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1.
Tijdschr Psychiatr ; 63(6): 451-454, 2021.
Artículo en Holandés | MEDLINE | ID: mdl-34231864

RESUMEN

BACKGROUND: The mission in Dutch youth care is to work together to help the child and its family in the best possible way. Child and adolescent psychiatric consultation seems a good way to contribute to this mission, but this is not self-explanatory. Many colleagues feel uncertain how to maintain their medical responsibility. AIM: To provide insight in the consultation process, which legislation to apply as well as its practical consequences in various settings. METHOD: The effect of legislation is worked out in various consultative settings. The consequences for the process of consultation are worked out as well as the consequences for the persons involved. RESULTS: Consultation is a good way to collaborate with adult psychiatry as well as youth care. It is important to realise the different roles as well as the different legislative consequences, because of its influence on the consultation process. CONCLUSION: While there is a need for psychiatric consultation in the field of youth care, it still is not an obvious method. In addition to political and financial limitations there is uncertainty in the field how to develop consultation the best way. The Dutch Society of Psychiatry published a supportive Guide on consultation, aiming to help in a practical way.


Asunto(s)
Psiquiatría , Adolescente , Adulto , Niño , Familia , Humanos , Derivación y Consulta
4.
Acta Anaesthesiol Scand ; 62(3): 347-356, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29210062

RESUMEN

BACKGROUND: Mechanical ventilation with oxygen is life-saving, however, may result in hyperoxia. The aim was to analyse the incidence and duration of hyperoxia burden and related in-hospital mortality in critically ill patients. METHODS: Patients of all ages admitted to intensive care units (ICUs) and with mechanical ventilation for at least seven consecutive days were included in this single centre retrospective medical record audit. The main outcome measure was time-weighted arterial partial pressure of oxygen (PaO2 ) over 7 days. Logistic regression for association with in-hospital mortality and propensity score matching was performed. RESULTS: In total, 20,889 arterial blood gases of 419 patients were analysed. Time-weighted mean PaO2 was 14.0 ± 2.4 kPa. Time-weighted mean FiO2 was 49.2 ± 12.1%. Seventy-six (18.1%) patients showed continuous hyperoxia exposure, defined as time-weighted mean PaO2 > 16 kPa. Duration of hyperoxia, hypoxia (PaO2 < 8 kPa) and normoxia (PaO2 8-16 kPa) were 37.9 ± 31.0 h (23.7%), 4.9 ± 9.5 h (3.1%), and 116.8 ± 29.6 h (73.2%). Hyperoxia occurred especially at low to moderate FiO2 in patients of first and second age quartiles (1-57 years) with smaller SAPS2 score. In-hospital mortality of patients with hyperoxia (32.9%) or normoxia did not differ (35.9%; P = 0.691). Conditional logistic regression showed no association between hyperoxia and in-hospital mortality (OR 1.46; 95%CI 0.72-2.96; P = 0.29). CONCLUSION: Substantial hyperoxia burden was observed in ICU patients. Young patients with less comorbidities showed hyperoxic episodes more often, especially with lower FiO2 . Hyperoxia during 7 days of mechanical ventilation did not correlate to increased in-hospital mortality.


Asunto(s)
Enfermedad Crítica/mortalidad , Mortalidad Hospitalaria , Hiperoxia/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Análisis de Datos , Femenino , Humanos , Incidencia , Lactante , Modelos Logísticos , Masculino , Persona de Mediana Edad , Oxígeno/sangre , Estudios Retrospectivos , Adulto Joven
5.
Anaesthesist ; 66(5): 318-324, 2017 May.
Artículo en Alemán | MEDLINE | ID: mdl-28353067

