RESUMEN
La prevalencia de enfermedad diverticular en Chile se estima en 28% y cada vez es más frecuente su presentación como diverticulitis complicada. Durante los últimos años ha surgido evidencia que ha hecho replantear el manejo de la diverticulitis aguda. Históricamen-te los antibióticos han sido pilar fundamental del tratamiento de la diverticulitis aguda, sin embargo, evidencia reciente muestra que pacientes con un episodio de diverticulitis aguda no complicada pueden ser tratados sin ellos. Con respecto al manejo quirúrgico, la cirugía de emergencia está indicada en peritonitis difusa, absceso no puncionable asociado a sepsis y fracaso de tratamiento; tanto la cirugía de Hartmann como resección y anastomosis primaria son opciones válidas según el escenario. La cirugía electiva debe indicarse caso a caso y se debe optar por abordaje laparoscópico dentro de lo posible. Al enfrentarse a pacientes inmunosuprimidos se debe ser más agresivo en el manejo. La indicación de colonoscopía posterior a un episodio de diverticulitis aguda se reserva para pacientes en los que se haya presentado como un episodio de diverticulitis complicada, en aquellos que corresponda realizar tamizaje para cáncer colorrectal y en los que presenten síntomas o signos sugerentes de neoplasia colorrectal.
The prevalence of diverticular disease in Chile is estimated to be 28%, and its presentation as complicated diverticulitis is becoming more common. Recently, new evidence has emerged, questioning the traditional management of acute diverticulitis. Historically, anti-biotics have been accepted as a cornerstone of the treatment for acute diverticulitis. However, current studies show that patients with documented non-complicated acute diverticulitis could be safely treated without them. Regarding surgical management, emergency surgery is indicated in those with diffuse peritonitis, percutaneously undrainable abscesses associated with sepsis and treatment failure. Both Hartmann's procedure and resection with primary anastomosis are acceptable choices according to different settings. Elective surgery should be indicated on a case-by-case basis, and a laparoscopic approach is the preferable option. When facing immunosu-ppressed patients, management should be more aggressive. Surveillance colonoscopy after an episode of acute diverticulitis is reserved for patients presenting with complicated diverticulitis, those with a formal indication of colorectal cancer screening and patients with symptoms or signs suggestive of colorectal malignancy.
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Spinal anesthesia is a very important and widely used technique nowadays. In order to obtain successful results and avoid complications, it is essential to perform it with the correct methods. The operator must be familiar with the procedure and prepare correctly for it, including material and drug selections which may vary according to the patient. Risk reduction is fundamental, and it is accomplished by carrying out the previously mentioned preparation and an adequate monitorization of the patient being intervened. Once this is in order, the patient must be positioned into being sited, or placed in supine or lateral position. The chosen approach depends mainly on the characteristics of anatomical repairs and may be medial, paramedian or a Taylor approach. The correct needle must be selected, and these are categorized mainly into those which cut or separate the dura's fibers. In this revision, the correct technique for performing spinal anesthesia is described, along with some of its most important variations such as sectorized anesthesia, continuous spinal anesthesia and combined epidural spinal anesthesia.
La anestesia espinal es una técnica ampliamente utilizada hoy en día. Para obtener resultados exitosos y evitar complicaciones, es fundamental una buena técnica a la hora de realizarla. Debe contarse con un buen conocimiento basal del método a utilizar y una preparación adecuada según el paciente, incluyendo en esto tanto los materiales como los fármacos de elección en cada caso. Es fundamental reducir los riesgos tanto locales como sistémicos del procedimiento, lo cual se logra con la preparación mencionada y una adecuada monitorización del paciente. Una vez listo esto, debe posicionarse al paciente de manera que quede sentado, en decúbito lateral o decúbito prono. El abordaje es elegido principalmente según los reparos anatómicos de cada caso particular y puede ser medio, paramediano o de Taylor. Se debe seleccionar una aguja adecuada, las cuales se dividen principalmente entre aquellas que cortan y aquellas que separan las fibras de la duramadre. En esta revisión se expone la técnica adecuada para realizar el procedimiento de anestesia espinal, junto con algunas de sus variaciones principales como lo son la anestesia sectorizada, la anestesia espinal continua y la anestesia combinada espinal epidural.
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Humanos , Anestesia Raquidea/métodosRESUMEN
Spinal anesthesia is a widely used technique in medical practice nowadays. Generally, nervous blockage is determined by three main factors. The first of them is the distribution of the local anesthetic in the cerebrospinal fluid (CSF), which can be affected by numerous factors, the most important of them being CSF volume. The second is absorption, which is greatest at the sites with higher drug concentration: this is the result of the accessibility, lipidic content and vascular irrigation of each area. The last of these factors is elimination, mediated mainly by the irrigation of the different compartments, and whose order differs from the mirror image of the onset's action order. The previously mentioned elements are the main sources of variation for the time needed to achieve desired effects, order in which fibers are affected and differential blockage. This text describes the principal mechanisms through which spinal anesthesia works, and the factors which can result in variations of its results.
