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1.
J Radiol Prot ; 38(4): 1311-1320, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30198859

RESUMO

The present paper reports the structural, morphological and optical properties of nanophosphor Li3B7O12:Mn with an optimised dopant concentration of 0.25 mol% and its surface modification under the irradiation of 250 keV proton beams and gamma photons for ion fluence ranging from 1 × 1013 to 6.25 × 1015 ions cm-2 and doses from 100 mGy-100 Gy, respectively. This nanophosphor has been synthesised by the high temperature solid state reaction method. Its optical properties are characterised by optically stimulated luminescence (OSL) and thermo luminescence (TL) techniques. This nanophosphor is polycrystalline in nature with a grain size of 40-80 nm confirmed by x-ray diffraction (XRD) and transmission electron microscopy (TEM). The OSL decay and TL glow curve response of the proton beam irradiated samples exhibit significant intensity at a fluence of 2.5 × 1014 ions cm-2. Moreover, Li3B7O12:Mn displays a linear response for gamma doses in the range of 100 mGy-50 Gy. We have also investigated the reusability and reproducibility of this material. The above study demonstrates that Li3B7O12:Mn is a robust and promising candidate for medical proton dosimetry.


Assuntos
Nanotecnologia , Dosimetria por Luminescência Estimulada Opticamente , Compostos de Fósforo/síntese química , Boro , Lítio , Manganês , Oxigênio
2.
Diagn Interv Imaging ; 99(11): 699-707, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30006125

RESUMO

PURPOSE: To evaluate the role of SWE in characterizing breast masses and ascertain whether additional use of SWE to ultrasound for evaluating BI-RADS 3 and 4a masses could help reduce long-term follow-up and unnecessary biopsies of these suspicious breast masses. MATERIALS AND METHODS: This prospective, cross-sectional study was performed between June 2013 and November 2014. All enrolled patients underwent clinical breast examination, ultrasound, SWE and ultrasound-guided core biopsy of the breast mass. Breast Imaging Reporting and Data System (BI-RAD) categories were assigned to breast masses. For qualitative and quantitative variables of SWE, cut-off values for differentiation between benign and malignant breast masses were estimated. Modified BIRADS' (up/downgrading of BIRADS category) was done for BI-RADS 3/4a masses by combining individual SWE parameters and ultrasound findings. Sensitivity, specificity, positive and negative predictive value of modified BI-RADS' and ultrasound BI-RADS were compared. RESULTS: A total of 119 women (mean age, 42.3±13.6 [SD] years; range: 13-87 years) with a single breast mass each were enrolled. Histopathologically, 57/119 (48%) breast masses were benign and 62 (52%) were malignant. On ultrasound, 42 breast masses were BI-RADS3 and 77 were BI-RADS 4 (4a, n=10; 4b, n=24; 4c, n=43) leading to 96.8% sensitivity and 70.2% specificity. On SWE, benign breast masses were oval/round, homogenous/reasonably homogenous, blue/green with lower elasticity values and malignant breast masses were irregular, inhomogeneous, red/orange with high elasticity values. On modified BI-RADS' using E-color and E-mean/E-max, specificity improved to 78.9% and 75.4% respectively. CONCLUSION: Addition of SWE to ultrasound improves characterization of BI-RADS 3 and 4a masses. E-max, E-mean and E-color are the most useful SWE parameters to differentiate between malignant and benign breast masses.


Assuntos
Doenças Mamárias/diagnóstico por imagem , Técnicas de Imagem por Elasticidade , Ultrassonografia Mamária , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto Jovem
3.
Diagn Interv Imaging ; 98(3): 253-260, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27692674

RESUMO

PURPOSE: To compare the diagnostic accuracy of contrast-enhanced ultrasound (CEUS) with that of multiphase computed tomography (CT) in the evaluation of tumor response to transarterial chemoembolization (TACE) of hepatocellular carcinoma (HCC). MATERIAL AND METHODS: Fifty patients (41 men, 9 women; mean age, 53 years±12.5 [SD]) with a total of 70 HCCs (mean size, 5cm±3 [SD]) were evaluated. Post-TACE therapeutic assessment of HCC was done at 4 weeks. Patients with TACE done earlier and reporting with suspicion for recurrence were also included. Patients with hepatic masses seen on ultrasound were enrolled and subjected to CEUS, multiphase CT and magnetic resonance imaging (MRI). Hyperenhancing area at the tumor site on arterial phase of CEUS/multiphase CT/MRI was termed as residual disease (RD), the patterns of which were described on CEUS. Diagnostic accuracies of CEUS and MPCT were compared to that of MRI that was used as the reference standard. RESULTS: CEUS detected RD in 43/70 HCCs (61%). RD had a heterogeneous pattern in 22/43 HCCs (51%). Sensitivities of CEUS and multiphase CT were 94% (34/36; 95% CI: 81-99%) and 50% (18/36; 95% CI: 33-67%) respectively. Significant difference in sensitivity was found between CEUS and multiphase CT (P=0.0001). CEUS and multiphase CT had 100% specificity (95% CI: 83-100%). CONCLUSION: CEUS is a useful technique for detecting RD in HCC after TACE. For long term surveillance, CEUS should be complemented with multiphase CT/MRI for a comprehensive evaluation.


Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/terapia , Neoplasia Residual/diagnóstico por imagem , Meios de Contraste , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X , Ultrassonografia
4.
Diagn Interv Imaging ; 96(11): 1169-75, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26292615

RESUMO

RATIONALE AND BACKGROUND: Transarterial chemoembolization (TACE) is the most frequently used palliative therapy for unresectable hepatocellular carcinoma (HCC). It is a safe and effective procedure with few major and minor complications. Rarely, biliary complications are also encountered following TACE. The goal of our study was to investigate the incidence and the presentation of biliary complications following TACE in patients with HCC. MATERIAL AND METHODS: In this retrospective study, data of patients with HCC who underwent TACE between June 2002 to December 2014 were obtained from the records. Their detailed information about the procedure of TACE, diagnosis of biliary complications and subsequent management details were reviewed. RESULT: One hundred and sixty-eight patients with HCC underwent 305 procedures of TACE. Of these, biliary complications of various severities developed in 6 (3.6%) patients leading to an incidence of 1.9% (6/305). Minimal intrahepatic biliary dilatation (IHBD) occurred in three, biliary stricture in one and intrahepatic biloma in two patients. Supportive management was undertaken for IHBD patients while percutaneous aspiration and naso-biliary drainage was performed for the infected bilomas. CONCLUSION: Biliary complications following TACE are infrequent. Diagnosis should be suspected clinically and confirmed with imaging. Treatment depends on the severity. Enforcing specific measures can minimize its frequency.


Assuntos
Doenças dos Ductos Biliares/etiologia , Ductos Biliares Intra-Hepáticos , Carcinoma Hepatocelular/terapia , Quimioembolização Terapêutica/efeitos adversos , Neoplasias Hepáticas/terapia , Adolescente , Adulto , Idoso , Artérias , Quimioembolização Terapêutica/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
5.
Aliment Pharmacol Ther ; 41(10): 961-71, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25809735

RESUMO

BACKGROUND: Frequency of hepatocellular carcinoma (HCC) in hepatic venous outflow tract obstruction (HVOTO) is unclear and risk factors in HVOTO associated with HCC are unknown. AIM: To assess the incidence of HCC and to identify risk factors for HCC in primary HVOTO. METHODS: In the consecutive primary HVOTO patients evaluated between 1989 to 2013, the incidence of HCC among HVOTO was assessed in a retrospective cohort study and identification of the risk factors for HCC in HVOTO patients done by a case-control study. RESULTS: Of the 421 HVOTO patients, 8 had HCC at presentation (prevalence 1.9%). Another 8 of the remaining 413 developed HCC during 2076.2 person-years follow-up (mean 5.03 + 4.65 years, range 0.08-20 years). The cumulative incidence of HCC was 3.5% (95% CI 1.28-9.2%) at 10 years. The case-control study included 16 HCC as cases and remaining 405 as controls. Controls were predominantly males (M:F - 230:175), mean age 29 ± 10.3 years. Cases were predominantly females with an older age of 36.2 ± 11.4 years (P < 0.01, OR = 1.06, CI 1.0-1.10%). Presence of cirrhosis (P < 0.001), combined inferior vena cava (IVC) and hepatic vein (HV) block (P < 0.03, OR = 5.58, CI 1.43-25.30%) and long-segment IVC block (P < 0.02, OR = 6.50, CI 1.32-32.0%) were significantly higher among cases than controls. CONCLUSIONS: Hepatic venous outflow tract obstruction is a risk factor for HCC. The cumulative incidence of HCC in HVOTO is low and progressively increases over time. Those with liver cirrhosis, combined IVC and HV block and long-segment IVC block are at risk to develop HCC and need active surveillance.


Assuntos
Síndrome de Budd-Chiari/complicações , Carcinoma Hepatocelular/etiologia , Neoplasias Hepáticas/etiologia , Adolescente , Adulto , Carcinoma Hepatocelular/epidemiologia , Carcinoma Hepatocelular/patologia , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Seguimentos , Humanos , Incidência , Neoplasias Hepáticas/epidemiologia , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Fatores de Risco , Veia Cava Inferior , Adulto Jovem
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