RESUMEN

BACKGROUND: In business conflicts have long been known to have a negative effect on costs and team performance. In medicine this aspect has been widely neglected, especially when optimizing processes for operating room (OR) management. In the multidisciplinary setting of OR management, shortcomings in rules for decision making and lack of communication result in members perceiving themselves as competitors in the patient's environment rather than acting as art of a multiprofessional team. This inevitably leads to the emergence and escalation of conflicts. OBJECTIVE: We developed a conflict matrix to provide an inexpensive and objective way for evaluating the level of escalation of conflicts in a multiprofessional working environment, such as an OR. MATERIAL AND METHODS: The senior members of all involved disciplines were asked to estimate the level of conflict escalation between the individual professional groups on a scale of 0-9. By aggregating the response data, an overview of the conflict matrix within this OR section was created. RESULTS: No feedback was received from 1 of the 11 contacted occupational groups. By color coding the median, minimum and maximum values of the retrieved data, an intuitive overview of the escalation levels of conflict could be provided. The value range of all feedbacks was between 0 and 6. Estimation of the escalation levels differed widely within one category, showing a range of up to 6 (out of 6) levels. CONCLUSION: The presented assessment using a conflict matrix is a simple and cost-effective method to assess the conflict landscape, especially in multidisciplinary environments, such as OR management. The chance of conflict prevention or the early recognition of existing conflicts represents an enormous potential for cost and risk saving and might have positive long-term effects by building a culture of conflict prevention at the workplace and a positive influence on interdisciplinary cooperation in this working environment.


Asunto(s)
Quirófanos/organización & administración , Gestión de Riesgos/organización & administración , Algoritmos , Toma de Decisiones Clínicas , Comunicación , Conflicto Psicológico , Humanos , Relaciones Interprofesionales , Negociación , Grupo de Atención al Paciente/organización & administración
7.
Oncogene ; 36(15): 2105-2115, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27775078

RESUMEN

Deletion or mutation of the gene encoding the deubiquitinating enzyme CYLD is a common genomic aberration in multiple myeloma (MM). However, the functional consequence of CYLD loss and the mechanism underlying its putative role as a tumor suppressor gene in the pathogenesis of MM has not been established. Here, we show that CYLD expression is highly variable in myeloma cell lines and primary MMs and that low CYLD expression is associated with disease progression from monoclonal gammopathy of undetermined significance to MM, and with poor overall and progression free-survival of MM patients. Functional assays revealed that CYLD represses MM cell proliferation and survival. Furthermore, CYLD acts as a negative regulator of NF-κB and Wnt/ß-catenin signaling and loss of CYLD sensitizes MM cells to NF-κB-stimuli and Wnt ligands. Interestingly, in primary MMs, low CYLD expression strongly correlated with a proliferative and Wnt signaling-gene expression signature, but not with an NFκB target gene signature. Altogether, our findings identify CYLD as a negative regulator of NF-κB and Wnt/ß-catenin signaling in MM and indicate that loss of CYLD enhances MM aggressiveness through Wnt pathway activation. Thus, targeting the Wnt pathway could be a promising therapeutic strategy in MM with loss of CYLD activity.


Asunto(s)
Mieloma Múltiple/metabolismo , Mieloma Múltiple/patología , Proteínas Supresoras de Tumor/deficiencia , Vía de Señalización Wnt , Estudios de Casos y Controles , Enzima Desubiquitinante CYLD , Humanos , Mieloma Múltiple/genética , FN-kappa B/metabolismo , Transfección , Proteínas Supresoras de Tumor/genética , Proteínas Supresoras de Tumor/metabolismo
8.
Anaesthesist ; 64(12): 901-902, 2015 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-26630986
9.
Anaesthesist ; 64(3): 227-34, 2015 Mar.
Artículo en Alemán | MEDLINE | ID: mdl-25630518