La anestesia espinal es una técnica ampliamente utilizada en la práctica clínica. Por lo general, el bloqueo nervioso está determinado por tres factores principales. El primero es la distribución del anestésico local en el líquido cefalorraquídeo (LCR), que a su vez se ve afectado por una gran variedad de factores, destacando entre estos el volumen de LCR. El segundo es la absorción, la cual es mayor en los sitios en donde la concentración del fármaco también lo es: para esto afecta la accesibilidad, el contenido lipídico y la irrigación vascular de cada zona. El último factor es la eliminación, mediada principalmente por la irrigación de los distintos compartimentos, y cuyo orden es distinto a la imagen especular del inicio de acción. Los factores mencionados son los principales determinantes de los tiempos de demora de los bloqueos, el orden en el que se logra su acción en las distintas fibras y el bloqueo diferencial. Este texto pretende describir los principales mecanismos de acción mediante los cuales actúa la anestesia espinal y los factores que pueden determinar diferencias en los resultados de esta.
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Humanos , Anestesia Raquidea/métodos , Anestésicos Locales/farmacocinéticaRESUMEN
No disponible
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Humanos , Síndrome de Deleción 22q11/epidemiología , Síndrome de Deleción 22q11/genética , Trastorno por Déficit de Atención con Hiperactividad/genética , Trastornos Psicóticos/genética , Trastornos Neurocognitivos/genética , Psicopatología/métodos , Psicopatología/estadística & datos numéricos , Afecto , Escalas de Valoración Psiquiátrica , Neuropsiquiatría/métodosRESUMEN
INTRODUCTION: The 22q11.2 deletion syndrome is a genetic disorder with variable clinical manifestations. It affects one out of 5950 neonates and has an autosomal dominant inheritance pattern. The aim of this article is to review its psychiatric manifestations and any underlying genetic alterations. METHODS: We reviewed the scientific literature available as of October 2014 in the LILACS and Medline databases. RESULTS: Sixty per cent of these patients fulfilled diagnostic criteria for a mental disorder at some point in their lives, referring to psychotic disorders, attention deficit hyperactivity disorder, mood disorders, anxiety disorders, and autism spectrum disorders. Specific genes, such as COMT and PRODH, have been linked to these psychiatric manifestations. CONCLUSIONS: It is necessary to raise awareness among all health care professionals so that they understand the relevance of these manifestations, are able to anticipate them, and can provide appropriate information to patients and family members.
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Comorbilidad , Síndrome de DiGeorge/complicaciones , Síndrome de DiGeorge/genética , Trastornos Mentales/epidemiología , HumanosRESUMEN
The EORTC Quality of Life Group has just completed the final phase (field-testing and validation) of an international project to develop a stand-alone measure of spiritual well-being (SWB) for palliative cancer patients. Participants (n = 451)-from 14 countries on four continents; 54% female; 188 Christian; 50 Muslim; 156 with no religion-completed a provisional 36-item measure of SWB plus the EORTC QLQ-C15-PAL (PAL), then took part in a structured debriefing interview. All items showed good score distribution across response categories. We assessed scale structure using principal component analysis and Rasch analysis, and explored construct validity, and convergent/divergent validity with the PAL. Twenty-two items in four scoring scales (Relationship with Self, Relationships with Others, Relationship with Someone or Something Greater, and Existential) explained 53% of the variance. The measure also includes a global SWB item and nine other items. Scores on the PAL global quality-of-life item and Emotional Functioning scale weakly-moderately correlated with scores on the global SWB item and two of the four SWB scales. This new validated 32-item SWB measure addresses a distinct aspect of quality-of-life, and is now available for use in research and clinical practice, with a role as both a measurement and an intervention tool.
