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1.
Abdom Radiol (NY) ; 49(8): 2639-2649, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38860996

RESUMEN

BACKGROUND: Hepatocellular carcinoma (HCC) is a unique cancer allowing tumor diagnosis with identification of definitive patterns of enhancement on contrast-enhanced imaging, avoiding invasive biopsy. However, it is still unclear to what extent Contrast-Enhanced Ultrasound (CEUS) is a clinically useful additional step when Computed tomography (CT) or Magnetic resonance imaging (MRI) are inconclusive. METHODS: A prospective international multicenter validation study for CEUS Liver Imaging Reporting and Data System (LI-RADS) was conducted between January 2018 and August 2021. 646 patients at risk for HCC with focal liver lesions were enrolled. CEUS was performed using an intravenous ultrasound contrast agent within 4 weeks of CT/MRI. Liver nodules were categorized based on LI-RADS (LR) criteria. Histology or one-year follow-up CT/MRI imaging results were used as the reference standard. The diagnostic performance of CEUS was evaluated for inconclusive CT/MRI scan in two scenarios for which the AASLD recommends repeat imaging or imaging follow-up: observations deemed non-characterizable (LR-NC) or with indeterminate probability of malignancy (LR-3). RESULTS: 75 observations on CT or MRI were categorized as LR-3 (n = 54) or LR-NC (n = 21) CEUS recategorization of such observations into a different LR category (namely, into one among LR-1, LR-2, LR-5, LR-M, or LR-TIV) resulted in management recommendation changes in 33.3% (25/75) and in all but one (96.0%, 24/25) observation, the new management recommendations were correct. CONCLUSION: CEUS LI-RADS resulted in management recommendations change in substantial number of liver observations with initial indeterminate CT/MRI characterization, identifying both non-malignant lesions and HCC, potentially accelerating the diagnostic process and alleviating the need for biopsy or follow-up imaging. CLINICALTRIALS: gov number, NCT03318380.


Asunto(s)
Carcinoma Hepatocelular , Medios de Contraste , Neoplasias Hepáticas , Imagen por Resonancia Magnética , Tomografía Computarizada por Rayos X , Ultrasonografía , Humanos , Neoplasias Hepáticas/diagnóstico por imagen , Carcinoma Hepatocelular/diagnóstico por imagen , Masculino , Imagen por Resonancia Magnética/métodos , Femenino , Tomografía Computarizada por Rayos X/métodos , Estudios Prospectivos , Ultrasonografía/métodos , Persona de Mediana Edad , Anciano , Adulto , Anciano de 80 o más Años
2.
Photochem Photobiol Sci ; 23(6): 1087-1115, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38763938

RESUMEN

The protection of Earth's stratospheric ozone (O3) is an ongoing process under the auspices of the universally ratified Montreal Protocol and its Amendments and adjustments. A critical part of this process is the assessment of the environmental issues related to changes in O3. The United Nations Environment Programme's Environmental Effects Assessment Panel provides annual scientific evaluations of some of the key issues arising in the recent collective knowledge base. This current update includes a comprehensive assessment of the incidence rates of skin cancer, cataract and other skin and eye diseases observed worldwide; the effects of UV radiation on tropospheric oxidants, and air and water quality; trends in breakdown products of fluorinated chemicals and recent information of their toxicity; and recent technological innovations of building materials for greater resistance to UV radiation. These issues span a wide range of topics, including both harmful and beneficial effects of exposure to UV radiation, and complex interactions with climate change. While the Montreal Protocol has succeeded in preventing large reductions in stratospheric O3, future changes may occur due to a number of natural and anthropogenic factors. Thus, frequent assessments of potential environmental impacts are essential to ensure that policies remain based on the best available scientific knowledge.