RESUMEN

BACKGROUND: Statistically, the chance of a patient to win a court case because of a legally insufficient informed consent is approximately 70%. In Austria the judgment whether the anesthesia-related risk of a patient was correctly addressed depends generally on the opinion of a certified expert court witness (CW). OBJECTIVES: The opinion whether well-known anesthetic risks in a commissioned court report drawn by Austrian CWs would be considered to be "typically anesthesia-related" and "needed to be addressed" when obtaining an informed consent was evaluated. MATERIALS AND METHODS: A questionnaire was sent to all Austrian CWs with 79 known anesthesia-related risks. The percentage of CWs who considered the enumerated risks as "typically anesthesia related" and "needed to be addressed" when obtaining informed consent was evaluated. RESULTS: In 32 out of 79 risks between 40% and 60% of the CWs were of the opinion that informed consent was necessary. Therefore, in a legal dispute on whether an informed consent was legally sufficient or not, the judgment of the CWs is unpredictable. In addition, due to the large number of possible complications needed to be addressed, it is not feasible to obtain a legally compliant risk disclosure. CONCLUSION: In future new methods of knowledge transfer to the patients should be developed. In addition, a standardization of the evaluation criteria for CWs in terms of improvement of legal certainty would be desirable.


Asunto(s)
Anestesia/efectos adversos , Consentimiento Informado/legislación & jurisprudencia , Consentimiento Informado/normas , Austria , Comunicación , Humanos , Pacientes , Riesgo , Encuestas y Cuestionarios
10.
Oncogene ; 33(5): 665-70, 2014 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-23318432

RESUMEN

A gene signature specific for intestinal stem cells (ISCs) has recently been shown to predict relapse in colorectal cancer (CRC) but the tumorigenic role of individual signature genes remains poorly defined. A prominent ISC-signature gene is the cancer stem cell marker CD44, which encodes various splice variants comprising a diverse repertoire of adhesion and signaling molecules. Using Lgr5 as ISC marker, we have fluorescence-activated cell sorting-purified ISCs to define their CD44 repertoire. ISCs display a specific set of CD44 variant isoforms (CD44v), but remarkably lack the CD44 standard (CD44s) isoform. These CD44v also stand-out in transformed human ISCs isolated from microadenomas of familial adenomatous polyposis patients. By employing knock-in mice expressing either CD44v4-10 or CD44s, we demonstrate that the CD44v isoform, but not CD44s, promotes adenoma initiation in Apc(Min/+)mice. Our data identify CD44v as component of the ISCs program critical for tumor initiation, and as potential treatment target in CRC.


Asunto(s)
Poliposis Adenomatosa del Colon/genética , Transformación Celular Neoplásica/genética , Receptores de Hialuranos/genética , Receptores de Hialuranos/metabolismo , Neoplasias Intestinales/metabolismo , Animales , Citometría de Flujo , Perfilación de la Expresión Génica , Técnicas de Sustitución del Gen , Ratones , Ratones Transgénicos , Células Madre Neoplásicas/citología , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Receptores Acoplados a Proteínas G/genética , Células Tumorales Cultivadas , Vía de Señalización Wnt/genética
11.
Leukemia ; 27(8): 1729-37, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23478664

RESUMEN

In multiple myeloma (MM), angiogenesis is strongly correlated to disease progression and unfavorable outcome, and may be promoted by bone marrow hypoxia. Employing gene-expression profiling, we here identified the pro-angiogenic factor adrenomedullin (AM) as the most highly upregulated gene in MM cells exposed to hypoxia. Malignant plasma cells from the majority of MM patients, belonging to distinct genetic subgroups, aberrantly express AM. Already under normoxic conditions, a subset of MM highly expressed and secreted AM, which could not be further enhanced by hypoxia or cobalt chloride-induced stabilization of hypoxia-inducible factor (HIF)1α. In line with this, expression of AM did not correlate with expression of a panel of established hypoxia-/HIF1α-target genes in MM patients. We demonstrate that MM-driven promotion of endothelial cell proliferation and tube formation is augmented by inducible expression of AM and strongly repressed by inhibition of endogenous and hypoxia-induced AM activity. Together, our results demonstrate that MM cells, both in a hypoxia-dependent and -independent fashion, aberrantly express and secrete AM, which can mediate MM-induced angiogenesis. Thus, AM secretion can be a major driving force for the angiogenic switch observed during MM evolution, which renders AM a putative target for MM therapy.


