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1.
Orphanet J Rare Dis ; 14(1): 276, 2019 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-31791368

RESUMO

BACKGROUND: Inherited muscle diseases are a group of rare heterogeneous muscle conditions with great impact on quality of life, for which variable prevalence has previously been reported, probably due to case selection bias. The aim of this study is to estimate the overall and selective prevalence rates of inherited muscle diseases in a northern Spanish region and to describe their demographic and genetic features. Retrospective identification of patients with inherited muscle diseases between 2000 and 2015 from multiple data sources. Demographic and molecular data were registered. RESULTS: On January 1, 2016, the overall prevalence of inherited muscle diseases was 59.00/ 100,000 inhabitants (CI 95%; 53.35-65.26). Prevalence was significantly greater in men (67.33/100,000) in comparison to women (50.80/100,000) (p = 0.006). The highest value was seen in the age range between 45 and 54 (91.32/100,000) years. Myotonic dystrophy type 1 was the most common condition (35.90/100,000), followed by facioscapulohumeral muscular dystrophy (5.15/100,000) and limb-girdle muscular dystrophy type 2A (2.5/100,000). CONCLUSIONS: Prevalence of inherited muscle diseases in Navarre is high in comparison with the data reported for other geographical regions. Standard procedures and analyses of multiple data sources are needed for epidemiological studies of this heterogeneous group of diseases.

2.
Phys Med Biol ; 64(22): 225011, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31665703

RESUMO

Respiratory motion management techniques in radiotherapy (RT) planning are primarily focused on maintaining tumor target coverage. An inadequately addressed need is accounting for motion in dosimetric estimations in smaller serial structures. Accurate dose estimations in such structures are more sensitive to motion because respiration can cause them to move completely in or out of a high dose-gradient field. In this work, we study three motion management strategies (m1-m3) to find an accurate method to estimate the dosimetry in airways. To validate these methods, we generated a 'ground truth' digital breathing model based on a 4DCT scan from a lung stereotactic ablative radiotherapy (SAbR) patient. We simulated 225 breathing cycles with ±10% perturbations in amplitude, respiratory period, and time per respiratory phase. A high-resolution breath-hold CT (BHCT) was also acquired and used with a research virtual bronchoscopy software to autosegment 239 airways. Contours for planning target volume (PTV) and organs at risk (OARs) were defined on the maximum intensity projection of the 4DCT (CTMIP) and transferred to the average of the 10 4DCT phases (CTAVG). To design the motion management methods, the RT plan was recreated using different images and structure definitions. Methods m1 and m2 recreated the plan using the CTAVG image. In method m1, airways were deformed to the CTAVG. In m2, airways were deformed to each of the 4DCT phases, and union structures were transferred onto the CTAVG. In m3, the RT plan was recreated on each of the 10 phases, and the dose distribution from each phase was deformed to the BHCT and summed. Dose errors (mean [min, max]) in airways were: m1: 21% (0.001%, 93%); m2: 45% (0.1%, 179%); and m3: 4% (0.006%, 14%). Our work suggests that accurate dose estimation in moving small serial structures requires customized motion management techniques (like m3 in this work) rather than current clinical and investigational approaches.

4.
Biochem Pharmacol ; 165: 221-229, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30904473

RESUMO

Polymyalgia rheumatica (PMR) is an inflammatory disease characterized by bilateral pain involving predominantly the shoulders and proximal aspects of the arms and less commonly the neck and the pelvic girdle. This review discusses briefly the main epidemiological data and clinical features of this condition. Especial attention is paid in the management of the disease. For this reason, both the classic management and the impact of new therapies are discussed in depth. In general, patients with PMR experience a rapid response to 12.5-25 mg/prednisone/day in less than a week. Patients with poor response to glucocorticoids or with relapsing disease require other therapies aimed mainly to spare glucocorticoids. Among them, methotrexate is the most commonly used. Nevertheless, different studies indicate that this agent yields only a modest effect. Biologic therapies against the main cytokines involved in the pathogenesis of the disease have been used in refractory patients. However, randomized controlled trials do not support the use of anti-tumor necrosis factor agents in PMR. In contrast, several case series and retrospective studies highlight the efficacy of the anti-interleukin-6 receptor tocilizumab in PMR. Nonetheless, controlled trials are needed to fully establish the beneficial effect of this agent. The potential favorable effect of the Janus-kinase inhibitors and new anti-interleukin-6 antagonists remains to be determined.