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Cristianismo , Islamismo , Neoplasias/terapia , Cuidados Paliativos , Religión y Medicina , Espiritualidad , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Emociones , Femenino , Humanos , Relaciones Interpersonales , Masculino , Persona de Mediana Edad , Neoplasias/psicología , Calidad de Vida , Reproducibilidad de los Resultados , Encuestas y Cuestionarios , Adulto JovenRESUMEN
Background: Quality of Life (QOL) assessment may evaluate the impact of diseases and their treatment on the overall well-being of patients. Aim: To assess QOL in Chilean breast cancer survivors. Patients and Methods: Ninety one female breast cancer patients aged 60 ± 10 years, who finished their oncologic treatment at least a year prior to the assessment, who were disease free and in medical follow-up were included in the study. They completed the European Organization for Research and Treatment of Cancer (EORTC) QLQ-C30 core questionnaire and the breast cancer module QLQ-BR23. Results: Forty eight percent of respondents were long term survivors (more than five years). Global QOL scores were high (73.6 ± 18.2), emotional scale had the lowest scores in QLQ-C30 functional scales (72.1). Symptoms with the highest scores were: Insomnia (= 21.2), pain (= 20.8), and fatigue (= 19.1). Body image, sexual function, and concern about the future were the most relevant problems. Body image was superior in patients with breast-conserving surgery (p = 0.008), and cognitive function was better in patients in early disease stage (p = 0.03) and in those with more than five years of survival (p = 0.04). Conclusions: Even when global QOL scores were high, some symptoms were prevalent. Awareness about these problems and symptoms should improve their diagnosis and treatment.
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Humanos , Femenino , Persona de Mediana Edad , Calidad de Vida/psicología , Imagen Corporal/psicología , Neoplasias de la Mama/psicología , Factores Socioeconómicos , Neoplasias de la Mama/cirugía , Mastectomía Segmentaria/psicología , Análisis de Supervivencia , Chile , Estudios TransversalesRESUMEN
BACKGROUND: Quality of Life (QOL) assessment may evaluate the impact of diseases and their treatment on the overall well-being of patients. AIM: To assess QOL in Chilean breast cancer survivors. PATIENTS AND METHODS: Ninety one female breast cancer patients aged 60 ± 10 years, who finished their oncologic treatment at least a year prior to the assessment, who were disease free and in medical follow-up were included in the study. They completed the European Organization for Research and Treatment of Cancer (EORTC) QLQ-C30 core questionnaire and the breast cancer module QLQ-BR23. RESULTS: Forty eight percent of respondents were long term survivors (more than five years). Global QOL scores were high (73.6 ± 18.2), emotional scale had the lowest scores in QLQ-C30 functional scales (72.1). Symptoms with the highest scores were: Insomnia (= 21.2), pain (= 20.8), and fatigue (= 19.1). Body image, sexual function, and concern about the future were the most relevant problems. Body image was superior in patients with breast-conserving surgery (p = 0.008), and cognitive function was better in patients in early disease stage (p = 0.03) and in those with more than five years of survival (p = 0.04). CONCLUSIONS: Even when global QOL scores were high, some symptoms were prevalent. Awareness about these problems and symptoms should improve their diagnosis and treatment.
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Imagen Corporal/psicología , Neoplasias de la Mama/psicología , Calidad de Vida/psicología , Neoplasias de la Mama/cirugía , Chile , Estudios Transversales , Femenino , Humanos , Mastectomía Segmentaria/psicología , Persona de Mediana Edad , Factores Socioeconómicos , Análisis de SupervivenciaRESUMEN
BACKGROUND: Quality of Life assessment in oncologic patients evaluates the impact and sequels of the disease ana the adverse effects of available treatments. AIM: To validate in Chile the breast cancer specific-questionnaire (BR23) developed by the European Organization for Research and Treatment of Cancer (EORTC). PATIENTS AND METHODS: After performing a linguistic validation of the BR23 according to EORTC instructions, its psychometric properties were tested in 103 patients with breast cancer whose ages ranged from 34 to 83 years. Internal consistency of the scales was assessed using the Cronbach's alpha coefficient. The test-retest correlations of each scale (n = 83) were evaluated. The correlation of BR23 scales with SF36 version 2 and C30 version 3.0 scales was also assessed. The sensitivity and specificity of the instrument were analyzed using receiver operating characteristic curves (ROC). RESULTS: Alpha values showed acceptable levels of internal consistency, ranging between 0.702 and 0.917 in all scales of BR23. The statistical analysis revealed significant test-retest correlations in most scales of BR23. The correlations between BR23 and similar domains of C30 and SF36 questionnaires were also significant. The BR23 questionnaire demonstrated satisfactory levels of sensitivity and specificity when compared with the SF-36 scale. CONCLUSIONS: The BR23 questionnaire adapted for use in Chile is linguistically appropriate and psychometrically valid.