Asunto(s)
Adrenomedulina/genética , Regulación Neoplásica de la Expresión Génica , Hipoxia/genética , Mieloma Múltiple/genética , Mieloma Múltiple/patología , Neovascularización Patológica/genética , Línea Celular Tumoral , Progresión de la Enfermedad , Perfilación de la Expresión Génica , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/genética , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Mieloma Múltiple/metabolismo , FN-kappa B/genética , FN-kappa B/metabolismo , Transcripción Genética
12.
Burns ; 38(3): 444-9, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22071361

RESUMEN

PURPOSE: A successful online presence is an important key factor in the competition among hospitals today. However, little is known about the internet presence and the quality of websites of burn units on the World Wide Web. The aim was to assess the online presence of hospitals provided by specialized burn units in German speaking countries with a focus on the rate and the performance of actively run websites. METHODS: A multicenter, observational, cross-sectional study was performed over a period of 1.5 month (October-December 2010). Forty-four burn units were assessed by using a previously generated criteria list. The list included 36 criteria with following topics: "research and teaching"; "patient care"; "clinical emphases", "general information"; "information brokerage". RESULTS: Overall, the websites examined offered a good overview about their different online services with many multimedia-based elements included. All websites consisted of hyperlinks, general multimedia-based elements and information on means of communication with the hospital, respectively. In contrast, the quality of specific information for burn patients was relatively poor. With regard to the need of elderly people, the usability and the layout, the different websites offer a lot of options for future improvements. CONCLUSION: Burn centers in Germany, Austria and Switzerland already consider the World Wide Web as an important tool for self-promotion and communication. The potential of burn center websites to function as a knowledge base for first aid as well as preventive measurements should be considered and realized in future web site designs.


Asunto(s)
Unidades de Quemados , Sistemas de Información en Hospital/organización & administración , Internet/estadística & datos numéricos , Austria , Unidades de Quemados/organización & administración , Estudios Transversales , Alemania , Sistemas de Información en Hospital/normas , Humanos , Suiza
13.
AJNR Am J Neuroradiol ; 33(4): 747-54, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22194365

RESUMEN

BACKGROUND AND PURPOSE: Semiautomated methods for ICA stenosis measurements have the potential to reduce interobserver variability and to speed up its analysis. In this study, we estimate the precision and accuracy of a semiautomated measurement for carotid artery stenosis degree and identify and explain differences compared with the manual method. MATERIALS AND METHODS: In this retrospective study involving 90 patients, 2 observers determined the stenosis degree twice, with both the semiautomated and the manual method. Intra- and interobserver correlations were calculated for both methods. The accuracy was estimated by comparing average semiautomated with manual measurements. The semiautomated stenosis calculations were performed using either the minimal or maximal intersection at the reference site. Individual cases with large differences in measurement were retrospectively inspected by 3 observers. RESULTS: Intra- (R = 0.93, 0.96) and interobserver (R = 0.98) correlations for the semiautomated method were excellent and exceeded the manual performance correlations (R = 0.87, 0.86). The semiautomated measurements correlated well with the manual measurements (R = 0.87), with high specificity of 96% and lower sensitivity of 63%. Large differences were caused by misinterpretations of the semiautomated method associated with calcified plaques, resulting in overestimations of the minimal diameter, underestimation of stenosis degree, and incorrect centerlines. The effect of using the minimal diameter at the reference position resulted in a small, but significant, underestimation of the stenosis degree by the semiautomated method. CONCLUSIONS: The semiautomated method showed an excellent reproducibility and good correlation with manual measurements with a high specificity and lower sensitivity for detecting a significant stenosis. Erroneous semiautomatic stenosis measurements were associated with the presence of calcium.