6.
J Rheumatol ; 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30442823

RESUMO

OBJECTIVE: To describe nailfold videocapillaroscopy (NVC) features of patients with antisynthetase syndrome (AS) and to investigate possible correlations with clinical and serological features of the disease. METHODS: We retrospectively analyzed NVC images of 190 patients with AS [females/males 3.63, mean age 49.7 ± 12.8 yrs, median disease duration 53.7 mos (interquartile range 82), 133 anti-Jo1 and 57 non-anti-Jo1-positive patients]. For each patient, we examined number of capillaries, giant capillaries, microhemorrhages, avascular areas, ramified capillaries, and the presence of systemic sclerosis (SSc)-like pattern. Finally, we correlated NVC features with clinical and serological findings of patients with AS. Concomitantly, a historical cohort of 75 patients with antinuclear antibody-negative primary Raynaud phenomenon (RP) and longterm followup was used as a control group (female/male ratio 4.13/1, mean age 53.9 ± 17.6 yrs) for NVC measures. RESULTS: NVC abnormalities were observed in 62.1% of AS patients compared with 29.3% of primary RP group (p < 0.001). An SSc-like pattern was detected in 67 patients (35.3%) and it was associated with anti-Jo1 antibodies (p = 0.002) and also with a longer disease duration (p = 0.004). Interestingly, there was no significant correlation between the presence of SSc-like pattern and RP, and only 47% of patients with SSc-like pattern had RP. CONCLUSION: NVC abnormalities are commonly observed in AS, independently from the occurrence of RP. The presence of an SSc-like pattern could allow identification of a more defined AS subtype, and prospective studies could confirm the association with clinical and serological features of AS.

7.
Rev Esp Salud Publica ; 922018 Nov 19.
Artigo em Espanhol | MEDLINE | ID: mdl-30442882

RESUMO

In 2012, the Spanish Rare Disease Registries Research Network (Spain-RDR) was consolidated with the aim of creating a Spanish population-based Rare Diseases Registry. In order to achieve this, each of the 17 Spanish Regions had to develop its own regional registry with a common agreed methodology. The Population-based Rare Disease Registry of Navarre was created in 2013 and, since then, its implementation is been carried out. Navarre assumed the agreed list within the Spanish Network, which included 934 codes of the International Classification of Diseases, 9th Revision, Clinical Modification. Initially, the main data source used to capture cases was the Assisted Morbidity Registry of Navarre, which includes the Minimum Basic Data Set of every regional hospital discharges (both public and private). Afterwards, new data sources were been added and ongoing validation studies of captured cases were been developed. Population-based rare diseases registries are fundamental for the study and quantification of this type of diseases since the classification and coding systems used in the current healthcare information systems are very nonspecific. The analysis and cross-referencing of data among multiple data sources is essential to maximize case detection capacity. Due to the low prevalence of these diseases, a high false positives rate among the detected cases greatly affects the estimation of epidemiological indicators, which makes it necessary to validate the cases by verifying the diagnoses.

