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1.
J Magn Reson Imaging ; 59(3): 1034-1042, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37272790

RESUMEN

BACKGROUND: The assessment of resectability after neoadjuvant chemotherapy of hepatoblastoma is dependent on Post-Treatment EXTENT of Disease (POSTTEXT) staging and its annotation factors P (portal venous involvement) and V (hepatic venous/inferior vena cava [IVC] involvement), but MR performance in assessing them remains unclear. PURPOSE: To assess the diagnostic performance of contrast-enhanced MR imaging for preoperative POSTTEXT staging and diagnosing vascular involvement in terms of annotation factors P and V in pediatric hepatoblastoma following neoadjuvant chemotherapy. STUDY TYPE: Retrospective. SUBJECTS: Thirty-five consecutive patients (17 males, median age, 24 months; age range, 6-98 months) with proven hepatoblastoma underwent preoperative MR imaging following neoadjuvant chemotherapy. FIELD STRENGTH/SEQUENCE: 3.0 T; T2-weighted imaging (T2WI), T2WI with fat suppression, diffusion weighted imaging, radial stack-of-the-star/Cartesian 3D Dixon T1-weighted gradient echo imaging. ASSESSMENT: Three radiologists independently assessed the POSTTEXT stages and annotation factors P and V based on the 2017 PRE/POSTTEXT system. The sensitivities and specificities were calculated for 1) diagnosing each POSTTEXT stage; 2) discrimination of stages III and IV (advanced) from those stages I and II (non-advanced) hepatoblastomas; and 3) annotation factors P and V. The combination of pathologic findings and surgical records served as the reference standard. STATISTICAL TESTS: Sensitivity, specificity, Fleiss kappa test. RESULTS: The sensitivity and specificity ranges for discriminating advanced from non-advanced hepatoblastomas were 73.3%-80.0% and 80.0%-90.0%, respectively. For annotation factor P, they were 66.7%-100.0% and 90.6%, respectively. For factor V, they were 75.0% and 67.7%-83.9%, respectively. There was excellent, substantial, and moderate agreement on POSTTEXT staging (Fleiss kappa = 0.82), factors P (Fleiss kappa = 0.64), and factors V (Fleiss kappa = 0.60), respectively. DATA CONCLUSION: MR POSTTEXT provides reliable discrimination between advanced and non-advanced tumors, and MR has moderate to excellent specificity at identifying portal venous and hepatic venous/IVC involvement. EVIDENCE LEVEL: 3 TECHNICAL EFFICACY: Stage 3.


Asunto(s)
Hepatoblastoma , Neoplasias Hepáticas , Masculino , Niño , Humanos , Preescolar , Lactante , Hepatoblastoma/tratamiento farmacológico , Hepatoblastoma/patología , Hepatoblastoma/cirugía , Terapia Neoadyuvante , Estudios Retrospectivos , Imagen por Resonancia Magnética/métodos , Venas Hepáticas , Sensibilidad y Especificidad , Neoplasias Hepáticas/patología , Estadificación de Neoplasias
2.
World J Surg Oncol ; 21(1): 239, 2023 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-37542314

RESUMEN

BACKGROUND: As digital medicine has exerted profound influences upon diagnosis and treatment of hepatobiliary diseases, our study aims to investigate the accuracy of three-dimensional visualization and evaluation (3DVE) system in assessing the resectability of hilar cholangiocarcinoma (hCCA), and explores its potential clinical value. MATERIALS AND METHODS: The discovery cohort, containing 111 patients from April 2013 to December 2019, was retrospectively included to determine resectability according to revised criteria for unresectability of hCCA. 3D visualization models were reconstructed to evaluate resectability parameters including biliary infiltration, vascular involvement, hepatic atrophy and metastasis. Evaluation accuracy were compared between contrast-enhanced CT and 3DVE. Logistic analysis was performed to identify independent risk factors of R0 resection. A new comprehensive 3DVE classification of hCCA based on factors influencing resectability was proposed to investigate its role in predicting R0 resection and prognosis. The main outcomes were also analyzed in cohort validation, including 34 patients from January 2020 to August 2022. RESULTS: 3DVE showed an accuracy rate of 91% (95%CI 83.6-95.4%) in preoperatively evaluating hCCA resectability, significantly higher than 81% (95%CI 72.8-87.7%) of that of CT (p = 0.03). By multivariable analysis, hepatic artery involvement in 3DVE was identified an independent risk factor for R1 or R2 resection (OR = 3.5, 95%CI 1.4,8.8, P < 0.01). New 3DVE hCCA classification was valuable in predicting patients' R0 resection rate (p < 0.001) and prognosis (p < 0.0001). The main outcomes were internally validated. CONCLUSIONS: 3DVE exhibited a better efficacy in evaluating hCCA resectability, compared with contrast-enhanced CT. Preoperative 3DVE demonstrated hepatic artery involvement was an independent risk factor for the absence of R0 margin. 3DVE classification of hCCA was valuable in clinical practice.


