens Medical Systems; Erlangen, Alemanha), aplicado para nódulos adrenais e diferenciação das massas (adenomas, feocromocitomas, carcinomas e metástases). Materiais e Métodos: Um total de 118 pacientes (36 homens e 82 mulheres), apresentando-se com 138 nódulos/massas adrenais, foi avaliado prospectivamente (média de idade: 57,3 ± 13,3 anos). Uma sequência de ERM-1H-PRESS-CSI (espectroscopia por resolução de ponto-imagem por desvio químico) multivoxel foi utilizada. Análise espectroscópica foi realizada da esquerda-direita, sentido crânio-caudal, usando três sequências sagitais, além de sequências axiais e coronais T2-HASTE. Os seguintes índices foram calculados: colina (Cho)/creatina (Cr), 4,0–4,3 ppm/Cr, lipídio (Lip)/Cr, Cho/Lip e lactato (Lac)/Cr. Resultados: ERM-1H-2D foi bem sucedida em 123 (89,13%) lesões. Os valores de sensibilidade e especificidade encontrados para as proporções e pontos de corte avaliados foram: Cho/Cr ≥ 1,2, sensibilidade de 100% e especificidade de 98,2% (diferenciação de adenomas e carcinomas de feocromocitomas e metástases); 4,0–4,3 ppm/Cr ≥ 1,5, 92,3% de sensibilidade, especificidade de 96,9% (diferenciação de carcinomas e feocromocitomas de adenomas e metástases); Lac/Cr ≤ –7,449, sensibilidade de 90,9% e especificidade de 77,8% (diferenciação de feocromocitomas contra carcinomas e adenomas). Conclusão: Os dados da ERM-1H-2D foram eficazes e permitiram a diferenciação entre massas adrenais e nódulos na maioria das lesões com diâmetro > 1,0 cm. .


Objective: To evaluate a protocol for two-dimensional (2D) hydrogen proton (1H) magnetic resonance spectroscopy (MRS) (Siemens Medical Systems; Erlangen, Germany) in the detection of adrenal nodules and differentiation between benign and malignant masses (adenomas, pheochromocytomas, carcinomas and metastases). Materials and Methods: A total of 118 patients (36 men; 82 women) (mean age: 57.3 ± 13.3 years) presenting with 138 adrenal nodules/masses were prospectively assessed. A multivoxel system was utilized with a 2D point-resolved spectroscopy/chemical shift imaging sequence. The following ratios were calculated: choline (Cho)/creatine (Cr), 4.0–4.3/Cr, lipid (Lip)/Cr, Cho/Lip and lactate (Lac)/Cr. Results: 2D-1H-MRS was successful in 123 (89.13%) lesions. Sensitivity and specificity values observed for the ratios and cutoff points were the following: Cho/Cr ≥ 1.2, 100% sensitivity, 98.2% specificity (differences between adenomas/pheochromocytomas and carcinomas/ metastases); 4.0–4.3 ppm/Cr ≥ 1.5, 92.3% sensitivity, 96.9% specificity (differences between carcinomas/pheochromocytomas and adenomas/metastases); Lac/Cr ≤ –7.449, 90.9% sensitivity and 77.8% specificity (differences between pheochromocytomas and carcinomas/adenomas). Conclusion: Information provided by 2D-1H-MRS were effective and allowed for the differentiation between adrenal masses and nodules in most cases of lesions with > 1.0 cm in diameter. .

5.
Radiol Bras ; 47(6): 333-41, 2014 Nov-Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25741115

RESUMO

OBJECTIVE: To evaluate a protocol for two-dimensional (2D) hydrogen proton (1H) magnetic resonance spectroscopy (MRS) (Siemens Medical Systems; Erlangen, Germany) in the detection of adrenal nodules and differentiation between benign and malignant masses (adenomas, pheochromocytomas, carcinomas and metastases). MATERIALS AND METHODS: A total of 118 patients (36 men; 82 women) (mean age: 57.3 ± 13.3 years) presenting with 138 adrenal nodules/masses were prospectively assessed. A multivoxel system was utilized with a 2D point-resolved spectroscopy/chemical shift imaging sequence. The following ratios were calculated: choline (Cho)/creatine (Cr), 4.0-4.3/Cr, lipid (Lip)/Cr, Cho/Lip and lactate (Lac)/Cr. RESULTS: 2D-1H-MRS was successful in 123 (89.13%) lesions. Sensitivity and specificity values observed for the ratios and cutoff points were the following: Cho/Cr ≥ 1.2, 100% sensitivity, 98.2% specificity (differences between adenomas/pheochromocytomas and carcinomas/ metastases); 4.0-4.3 ppm/Cr ≥ 1.5, 92.3% sensitivity, 96.9% specificity (differences between carcinomas/pheochromocytomas and adenomas/metastases); Lac/Cr ≤ -7.449, 90.9% sensitivity and 77.8% specificity (differences between pheochromocytomas and carcinomas/adenomas). CONCLUSION: Information provided by 2D-1H-MRS were effective and allowed for the differentiation between adrenal masses and nodules in most cases of lesions with > 1.0 cm in diameter.