8.
Arthritis Rheumatol ; 2018 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-30251476

RESUMO

OBJECTIVE: A genome-wide association study (GWAS) was conducted to shed light into the genetic background influencing the development of cardiovascular (CV) disease in patients diagnosed with rheumatoid arthritis (RA). METHODS: After quality control and imputation, a total of 6,308,944 polymorphisms across the whole genome were analysed in 2,989 RA patients from European origin. Data on subclinical atherosclerosis, obtained by carotid ultrasonography through assessment of carotid intima-media thickness (cIMT) and presence/absence of carotid plaques, were available for 1,355 individuals. RESULTS: A genetic variant of the RARB gene (rs116199914) was associated with cIMT values at the genome-wide level of significance (minor allele (G): beta (ß) coefficient=0.142, P=1.86E-08). Interestingly, rs116199914 overlapped with regulatory elements in tissues related to CV pathophysiology and immune cells. In addition, biological pathway enrichment and predictive protein-protein relationship analyses, including suggestive GWAS signals of potential relevance, revealed a functional enrichment of the collagen biosynthesis network related to the presence/absence of carotid plaques (GO:0032964, PFDR =4.01E-03). Furthermore, our data suggest a potential influence of the previously described candidate CV risk loci NFKB1, MSRA and ZC3HC1 (P=8.12E-04, P=5.94E-04 and P=2.46E-04, respectively). CONCLUSION: Our study strongly suggests that genetic variation within RARB contributes to the development of subclinical atherosclerosis in patients with RA. This article is protected by copyright. All rights reserved.

9.
Reumatol. clín. (Barc.) ; 14(1): 9-19, ene.-feb. 2018. tab
Artigo em Espanhol | IBECS | ID: ibc-170367

RESUMO

Objetivo. Establecer recomendaciones, basadas en la evidencia, sobre el uso de la ecografía (US) y la resonancia magnética (RM) en pacientes con artritis reumatoide (AR). Métodos. Las recomendaciones se consensuaron mediante metodología basada en grupos nominales. Un grupo de expertos (15 reumatólogos y 3 radiólogos) definió el alcance, usuarios, apartados del documento, posibles recomendaciones, revisiones sistemáticas a realizar (se utilizaron y actualizaron las revisiones de documentos de consenso previos de EULAR), y de la asignación de tareas. Los expertos delimitaron los apartados y redactaron las recomendaciones. El nivel de evidencia y grado de recomendación se realizó utilizando el sistema del Center for Evidence Based Medicine de Oxford. El grado de acuerdo se estableció mediante un Delphi a 2 rondas. Las recomendaciones se votaron según una escala de 1 (total desacuerdo) a 10 (total acuerdo), definiéndose el acuerdo como una puntuación ≥ 7 por al menos el 70% de los participantes. El documento completo fue revisado por los expertos y el proyecto coordinado por un metodólogo experto. Resultados. Se emitieron 20 recomendaciones que cubren: la validez de la US y RM para la detección de actividad y daño estructural, capacidad diagnóstica, predictora (de progresión de daño estructural, de brote de la enfermedad, respuesta al tratamiento, etc.), utilidad en la evaluación y monitorización de estos pacientes que están en tratamiento, y uso de la US como guía (para infiltraciones o biopsias). Conclusiones. Se presentan recomendaciones útiles para el manejo de la US y RM por los clínicos en pacientes con AR (AU)


Objective. To develop evidence-based recommendations on the use of ultrasound (US) and magnetic resonance imaging (MRI) in patients with rheumatoid arthritis (RA). Methods. Recommendations were generated following a nominal group technique. A panel of experts, consisting of 15 rheumatologists and 3 radiologists, was established in the first panel meeting to define the scope and purpose of the consensus document, as well as chapters, potential recommendations and systematic literature reviews (we used and updated those from previous EULAR documents). A first draft of recommendations and text was generated. Then, an electronic Delphi process (2 rounds) was carried out. Recommendations were voted from 1 (total disagreement) to 10 (total agreement). We defined agreement if at least 70% of experts voted ≥7. The level of evidence and grade or recommendation was assessed using the Oxford Centre for Evidence-based Medicine Levels of Evidence. The full text was circulated and reviewed by the panel. The consensus was coordinated by an expert methodologist. Results. A total of 20 recommendations were proposed. They include the validity of US and MRI regarding inflammation and damage detection, diagnosis, prediction (structural damage progression, flare, treatment response, etc.), monitoring and the use of US guided injections/biopsies. Conclusions. These recommendations will help clinicians use US and MRI in RA patients (AU)