Asunto(s)
Neoplasias de los Conductos Biliares , Colangiocarcinoma , Tumor de Klatskin , Humanos , Tumor de Klatskin/diagnóstico por imagen , Tumor de Klatskin/cirugía , Tumor de Klatskin/patología , Colangiocarcinoma/diagnóstico por imagen , Colangiocarcinoma/cirugía , Colangiocarcinoma/patología , Imagenología Tridimensional , Estudios Retrospectivos , Neoplasias de los Conductos Biliares/diagnóstico por imagen , Neoplasias de los Conductos Biliares/cirugía , Neoplasias de los Conductos Biliares/patología , Conductos Biliares Intrahepáticos/diagnóstico por imagen , Conductos Biliares Intrahepáticos/cirugía , Conductos Biliares Intrahepáticos/patología
3.
Hepatobiliary Pancreat Dis Int ; 15(4): 391-8, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27498579

RESUMEN

BACKGROUND: Pyogenic hepatic abscess may mimic primary or secondary carcinoma of the liver on contrast-enhanced computed tomography (CECT). The present study was to explore the usefulness of the analysis of multislice-based texture acquired from CECT in the differentiation between pyogenic hepatic abscesses and malignant mimickers. METHODS: This retrospective study included 25 abscesses in 20 patients and 33 tumors in 26 subjects who underwent CECT. To make comparison, we also enrolled 19 patients with hepatic single simple cyst. The images from CECT were analyzed using a Laplacian of Gaussian band-pass filter (5 filter levels with sigma weighting ranging from 1.0 to 2.5). We also quantified the uniformity, entropy, kurtosis and skewness of the multislice-based texture at different sigma weightings. Statistical significance for these parameters was tested with one-way ANOVA followed by Tukey honestly significant difference (HSD) test. Diagnostic performance was evaluated using the receiver operating characteristic (ROC) curve analysis. RESULTS: There were significant differences in entropy and uniformity at all sigma weightings (P<0.001) among hepatic abscesses, malignant mimickers and simple cysts. The significant difference in kurtosis and skewness was shown at sigma 1.8 and 2.0 weightings (P=0.002-0.006). Tukey HSD test showed that the abscesses had a significantly higher entropy and lower uniformity compared with malignant mimickers (P=0.000-0.004). Entropy (at a sigma 2.0 weighting) had the largest area under the ROC curve (0.888) in differentiating abscesses from malignant mimickers, with a sensitivity of 81.8% and a specificity of 88.0% when the cutoff value was set to 3.64. CONCLUSION: Multislice-based texture analysis may be useful for differentiating pyogenic hepatic abscesses from malignant mimickers.


Asunto(s)
Medios de Contraste/administración & dosificación , Yohexol/análogos & derivados , Absceso Piógeno Hepático/diagnóstico por imagen , Neoplasias Hepáticas/diagnóstico por imagen , Tomografía Computarizada Multidetector/métodos , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Anciano , Anciano de 80 o más Años , Área Bajo la Curva , Diagnóstico Diferencial , Femenino , Humanos , Yohexol/administración & dosificación , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Valor Predictivo de las Pruebas , Curva ROC , Reproducibilidad de los Resultados , Estudios Retrospectivos
4.
J Vasc Interv Radiol ; 25(5): 739-46, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24745904

RESUMEN

PURPOSE: To prospectively determine the feasibility of flat-detector (FD) computed tomography (CT) perfusion to measure hepatic blood volume (BV) in the angiography suite in patients with hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Twenty patients with HCC were investigated with conventional multislice and FD CT perfusion. CT perfusion was carried out on a multislice CT scanner, and FD CT perfusion was performed on a C-arm angiographic system, before transarterial chemoembolization procedures. BV values of conventional and FD CT perfusion were measured within tumors and liver parenchyma. The arterial perfusion portion of CT perfusion BV was extracted from CT perfusion BV by multiplying it by a hepatic perfusion index. Relative values (RVs) for CT perfusion arterial BV and FD CT perfusion BV (FD BV) were defined by dividing BV of tumor by BV of parenchyma. Relationships between BV and RV values of these two techniques were analyzed. RESULTS: In all patients, both perfusion procedures were technically successful, and all 33 HCCs larger than 10 mm were identified with both imaging methods. There were strong correlations between the absolute values of FD BV and CT perfusion arterial BV (tumor, r = 0.903; parenchyma, r = 0.920; both P < .001). Bland-Altman analysis showed a mean difference of -0.15 ± 0.24 between RVs for CT perfusion arterial BV and FD BV. CONCLUSIONS: The feasibility of FD CT perfusion to assess BV values of liver tumor and surrounding parenchyma in the angiographic suite was demonstrated.