6.
Arq. bras. neurocir ; 32(1)mar. 2013. ilus
Artigo em Português | LILACS | ID: lil-677806

RESUMO

Objetivo: Análise morfométrica do acesso lateral para amígdalo-hipocampectomia, com ênfase na localização do ?ponto hipocampal?. Métodos: Análise de 22 exames de ressonância magnética (RM) e tomografia computadorizada (TC) com o sistema AIMNAV (Micromar Inst), para determinação do ponto hipocampal, e o Advantage Workstation AW 4.3 (GE Medical Systems), para mensuração do corredor cirúrgico. Resultados: O ?ponto hipocampal? se localiza a 31,9 mm do canal auditivo. Conclusão: Os dados morfométricos obtidos neste estudo têm utilidade prática na tática da abordagem lateral para amígdalo-hipocampectomia...


Objective: Morphometric analysis of lateral access to amygdalo-hippocampectomy, with emphasis on the location of ?hippocampal point?. Methods: Analysis of 22 magnetic resonance imaging (MRI) and computed tomography (CT) system with AIMNAV (Micromar Inst) to determine hippocampal point, and the Advantage Workstation AW 4.3 (GE Medical Systems) for measurement of the surgical corridor. Results: The ?hippocampal point? is located at 31,9 mm from the ear canal. Conclusion:The morphometric data obtained in this study have practical utility of the tactical approach to lateral amygdalo-hippocampectomy...


Assuntos
Humanos , Masculino , Feminino , Craniotomia , Epilepsia do Lobo Temporal , Hipocampo/cirurgia , Imagem por Ressonância Magnética , Tomografia
7.
Braz. j. morphol. sci ; 29(2): 87-90, apr.-jun. 2012. ilus, tab
Artigo em Inglês | LILACS | ID: lil-665206

RESUMO

to establish the spatial relationship between the surfaces of foramen magnum (FM) and spinal cord (SC) identifying how much of the FM surface is occupied by the SC. Material and methods: 40 normal adults (23 females) with a mean age of 22 yrs (18-25) were evaluated through MRI to evaluate the sagittal and transversal diameter of foramen magnum and spinal cord. The surface area of FM and spinal cord was calculated, in the craniovertebral junction. Results: the sagittal diameter was consistently greater than the transversal diameter in the FM with a mean value of 34.78 mm. On the other hand, the transversal diameter was bigger in the spinal cord, with the mean value of 12.18 mm. The spinal cord occupies 82.93% of the FM surface in the craniovertebral junction. There was no difference between sexes. Conclusions: The better knowledge of craniovertebral junction anatomy is helpful in the neurosurgical planning and in the diagnosis of diseases that present intracranial hypertension.


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto Jovem , Forame Magno/anatomia & histologia , Medula Espinal/anatomia & histologia , Espectroscopia de Ressonância Magnética/métodos
8.
Radiol. bras ; 42(1): 1-6, jan.-fev. 2009. ilus, tab
Artigo em Português | LILACS-Express | ID: lil-511793

RESUMO

OBJETIVO: Demonstrar a experiência na implantação de um protocolo de espectroscopia por ressonância magnética do 1H tridimensional (3D 1H MRSI), disponível comercialmente, aplicando-o em pacientes com suspeita de neoplasia prostática e com diagnóstico estabelecido de tumor prostático. MATERIAIS E MÉTODOS: Estudo realizado de forma prospectiva, em 41 pacientes com idades entre 51 e 80 anos (média de 67 anos). Dois grupos foram formados: pacientes com uma ou mais biópsias negativas para câncer e antígeno prostático específico elevado (grupo A) e pacientes com câncer confirmado por biópsia (grupo B). Procurou-se, a partir dos resultados da ressonância magnética e espectroscopia por ressonância magnética, determinar a área-alvo (grupo A) ou a extensão do câncer conhecido (grupo B). RESULTADOS: No diagnóstico de câncer de próstata a espectroscopia por ressonância magnética apresentou especificidade abaixo da descrita pela literatura, cerca de 47%. Já para o estadiamento do tumor diagnosticado, houve correspondência com a literatura. CONCLUSÃO: A implantação e padronização da espectroscopia por ressonância magnética permitiram a obtenção de informações importantes para o diagnóstico presuntivo da existência de câncer de próstata, combinando as imagens por ressonância magnética com os dados metabólicos da espectroscopia por ressonância magnética.


OBJECTIVE: To report an experiment involving the introduction of a protocol utilizing commercially available three-dimensional 1H magnetic resonance spectroscopy imaging (3D 1H MRSI) method in patients diagnosed with prostatic tumors under suspicion of neoplasm. MATERIALS AND METHODS: Forty-one patients in the age range between 51 and 80 years (mean, 67 years) were prospectively evaluated. The patients were divided into two groups: patients with one or more biopsies negative for cancer and high specific-prostatic antigen levels (group A), and patients with cancer confirmed by biopsy (group B). The determination of the target-area (group A) or the known cancer extent (group B) was based on magnetic resonance imaging and MRSI studies. RESULTS: The specificity of MRSI in the diagnosis of prostate cancer was lower than the specificity reported in the literature (about 47%). On the other hand, for tumor staging, it corresponded to the specificity reported in the literature. CONCLUSION: The introduction and standardization of 3D 1H MRSI has allowed the obtention of a presumable diagnosis of prostate cancer, by a combined analysis of magnetic resonance imaging and metabolic data from 3D 1H MRSI.

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