Assuntos
Humanos , Artrite Reumatoide/diagnóstico por imagem , Ultrassonografia , Imagem por Ressonância Magnética , Padrões de Prática Médica/tendências , Revisão por Pares/métodos
10.
Reumatol. clín. (Barc.) ; 14(1): 27-35, ene.-feb. 2018. tab
Artigo em Espanhol | IBECS | ID: ibc-170369

RESUMO

Objetivo. Establecer recomendaciones, basadas en la evidencia, sobre el uso de la ecografía (US) y la resonancia magnética en pacientes con espondiloartritis, incluyendo la artritis psoriásica, y en la artritis idiopática juvenil. Métodos. Las recomendaciones se consensuaron mediante metodología basada en grupos nominales. Un grupo de expertos (15 reumatólogos y 3 radiólogos) definió el alcance, los usuarios, los apartados, las posibles recomendaciones y las revisiones sistemáticas a realizar (se utilizaron y actualizaron las revisiones de documentos de consenso de EULAR), y se asignaron tareas. Los expertos delimitaron los apartados y redactaron las recomendaciones. El nivel de evidencia y el grado de recomendación se establecieron utilizando el sistema del Centre for Evidence Based Medicine de Oxford, y el grado de acuerdo mediante Delphi a 2 rondas. Las recomendaciones se votaron según una escala de 1 (total desacuerdo) a 10 (total acuerdo), definiéndose el acuerdo como una puntuación≥7 por al menos el 70% de los participantes. El documento fue revisado por los expertos y el proyecto estuvo coordinado por un metodólogo experto. Resultados. Se emitieron 12 recomendaciones sobre la validez de la US y la resonancia magnética para la detección de actividad y daño estructural, capacidad diagnóstica, predictora (de progresión de daño estructural, brote de la enfermedad, respuesta al tratamiento, etc.), utilidad en la evaluación y monitorización del tratamiento, y uso de la US como guía (para infiltraciones, biopsias, etc.) en pacientes con espondiloartritis y artritis idiopática juvenil. Conclusiones. Se presentan unas recomendaciones útiles para el manejo de la US y la resonancia magnética por los clínicos en pacientes con espondiloartritis y artritis idiopática juvenil (AU)


Objective. To develop evidence-based recommendations on the use of ultrasound (US) and magnetic resonance imaging in patients with spondyloarthritis, including psoriatic arthritis, and juvenile idiopathic arthritis. Methods. Recommendations were generated following a nominal group technique. A panel of experts (15 rheumatologists and 3 radiologists) was established in the first panel meeting to define the scope and purpose of the consensus document, as well as chapters, potential recommendations and systematic literature reviews (we used and updated those from previous EULAR documents). A first draft of recommendations and text was generated. Then, an electronic Delphi process (2 rounds) was carried out. Recommendations were voted from 1 (total disagreement) to 10 (total agreement). We defined agreement if at least 70% of participants voted≥7. The level of evidence and grade or recommendation was assessed using the Oxford Centre for Evidence Based Medicine levels of evidence. The full text was circulated and reviewed by the panel. The consensus was coordinated by an expert methodologist. Results. A total of 12 recommendations were proposed for each disease. They include, along with explanations of the validity of US and magnetic resonance imaging regarding inflammation and damage detection, diagnosis, prediction (structural damage progression, flare, treatment response, etc.), monitoring and the use of US guided injections/biopsies. Conclusions. These recommendations will help clinicians use US and magnetic resonance imaging in patients with spondyloarthritis and juvenile idiopathic arthritis (AU)