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Neoplasias de la Mama/psicología , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/diagnóstico , Chile , Femenino , Humanos , Persona de Mediana Edad , Calidad de Vida , Curva ROC , Sensibilidad y Especificidad , Encuestas y CuestionariosRESUMEN
Background: Quality of Life assessment in oncologic patients evaluates the impact ana sequels of the disease ana the adverse effects of available treatments. Aim: To validate in Chile the breast cáncer specific-questionnaire (BR23) developed by the European Organization for Research and Treatment of Cancer (EORTC). Patients and Methods: After performing a linguistic validation of the BR23 according to EORTC instructions, its psychometric properties were tested in 103 patients with breast cancer whose ages ranged from 34 to 83 years. Infernal consistency ofthe scales was assessed using the Cronbach's alpha coefficient. The test-retest correlations of each scale (n = 83) were evaluated. The correlation ofBR23 scales with SF36 version 2 and C30 version 3.0 scales was also assessed. The sensitivity and specificity of the instrument were analyzed using receiver operating characteristic curves (ROC). Results: Alpha values showed acceptable levels of internal consistency, ranging between 0.702 and 0.917 in all scales of BR23. The statistical analysis revealed significant test-retest correlations in most scales ofBR23. The correlations between BR23 and similar domains of C30 and SF36 questionnaires were also significant. The BR23 questionnaire demonstrated satisfactory levels of sensitivity and specificity when compared with the SF-36 scale. Conclusions: The BR23 questionnaire adapted for use in Chile is linguistically appropriate and psychometrically valid.
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Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Persona de Mediana Edad , Neoplasias de la Mama/psicología , Neoplasias de la Mama/diagnóstico , Chile , Calidad de Vida , Encuestas y Cuestionarios , Curva ROC , Sensibilidad y EspecificidadRESUMEN
Objective. To validate the utility of 4D Blood Flow and Navier-Stokes equations to create relative pressure (RP) maps in the aorta and pulmonary artery (PA) in healthy volunteers and patients with repaired tetralogy of Fallot (TOF). Methods. A 4D flow sequence of whole heart and its major vessels was acquired in 10 healthy volunteers and 6 patients with repaired TOF. The root of the ascending aorta was used as the reference point to calculate RP along five different points of this area. In addition, relative pressure of both right and left PA was measured as correlated to absolute pressure. Results. Patients with repaired TOF showed greater pulmonary artery (PA) relative pressure differences between maximum and minimum values when compared to volunteers (p <0.05). Additionally, aortic relative pressures had an excellent correlation with published data, whether using 4D flow or by catheterization. Conclusions. 4D Flow MRI may represent a new non-invasive and non operator-dependent diagnostic tool in CV disease management.
Objetivo. Utilizar 4D Flow y las ecuaciones de Navier-Stokes para obtener mapas de presiones relativas (PR) en la Aorta y Arteria Pulmonar (AP) de voluntarios y pacientes con Tetralogía de Fallot reparada (TOFr). Métodos. En 10 voluntarios y 6 pacientes con TOFr se adquirió la secuencia 4D flow del corazón y sus principales vasos. La raíz de la Aorta Ascendente se utilizó como referencia para calcular las PR a esta zona en cinco puntos distintos. Además, se midió la PR de la AP derecha e izquierda respecto a la AP. Resultados. Los pacientes con TOFr tuvieron diferencias de PR entre los valores máximos y mínimos más grandes que los voluntarios en la AP (p<0,05). Adicionalmente, las PR de la aorta tuvieron una excelente correlación con datos publicados utilizando 4D flow y mediante cateterización. Conclusiones. 4D Flow podría constituir una nueva herramienta diagnóstica, no invasiva, ni operador dependiente, en el manejo de patologías CV.
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Persona de Mediana Edad , Aorta Torácica/fisiopatología , Arteria Pulmonar/fisiopatología , Imagen por Resonancia Magnética , Tetralogía de Fallot/fisiopatología , Velocidad del Flujo Sanguíneo , PresiónRESUMEN
Background. Increase in visceral fat is associated to the development of fatty liver and liver fibrosis. Hepatic elastography is a novel noninvasive method for assessing liver fibrosis. Objective. To evaluate the relationship between visceral adipose tissue volume (VAT), subcutaneous adipose tissue volume (SAT) as measured by Magnetic Resonance Imaging (MRI) and transient elastography (TrE) values using ARFI (Acoustic Radiation Force Impulse) in type 2 Diabetic Mellitus patients (DM2). Methods. We included 20 DM2 patients (mean age: 62 years, range: 55-75, mean weight: 77.8 kg, range: 61.5-97). Patients underwent an MRI study in a Philips Intera 1.5T scanner. MR imaging protocol included a spectral excitation sequence centered on the fat peak. The sequence included 32 cross sections, 7mm thick, from the diaphragmatic cupula to the inferior border of the kidney. VAT was measured by using the semiautomatic Image J software. Each patient underwent a hepatic elastograpy (HE); 10 ARFI measurements were performed in the right hepatic lobe. Finally, a statistical analysis was performed by applying Pearson correlation between abdominal fat volumes and ARFI scores Results. Mean VAT was 2472 +/- 861 cc, (1173-4020 cc), whilst the mean ARFI was 1.62 ± 0.8 m/s, (0.8-3.4 m/s). Correlations obtained were r=0.08 between VAT and ARFI (p=0.72); 0.13 between SAT and ARFI (p=0.57), and -0.06 between (VAT+SAT) and ARFI (p=0.77). By subdividing the sample universe, we observed that the group with ARFI scores greater than 1.6 m/s (7 patients) had a correlation of 0.63 between VAT and ARFI (p=0.12); of 0.66 between SAT and ARFI (p=0.10), and of 0.94 between VAT+SAT and ARFI (p=0.001). In the subgroup with ARFI values inferior to 1.6 m/s (13 patients), the correlation was of 0.11 between VAT and ARFI (p=0.71); of 0.26 between SAT and ARFI (p=0.38), and of 0.32 between ( VAT+SAT) and ARFI (p=0.28). When adjusted for gender, ARFI scores greater than.