Asunto(s)
Angiografía/métodos , Volumen Sanguíneo , Carcinoma Hepatocelular/fisiopatología , Neoplasias Hepáticas/fisiopatología , Neovascularización Patológica/fisiopatología , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Anciano de 80 o más Años , Angiografía/instrumentación , Velocidad del Flujo Sanguíneo , Determinación del Volumen Sanguíneo/instrumentación , Determinación del Volumen Sanguíneo/métodos , Carcinoma Hepatocelular/diagnóstico por imagen , Estudios de Factibilidad , Femenino , Humanos , Circulación Hepática , Neoplasias Hepáticas/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Neovascularización Patológica/diagnóstico por imagen , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Tomografía Computarizada por Rayos X/instrumentación , Adulto Joven
5.
Radiographics ; 33(5): 1419-33, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24025933

RESUMEN

A multilocular cystic hepatic lesion detected at computed tomography (CT) and magnetic resonance (MR) imaging is a common but nonspecific radiologic finding that can cause potential challenges for differential diagnosis. This imaging pattern may be observed in a wide spectrum of common and uncommon neoplastic or nonneoplastic entities. Neoplastic lesions include cystadenoma, cystadenocarcinoma, hepatocellular carcinoma (HCC), metastases, mesenchymal hamartoma, and inflammatory myofibroblastic tumor. Nonneoplastic lesions include hepatic abscess, echinococcal cyst, intrahepatic hematoma, and biloma. The multiple coalescent cysts seen in polycystic liver disease may exhibit an imaging pattern similar to that of a multilocular cystic lesion. Mural nodularity, irregular thickness of the septa, ragged inner surface, and typical enhancement pattern in the solid portion of the lesion are often indicative of malignancy, although multilocular primary or secondary malignant tumors are uncommon. Recognition of the more common necrosis or cystic change of HCC and metastases induced by locoregional or systemic treatment also is important. The nonenhanced cystic component may be composed of different types of fluids (eg, serous, mucinous, proteinaceous, hemorrhagic, bilious, or mixed) or spontaneous or treatment-related necrosis, whereas the septa may be formed by a wide range of tissues depending on the lesion type. An understanding of the CT and MR imaging findings of these lesions and their respective pathologic correlation aids in accurate diagnosis.


Asunto(s)
Quistes/diagnóstico , Hepatitis/diagnóstico , Hepatopatías/diagnóstico , Neoplasias Hepáticas/diagnóstico , Hígado/diagnóstico por imagen , Hígado/patología , Imagen por Resonancia Magnética/métodos , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estadística como Asunto
6.
Eur Radiol ; 22(10): 2178-85, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22622347

RESUMEN

OBJECTIVES: To assess the feasibility and value of dual-energy spectral computed tomography (DESCT) imaging for differentiating neoplastic from bland macroscopic portal vein (PV) thrombi. METHODS: Computed tomography (CT) images of 44 patients with macroscopic PV thrombus (bland group, n = 16; neoplastic group, n = 28) were reviewed. Iodine-based material decomposition images in the portal venous phase were reconstructed to compare the iodine indices between groups, including thrombus iodine density (I (T)), thrombus-aorta iodine density ratio (I (T)/I (A)), and thrombus-PV iodine density ratio (I (T)/I (P)). Differential diagnostic performances of DESCT were calculated in the subgroup of 21 patients with histopathological evidence (bland group, n = 12; neoplastic group, n = 9). RESULTS: The iodine indices of the neoplastic group were significantly higher than those in the bland group (P < 0.001). A threshold I (T) of 1.14 mg/mL, I (T)/I (A) of 0.17, and I (T)/I (P) of 0.17 in the portal venous phase yielded 100 %, 88.9 %, and 100 % sensitivity, and 91.7 %, 91.7 %, and 83.3 % specificity, respectively, in differentiating neoplastic from bland PV thrombi. CONCLUSIONS: DESCT imaging with quantification of thrombus iodine density in the portal venous phase appears to be a promising new method for distinguishing neoplastic from bland macroscopic PV thrombi. KEY POINTS: • Differentiating the nature of portal vein thrombus is of great clinical significance. • Iodine-based material decomposition imaging reflects iodine distribution after contrast media administration. • Dual-energy CT with iodine quantification can distinguish bland from neoplastic PV thrombi.