Asunto(s)
Algoritmos , Estenosis Carotídea/diagnóstico por imagen , Angiografía Cerebral/métodos , Reconocimiento de Normas Patrones Automatizadas/métodos , Intensificación de Imagen Radiográfica/métodos , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
14.
Phys Med Biol ; 56(18): N183-93, 2011 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-21865622

RESUMEN

Attenuation of photon flux on trajectories between the source and pinhole apertures affects the quantitative accuracy of reconstructed single-photon emission computed tomography (SPECT) images. We propose a Chang-based non-uniform attenuation correction (NUA-CT) for small-animal SPECT/CT with focusing pinhole collimation, and compare the quantitative accuracy with uniform Chang correction based on (i) body outlines extracted from x-ray CT (UA-CT) and (ii) on hand drawn body contours on the images obtained with three integrated optical cameras (UA-BC). Measurements in phantoms and rats containing known activities of isotopes were conducted for evaluation. In (125)I, (201)Tl, (99m)Tc and (111)In phantom experiments, average relative errors comparing to the gold standards measured in a dose calibrator were reduced to 5.5%, 6.8%, 4.9% and 2.8%, respectively, with NUA-CT. In animal studies, these errors were 2.1%, 3.3%, 2.0% and 2.0%, respectively. Differences in accuracy on average between results of NUA-CT, UA-CT and UA-BC were less than 2.3% in phantom studies and 3.1% in animal studies except for (125)I (3.6% and 5.1%, respectively). All methods tested provide reasonable attenuation correction and result in high quantitative accuracy. NUA-CT shows superior accuracy except for (125)I, where other factors may have more impact on the quantitative accuracy than the selected attenuation correction.


Asunto(s)
Modelos Animales , Fantasmas de Imagen , Tomografía Computarizada de Emisión de Fotón Único/métodos , Animales , Radioisótopos de Yodo , Fotones , Ratas , Reproducibilidad de los Resultados , Dispersión de Radiación , Sensibilidad y Especificidad , Tecnecio , Radioisótopos de Talio , Tomografía Computarizada de Emisión de Fotón Único/instrumentación , Tomografía Computarizada por Rayos X/métodos
15.
AJNR Am J Neuroradiol ; 32(7): 1182-7, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21659483

RESUMEN

BACKGROUND AND PURPOSE: Recent research showed a strong correlation of calcium volume scores with degree of stenosis, suggesting that calcium volume could be used in the diagnosis of carotid artery stenosis. We investigated the accuracy of the use of calcium volume scores to diagnose carotid artery stenosis in our target population of recently symptomatic patients. MATERIALS AND METHODS: Ninety symptomatic patients suspected of having carotid artery stenosis underwent CTA, resulting in images of 159 evaluable arteries. The correlation between calcium volume and degree of stenosis was calculated by using the Pearson correlation coefficient. With thresholds of 0.03 and 0.09 mL, we assessed the diagnostic performance of a calcium volume-based evaluation of stenosis for a previously reported stenosis cutoff of 40% and for the clinically important cutoffs of 50% and 70%. RESULTS: In our patients series, the calcium volume score was not related to the stenosis degree on the symptomatic side (R = 0.04, P = .7) and was weakly related on the asymptomatic side (R = 0.29, P = .005). The diagnostic accuracy of the calcium volume score to estimate 40% stenosis was relatively low: a sensitivity of 47% or 64% and a specificity of 52% or 82%, for the 0.09 and 0.03 mL thresholds, respectively. The diagnostic accuracy decreased with increasing degree of stenosis. CONCLUSIONS: We could not confirm the previously reported strong correlation of calcium volume with stenosis degree in our population of patients with recent neurologic symptoms. We conclude that in this particular domain, calcium volume cannot be used to estimate the degree of stenosis.