Introducción. La acumulación de grasa visceral se asocia al desarrollo de enfermedad hepática. La elastografía hepática es un método novedoso no invasivo para evaluar fibrosis hepática. Objetivo. Evaluar la relación entre el volumen de tejido adiposo visceral (VAT), volumen de tejido adiposo subcutáneo (SAT) medido por resonancia magnética (RM), con índices de elastografía hepática (EH) utilizando ARFI (fuerza de impulso de radiación acústica) en pacientes con Diabetes Mellitus tipo 2 (DM2). Métodos. Fueron incluidos 20 pacientes (edad promedio: 62 años, rango: 55-75 años, peso promedio: 77,8 kg, rango: 61,5-97 kg) con DM2. Los pacientes se sometieron a un examen de RM en un resonador Philips Intera 1.5T. Al protocolo de RM se agregó una secuencia de excitación espectral centrada en el peak de grasa. La secuencia incluyó 32 cortes transversales, grosor 7mm, desde la cúpula diafragmática hasta el borde inferior renal. En las imágenes se midió VAT utilizando el software Image J (freeware). En cada paciente se realizó una EH, utilizando ARFI con 10 medidas en lóbulo hepático derecho. Finalmente, se realizó un análisis estadístico a través de la correlación de Pearson entre los volúmenes de grasa abdominal y ARFI. Resultados. El promedio de VAT fue 2472 +/- 861 cc, (1173-4020 cc), el promedio de ARFI fue 1,62 ± 0,8 m/s, (0,8-3,4 m/s). Se obtuvieron correlaciones de r=-0,08 entre VAT y ARFI (p=0,72), de 0,13 entre SAT y ARFI (p=0,57), y de -0,06 entre (VAT+SAT) con ARFI (p=0,77). Subdividiendo el universo muestral, se encontró que el grupo con ARFI mayor que 1,6 m/s (7 pacientes) obtuvo una correlación de 0,63 entre VAT y ARFI (p=0,12), de 0,66 entre SAT y ARFI (p=0,10), y de 0,94 entre (VAT+SAT) con ARFI (p=0,001). En el subgrupo con ARFI inferior a 1,6 m/s (13 pacientes) la correlación fue 0,11 entre VAT y ARFI (p=0,71), de 0,26 entre SAT y ARFI (p=0,38), y de 0,32 entre (VAT+SAT) y ARFI (p=0,28).
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Humanos , Masculino , Femenino , Persona de Mediana Edad , /patología , Diagnóstico por Imagen de Elasticidad/métodos , Grasa Intraabdominal/anatomía & histología , Hígado/patología , Cirrosis Hepática/diagnóstico , Hígado Graso/diagnóstico , Imagen por Resonancia Magnética , Medición de Riesgo , Tejido Adiposo/anatomía & histologíaRESUMEN
Purpose. To demonstrate the utility of 4D flow MR imaging for analyzing blood flow patterns and flow distribution in patients with congenital heart diseases. Methods: Six patients with congenital heart diseases were scanned using a standard cardiac MRI protocol, according to their condition. Additionally, 2D flow sequences of the great vessels, and a 4D flow sequence covering the entire heart were acquired. Flow patterns were visualized by using vector fields, streamlines and particle traces. Results: 4D flow technique depicted vortices and helical flow in the pulmonary artery of most patients, as well as in the aorta and superior vena cava of one patient with corrected aortic coarctation and a levoatrial cardinal vein. Conclusion: 4D flow MR imaging enables the identification of flow patterns difficult to detect with other diagnostic modalities. Comprehensive evaluation of flow patterns might help to understand the hemodynamic consequences of congenital heart diseases and their surgical procedures.