Asunto(s)
Células Neoplásicas Circulantes , Vena Porta , Trombosis/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Adulto , Anciano , Anciano de 80 o más Años , Diagnóstico Diferencial , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Tomografía Computarizada por Rayos X/métodos , Adulto Joven
7.
Hepatobiliary Pancreat Dis Int ; 11(1): 74-80, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22251473

RESUMEN

BACKGROUND: Portal hyperperfusion in the small-for-size (SFS) liver can threaten survival of rabbits. Therefore, it is important to understand the hemodynamic changes in the SFS liver. METHODS: Twenty rabbits were divided into two groups: a control group and a modulation group. The control group underwent an extended hepatectomy. The modulation group underwent the same procedure plus splenectomy to reduce portal blood flow. CT perfusion examinations were performed on all rabbits before and after operation. Perfusion parameter values, especially portal vein perfusion (PVP), were analyzed. RESULTS: PVP in the modulation group was lower than in the control group after operation (P=0.002). In the control group, postoperative PVP increased by 193.7+/-55.1% compared with preoperative PVP. A weak correlation was found between the increased percentage of PVP and resected liver-to-body weight ratio (RLBWR) (r=0.465, P=0.033). In the modulation group, postoperative PVP increased by 101.4+/-32.5%. No correlation was found between the increased percentage of PVP and RLBWR (r=0.167, P=0.644). Correlations were found between PVP and serum alanine aminotransferase, aspartate aminotransferase, and total bilirubin after surgery (P<0.05). CONCLUSION: We successfully evaluated the characteristics of hemodynamic changes as well as the effects of splenectomy in the SFS liver in rabbits by the CT technique.


Asunto(s)
Hemodinámica , Hepatectomía/efectos adversos , Circulación Hepática , Imagen de Perfusión/métodos , Vena Porta/diagnóstico por imagen , Vena Porta/fisiopatología , Complicaciones Posoperatorias/diagnóstico por imagen , Complicaciones Posoperatorias/fisiopatología , Tomografía Computarizada por Rayos X , Alanina Transaminasa/sangre , Animales , Aspartato Aminotransferasas/sangre , Bilirrubina/sangre , Biomarcadores/sangre , Pruebas de Función Hepática , Masculino , Complicaciones Posoperatorias/sangre , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/prevención & control , Conejos , Esplenectomía
8.
Zhen Ci Yan Jiu ; 47(4): 349-53, 2022 Apr 25.
Artículo en Zh | MEDLINE | ID: mdl-35486015

RESUMEN

OBJECTIVE: To observe the effect of thunder-fire moxibustion combined with meibomian gland massage in improving meibomian gland dysfunction (MGD) and explore its mechanism. METHODS: Seventy-two MGD patients with 144 eyes in the Jinhua Hospital of Traditional Chinese Medicine from February 2019 to January 2021 were selected and randomly divided into an experimental group (n=36,72 eyes) and a control group (n=36, 72 eyes). Patients in the control group received 0.1% fluo-rometholone eye drops and 0.1% sodium hyaluronate eye drops, 1-2 drops per time, four times per day, and the meibomian glands were massaged once per day. Patients in the experimental group received additional thunder-fire moxibustion on the basis of the treatment of the control group, 10 cones per time, once per day. One month after treatment, meibomian gland function was assessed, and the levels of interleukin-6 (IL-6) and prostaglandin E2(PGE2) in tears were detected. RESULTS: After treatment, the scores of Ocular Surface Disease Index, meibomian hyperemia, meibomian gland opening, meibomian gland loss, and meibomian gland secretion function were lower than those before treatment in the two groups, and the scores of the experimental group were lower than those of the control group (P<0.05). After treatment, the tear break-up time and tear meniscus height were higher than those before treatment in the two groups, which were higher in the experimental group than those in the control group (P<0.05). The post-treatment levels of IL-6 and PGE2 were lower than those before treatment in the two groups, and the levels in the experimental group were lower than those in the control group (P<0.05). CONCLUSION: Thunder-fire moxibustion combined with meibomian gland massage can significantly improve the function of the meibomian glands and lower the levels of IL-6 and PGE2 in tears.