Asunto(s)
Ozono Estratosférico , Rayos Ultravioleta , Humanos , Ozono Estratosférico/análisis , Rayos Ultravioleta/efectos adversos , Ozono/química , Cambio Climático
3.
Photochem Photobiol Sci ; 21(3): 275-301, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35191005

RESUMEN

The Environmental Effects Assessment Panel of the Montreal Protocol under the United Nations Environment Programme evaluates effects on the environment and human health that arise from changes in the stratospheric ozone layer and concomitant variations in ultraviolet (UV) radiation at the Earth's surface. The current update is based on scientific advances that have accumulated since our last assessment (Photochem and Photobiol Sci 20(1):1-67, 2021). We also discuss how climate change affects stratospheric ozone depletion and ultraviolet radiation, and how stratospheric ozone depletion affects climate change. The resulting interlinking effects of stratospheric ozone depletion, UV radiation, and climate change are assessed in terms of air quality, carbon sinks, ecosystems, human health, and natural and synthetic materials. We further highlight potential impacts on the biosphere from extreme climate events that are occurring with increasing frequency as a consequence of climate change. These and other interactive effects are examined with respect to the benefits that the Montreal Protocol and its Amendments are providing to life on Earth by controlling the production of various substances that contribute to both stratospheric ozone depletion and climate change.


Asunto(s)
Pérdida de Ozono , Ozono , Cambio Climático , Ecosistema , Humanos , Ozono/química , Ozono Estratosférico , Rayos Ultravioleta
4.
Photochem Photobiol Sci ; 20(1): 1-67, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33721243

RESUMEN

This assessment by the Environmental Effects Assessment Panel (EEAP) of the United Nations Environment Programme (UNEP) provides the latest scientific update since our most recent comprehensive assessment (Photochemical and Photobiological Sciences, 2019, 18, 595-828). The interactive effects between the stratospheric ozone layer, solar ultraviolet (UV) radiation, and climate change are presented within the framework of the Montreal Protocol and the United Nations Sustainable Development Goals. We address how these global environmental changes affect the atmosphere and air quality; human health; terrestrial and aquatic ecosystems; biogeochemical cycles; and materials used in outdoor construction, solar energy technologies, and fabrics. In many cases, there is a growing influence from changes in seasonality and extreme events due to climate change. Additionally, we assess the transmission and environmental effects of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which is responsible for the COVID-19 pandemic, in the context of linkages with solar UV radiation and the Montreal Protocol.

5.
Photochem Photobiol Sci ; 19(5): 542-584, 2020 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-32364555

RESUMEN

This assessment, by the United Nations Environment Programme (UNEP) Environmental Effects Assessment Panel (EEAP), one of three Panels informing the Parties to the Montreal Protocol, provides an update, since our previous extensive assessment (Photochem. Photobiol. Sci., 2019, 18, 595-828), of recent findings of current and projected interactive environmental effects of ultraviolet (UV) radiation, stratospheric ozone, and climate change. These effects include those on human health, air quality, terrestrial and aquatic ecosystems, biogeochemical cycles, and materials used in construction and other services. The present update evaluates further evidence of the consequences of human activity on climate change that are altering the exposure of organisms and ecosystems to UV radiation. This in turn reveals the interactive effects of many climate change factors with UV radiation that have implications for the atmosphere, feedbacks, contaminant fate and transport, organismal responses, and many outdoor materials including plastics, wood, and fabrics. The universal ratification of the Montreal Protocol, signed by 197 countries, has led to the regulation and phase-out of chemicals that deplete the stratospheric ozone layer. Although this treaty has had unprecedented success in protecting the ozone layer, and hence all life on Earth from damaging UV radiation, it is also making a substantial contribution to reducing climate warming because many of the chemicals under this treaty are greenhouse gases.