Assuntos
Humanos , Espondilartrite/diagnóstico por imagem , Artrite Juvenil/diagnóstico por imagem , Artrite Psoriásica/diagnóstico por imagem , Padrões de Prática Médica , Ultrassonografia/métodos , Espectroscopia de Ressonância Magnética/métodos , Prática Clínica Baseada em Evidências/métodos
11.
Reumatol Clin ; 14(1): 9-19, 2018 Jan - Feb.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-28029551

RESUMO

OBJECTIVE: To develop evidence-based recommendations on the use of ultrasound (US) and magnetic resonance imaging (MRI) in patients with rheumatoid arthritis (RA). METHODS: Recommendations were generated following a nominal group technique. A panel of experts, consisting of 15 rheumatologists and 3 radiologists, was established in the first panel meeting to define the scope and purpose of the consensus document, as well as chapters, potential recommendations and systematic literature reviews (we used and updated those from previous EULAR documents). A first draft of recommendations and text was generated. Then, an electronic Delphi process (2 rounds) was carried out. Recommendations were voted from 1 (total disagreement) to 10 (total agreement). We defined agreement if at least 70% of experts voted ≥7. The level of evidence and grade or recommendation was assessed using the Oxford Centre for Evidence-based Medicine Levels of Evidence. The full text was circulated and reviewed by the panel. The consensus was coordinated by an expert methodologist. RESULTS: A total of 20 recommendations were proposed. They include the validity of US and MRI regarding inflammation and damage detection, diagnosis, prediction (structural damage progression, flare, treatment response, etc.), monitoring and the use of US guided injections/biopsies. CONCLUSIONS: These recommendations will help clinicians use US and MRI in RA patients.


Assuntos
Artrite Reumatoide/diagnóstico por imagem , Imagem por Ressonância Magnética , Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Técnica Delfos , Monitoramento de Medicamentos , Medicina Baseada em Evidências , Humanos , Ultrassonografia
12.
Reumatol Clin ; 14(1): 27-35, 2018 Jan - Feb.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-28277255

RESUMO

OBJECTIVE: To develop evidence-based recommendations on the use of ultrasound (US) and magnetic resonance imaging in patients with spondyloarthritis, including psoriatic arthritis, and juvenile idiopathic arthritis. METHODS: Recommendations were generated following a nominal group technique. A panel of experts (15 rheumatologists and 3 radiologists) was established in the first panel meeting to define the scope and purpose of the consensus document, as well as chapters, potential recommendations and systematic literature reviews (we used and updated those from previous EULAR documents). A first draft of recommendations and text was generated. Then, an electronic Delphi process (2 rounds) was carried out. Recommendations were voted from 1 (total disagreement) to 10 (total agreement). We defined agreement if at least 70% of participants voted≥7. The level of evidence and grade or recommendation was assessed using the Oxford Centre for Evidence Based Medicine levels of evidence. The full text was circulated and reviewed by the panel. The consensus was coordinated by an expert methodologist. RESULTS: A total of 12 recommendations were proposed for each disease. They include, along with explanations of the validity of US and magnetic resonance imaging regarding inflammation and damage detection, diagnosis, prediction (structural damage progression, flare, treatment response, etc.), monitoring and the use of US guided injections/biopsies. CONCLUSIONS: These recommendations will help clinicians use US and magnetic resonance imaging in patients with spondyloarthritis and juvenile idiopathic arthritis.


Assuntos
Artrite Juvenil/diagnóstico por imagem , Artrite Psoriásica/diagnóstico por imagem , Imagem por Ressonância Magnética , Espondilartrite/diagnóstico por imagem , Humanos , Ultrassonografia
13.
Artigo em Espanhol | IBECS | ID: ibc-177576