Asunto(s)
Glándulas Tarsales , Moxibustión , Dinoprostona , Humanos , Interleucina-6 , Masaje , Soluciones Oftálmicas , Estudios Prospectivos
9.
Zhongguo Dang Dai Er Ke Za Zhi ; 13(10): 820-2, 2011 Oct.
Artículo en Zh | MEDLINE | ID: mdl-22000440

RESUMEN

OBJECTIVE: Clinical pathways are standardized, multidisciplinary, integrated management plans. This study aimed to evaluate the efficacy of clinical pathways in children with Rotavirus enteritis. METHODS: Seventy-one children with Rotavirus enteritis were treated according to the clinical pathways. Seventy-five children with Rotavirus enteritis who received routine therapy and nursing interventions served as the control group. The clinical efficacies were compared between the two groups. RESULTS: The average hospitalization duration was shortened, the hospitalization costs were reduced and the parents' satisfaction rate increased in the observed group compared with the control group (P<0.05). CONCLUSIONS: The use of clinical pathways may decrease the hospitalization duration and costs and improve the quality of nursing care and the parents' satisfaction rate in children with Rotavirus enteritis.


Asunto(s)
Vías Clínicas , Enteritis/terapia , Infecciones por Rotavirus/terapia , Femenino , Humanos , Lactante , Tiempo de Internación , Masculino , Satisfacción del Paciente
10.
Abdom Radiol (NY) ; 46(9): 4226-4237, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33914139

RESUMEN

Pancreatic ductal adenocarcinomas (PDACs) occasionally have atypical and uncommon imaging presentations that can present a diagnostic dilemma and result in false interpretation. This article aimed to illustrate these CT and MR imaging findings, including isoattenuating PDAC, coexisting acute pancreatitis, PDAC with a cystic feature, groove PDAC, diffuse PDAC, hypointensity on diffusion-weighted imaging (DWI), multifocal PDAC, intratumoral calcification, and extrapancreatic invasion with a barely discernable mass. A subset of PDACs with atypical features are occasionally encountered during routine clinical practice. Knowledge of and attention to these atypical and uncommon variable imaging features may allow radiologists to avoid misinterpretation and a delayed diagnosis.


Asunto(s)
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Pancreatitis , Enfermedad Aguda , Carcinoma Ductal Pancreático/diagnóstico por imagen , Medios de Contraste , Diagnóstico Diferencial , Humanos , Imagen por Resonancia Magnética , Neoplasias Pancreáticas/diagnóstico por imagen , Tomografía Computarizada por Rayos X
11.
Abdom Imaging ; 35(5): 522-7, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19669829

RESUMEN

BACKGROUND: To identify hemodynamic alterations in anterior segment of liver graft after living-donor liver transplantation (LDLT) using CT perfusion imaging. METHODS: Perfusion images of 19 recipients 4 weeks after LDLT without reconstruction of the middle hepatic vein (MHV) tributaries were retrospectively identified. According to major MHV tributaries diameter in the right lobe graft, recipients were divided into large (≥ 5 mm) and small size groups (<5 mm). Blood flow (BF), blood volume (BV), and mean transit time (MTT) of anterior and posterior segments were calculated. RESULTS: In large size group, significantly decreased BF (66.98 ± 15.79 mL/min/100 g, corresponded to 37.08%), BV (8.27 ± 2.29 mL/100 g, 41.71%), and increased MTT (11.79 ± 2.10 s, 23.71%) were detected in the anterior segment compared to the posterior segment. In small size group, compared to the posterior segment, BF, BV in the anterior segment decreased 19.12%, 18.48%, respectively, and MTT increased 6.78%, where decreased BF (86.40 ± 21.39 mL/min/100 g) and BV (11.50 ± 2.59 mL/min/100 g) reached statistical significance. Perfusion imbalance in large size group was more remarkable than those in small size group. CONCLUSIONS: CT liver perfusion imaging enabled quantification of hemodynamic alterations in right-lobe liver graft after LDLT. Compared to small ones, ligation of large MHV tributaries could bring about more marked perfusion imbalance between anterior and posterior segments.