Objetivo. Demostrar la utilidad de 4D flow para el análisis de patrones y distribución de flujos en pacientes con cardiopatías congénitas. Métodos: Seis pacientes con cardiopatías congénitas fueron escaneados con un protocolo de resonancia magnética cardíaca estándar. Además se incluyeron secuencias de flujo 2D en los principales vasos del tórax y una secuencia 4D flow que cubría todo el corazón. Para la visualización de los patrones de flujo se emplearon vectores de velocidad, líneas de flujo y trazadores de partículas. Resultados: 4D flow reveló vórtices y hélices en la arteria pulmonar de la mayoría de los pacientes, y en la aorta y vena cava superior de un paciente con coartación aórtica reparada y vena cardinal levoatrial. Conclusiones: 4D flow permite identificar patrones de flujo en pacientes con cardiopatías congénitas, difíciles de observar con otros métodos diagnósticos. La evaluación de patrones de flujo podría contribuir a comprender las consecuencias hemodinámicas de diferentes cardiopatías congénitas.
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Humanos , Masculino , Adolescente , Adulto , Femenino , Niño , Persona de Mediana Edad , Cardiopatías Congénitas/diagnóstico , Cardiopatías Congénitas/fisiopatología , Imagen por Resonancia Magnética/métodos , Velocidad del Flujo Sanguíneo/fisiología , Aorta Torácica/fisiopatología , Arteria Pulmonar/fisiopatología , Aumento de la Imagen/métodos , Coartación Aórtica/fisiopatología , Flujo Sanguíneo Regional , Vena Cava Superior/fisiopatologíaRESUMEN
Introduction: The acquisition process in magnetic resonance images (MRI) is slow. One approach to reduce the acquisition times is the reconstruction of undersampled data. i.e. to acquire less samples that those needed for standard application, and to reconstruct the unknown samples using mathematical algorithms. We propose to used reconstruction techniques for undersampled data based on Compressed Sensing (CS) to decrease the acquisition times, obtaining identical MRI as those obtained with all samples. Methods: We performed reconstructions of undersampled data obtained from phantoms and MRI with 60 percent, 55 percent and 50 percent of the samples. Results: When the number of samples was more that the double of pixels with non cero intensity, the reconstructions where identical to the original ones. For the MRI experiment, this was achieved with 60 percent of the samples, therefore obtaining a 40 percent of reduction in the acquisition time. Discussion: Our reconstruction technique based on CS is an effective way for reducing the acquisition times in MRI.
Introducción: El proceso de adquisición de imágenes por resonancia magnética (IRM) es lento. Una forma para disminuir los tiempos de adquisición es a través de reconstrucciones de datos submuestreados, es decir tomar menos muestras que las necesarias en aplicaciones estándares, y reconstruir las muestras faltantes a través de algoritmos matemáticos. Proponemos utilizar técnicas de reconstrucción de datos submuestreados basadas en técnicas de Compressed Sensing (CS) para disminuir los tiempos de adquisición, obteniendo imágenes idénticas a las obtenidas con todas las muestras. Métodos: Realizamos reconstrucciones de datos submuestreados de fantomas y IRM con 60 por ciento, 55 por ciento y 50 por ciento de las muestras. Resultados: Cuando el número de muestras fue mayor al doble del número de pixeles con intensidad cero, las reconstrucciones obtenidas fueron idénticas a las originales. Para las IRM esto se logró con 60 por ciento de las muestras, logrando reducciones del 40 por ciento en los tiempos de adquisición. Discusión: Nuestra técnica de reconstrucción basada en CS es una forma efectiva para reducir los tiempos de adquisición de IRM.
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Humanos , Imagen por Resonancia Magnética/métodos , Procesamiento de Imagen Asistido por Computador/métodos , Aumento de la Imagen/métodos , Compresión de Datos/métodos , Factores de Tiempo , Fantasmas de Imagen , Imagen por Resonancia Magnética/instrumentación , Reacciones Falso Negativas , Reacciones Falso Positivas , Valor Predictivo de las PruebasRESUMEN
The role of neuropeptide Y (NPY) as a modulator of the vasomotor responses mediated by sympathetic cotransmitters was examined by electrically evoking its release from the perivascular nerve terminals of second- to third-order human blood vessel biopsies and by studying the peptide-induced potentiation of the vasomotor responses evoked by exogenous adenosine 5' triphosphate (ATP) and noradrenaline (NA). Electrical depolarization of nerve terminals in mammary vessels and radial artery biopsies elicited a rise in superfusate immunoreactive NPY (ir-NPY), which was chromatographically identical to a standard of human NPY (hNPY); a second peak was identified as oxidized hNPY. The amount released corresponds to 4-6% of the total NPY content in these vessels. Tissue extracts also revealed two peaks; hNPY accounted for 68-85% of the ir-NPY, while oxidized hNPY corresponded to 7-15%. The release process depended on extracellular calcium and on the frequency and duration of the electrical stimuli; guanethidine blocked the release, confirming the peptide's sympathetic origin. Assessment of the functional activity of the oxidized product demonstrated that while it did not change basal tension, the NA-evoked contractions were potentiated to the same extent as with native hNPY. Moreover, NPY potentiated both the vasomotor action of ATP or NA alone and the vasoconstriction elicited by the simultaneous application of both cotransmitters. RT-PCR detected the mRNA coding for the NPY Y(1) receptor. In summary, the release of hNPY or its oxidized species, elicited by nerve terminal depolarization, coupled to the potentiation of the sympathetic cotransmitter vasomotor responses, highlights the modulator role of NPY in both arteries and veins, strongly suggesting its involvement in human vascular sympathetic reflexes.