Asunto(s)
Estenosis Carotídea/diagnóstico por imagen , Índice de Severidad de la Enfermedad , Tomografía Computarizada por Rayos X/métodos , Tomografía Computarizada por Rayos X/normas , Calcificación Vascular/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Angiografía de Substracción Digital/métodos , Angiografía de Substracción Digital/normas , Estenosis Carotídea/patología , Estenosis Carotídea/cirugía , Endarterectomía Carotidea , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Cuidados Preoperatorios/métodos , Cuidados Preoperatorios/normas , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Calcificación Vascular/patología , Calcificación Vascular/cirugía
16.
AJNR Am J Neuroradiol ; 32(3): 581-6, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21183614

RESUMEN

BACKGROUND AND PURPOSE: Patient-specific simulations of the hemodynamics in intracranial aneurysms can be constructed by using image-based vascular models and CFD techniques. This work evaluates the impact of the choice of imaging technique on these simulations. MATERIALS AND METHODS: Ten aneurysms, imaged with 3DRA and CTA, were analyzed to assess the reproducibility of geometric and hemodynamic variables across the 2 modalities. RESULTS: Compared with 3DRA models, we found that CTA models often had larger aneurysm necks (P = .05) and that most of the smallest vessels (between 0.7 and 1.0 mm in diameter) could not be reconstructed successfully with CTA. With respect to the values measured in the 3DRA models, the flow rate differed by 14.1 ± 2.8% (mean ± SE) just proximal to the aneurysm and 33.9 ± 7.6% at the aneurysm neck. The mean WSS on the aneurysm differed by 44.2 ± 6.0%. Even when normalized to the parent vessel WSS, a difference of 31.4 ± 9.9% remained, with the normalized WSS in most cases being larger in the CTA model (P = .04). Despite these substantial differences, excellent agreement (κ ≥ 0.9) was found for qualitative variables that describe the flow field, such as the structure of the flow pattern and the flow complexity. CONCLUSIONS: Although relatively large differences were found for all evaluated quantitative hemodynamic variables, the main flow characteristics were reproduced across imaging modalities.


Asunto(s)
Angiografía Cerebral/métodos , Circulación Cerebrovascular , Aneurisma Intracraneal/diagnóstico por imagen , Aneurisma Intracraneal/fisiopatología , Modelos Cardiovasculares , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Velocidad del Flujo Sanguíneo , Simulación por Computador , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Rotación , Sensibilidad y Especificidad
17.
Med Phys ; 37(11): 5711-27, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21158283

RESUMEN

PURPOSE: Computed tomography angiography (CTA) is often used to determine the degree of stenosis in patients that suffer from carotid artery occlusive disease. Accurate and precise measurements of the diameter of the stenosed internal carotid artery are required to make decisions on treatment of the patient. However, the inherent blurring of images hampers a straightforward measurement, especially for smaller vessels. The authors propose a model-based approach to perform diameter measurements in which explicit allowance is made for the blurring of structures in the images. Three features of the authors' approach are the use of prior knowledge in the fitting of the model at the site of the stenosis, the applicability to vessels both with circular and noncircular cross-section, and the ability to deal with additional structures close to the arteries such as calcifications. METHODS: Noncircular cross-sections of vessels were modeled with elliptic Fourier descriptors. When calcifications or other high-intensity structures are adjacent to the lumen, both the lumen and the high-intensity structures were modeled in order to improve the diameter estimates of the vessel. Measurements were performed in CT scans of a phantom mimicking stenosed carotids and in CTA scans of two patients with an internal carotid stenosis. In an attempt to validate the measurements in CTA images, measurements were also performed in three-dimensional rotational angiography (3DRA) images of the same patients. RESULTS: The validity of the approach for diameter measurements of cylindrical arteries in CTA images is evident from phantom measurements. When prior knowledge about the enhancement and the blurring parameter was used, accurate and precise diameter estimates were obtained down to a diameter of 0.4 mm. The potential of the presented approach, both with respect to the extension to noncircular cross-sections and the modeling of adjacent calcifications, appears from the patient data. The accuracy of the size estimates in the patient images could not be unambiguously established because no gold standard was available and the quality of the 3DRA images was often suboptimal. CONCLUSIONS: The authors have shown that the inclusion of a priori information results in accurate and precise diameter measurements of arteries with a small diameter. Furthermore, in patient data, the assumption of a circular cross-section often appears to be too simple. The extension to noncircular cross-sections and adjacent calcifications paves the way to realistic modeling of the carotid artery.