Asunto(s)
Trasplante de Hígado/métodos , Hígado/irrigación sanguínea , Hígado/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Adulto , Análisis de Varianza , Velocidad del Flujo Sanguíneo , Volumen Sanguíneo , Estudios de Casos y Controles , Medios de Contraste/administración & dosificación , Femenino , Humanos , Yohexol/administración & dosificación , Yohexol/análogos & derivados , Hígado/cirugía , Donadores Vivos , Masculino , Persona de Mediana Edad , Interpretación de Imagen Radiográfica Asistida por Computador , Estudios Retrospectivos , Estadísticas no Paramétricas
12.
Zhonghua Yi Xue Za Zhi ; 90(15): 1054-6, 2010 Apr 20.
Artículo en Zh | MEDLINE | ID: mdl-20646527

RESUMEN

OBJECTIVE: To discuss the value of spiral CT in diagnosing infantile intestinal malrotation. METHODS: The spiral CT findings and clinical data of 23 cases of operatively-confirmed infantile intestinal malrotation were retrospectively analyzed. RESULTS: Twenty-three cases of infantile intestinal malrotation were all diagnosed by SCT and confirmed by surgery. The main findings were as follows: whirlpool or concentric circle sign in mesenteric root with midgut volvulus (n = 16); duodenum assumed as "Z" or olecranon spur sign (n = 18); inverted transposition or vertical arrangement of superior mesenteric artery and vein (n = 13); abnormal sign of ileocecal junction and colon in right lower quadrant (n = 23). CONCLUSION: Spiral CT scanning has an important value in the early diagnosis of infantile intestinal malrotation.


Asunto(s)
Vólvulo Intestinal/diagnóstico por imagen , Tomografía Computarizada Espiral , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Vólvulo Intestinal/congénito , Intestinos/anomalías , Masculino , Estudios Retrospectivos
13.
Materials (Basel) ; 13(11)2020 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-32517028

RESUMEN

Hysteresis of the actuators based on magnetostrictive materials influences the control performance of the application systems. It is of importance and significance to establish an effective hysteresis model for the magnetostrictive actuators for precision engineering. In this paper, based on the analysis of the Duhem model, a first-order inertial system with hysteresis characteristic under harmonic input is used to describe the hysteresis caused by the inertia of the magnetic domains of magnetostrictive materials. Shape function is employed to describe the pinning of domain walls, the interactions of different magnetic domains of magnetostrictive materials, and the saturation properties of the hysteresis. Specifically, under an architecture of "inertial system + shape function" (ISSF-Duhem model), firstly a new hysteresis model is proposed for magnetostrictive actuators. The formulation of the inertial system is constructed based on its general expression, which is capable of describing the hysteresis characteristics of magnetostrictive actuators. Then, the developed models with a Grompertz function-based shape function, a modified hyperbolic tangent function-based shape function employing an exponential function as an offset function, a one-sided dead-zone operator-based shape function are compared with each other, and further compared with the classic modified Prandtl-Ishlinskii model with a one-sided dead-zone operator. Sequentially, feasibility and capability of the proposed hysteresis model are verified and evaluated by describing and predicting the hysteresis characteristics of a commercial magnetostrictive actuator.

14.
Clin Transplant ; 23(5): 692-9, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19473203

RESUMEN

Hepatic hemodynamic changes in grafts after living donor liver transplantation (LDLT) are complicated. In this study, computed tomography (CT) perfusion parameter values, especially portal vein perfusion (PVP), was retrospectively analyzed in recipients both with and without small-for-size syndrome (SFSS). PVP was significantly higher in non-SFSS recipients on post-operative day (POD) 14 or 28 than in normal donors before donation (p < 0.001 and p = 0.008, respectively), but it significantly decreased between 14 and 28 days post-operatively (p = 0.007). There was a significant inverse correlation between graft-to-recipient spleen size ratio and PVP on POD 14 in non-SFSS group (r = -0.545, p = 0.002). Furthermore, PVP in the SFSS group was significantly greater than in the non-SFSS group on POD 14 (p = 0.042). In conclusion, we successfully evaluated normal hemodynamic changes in grafts without SFSS by CT perfusion examination. To our knowledge, this is the first study on hemodynamic changes of living donor liver grafts using CT technique.