RESUMO

En 2012 se consolidó la Red Española de Registros de Enfermedades Raras para la Investigación (Spain-RDR) con el objetivo de crear un Registro poblacional español de Enfermedades Raras. Para conseguirlo, cada Comunidad Autónoma tenía que desarrollar su propio registro autonómico con una metodología común consensuada. El Registro Poblacional de Enfermedades Raras de Navarra se creó en 2013 y, desde entonces, se está desarrollando su implementación. Navarra asumió el listado consensuado dentro de la Red, que incluye 934 códigos de la 9ª revisión de la Clasificación Internacional de Enfermedades (modificación clínica). Inicialmente, la principal fuente de información utilizada para la captación de casos fue el Registro de Morbilidad Asistida de Navarra, que recoge el Conjunto Mínimo Básico de Datos de las altas hospitalarias (de centros públicos y privados) de la Comunidad Foral. Posteriormente se fueron añadiendo nuevas fuentes de información y desarrollando continuos estudios de validación de los casos captados. Los registros poblacionales de enfermedades raras son fundamentales para el estudio y cuantificación de este tipo de enfermedades ya que los sistemas de clasificación y codificación utilizados en los actuales sistemas de información sanitaria son muy inespecíficos. El análisis y cruce de datos entre múltiples fuentes es esencial para maximizar la capacidad de detección de casos. Al tratarse de enfermedades muy poco prevalentes, una tasa alta de falsos positivos entre los casos detectados afecta en gran medida la estimación de indicadores epidemiológicos, lo que hace necesario validar los casos verificando los diagnósticos


In 2012, the Spanish Rare Disease Registries Research Network (Spain-RDR) was consolidated with the aim of creating a Spanish population-based Rare Diseases Registry. In order to achieve this, each of the 17 Spanish Regions had to develop its own regional registry with a common agreed methodology. The Population-based Rare Disease Registry of Navarre was created in 2013 and, since then, its implementation is been carried out. Navarre assumed the agreed list within the Spanish Network, which included 934 codes of the International Classification of Diseases, 9th Revision, Clinical Modification. Initially, the main data source used to capture cases was the Assisted Morbidity Registry of Navarre, which includes the Minimum Basic Data Set of every regional hospital discharges (both public and private). Afterwards, new data sources were been added and ongoing validation studies of captured cases were been developed. Population-based rare diseases registries are fundamental for the study and quantification of this type of diseases since the classification and coding systems used in the current healthcare information systems are very nonspecific. The analysis and cross-referencing of data among multiple data sources is essential to maximize case detection capacity. Due to the low prevalence of these diseases, a high false positives rate among the detected cases greatly affects the estimation of epidemiological indicators, which makes it necessary to validate the cases by verifying the diagnoses


Assuntos
Humanos , Doenças Raras/epidemiologia , Registros de Doenças/estatística & dados numéricos , Dados Demográficos , Espanha/epidemiologia , Indicadores de Morbimortalidade , Doenças Raras/classificação , Reações Falso-Positivas
14.
Rev. neurol. (Ed. impr.) ; 65(8): 368-372, 16 oct., 2017. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-167464

RESUMO

Introducción. La afectación de la columna vertebral en la gota es una complicación extremadamente infrecuente. La dorsalgia y la cuadriplejía son algunas manifestaciones que se pueden presentar, aunque estos síntomas se ven con más frecuencia en otras patologías más prevalentes, como los tumores medulares. Caso clínico. Se presenta un caso inusual de compresión medular dorsal en D10-D11 causado por el depósito extradural de material tofáceo en una paciente de 52 años con gota tofácea crónica incontrolada. Además de un tratamiento médico intensivo, la paciente requirió cirugía (hemilaminectomía y descompresión medular) y rehabilitación posterior. La evolución general y neurológica fue satisfactoria (AU)


Introduction. Spine involvement in gout is an extremely uncommon complication. Dorsalgia and quadriplegia are some manifestations that may occur, although these symptoms are seen more frequently in other more prevalent pathologies, such as spinal tumors. Case report. We present an unusual case of thoracic spinal cord compression at T10-T11 level caused by the extradural deposit of tophaceous material in a 52-year-old woman with uncontrolled chronic tophaceous gout. In addition to intensive medical treatment, the patient required surgery (hemilaminectomy and spinal decompression) and subsequent rehabilitation. Overall and neurological evolution were satisfactory (AU)