Asunto(s)
Cambio Climático , Ozono Estratosférico , Rayos Ultravioleta , Salud Ambiental , Humanos , Microplásticos , Naciones Unidas
6.
Anaesthesia ; 74(5): 638-650, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30714123

RESUMEN

There has been an increase in the number of units providing anaesthesia for magnetic resonance imaging and the strength of magnetic resonance scanners, as well as the number of interventions and operations performed within the magnetic resonance environment. More devices and implants are now magnetic resonance imaging conditional, allowing scans to be undertaken in patients for whom this was previously not possible. There has also been a revision in terminology relating to magnetic resonance safety of devices. These guidelines have been put together by organisations who are involved in the pathways for patients needing magnetic resonance imaging. They reinforce the safety aspects of providing anaesthesia in the magnetic resonance environment, from the multidisciplinary decision making process, the seniority of anaesthetist accompanying the patient, to training in the recognition of hazards of anaesthesia in the magnetic resonance environment. For many anaesthetists this is an unfamiliar site to give anaesthesia, often in a remote site. Hospitals should develop and audit governance procedures to ensure that anaesthetists of all grades are competent to deliver anaesthesia safely in this area.


Asunto(s)
Anestesia/métodos , Imagen por Resonancia Magnética/métodos , Anestesia/efectos adversos , Anestesia/normas , Anestesiología/instrumentación , Competencia Clínica , Contraindicaciones de los Procedimientos , Humanos , Imagen por Resonancia Magnética/efectos adversos , Imagen por Resonancia Magnética/instrumentación , Imagen por Resonancia Magnética/normas , Ruido/efectos adversos , Salud Laboral , Seguridad del Paciente , Prótesis e Implantes , Reino Unido
7.
Photochem Photobiol Sci ; 17(2): 127-179, 2018 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-29404558

RESUMEN

The Environmental Effects Assessment Panel (EEAP) is one of three Panels of experts that inform the Parties to the Montreal Protocol. The EEAP focuses on the effects of UV radiation on human health, terrestrial and aquatic ecosystems, air quality, and materials, as well as on the interactive effects of UV radiation and global climate change. When considering the effects of climate change, it has become clear that processes resulting in changes in stratospheric ozone are more complex than previously held. Because of the Montreal Protocol, there are now indications of the beginnings of a recovery of stratospheric ozone, although the time required to reach levels like those before the 1960s is still uncertain, particularly as the effects of stratospheric ozone on climate change and vice versa, are not yet fully understood. Some regions will likely receive enhanced levels of UV radiation, while other areas will likely experience a reduction in UV radiation as ozone- and climate-driven changes affect the amounts of UV radiation reaching the Earth's surface. Like the other Panels, the EEAP produces detailed Quadrennial Reports every four years; the most recent was published as a series of seven papers in 2015 (Photochem. Photobiol. Sci., 2015, 14, 1-184). In the years in between, the EEAP produces less detailed and shorter Update Reports of recent and relevant scientific findings. The most recent of these was for 2016 (Photochem. Photobiol. Sci., 2017, 16, 107-145). The present 2017 Update Report assesses some of the highlights and new insights about the interactive nature of the direct and indirect effects of UV radiation, atmospheric processes, and climate change. A full 2018 Quadrennial Assessment, will be made available in 2018/2019.

