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1.
World J Gastroenterol ; 18(31): 4136-44, 2012 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-22919245

RESUMO

AIM: To investigate the value of two-dimensional (2D) and three-dimensional (3D) double contrast-enhanced ultrasonography (DCUS) imaging for evaluation of gastric lesions. METHODS: 2D and 3D DCUS imaging with both oral and intravenous administrations of contrast agents was used to assess gastroscopiclly-confirmed gastric lesions in 46 patients with benign and malignant diseases. Initially, liquid-based ultrasound contrast agent (Xinzhang®) was given orally at dose of 500-600 mL for conventional ultrasound examination of the gastric lesions, and then a microbubble-based contrast agent (SonoVue) was injected intravenously at dose of 1.2-2.4 mL in bolus fashion to assess the perfusion pattern of the lesions using contrast imaging modes. The parameters derived from time-intensity curves including the arrival time (AT), time to peak (TTP), peak intensity (PI) and enhanced intensity (EI) were measured on the 2D DCUS imaging. 3D DCUS of the lesions was acquired to demonstrate the value of this imaging mode. RESULTS: There were 22 cases with benign lesions including chronic gastritis (n = 5), gastric ulcer (n = 9), gastric polyps (n = 3), gastric stromal tumors (n = 5), and 24 cases with malignant lesions including gastric cancer (n = 20), gastric cardia carcinoma (n = 3) and post-operative recurrent gastric cancer (n = 1) in the study. The oral contrast-enhanced ultrasonography (CEUS) imaging of the stomach clearly demonstrated the anatomy of the stomach and morphologic features of gastric lesions. With optimal scanning window and imaging display under oral CEUS, intravenous CEUS clearly showed the perfusion of gastric lesions with various characteristic manifestations. Both 2D and 3D DCUS images clearly demonstrated normal gastric wall as a three-layer structure, from the inside out, hyperechoic mucosa, hypoechoic muscularis and hyperechoic serosa, respectively. There were statistical significant differences of AT (8.68 ± 2.06 vs 10.43 ± 2.75, P = 0.017), PI (34.64 ± 6.63 vs 29.58 ± 8.22, P = 0.023) and EI (29.72 ± 6.69 vs 22.66 ± 7.01, P = 0.001) between malignant lesions and normal gastric wall. However, no differences of AT, PI and EI between benign lesions and normal gastric wall tissue were found. 3D DCUS could intuitively display morphological features and vascularities of the lesions with multiplanar and volume views. 3D DCUS imaging provided comprehensive information complementary to 2D imaging. The crater or wellhead appearances and feeding vessels as well as distorted nourishing vasculature of gastric carcinoma were better seen with 3D imaging than 2D imaging. CONCLUSION: DCUS imaging can simultaneously display the anatomic and perfusion features of gastric lesions. 3D DCUS can provide additional information to 2D DCUS for evaluation of gastric lesions.


Assuntos
Gastrite/diagnóstico por imagem , Neoplasias Gástricas/diagnóstico por imagem , Úlcera Gástrica/diagnóstico por imagem , Ultrassonografia/métodos , Administração Intravenosa , Administração Oral , Adulto , Idoso , Meios de Contraste/administração & dosagem , Feminino , Gastrite/patologia , Humanos , Aumento da Imagem/métodos , Masculino , Pessoa de Meia-Idade , Neoplasias Gástricas/patologia , Úlcera Gástrica/patologia
2.
Ultrasound Med Biol ; 35(5): 748-55, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19410132

RESUMO

To compare the feasibility of real-time myocardial contrast echocardiography (MCE) in rats with infusion and bolus administration of a second-generation ultrasound contrast agent BR1. B-mode real-time MCE was performed in 12 Sprague Dawley rats following the BR1 infusion or bolus injection. The myocardium signal intensity (SI) was plotted against time and was fitted to exponential functions. The plateau SI (A) and rate of SI increase (beta) for the infusion study and peak signal intensity (PSI) for the bolus study were obtained. (99m)Tc-Sestamibi and Evans blue were used to assess myocardial blood perfusion and to calculate the myocardium perfusion defect area ex vivo. High-quality real-time MCE images were successfully obtained using each method. At baseline, all LV segments showed even contrast distribution. Following left anterior descending coronary artery (LAD) ligation, significant perfusion defect was observed in LAD beds with a significantly decreased A* beta and PSI values compared with LCx beds (Infusion: A*beta (LAD): 5.42 +/- 1.57 dB, A*beta (LCx): 46.52 +/- 5.32 dB, p < 0.05; Bolus: PSI (LAD): 2.11 +/- 0.67 dB, PSI (LCx): 20.68 +/- 0.72 dB, p < 0.05), which was consistent with (99m)Tc-Sestamibi distribution findings. Myocardial perfusion defect areas, assessed by both methods, showed no differences and showed good correlation with Evans blue staining. ED frames were more favorable for imaging analysis. Both infusion and bolus administration of the contrast agent combined with real-time MCE technique can provide a reliable and noninvasive approach for myocardial perfusion assessment in rats and the infusion method was more suitable for quantitative analysis of myocardial blood flow.