Assuntos
Humanos , Feminino , Pessoa de Meia-Idade , Compressão da Medula Espinal/etiologia , Gota/complicações , Descompressão Cirúrgica/métodos , Laminectomia/métodos , Paraplegia/cirurgia , Compressão da Medula Espinal/cirurgia
15.
Med Phys ; 44(5): 1707-1717, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28207950

RESUMO

PURPOSE: We investigated the feasibility of using simpler methods than manual whole-organ volume-of-interest (VOI) definition to estimate the organ activity concentration in single photon emission computed tomography (SPECT) in cases where the activity in the organ can be assumed to be uniformly distributed on the scale of the voxel size. In particular, we investigated an anatomic region-of-interest (ROI) defined in a single transaxial slice, and a single sphere placed inside the organ boundaries. METHODS: The evaluation was carried out using Monte Carlo simulations based on patient indium 111 In pentetreotide SPECT and computed tomography (CT) images. We modeled constant activity concentrations in each organ, validating this assumption by comparing the distribution of voxel values inside the organ VOIs of the simulated data with the patient data. We simulated projection data corresponding to 100, 50, and 25% of the clinical count level to study the effects of noise level due to shortened acquisition time. Images were reconstructed using a previously validated quantitative SPECT reconstruction method. The evaluation was performed in terms of the accuracy and precision of the activity concentration estimates. RESULTS: The results demonstrated that the non-uniform image intensity observed in the reconstructed images in the organs with normal uptake was consistent with uniform activity concentration in the organs on the scale of the voxel size; observed non-uniformities in image intensity were due to a combination of partial-volume effects at the boundaries of the organ, artifacts in the reconstructed image due to collimator-detector response compensation, and noise. Using an ROI defined in a single transaxial slice produced similar biases compared to the three-dimensional (3D) whole-organ VOIs, provided that the transaxial slice was near the central plane of the organ and that the pixels from the organ boundaries were not included in the ROI. Although this slice method was sensitive to noise, biases were less than 10% for all the noise levels studied. The use of spherical VOIs was more sensitive to noise. The method was more accurate for larger spheres and larger organs such as the liver in comparison to the kidneys. Biases lower than 7% were found in the liver when using large enough spheres (radius ≥ 28 mm), regardless of the position, of the VOI inside the organ even with shortened acquisition times. The biases were more position-dependent for smaller organs. CONCLUSIONS: Both of the simpler methods provided suitable surrogates in terms of accuracy and precision. The results suggested that a spherical VOI was more appropriate for estimating the activity concentration in larger organs such as the liver, regardless of the position of the sphere inside the organ. Larger spheres resulted in better estimates. A single-slice ROI was more suitable for activity estimation in smaller organs such as the kidneys, providing that the transaxial slice selected was near the central plane of the organ and that voxels from the organ boundaries were excluded. Under those conditions, activity concentrations with biases lower than 5% were observed for all the studied count levels and coefficients of variation were less than 9% and 5% for the 25% and 100% count levels, respectively.


Assuntos
Método de Monte Carlo , Imagens de Fantasmas , Tomografia Computadorizada de Emissão de Fóton Único , Humanos , Tamanho do Órgão , Tomografia Computadorizada por Raios X
18.
Sci Rep ; 7: 40303, 2017 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-28059143