8.
Sci Rep ; 6: 37507, 2016 11 29.
Artículo en Inglés | MEDLINE | ID: mdl-27897190

RESUMEN

We have designed a versatile and sensitive liquid chromatographic (LC) system, featuring a monolithic trap column and a very narrow (10 µm ID) fused silica open tubular liquid chromatography (OTLC) separation column functionalized with C18-groups, for separating a wide range of molecules (from small metabolites to intact proteins). Compared to today's capillary/nanoLC approaches, our system provides significantly enhanced sensitivity (up to several orders) with matching or improved separation efficiency, and highly repeatable chromatographic performance. The chemical properties of the trap column and the analytical column were fine-tuned to obtain practical sample loading capacities (above 2 µg), an earlier bottleneck of OTLC. Using the OTLC system (combined with Orbitrap mass spectrometry), we could perform targeted metabolomics of sub-µg amounts of exosomes with 25 attogram detection limit of a breast cancer-related hydroxylated cholesterol. With the same set-up, sensitive bottom-up proteomics (targeted and untargeted) was possible, and high-resolving intact protein analysis. In contrast to state-of-the-art packed columns, our platform performs chromatography with very little dilution and is "fit-for-all", well suited for comprehensive analysis of limited samples, and has potential as a tool for challenges in diagnostics.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Cromatografía Liquida/instrumentación , Hidroxicolesteroles/aislamiento & purificación , Péptidos/aislamiento & purificación , Proteómica/instrumentación , Espectrometría de Masas en Tándem/instrumentación , Animales , Proteína Axina/aislamiento & purificación , Neoplasias de la Mama/química , Neoplasias de la Mama/metabolismo , Cromatografía Liquida/métodos , Exosomas/química , Femenino , Humanos , Ratones , Proteómica/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Espectrometría de Masas en Tándem/métodos
9.
Ultraschall Med ; 34(1): 11-29, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23129518

RESUMEN

Initially, a set of guidelines for the use of ultrasound contrast agents was published in 2004 dealing only with liver applications. A second edition of the guidelines in 2008 reflected changes in the available contrast agents and updated the guidelines for the liver, as well as implementing some non-liver applications. Time has moved on, and the need for international guidelines on the use of CEUS in the liver has become apparent. The present document describes the third iteration of recommendations for the hepatic use of contrast enhanced ultrasound (CEUS) using contrast specific imaging techniques. This joint WFUMB-EFSUMB initiative has implicated experts from major leading ultrasound societies worldwide. These liver CEUS guidelines are simultaneously published in the official journals of both organizing federations (i.e., Ultrasound in Medicine and Biology for WFUMB and Ultraschall in der Medizin/European Journal of Ultrasound for EFSUMB). These guidelines and recommendations provide general advice on the use of all currently clinically available ultrasound contrast agents (UCA). They are intended to create standard protocols for the use and administration of UCA in liver applications on an international basis and improve the management of patients worldwide.


Asunto(s)
Carcinoma Hepatocelular/ultraestructura , Medios de Contraste/administración & dosificación , Aumento de la Imagen/métodos , Interpretación de Imagen Asistida por Computador/métodos , Hepatopatías/diagnóstico por imagen , Neoplasias Hepáticas/diagnóstico por imagen , Hígado/diagnóstico por imagen , Anafilaxia/inducido químicamente , Anafilaxia/mortalidad , Biopsia con Aguja/métodos , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/cirugía , Transformación Celular Neoplásica/patología , Contraindicaciones , Medios de Contraste/efectos adversos , Diagnóstico Diferencial , Hipersensibilidad a las Drogas/etiología , Hipersensibilidad a las Drogas/mortalidad , Interacciones Farmacológicas , Compuestos Férricos/efectos adversos , Fluorocarburos/efectos adversos , Humanos , Hierro/efectos adversos , Hígado/patología , Hígado/cirugía , Cirrosis Hepática/diagnóstico por imagen , Cirrosis Hepática/patología , Hepatopatías/patología , Hepatopatías/cirugía , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/secundario , Neoplasias Hepáticas/cirugía , Trasplante de Hígado/patología , Óxidos/efectos adversos , Fosfolípidos/efectos adversos , Factores de Riesgo , Hexafluoruro de Azufre/efectos adversos , Ultrasonografía Doppler/métodos , Ultrasonografía Intervencional/métodos
10.
Br J Cancer ; 103(3): 391-400, 2010 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-20588270