Asunto(s)
Angiografía/métodos , Arteria Carótida Interna/diagnóstico por imagen , Arteria Carótida Interna/patología , Tomografía Computarizada por Rayos X/métodos , Estenosis Carotídea/diagnóstico por imagen , Estenosis Carotídea/patología , Constricción Patológica , Análisis de Fourier , Humanos , Procesamiento de Imagen Asistido por Computador , Imagenología Tridimensional , Modelos Estadísticos , Modelos Teóricos , Fantasmas de Imagen , Reproducibilidad de los Resultados
18.
Burns ; 35(8): 1071-9, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19520515

RESUMEN

The population of elderly patients is expected to rise continuously over the next decades due to global demographic changes. The elderly seem to be most vulnerable to burns and their management remains undoubtedly a challenge. A clear age margin for elderly patients is not yet defined, but most studies adhere to the inclusion of patients 65 years and above, but the general condition and social situation must be taken into account. The understanding of the physiological basis of aging and its related pathophysiological changes has only marginally influenced treatment and decision making in elderly burn patients. When looking at treatment regimens currently applied in elderly burn patients, the discussion of standards in intensive care as well as surgical strategies is ongoing. However, trends towards a moderate, non-aggressive resuscitation approach and careful inclusion of key parameters like physiological age, pre-burn functional status and premorbid conditions, seem to be useful guidelines for interdisciplinary treatment decisions. Once ordered for surgical treatment, the amount of body surface area operated in one session should be adapted to the general status of the patient. Even if older burn victims have a reported higher mortality rate than younger patients, improved therapeutic options have contributed to a reduced mortality rate even in the elderly over the last decades. As a result of improved outcome, more attention has to be given to a comprehensive rehabilitation program. This review will give an overview of the current literature and will draw attention to specific topics related to this important subpopulation of burn patients.


Asunto(s)
Quemaduras/terapia , Accidentes Domésticos , Factores de Edad , Anciano , Envejecimiento/fisiología , Quemaduras/etiología , Quemaduras/mortalidad , Quemaduras/fisiopatología , Comorbilidad , Femenino , Humanos , Masculino , Factores Sexuales
19.
Med Phys ; 36(4): 1074-85, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19472612