Assuntos
Ecocardiografia/métodos , Fosfolipídeos/administração & dosagem , Hexafluoreto de Enxofre/administração & dosagem , Animais , Meios de Contraste/administração & dosagem , Circulação Coronária , Estudos de Viabilidade , Hemodinâmica/efeitos dos fármacos , Interpretação de Imagem Assistida por Computador/métodos , Infusões Intravenosas , Injeções Intravenosas , Ratos , Ratos Sprague-Dawley
3.
J Ultrasound Med ; 27(6): 867-74, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18499846

RESUMO

OBJECTIVE: The purpose of this study was to investigate the feasibility of percutaneous microwave coagulation therapy (PMCT) guided by contrast-enhanced ultrasonography (CEUS) for controlling active bleeding in rabbit livers. METHODS: Twenty actively bleeding rabbit liver models, produced with an 18-gauge semiautomatic biopsy needle and confirmed with CEUS, were randomly divided into 2 groups: a PMCT group (n=10, with a microwave antenna placed into the bleeding site under ultra-sonographic guidance and worked at 60 W for 30 seconds on average) and a control group (n=10, with the active bleeding site not treated). After therapy procedures were performed, lactated Ringer's solution resuscitation was then performed in both groups to maintain the mean arterial pressure at 70 mm Hg for 1 hour. The intraperitoneal blood loss, total resuscitation volume, mean arterial pressure, and hematocrit value were recorded. Macroscopic and microscopic examinations were performed at the end of the study. RESULTS: After PMCT, the former bleeding site appeared on CEUS as a round or an oval area devoid of contrast. The PMCT group had lower blood loss (30.4+/-7.2 versus 101.6 +/- 18.2 mL; P< .05) and a lower total resuscitation volume (56.5+/-10 versus 186+/-36.6 mL; P< .05) than the control group. The mean hematocrit value in the PMCT group was significantly higher than that in the control group (26%+/-4% versus 19%+/-4%; P< .05) at the end of the experiment. CONCLUSIONS: Contrast-enhanced ultrasonographically guided PMCT significantly decreased blood loss in a rabbit model of active liver bleeding. It provides a simple and quick method to control blood loss in liver injuries with active bleeding.


Assuntos
Hemorragia/terapia , Fígado/irrigação sanguínea , Micro-Ondas/uso terapêutico , Ultrassonografia de Intervenção , Animais , Meios de Contraste , Estudos de Viabilidade , Hemorragia/diagnóstico por imagem , Hemostasia , Fígado/diagnóstico por imagem , Fosfolipídeos , Coelhos , Hexafluoreto de Enxofre
4.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 24(6): 513-5, 2006 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-17334072

RESUMO

OBJECTIVE: To measure the spectral transmittance of Cerinate porcelain veneer and enamel in different color and different thickness. METHODS: Samples of Cerinate porcelain veneers were prepared in different thickness (0.50 mm, 0.75 mm, 1.00 mm) and different Vita shade (A1, A2, A3). Enamel samples in shade A2 were made with three thickness (0.50 mm, 0.75 mm, 1.00 mm). A spectrophotometer with spectra range (380-800 nm) was employed to measure the spectral transmittance. RESULTS: Spectral transmittance decreased with the increasing in the thickness of specimens and decreasing in the color darkness. The transmittance of Cerinate porcelain veneer material and enamel in the same color and same thickness hadn't significant difference. CONCLUSION: The key factor to spectral transmittance of porcelain veneer materials is veneer's thickness, and the color of the materials has also some influence on it. Cerinate porcelain veneers can properly recover the transparency of teeth.


Assuntos
Porcelana Dentária , Facetas Dentárias , Cerâmica , Cor , Esmalte Dentário , Humanos , Espectrofotometria
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