RESUMEN

BACKGROUND AND AIMS: The serum/plasma proteome was explored for biomarkers to improve the diagnostic ability of CA19-9 in pancreatic adenocarcinoma (PC). METHODS: A Training Set of serum samples from 20 resectable and 18 stage IV PC patients, 54 disease controls (DCs) and 68 healthy volunteers (HVs) were analysed by surface-enhanced laser desorption and ionisation time-of-flight mass spectrometry (SELDI-TOF MS). The resulting protein panel was validated on 40 resectable PC, 21 DC and 19 HV plasma samples (Validation-1 Set) and further by ELISA on 33 resectable PC, 28 DC and 18 HV serum samples (Validation-2 Set). Diagnostic panels were derived using binary logistic regression incorporating internal cross-validation followed by receiver operating characteristic (ROC) analysis. RESULTS: A seven-protein panel from the training set PC vs DC and from PC vs HV samples gave the ROC area under the curve (AUC) of 0.90 and 0.90 compared with 0.87 and 0.91 for CA19-9. The AUC was greater (0.97 and 0.99, P<0.05) when CA19-9 was added to the panels and confirmed on the validation-1 samples. A simplified panel of apolipoprotein C-I (ApoC-I), apolipoprotein A-II (ApoA-II) and CA19-9 was tested on the validation-2 set by ELISA, in which the ROC AUC was greater than that of CA19-9 alone for PC vs DC (0.90 vs 0.84) and for PC vs HV (0.96 vs 0.90). CONCLUSIONS: A simplified diagnostic panel of CA19-9, ApoC-I and ApoA-II improves the diagnostic ability of CA19-9 alone and may have clinical utility.


Asunto(s)
Adenocarcinoma/sangre , Apolipoproteína A-I/sangre , Apolipoproteína C-I/sangre , Biomarcadores de Tumor/sangre , Antígeno CA-19-9/sangre , Carcinoma Ductal Pancreático/sangre , Proteómica/métodos , Adulto , Anciano , Anciano de 80 o más Años , Alanina Transaminasa/sangre , Área Bajo la Curva , Aspartato Aminotransferasas/sangre , Carcinoma Ductal Pancreático/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Isoformas de Proteínas/sangre , Valores de Referencia , Análisis de Regresión , Reproducibilidad de los Resultados
12.
Vet Pathol ; 40(3): 332-4, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12724576

RESUMEN

Tumors of the perianal area of dogs are common and include multiple tumor types. Whereas perianal adenomas occur often, adenocarcinomas of the apocrine glands of the anal sac occur less frequently. A review of the literature revealed no reports of squamous cell carcinomas arising from the epithelial lining of the anal sac. Squamous cell carcinomas originating from the lining of the anal sac were diagnosed in five dogs. Microscopically, the tumors consisted of variably sized invasive nests and cords of epithelial cells displaying squamous differentiation. Four of the five dogs were euthanatized because of problems associated with local infiltration by the tumors. In the fifth dog, there was no evidence of tumor 7 months after surgical removal, but further follow up was not available.


Asunto(s)
Neoplasias de las Glándulas Anales/patología , Sacos Anales/patología , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/veterinaria , Enfermedades de los Perros/patología , Neoplasias de las Glándulas Anales/cirugía , Sacos Anales/cirugía , Animales , Carcinoma de Células Escamosas/cirugía , Enfermedades de los Perros/cirugía , Perros , Resultado Fatal , Femenino , Histocitoquímica/veterinaria , Masculino , Recurrencia Local de Neoplasia/patología
13.
Ann Hum Genet ; 67(Pt 1): 35-41, 2003 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-12556233

RESUMEN

We have previously reported strong evidence for linkage between IBD1 and Crohn's disease (CD) in Australian Crohn's disease families. Three risk alleles for Crohn's disease, (Arg702Trp (C/T), Gly908Arg (G/C) and 980fs981 (-/C), were recently identified in the CARD15/NOD2 gene on chromosome 16, implicating this as the IBD1 locus. Using a novel diagnostic PCR-RFLP, we have examined the frequency of these alleles in 205 multiplex IBD families, 107 sporadic Crohn's disease cases and 409 normal individuals. We demonstrate that the three risk alleles are more frequent in Crohn's disease, than in controls, with allelic frequencies of 0.11, 0.02 and 0.07 respectively. Heterozygosity for individual variants conferred a three-fold increase in risk for Crohn's disease while substantially higher risks were associated with being homozygous or compound heterozygous. Despite a significantly lower population allele frequency for the frameshift mutation than reported by other groups, we see a similar contribution by this allele to the risk of developing Crohn's disease. While the three risk alleles influence susceptibility to Crohn's disease in Australia, we show that these alleles do not fully explain the linkage evidence and suggest that there are very likely additional IBD1 susceptibility alleles yet to be described in Australian CD at the NOD2 locus. We also show a second linkage peak in Australian CD that provides some support for a second disease susceptibility locus on chromosome 16.