Asunto(s)
Fibras Adrenérgicas/metabolismo , Arterias Mamarias/inervación , Arterias Mamarias/fisiología , Neuropéptido Y/metabolismo , Arteria Radial/inervación , Arteria Radial/fisiología , Adenosina Trifosfato/farmacología , Anciano , Biopsia , Calcio/metabolismo , Sinergismo Farmacológico , Estimulación Eléctrica , Femenino , Guanetidina/farmacología , Humanos , Técnicas In Vitro , Masculino , Arterias Mamarias/patología , Persona de Mediana Edad , Neuropéptido Y/farmacología , Norepinefrina/farmacología , Arteria Radial/patología , Receptores de Neuropéptido Y/metabolismo , Simpaticolíticos/farmacología , Simpatomiméticos/farmacología , Transmisión Sináptica/efectos de los fármacos , Transmisión Sináptica/fisiología , Vasoconstricción/efectos de los fármacos , Vasoconstricción/fisiologíaRESUMEN
Transmural electrical stimulation of the sympathetic nerve endings of human saphenous vein biopsies released two forms of NPY identified chromatographically as native and oxidized peptide. The release process is dependent on extracellular calcium, the frequency, and the duration of the stimuli. While guanethidine reduced the overflow of ir-NPY, phenoxybenzamine did not augment NPY release, but increased that of noradrenaline. Oxidized NPY, like native NPY, potentiated the noradrenaline and adenosine 5'-triphospahate-induced vasoconstriction, an effect blocked by BIBP 3226 and consonant with the RT-PCR detection of the mRNA encoding the NPY Y1 receptor. These results highlight the functional role of NPY in human vascular sympathetic reflexes.
Asunto(s)
Neuropéptido Y/fisiología , Vena Safena/inervación , Adenosina Trifosfato/farmacología , Anciano , Calcio/metabolismo , Cromatografía Líquida de Alta Presión , Relación Dosis-Respuesta a Droga , Estimulación Eléctrica , Guanetidina/farmacología , Humanos , Masculino , Persona de Mediana Edad , Neuropéptido Y/metabolismo , Fenoxibenzamina/farmacología , Vena Safena/química , Vena Safena/efectos de los fármacos , Transmisión Sináptica , VasoconstricciónRESUMEN
BACKGROUND: The natural history of aneurysms ends in rupture and death. In 1990 the first endovascular exclusion of an aneurysm, using an endoluminal graft implanted through the femoral arteries was performed. More recently, the same procedure has been used for aneurysms of the thoracic aorta. AIM: To report our experience with endovascular treatment of thoracic aorta aneurysms. MATERIAL AND METHODS: Analysis of 14 patients (nine male), aged 30 to 79 years, treated between May 2001 and August 2002. RESULTS: The mean diameter of the aneurysms was 6.9 cm. The etiology was atherosclerotic in nine patients. The Excluder device (Gore) was preferentially used. There was no operative mortality or paraplegia. One patient had a transient leg monoparesis that reverted completely. No patient had type I endoleaks. Two patients had type II endoleaks on discharge, that sealed spontaneously. In a follow up, ranging from 2 to 17 months, one patient died of a bronchopneumonia and no aneurysm rupture has been detected. CONCLUSIONS: The short term results of endoluminal treatment of thoracic aorta aneurysms are excellent. This treatment is less invasive and has less complications than conventional surgery.
Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Aneurisma de la Aorta Torácica/cirugía , Angioplastia/métodos , Implantación de Prótesis Vascular , Aneurisma de la Aorta Torácica/diagnóstico , Aneurisma de la Aorta Torácica/etiología , Enfermedad de la Arteria Coronaria/complicaciones , Factores de Riesgo , Resultado del Tratamiento , Tomografía Computarizada por Rayos XRESUMEN
BACKGROUND: Few data exist regarding angiographic predictors of radial artery patency for coronary bypass grafting, and the benefit of calcium antagonists is not clear. METHODS: One hundred fifteen patients were studied who had myocardial revascularization with the radial artery plus internal mammary and vein grafts with 3.5 +/- 1.1 grafts per patient. Sixty-three patients received diltiazem and 52 patients did not. Base line and follow-up angiographies were analyzed 1 year postoperatively in 50 of these patients with a quantitative computerized method. RESULTS: One hundred fourteen patients survived and were followed for 30.1 +/- 12.6 months. Patency for mammary grafts was 100%, for radial grafts it was 80%, and for saphenous vein grafts it was 68%. Patent radial artery grafts had significantly greater degree of stenosis in the native vessels than occluded grafts (73% +/- 14% vs 40% +/- 24%), (p = 0.0007; confidence interval = 95%). Radial artery patency increased to 92% when arteries with 70% or more stenosis were considered. No differences were observed for clinical and angiographic end points in the patients that received diltiazem compared with the rest who had not. CONCLUSIONS: The degree of stenosis in the native coronary artery significantly influences the patency rate of radial artery grafts, independent of diltiazem.
Asunto(s)
Puente de Arteria Coronaria , Arteria Radial/trasplante , Grado de Desobstrucción Vascular , Adulto , Anciano , Femenino , Estudios de Seguimiento , Humanos , Masculino , Arterias Mamarias/trasplante , Persona de Mediana Edad , Complicaciones Posoperatorias/epidemiología , Vena Safena/trasplanteRESUMEN
Mediastinitis with graft infection is a serious complication of ascending aorta replacement. We report two cases of graft infection, treated with surgical cleaning, graft preservation and transposition of muscle flaps. A 62 years old male was admitted 34 days after an ascending aortic grafting due to a sternal dehiscence and mediastinitis. Antimicrobial treatment was started and a surgical cleaning performed, leaving an open sternotomy. Three days later, the thoracic cavity was closed with a rectus abdominis muscle flap. After 23 months of follow up, the patient is well and without evidence of infection. A 74 years old male was subjected to an aortic valve and ascending aorta replacement and a myocardial revascularization. In the postoperative period, the patient developed septic signs, and a purulent drainage. A CAT scan showed a liquid collection surrounding the aortic graft. On tW Sixteenth postoperative day, a surgical cleaning was performed and the thorax was closed with the pectoralis major muscle. After 10 months of follow up, the patient is in Good condition and without evidence of infection.
Asunto(s)
Aorta/trasplante , Prótesis Vascular/efectos adversos , Mediastinitis/cirugía , Infecciones Relacionadas con Prótesis/cirugía , Colgajos Quirúrgicos , Anciano , Humanos , Masculino , Persona de Mediana Edad , Infecciones por Pseudomonas/microbiología , Infecciones Estafilocócicas/microbiología , Tomografía Computarizada por Rayos XRESUMEN
BACKGROUND: Coronary artery bypass grafting (CABG) reoperation is being performed with increasing frequency. AIM: To assess the early and long term results of coronary reoperations in our institution and to identify prognostic factors. PATIENTS AND METHODS: 214 patients subjected to coronary reoperations between 1983 and 1999 were retrospectively studied. RESULTS: Mean age was 64.2 years (range 42-79 years), 202 (94.4%) were male and 12 (5.6%) female. The mean interval between the operations was 125.7 months (range 6-252 months). 10 (4.6%) were emergency surgeries. Overall operative mortality was 5.6% (11 deaths) and in 5 patients (3.4%) a perioperative myocardial infarction was noted. Univariate analysis identified moderate or severe left ventricular failure (p = 0.048) as predictor of increased operative mortality, meanwhile age over 75 years (p = 0.02) and moderate or severe left ventricular failure (p = 0.01) were identified as predictors of increased in hospital mortality in the multivariate analysis. Follow up of in hospital survivors (mean interval 65 months, range 4 to 190 months) documented a 5 years survival rate of 82.9%, a 10 years survival rate of 73.1% and a 15 years survival rate of 53.4%. Moderate or severe left ventricular failure (p < 0.0001) and emergency surgeries (p = 0.007) were identified as factors influencing the late survival in the stepwise logistical regression analysis. Multivariate analysis identified left ventricular failure (p = 0.01) and peripheral vascular disease (p = 0.01) as predictors of decreased late survival. CONCLUSIONS: Coronary reoperation has a low mortality in patients with a normal ventricular function and also has an excellent overall and disease free survival in the first 10 years of follow up. Left ventricular function is an independent risk factor increasing in hospital and late mortality.