Asunto(s)
Trasplante de Hígado , Hígado/irrigación sanguínea , Hígado/diagnóstico por imagen , Donadores Vivos , Tomografía Computarizada por Rayos X , Adulto , Anciano , Ensayo de Inmunoadsorción Enzimática , Femenino , Supervivencia de Injerto , Hemodinámica , Humanos , Masculino , Persona de Mediana Edad , Perfusión , Reacción en Cadena de la Polimerasa , Pronóstico , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
15.
Zhongguo Zhen Jiu ; 39(3): 267-70, 2019 Mar 12.
Artículo en Zh | MEDLINE | ID: mdl-30942013

RESUMEN

OBJECTIVE: To analyze the effects of intradermal needling for pain and tear film stability in patients after pterygium excision. METHODS: A total of 76 patients (98 affected eyes) with primary pterygium were randomly divided into an observation group (38 cases, 53 affected eyes) and a control group (38 cases, 45 affected eyes).In the control group, only pterygium resection was performed, in the observation group, intradermal needling after pterygium resection was applied at Cuanzhu (BL 2), Yuyao (EX-HN 4), Taiyang (EX-HN 5), Sibai (ST 2), Hegu (LI 4), removed after 24 h and changed three times a week. The pain level of 3 days after surgery, dry eye symptoms, the basic tear secretion test (Schirmer-Ⅰ), and the tear-break time (BUT) changes before surgery, 2 weeks after surgery and 4 weeks after surgery were compared between the two groups, and the clinical efficacy was evaluated. RESULTS: The pain level of 3 days after surgery in the observation group was significantly lower than that in the control group (P<0.05). The dry eye symptom scores at 2 weeks and 4 weeks after surgery in the two groups were significantly lower than those before surgery (all P<0.05), and the dry eye symptom scores in the observation group were significantly lower than those in the control group (both P<0.05). The Schirmer-Ⅰ test at 2 weeks and 4 weeks after surgery was significantly prolonged than that before surgery(all P<0.05), and the Schirmer-Ⅰ test in the observation group was significantly longer than that in the control group (both P<0.05). The BUT at 2 weeks and 4 weeks after surgery in the two groups was significantly longer than that before surgery (all P<0.05), and the BUT in the observation group was significantly longer than that in the control group (both P<0.05). The total effective rate in the observation group was 89.5% (34/38), which was higher than 71.1% (27/38) in the control group (P<0.05). CONCLUSION: Intradermal needling can effectively reduce the pain level of patients after pterygium resection, improve dry eye symptoms, promote the secretion of tears and improve the tear film stability.


Asunto(s)
Síndromes de Ojo Seco , Pterigion , Puntos de Acupuntura , Humanos , Dolor , Lágrimas
17.
J Neurol Sci ; 268(1-2): 60-4, 2008 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-18068726

RESUMEN

BACKGROUND: Studies were carried out to detect brain tissue damage in patients with vascular cognitive impairment (VCI) using diffusion tensor imaging (DTI) histogram analysis, and to determine the correlations between DTI histogram-derived measures and Mini-Mental State Examination (MMSE) scores. METHODS: Conventional MRI and DTI scans were performed on 19 patients with VCI, 19 age- and sex-matched post-stroke patients without cognitive impairment (stroke group) and 19 cognitively normal subjects (CN group). Histograms of the apparent diffusion coefficient (ADC) and fractional anisotropy (FA) of the whole brain were analyzed. RESULTS: Analysis showed that the patterns of the whole brain ADC and FA histograms of the VCI group differed from those of the stroke and CN groups. Compared with those of the two control groups, the mean FA value was significantly lower and the FA histogram peak height was higher in the VCI group. However, the patterns of the whole brain ADC and FA histograms in the stroke group were similar to those of the CN group, and there were no significant differences in any of the DTI histogram-derived measures between these two groups. The mean FA value, the FA histogram peak height, and the FA histogram peak location in VCI patients correlated with the MMSE scores. CONCLUSIONS: Our findings suggest that VCI leads to abnormal diffusion in brain tissue, and that DTI histogram-derived measures might be used to monitor the severity of cognitive impairment in this disease.


Asunto(s)
Mapeo Encefálico , Encéfalo/patología , Trastornos del Conocimiento/metabolismo , Trastornos del Conocimiento/patología , Imagen de Difusión por Resonancia Magnética/métodos , Anciano , Análisis de Varianza , Trastornos del Conocimiento/etiología , Femenino , Humanos , Masculino , Estudios Prospectivos , Estudios Retrospectivos , Enfermedades Vasculares/complicaciones , Enfermedades Vasculares/metabolismo , Enfermedades Vasculares/patología
18.
AJR Am J Roentgenol ; 191(1): 290-1, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18562761

RESUMEN

OBJECTIVE: The objective of this article is to explain an easy and effective approach for managing radiologic files in portable document format (PDF) using iTunes. CONCLUSION: PDF files are widely used as a standard file format for electronic publications as well as for medical online documents. Unfortunately, there is a lack of powerful software to manage numerous PDF documents. In this article, we explain how to use the hidden function of iTunes (Apple Computer) to manage PDF documents as easily as managing music files.