Asunto(s)
Proteínas Portadoras/genética , Enfermedad de Crohn/genética , Frecuencia de los Genes , Ligamiento Genético , Predisposición Genética a la Enfermedad , Péptidos y Proteínas de Señalización Intracelular , Alelos , Australia/epidemiología , Cromosomas Humanos Par 16 , Enfermedad de Crohn/epidemiología , Enfermedad de Crohn/etnología , Genotipo , Humanos , Mutación , Proteína Adaptadora de Señalización NOD2 , Factores de Riesgo
14.
Chest ; 120(5): 1709-22, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11713157

RESUMEN

STUDY OBJECTIVES: To determine the effectiveness of a cotinine-feedback, behaviorally based education intervention in reducing environmental tobacco smoke (ETS) exposure and health-care utilization of children with asthma. DESIGN: Randomized controlled trial of educational intervention vs usual care. SETTING: The pediatric pulmonary service of a regional pediatric hospital. PARTICIPANTS: ETS-exposed, Medicaid/Medi-Cal-eligible, predominantly minority children who were 3 to 12 years old and who were seen for asthma in the hospital's emergency, inpatient, and outpatient services departments (n = 87). INTERVENTION: Three nurse-led sessions employing behavior-changing strategies and basic asthma education and that incorporated repeated feedback on the child's urinary cotinine level. MEASUREMENTS: The primary measurements were the urinary cotinine/creatinine ratio (CCR) and the number of acute asthma medical visits. The secondary measurements were number of hospitalizations, smoking restrictions in home, amount smoked, reported exposures of children, and asthma control. RESULTS: The intervention was associated with a significantly lower odds ratio (OR) for more than one acute asthma medical visit in the follow-up year, after adjusting for baseline visits (total visits, 87; OR, 0.32; p = 0.03), and a comparably sized but nonsignificant OR for one or more hospitalization (OR, 0.34; p = 0.14). The follow-up CCR measurement and the determination of whether smoking was prohibited inside the home strongly favored the intervention group (n = 51) (mean difference in CCR adjusted for baseline, -0.38; p = 0.26; n = 51) (60; OR [for proportion of subjects prohibiting smoking], 0.24; p = 0.11; n = 60). CONCLUSIONS: This intervention significantly reduced asthma health-care utilization in ETS-exposed, low-income, minority children. Effects sizes for urine cotinine and proportion prohibiting smoking were moderate to large but not statistically significant, possibly the result of reduced precision due to the loss of patients to active follow-up. Improving ETS reduction interventions and understanding their mechanism of action on asthma outcomes requires further controlled trials that measure ETS exposure and behavioral and disease outcomes concurrently.


Asunto(s)
Asma/orina , Familia , Educación en Salud , Pobreza , Contaminación por Humo de Tabaco/prevención & control , Enfermedad Aguda , Asma/terapia , Niño , Preescolar , Cotinina/orina , Femenino , Servicios de Salud/estadística & datos numéricos , Humanos , Masculino , Contaminación por Humo de Tabaco/efectos adversos
15.
AJR Am J Roentgenol ; 177(3): 627-32, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11517059

