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1.
Clin Radiol ; 78(6): 444-450, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37029001

RESUMO

AIM: To evaluate the effectiveness of an ultrafast breast magnetic resonance imaging (MRI) protocol in differentiating benign and malignant breast lesions. MATERIALS AND METHODS: Fifty-four patients with Breast Imaging Reporting and Data System (BI-RADS) 4 or 5 lesions were recruited between July 2020 to May 2021. A standard breast MRI was performed with the inclusion of the ultrafast protocol between the unenhanced sequence and the first contrast-enhanced sequence. Three radiologists performed image interpretation in consensus. Ultrafast kinetic parameters analysed included the maximum slope (MS), time to enhancement (TTE), and arteriovenous index (AVI). These parameters were compared using receiver operating characteristics with p-values of <0.05 considered to indicate statistical significance. RESULTS: Eighty-three histopathological proven lesions from 54 patients (mean age 53.87 years, SD 12.34, range 26-78 years) were analysed. Forty-one per cent (n=34) were benign and 59% (n=49) were malignant. All malignant and 38.2% (n=13) benign lesions were visualised on the ultrafast protocol. Of the malignant lesions, 77.6% (n=53) were invasive ductal carcinoma (IDC) and 18.4% (n=9) were ductal carcinoma in situ (DCIS). The MS for malignant lesions (13.27%/s) were significantly larger than for benign (5.45%/s; p<0.0001). No significant differences were seen for TTE and AVI. The area under the ROC curve (AUC) for the MS, TTE, and AVI were 0.836, 0.647, and 0.684, respectively. Different types of invasive carcinoma had similar MS and TTE. The MS of high-grade DCIS was also similar to that of IDC. Lower MS values were observed for low-grade (5.3%/s) compared to high-grade DCIS (14.8%/s) but the results were not significant statistically. CONCLUSION: The ultrafast protocol showed potential to discriminate between malignant and benign breast lesions with high accuracy using MS.


Assuntos
Carcinoma de Mama in situ , Neoplasias da Mama , Carcinoma Intraductal não Infiltrante , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Feminino , Meios de Contraste , Diagnóstico Diferencial , Estudos Retrospectivos , Imageamento por Ressonância Magnética/métodos
2.
Sci Rep ; 9(1): 1459, 2019 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-30728394

RESUMO

Synthesized 2D images can be reconstructed from tomosynthesis images in breast imaging. This study aims to investigate the diagnostic efficacy of synthesized 2D images (C-View) in comparison to full field digital mammography (FFDM) when used with digital breast tomosynthesis (DBT) in multi-ethnic Malaysian population. FFDM and C-View images (n = 380) were independently evaluated by three readers through Breast Imaging Reporting and Data System (BI-RADS) categorisation, breast density and lesion characterisation. Statistical analysis was done comparing sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of C-View + DBT with FFDM + DBT as standard of reference. Very good interreader agreement in BI-RADS category and density assessment between C-View + DBT and FFDM + DBT, with high sensitivity, specificity, PPV and NPV of C-View + DBT when compared with FFDM + DBT. There was comparable PPV between C-View + DBT and FFDM + DBT, with histopathology as gold standard. High level of interreader agreement in BI-RADS category and density assessment for FFDM + DBT and C-View + DBT. There was good agreement between FFDM + DBT and C-View + DBT in mass characterization, and almost perfect agreement in calcification and asymmetric density. 52.2% lower radiation dose incurred when using C-View + DBT. Hence, synthesized 2D images are comparable to FFDM with reduction in radiation dose within the limits of Malaysian multi-ethnic population.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Adulto , Idoso , Neoplasias da Mama/etnologia , Detecção Precoce de Câncer , Feminino , Humanos , Malásia/etnologia , Mamografia , Pessoa de Meia-Idade , Sensibilidade e Especificidade
3.
Eur J Neurol ; 23(2): 354-60, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26498575

RESUMO

BACKGROUND AND PURPOSE: In the current study, the aim was to characterize the nerve ultrasound cross-sectional areas (CSAs) of type 2 diabetic patients with diabetic sensorimotor polyneuropathy (DSP) of different severities. METHODS: A hundred symptomatic DSP patients and 40 age-matched healthy controls were prospectively recruited. DSP severity was ascertained through the Toronto Clinical Scoring System (TCCS). Nerve electrophysiology and ultrasound were performed on both lower limbs and the non-dominant upper limb. RESULTS: The sural nerve was inexcitable in 19.1% of mild, 40.0% of moderate and 69.0% of severe DSP groups. In contrast, CSAs were measurable in all nerves of DSP patients and were significantly larger compared to controls. Patients with severe DSP had significantly larger ulnar, peroneal, tibial and sural nerves compared to mild DSP patients. By receiver operating characteristic curve analysis, the cut-off value for the sural nerve at 2 mm(2) was a good discriminator (area under the curve 0.88) between the presence and absence of DSP (sensitivity 0.90; specificity 0.74) but performed less well in discriminating between the severity of DSP (cut-off 2.75 mm(2); area under the curve 0.62; sensitivity 0.59; specificity 0.73). Significant correlations were demonstrated between TCSS scores, most neurophysiology parameters and CSAs of the ulnar, peroneal, tibial and sural nerves. CONCLUSION: Nerve ultrasound in DSP reveals enlarged CSAs and these changes worsen with increasing disease severity, thus serving as a useful diagnostic tool especially when neurophysiology is unrevealing.