RESUMO

A genetic component influences the development of atherosclerosis in the general population and also in rheumatoid arthritis (RA). However, genetic polymorphisms associated with atherosclerosis in the general population are not always involved in the development of cardiovascular disease (CVD) in RA. Accordingly, a study in North-American RA patients did not show the association reported in the general population of coronary artery disease with a series of relevant polymorphisms (TCF21, LPA, HHIPL1, RASD1-PEMT, MRPS6, CYP17A1-CNNM2-NT5C2, SMG6-SRR, PHACTR1, WDR12 and COL4A1-COL4A2). In the present study, we assessed the potential association of these polymorphisms with CVD in Southern European RA patients. We also assessed if polymorphisms implicated in the increased risk of subclinical atherosclerosis in non-rheumatic Caucasians (ZHX2, PINX1, SLC17A4, LRIG1 and LDLR) may influence the risk for CVD in RA. 2,609 Spanish patients were genotyped by TaqMan assays. Subclinical atherosclerosis was determined in 1,258 of them by carotid ultrasonography (assessment of carotid intima media thickness and presence/absence of carotid plaques). No statistically significant differences were found when each polymorphism was assessed according to the presence/absence of cardiovascular events and subclinical atherosclerosis, after adjustment for potential confounder factors. Our results do not show an association between these 15 polymorphisms and atherosclerosis in RA.


Assuntos
Artrite Reumatoide/genética , Aterosclerose/complicações , Aterosclerose/genética , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/genética , Predisposição Genética para Doença , Polimorfismo de Nucleotídeo Único/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Espanha
19.
Med Clin (Barc) ; 148(3): e15-e16, 2017 02 09.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-28034446
20.
Clin Nucl Med ; 42(1): e16-e21, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27819858

RESUMO

OBJECTIVES: We aimed to determine the consistency of quantitative PET measurements of metabolic tumor volume (MTV) and intratumoral heterogeneity index for primary untreated pancreatic adenocarcinomas, when using dual-time point F-FDG PET/CT imaging. METHODS: This is an institutional review board-approved, retrospective study including 71 patients with pancreatic adenocarcinoma, who underwent dual-time point F-FDG PET/CT imaging, at approximately 1 hour (early) and 2 hours (delayed), after injection. Automated gradient-based and 50% SUVmax-threshold segmentation methods were used to assess the primary tumor MTV and metabolic intratumoral heterogeneity index, calculated as the area under cumulative SUV-volume histograms (AUC-CSH), with lower AUC-CHS indexes corresponding to higher degrees of tumor heterogeneity. We defined that more than a ±10% change in MTV or AUC-CSH, compared with baseline, as clinically significant. RESULTS: Seventy-one FDG-avid pancreatic tumors were identified, with an average tumor diameter of 3.4 ± 0.9 cm (range, 1.5-6.4 cm). Metabolic tumor volume values remained consistent between early and delayed imaging when using the gradient PET segmentation method (P = 0.086), whereas statistically significant change was seen when using 50% SUVmax-threshold segmentation (P < 0.001). A decrease in more than 10% change in MTV (% ΔMTV) was observed in 70.4% (50/71) tumors, and 7.0% (5/71) of the tumors showed an increase more than 10 % ΔMTV, when using the 50% SUVmax-threshold segmentation. AUC-CSH indexes showed statistically significant differences between early and delayed time points (P < 0.001), when using the gradient segmentation. AUC-CSH index decreased by 10% or greater in 40.8% (29/71) of the tumors. AUC-CSH index remained stable between early and delayed when using the 50% SUVmax-threshold segmentation (P = 0.148) with percentage of change of less than 10% for all tumors. CONCLUSIONS: Metabolic tumor volume was relatively stable between early and delayed time points when PET gradient segmentation was used but changed greater than 10% in 77.4% of the tumors at delayed time point when threshold segmentation was used. The tumor heterogeneity index (AUC-CSH) changed greater than 10% in 40.8% of tumors at delayed imaging, when gradient segmentation was used but remained stable when threshold segmentation was used. It is important to standardize uptake time and segmentation methods to use FDG PET MTV and heterogeneity index as imaging biomarkers.


Assuntos
Adenocarcinoma/diagnóstico por imagem , Neoplasias Pancreáticas/diagnóstico por imagem , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Feminino , Fluordesoxiglucose F18 , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Tomografia Computadorizada com Tomografia por Emissão de Pósitrons/métodos , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos , Estudos Retrospectivos , Carga Tumoral
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