RESUMEN

CT perfusion (CTP) examinations of the brain are performed increasingly for the evaluation of cerebral blood flow in patients with stroke and vasospasm after subarachnoid hemorrhage. Of the same patient often also a CT angiography (CTA) examination is performed. This study investigates the possibility to obtain CTA images from the CTP examination, thereby possibly obviating the CTA examination. This would save the patient exposure to radiation, contrast, and time. Each CTP frame is a CTA image with a varying amount of contrast enhancement and with high noise. To improve the contrast-to-noise ratio (CNR) we combined all 3D images into one 3D image after registration to correct for patient motion between time frames. Image combination consists of weighted averaging in which the weighting factor of each frame is proportional to the arterial contrast. It can be shown that the arterial CNR is maximized in this procedure. An additional advantage of the use of the time series of CTP images is that automatic differentiation between arteries and veins is possible. This feature was used to mask veins in the resulting 3D images to enhance visibility of arteries in maximum intensity projection (MIP) images. With a Philips Brilliance 64 CT scanner (64 x 0.625 mm) CTP examinations of eight patients were performed on 80 mm of brain using the toggling table technique. The CTP examination consisted of a time series of 15 3D images (2 x 64 x 0.625 mm; 80 kV; 150 mAs each) with an interval of 4 s. The authors measured the CNR in images obtained with weighted averaging, images obtained with plain averaging, and images with maximal arterial enhancement. The authors also compared CNR and quality of the images with that of regular CTA examinations and examined the effectiveness of automatic vein masking in MIP images. The CNR of the weighted averaged images is, on the average, 1.73 times the CNR of an image at maximal arterial enhancement in the CTP series, where the use of plain averaging increases the CNR only with a factor of 1.49. The quality of the weighted averaged images approaches that of CTA images, although in the present study the image quality of CTA was not quite reached. The automatic masking of veins is effective and only small remnants of veins were sometimes present in the masked images. Weighted averaging makes it possible to create CTA images from a CTP examination with a CNR considerably higher than that of images with maximal arterial enhancement. The quality of the resulting images approaches that of CTA images and offers the additional advantages to automatically differentiate between arteries and veins.


Asunto(s)
Encéfalo/patología , Angiografía Cerebral/métodos , Tomografía Computarizada por Rayos X/métodos , Algoritmos , Automatización , Huesos/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Angiografía Cerebral/instrumentación , Diseño de Equipo , Humanos , Procesamiento de Imagen Asistido por Computador , Imagenología Tridimensional , Modelos Estadísticos , Perfusión , Reproducibilidad de los Resultados , Factores de Tiempo , Venas/patología
20.
AJNR Am J Neuroradiol ; 29(1): 134-9, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17928381

RESUMEN

BACKGROUND AND PURPOSE: Our aim was to determine the diagnostic accuracy of multisection CT angiography combined with matched mask bone elimination (CTA-MMBE) for detection of intracranial aneurysms compared with digital subtraction angiography (DSA) and 3D rotational angiography (3DRA). MATERIALS AND METHODS: Between January 2004 and February 2006, 108 patients who presented with clinically suspected subarachnoid hemorrhage underwent both CTA-MMBE and DSA for diagnosis of an intracranial aneurysm. Two neuroradiologists, independently, evaluated 27 predefined vessel locations in the CTA-MMBE images for the presence of an aneurysm. After consensus, diagnostic accuracy of CTA was calculated per predefined location and per patient. Interobserver agreement was calculated with kappa statistics. RESULTS: In 88 patients (81%), 117 aneurysms (82 ruptured, 35 unruptured) were present on DSA. CTA-MMBE detected all ruptured aneurysms except 1. Overall specificity, sensitivity, positive predictive value, and negative predictive value of CTA-MMBE were 0.99, 0.90, 0.98, and 0.95 per patient and 0.91, 1.00, 0.97, and 0.99 per location, respectively. Sensitivity was 0.99 for aneurysms >/=3 mm and 0.38 for aneurysms <3 mm. Interobserver agreement for aneurysm detection was excellent (kappa value of 0.92 per location and 0.80 per patient). CONCLUSION: CTA-MMBE is accurate in detecting intracranial aneurysms in any projection without overprojecting bone. CTA-MMBE has limited sensitivity in detecting very small aneurysms. Our data suggest that DSA and 3DRA can be limited to the vessel harboring the ruptured aneurysm before endovascular treatment, after detection of a ruptured aneurysm with CTA.


Asunto(s)
Angiografía de Substracción Digital/métodos , Angiografía Cerebral/métodos , Imagenología Tridimensional/métodos , Aneurisma Intracraneal/diagnóstico por imagen , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Cráneo/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Anciano de 80 o más Años , Algoritmos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Intensificación de Imagen Radiográfica/métodos , Reproducibilidad de los Resultados , Rotación , Sensibilidad y Especificidad , Técnica de Sustracción
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