Assuntos
Diabetes Mellitus Tipo 2/diagnóstico por imagem , Diabetes Mellitus Tipo 2/fisiopatologia , Neuropatias Diabéticas/diagnóstico por imagem , Neuropatias Diabéticas/fisiopatologia , Condução Nervosa/fisiologia , Nervos Periféricos/diagnóstico por imagem , Nervos Periféricos/fisiopatologia , Idoso , Diabetes Mellitus Tipo 2/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Ultrassonografia
5.
Clin Radiol ; 69(1): 63-71, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24156797

RESUMO

AIM: To investigate the capability and diagnostic accuracy of diffusion-weighted imaging (DWI) in differentiating benign from malignant breast lesions using 3 T magnetic resonance imaging (MRI). MATERIALS AND METHODS: Women with suspicious or indeterminate breast lesions detected at MRI, mammogram and/or ultrasound were recruited for dynamic contrast-enhanced (DCE)-MRI and DWI prior to their biopsy. Image fusion of DCE-MRI with apparent diffusion coefficient (ADC) map was utilized to select the region of interest (ROI) for ADC calculation in the area that showed the most avid enhancement. DWI was performed using two sets of b-values at 500 and 1000 s/mm(2), respectively. RESULTS: Fifty women were recruited and the final analysis comprised 44 breast lesions, 31 of which were malignant and 13 were benign. Significant results were obtained between ADC values of benign and malignant lesions (p < 0.001). The cut-off ADC values for benign and malignant lesions were 1.21 × 10(-3) mm(2)/s for b = 500 s/mm(2) and 1.22 × 10(-3) mm(2)/s for b = 1000 s/mm(2), respectively. The sensitivity of DCE-MRI alone was 100% with a specificity of 66.7%. When DCE-MRI was combined with b = 1000 s/mm(2), the specificity rose to 100%, while only mildly affecting sensitivity (90.6%). No significant correlation was found between ADC values and prognostic factors, such as lymph node metastasis, tumour size, oestrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2) status, and tumour grades. CONCLUSION: The present study provides consistent evidence to support DWI as a diagnostic tool for breast lesion characterization. A combination of DCE-MRI with DWI is suggested to improve the sensitivity and specificity of lesion characterization.


Assuntos
Neoplasias da Mama/diagnóstico , Imagem de Difusão por Ressonância Magnética/métodos , Adulto , Idoso , Meios de Contraste , Diagnóstico Diferencial , Feminino , Gadolínio DTPA , Humanos , Metástase Linfática , Mamografia , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Sensibilidade e Especificidade , Ultrassonografia Mamária
6.
Clin Radiol ; 64(6): 574-88, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19414080

RESUMO

Lymphomas are generally considered tumours of lymph nodes, but up to 40% arise extranodally. This group shows distinctive pathological, radiological, and clinical features. Different subtypes of extranodal lymphoma may show sufficiently specific radiological features to be of significant value in both establishing a diagnosis of lymphoma and ascertaining the exact subtype. Rapidly evolving lymphoma classifications and emergence of new entities have, however, hampered the accurate description of these features in the literature. In this review, we discuss the radiological appearances, using a variety of imaging methods, of the full spectrum of primary extranodal lymphomas, categorized according to the current World Health Organisation classification.


Assuntos
Diagnóstico por Imagem/métodos , Linfoma/diagnóstico , Neoplasias das Glândulas Suprarrenais/diagnóstico , Adulto , Idoso , Neoplasias Ósseas/diagnóstico , Neoplasias da Mama/diagnóstico , Neoplasias do Sistema Nervoso Central/diagnóstico , Meios de Contraste , Diagnóstico Diferencial , Neoplasias do Sistema Digestório/diagnóstico , Neoplasias Oculares/diagnóstico , Feminino , Fluordesoxiglucose F18 , Neoplasias de Cabeça e Pescoço/diagnóstico , Humanos , Neoplasias Pulmonares/diagnóstico , Linfoma/patologia , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos , Neoplasias Esplênicas/diagnóstico , Tomografia Computadorizada por Raios X/métodos , Neoplasias Urogenitais/diagnóstico
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