Asunto(s)
Sistemas de Administración de Bases de Datos , Procesamiento Automatizado de Datos/métodos , Almacenamiento y Recuperación de la Información/métodos , Sistemas de Información Radiológica , Programas Informáticos
19.
Sci Rep ; 7(1): 2355, 2017 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-28539652

RESUMEN

As a newly identified factor in calcium-activated chloride channel, ANO1 participates in various physiological processes like proliferation and differentiation, and expresses in human cardiac fibroblasts. In this experiment, we investigated the function of ANO1 in cardiac fibrosis after myocardial infraction (MI) with methods of Western blotting, Quantitative real-time PCR (qRT-PCR), metabolic reduction of 3-(4,5-dimethylthiozol-2-yl)-2, 5-diphenyltetrazo-lium bromide (MTT), immunofluorescence and confocal imaging, and Masson's trichrome staining. The results showed that the expression of ANO1 significantly increased in neonatal rats' cardiac fibroblasts after hypoxia and in cardiac tissues after MI. After ANO1 over-expression, cardiac fibrosis was reduced in vitro and in vivo. Moreover, the expression of TGF-ß and p-smad3 declined after ANO1over-expression in cardiac fiborblasts. In conclusion, ANO1 inhibits cardiac fibrosis after MI via TGF-ß/smad3 pathway in rats.


Asunto(s)
Anoctamina-1/metabolismo , Infarto del Miocardio/metabolismo , Miocardio/metabolismo , Proteína smad3/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Animales , Animales Recién Nacidos , Anoctamina-1/genética , Hipoxia de la Célula , Células Cultivadas , Fibroblastos/metabolismo , Fibrosis , Expresión Génica , Masculino , Ratones Endogámicos C57BL , Infarto del Miocardio/genética , Miocardio/patología , Ratas Sprague-Dawley , Transducción de Señal
20.
Abdom Radiol (NY) ; 42(9): 2233-2242, 2017 09.
Artículo en Inglés | MEDLINE | ID: mdl-28401282

RESUMEN

PURPOSE: To determine reliable CT features to distinguish cancerous from inflammatory colorectal perforations. MATERIALS AND METHODS: A total of 43 patients with surgically and pathologically confirmed colorectal perforation caused by either colorectal cancer (n =27) or an inflammatory conditions (n = 16) were identified. Two radiologists independently assessed the contrast-enhanced CT features for locations of perforation, mural configurations, soft-tissue alterations, lymphadenopathy, and metastases. Intergroup comparisons for univariate analysis were performed using Fisher's exact test or chi-square test for categorical data and Mann-Whitney test for numeric data. Stepwise logistic regression analysis was conducted with features that were found significant under the univariate analysis. Interobserver agreement was assessed using intraclass correlation coefficient (ICC) and kappa test. RESULTS: Maximal mural thickness >1.39 cm (sensitivity, 100%; specificity, 68.75%), luminal mass or shoulder formation (sensitivity, 88.89%; specificity, 68.75%), absence of diverticula (sensitivity, 96.30%; specificity, 50.00%), irregular mural thickening (sensitivity, 92.59%; specificity, 81.25%), lymphadenopathy (sensitivity, 40.74%; specificity, 93.75%), and metastases (sensitivity, 25.93%; specificity, 100%) were significantly frequent in cancerous perforations. The maximal mural thickness (P = 0.0493, odds ratio = 439.83) and irregular mural thickening (P = 0.0343, odds ratio = 4.69) were identified as the highly distinguished identifiers. CONCLUSIONS: The CT manifestations of cancerous and inflammatory colorectal perforations overlap. Definitive diagnosis is not always possible with imaging alone. The maximal mural thickness >1.39 cm and irregular configuration of the thickened bowel wall were the two highly statistically significant CT features that may help order the difference between the two entities.


Asunto(s)
Neoplasias Colorrectales/complicaciones , Neoplasias Colorrectales/diagnóstico por imagen , Enfermedades Inflamatorias del Intestino/complicaciones , Enfermedades Inflamatorias del Intestino/diagnóstico por imagen , Perforación Intestinal/diagnóstico por imagen , Perforación Intestinal/etiología , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Anciano de 80 o más Años , Medios de Contraste , Diagnóstico Diferencial , Femenino , Humanos , Yopamidol , Metástasis Linfática/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Sensibilidad y Especificidad
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