RESUMEN

OBJECTIVE: Perianal infection arises in small intersphincteric anal glands predominantly located at the dentate line. Documentation of fluid collections and the relationship of inflammatory tracts to the sphincter mechanism is important for surgical treatment. Transanal sonography for assessment of perianal inflammatory disease is limited because placement of the rigid probe into the anal canal does not allow assessment of disease in the perineal region. The purpose of this study was to validate the use of transperineal sonography in men and both transvaginal and transperineal sonography in women for evaluation of perianal inflammatory disease. SUBJECTS AND METHODS: Fifty-four patients, 28 men and 26 women, were imaged with transperineal and a combination of transperineal and transvaginal sonography, respectively. All patients were examined in the supine lithotomy and left lateral position with a transvaginal 8-to 4-MHz probe or a linear 12- to 7-MHz transducer. All fluid collections, sinus tracts, and fistulas were described by their location in relation to the sphincter mechanism and perineum. RESULTS: Forty-six of 54 patients had perianal fistulas or sinus tracts: 33 transphincteric, seven intersphincteric, and six extrasphincteric. Fifteen patients had an associated abscess. In the eight remaining patients, there were two anovaginal fistulas, one rectovaginal fistula, one prolapsed internal hemorrhoid, two perianal complex masses, and two vascular perianal or perirectal inflammatory masses. Twenty-six patients underwent surgical procedures involving the anorectal canal or perirectal region, and of these, preoperative sonographic findings were confirmed in 22 (85%) of 26 patients. Three patients refused surgery, and six are awaiting surgery at this writing. Fifteen patients were treated conservatively. CONCLUSION: Transperineal and transvaginal sonography are accurate, painless, and cost-effective methods for documenting perianal fluid collections and fistulas or sinus tracts or both.


Asunto(s)
Endosonografía , Proctitis/diagnóstico por imagen , Fístula Rectal/diagnóstico por imagen , Absceso/diagnóstico por imagen , Adulto , Anciano , Colitis Ulcerosa/diagnóstico por imagen , Enfermedad de Crohn/diagnóstico por imagen , Fístula Cutánea/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fístula Rectovaginal/diagnóstico por imagen , Sensibilidad y Especificidad
16.
Semin Liver Dis ; 21(2): 147-59, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11436569

RESUMEN

Liver mass evaluation includes two essential elements--lesion detection and lesion characterization. Both of these are greatly improved on sonography with the addition of contrast agents and the use of specialized imaging techniques, particularly pulse inversion imaging. Ultrasound contrast agents are comprised of tiny microbubbles of gas that interact with the ultrasound beam producing an enhancement of the Doppler signal from blood. Pulse inversion imaging allows preferential detection of the signal from the microbubble agents with suppression of the signal from background tissue. Two imaging techniques include a low mechanical index (MI) nondestructive method to show lesional vascularity and a high MI destructive mode that produces disruption of the bubbles in a single frame. The latter allows for quantitative assessment of the relative enhancement of a lesion as compared with the adjacent liver parenchyma, which is a reflection of the relative vascular volumes. Vascular imaging has shown characteristic and reproducible features of common liver masses, including hemangioma, focal nodular hyperplasia, hepatocellular carcinoma, and liver metastases. Delayed postvascular enhancement of the normal liver, a phenomenon that is unique to certain classes of microbubble contrast agents, allows detection of more and smaller malignant lesions than on baseline.


Asunto(s)
Carcinoma Hepatocelular/diagnóstico por imagen , Hemangioma/diagnóstico por imagen , Aumento de la Imagen/métodos , Neoplasias Hepáticas/diagnóstico por imagen , Ultrasonografía Doppler/métodos , Carcinoma Hepatocelular/irrigación sanguínea , Carcinoma Hepatocelular/patología , Medios de Contraste/administración & dosificación , Gases , Hemangioma/irrigación sanguínea , Hemangioma/patología , Humanos , Neoplasias Hepáticas/irrigación sanguínea , Neoplasias Hepáticas/patología
19.
Ann Surg ; 233(3): 438-44, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11224634

RESUMEN

OBJECTIVE: To compare the effectiveness and safety of low-dose unfractionated heparin and a low-molecular-weight heparin as prophylaxis against venous thromboembolism after colorectal surgery. METHODS: In a multicenter, double-blind trial, patients undergoing resection of part or all of the colon or rectum were randomized to receive, by subcutaneous injection, either calcium heparin 5,000 units every 8 hours or enoxaparin 40 mg once daily (plus two additional saline injections). Deep vein thrombosis was assessed by routine bilateral contrast venography performed between postoperative day 5 and 9, or earlier if clinically suspected. RESULTS: Nine hundred thirty-six randomized patients completed the protocol and had an adequate outcome assessment. The venous thromboembolism rates were the same in both groups. There were no deaths from pulmonary embolism or bleeding complications. Although the proportion of all bleeding events in the enoxaparin group was significantly greater than in the low-dose heparin group, the rates of major bleeding and reoperation for bleeding were not significantly different. CONCLUSIONS: Both heparin 5,000 units subcutaneously every 8 hours and enoxaparin 40 mg subcutaneously once daily provide highly effective and safe prophylaxis for patients undergoing colorectal surgery. However, given the current differences in cost, prophylaxis with low-dose heparin remains the preferred method at present.


Asunto(s)
Anticoagulantes/uso terapéutico , Colectomía/métodos , Enoxaparina/uso terapéutico , Heparina/uso terapéutico , Recto/cirugía , Pérdida de Sangre Quirúrgica , Canadá/epidemiología , Método Doble Ciego , Femenino , Humanos , Inyecciones Subcutáneas , Complicaciones Intraoperatorias/epidemiología , Complicaciones Intraoperatorias/prevención & control , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/prevención & control , Hemorragia Posoperatoria/epidemiología , Estudios Prospectivos , Trombocitopenia/epidemiología , Trombocitopenia/etiología , Tromboembolia/epidemiología , Tromboembolia/prevención & control , Trombosis de la Vena/epidemiología , Trombosis de la Vena/prevención & control
20.
AJR Am J Roentgenol ; 176(3): 653-9, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11222199

RESUMEN

OBJECTIVE: Our purpose was to compare tissue harmonic imaging with conventional sonography of the biliary tract. SUBJECTS AND METHODS: Eighty patients with suspect biliary disease had conventional sonography and tissue harmonic imaging with an ATL 3000 or 5000 scanner in a 6-month interval. Final diagnoses included malignant biliary obstruction (n = 30), choledocholithiasis (n = 16), sclerosing cholangitis (n = 4), normal or nonobstructed ducts (n = 16), and miscellaneous conditions (n = 14). Similar images were taken with each technique in terms of projection, field of view, focal zone selection, and evidence of disease. Two separate observers blinded to patient data and technique reviewed and graded images individually for the appearance of the lumen of the bile ducts, the length of the visible duct, the appearance of the duct wall, the presence of any intraluminal masses, and the appearance of associated acoustic shadows. Images were graded from zero to 3, with 3 being the best. RESULTS: The median of the 546 tissue harmonic images was one grade higher than the median for the corresponding conventional images (p < 0.0001). Improvements with tissue harmonic imaging included better sharpness of the duct walls (p < 0.01), a clearer lumen (p < 0.0001), identification of a longer length of the common bile duct (p < 0.0001), and improved detection of intraluminal masses (p < 0.006). Acoustic shadows were better defined and blacker with tissue harmonic imaging (p < 0.007). CONCLUSION: Improvement in contrast and reduction of side lobe artifacts with tissue harmonic imaging enhance visualization of the biliary ducts. Tissue harmonic imaging is now our routine technique for bile duct examination.


Asunto(s)
Conductos Biliares/diagnóstico por imagen , Enfermedades de las Vías Biliares/diagnóstico por imagen , Artefactos , Femenino , Humanos , Aumento de la Imagen/métodos , Masculino , Persona de Mediana Edad , Ultrasonografía/métodos
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