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Magnetic resonance (MR) identification and grading of subjects with liver fibrosis and inflammation represents a clinical challenge. MR elastography plays a well-defined role in fibrosis estimation, but its use is not widely available in clinical settings. Given that liver MR is becoming the reference standard for fat and iron quantitation, there is a need to clarify whether there is any role for MR imaging in the concomitant evaluation of fibrosis and inflammation in this setting. This review summarizes the diagnostic estimations of different MR imaging parameters obtained from conventional non-contrast-enhanced multiple b values diffusion-weighted acquisitions, variable flip angles T1 relaxation maps and STIR images. Although some derived parameters have shown a significant correlation to histological scores, a small magnitude of effect with wide overlap across severity grades is the rule. Contrary to fat and iron quantification, the low precision and reproducibility of MR imaging metrics limits its clinical relevance in fibrosis and inflammation assessment. In a sequential clinical approach combining different methodologies, MR imaging has no applicability for ruling-out and low accuracy for ruling-in advanced fibrosis. Thereby, MR elastography remains as the only image method with high diagnostic accuracy for the detection of advanced fibrosis. Until date, inflammation remains in a gray zone where biopsy cannot be replaced, and further investigations are needed. The present review offers an in-depth discuss of the MR imaging diagnostic performance for the evaluation of liver fibrosis and inflammation, highlighting the need for scientific improvements.

The association of non-alcoholic fatty liver disease (NAFLD) with insulin resistance (IR) is well established, yet little is known of their possible relationship with intrahepatic iron and serum tumour necrosis factor (TNF)-α concentrations in adults without diabetes. Thus, this study looked at the relationship of intrahepatic iron and serum TNF-α with intrahepatic triglycerides and IR in non-diabetic adults.In this cross-sectional study of 104 healthy non-diabetic Caucasians, a quantitative magnetic resonance (MR) imaging T2 gradient-echo technique was used to measure hepatic iron, with 1H-MR spectroscopy used to measure hepatic triglycerides. HOMA-IR was calculated to determine IR.The prevalence of hepatic iron overload (HIOL) was 26.6% in individuals with NAFLD vs. 0% in those without. IR was present in 87.5% of subjects with both NAFLD and HIOL, in 45.4% of those with NAFLD but not HIOL, and in 4.5% of those with neither. HOMA-IR was positively correlated with hepatic triglycerides (r = 0.56, P 0.001) and hepatic iron (r = 0.52, P 0.001), whereas serum TNF-α concentrations correlated with intrahepatic triglyceride levels (r = 0.28, P 0.04), but not with intrahepatic iron. Hepatic triglycerides, serum TNF-α and age were the only significant determinants of IR in regression analyses.IR is closely associated with intrahepatic triglycerides and, to a lesser extent, intrahepatic iron, with some interplay between them. High serum TNF-α concentrations may contribute to the association between NAFLD and IR, while increased hepatic triglycerides appear to be a determinant of the development of HIOL in non-diabetic subjects without haemochromatosis.

[EN] Purpose: To determine if preoperative vascular heterogeneity of glioblastoma is predictive of overall survival of patients undergoing standard-of-care treatment by using an unsupervised multiparametric perfusion-based habitat-discovery algorithm. Materials and Methods: Preoperative magnetic resonance (MR) imaging including dynamic susceptibility-weighted contrast material-enhanced perfusion studies in 50 consecutive patients with glioblastoma were retrieved. Perfusion parameters of glioblastoma were analyzed and used to automatically draw four reproducible habitats that describe the tumor vascular heterogeneity: high-angiogenic and low-angiogenic regions of the enhancing tumor, potentially tumor-infiltrated peripheral edema, and vasogenic edema. Kaplan-Meier and Cox proportional hazard analyses were conducted to assess the prognostic potential of the hemodynamic tissue signature to predict patient survival. Results: Cox regression analysis yielded a significant correlation between patients' survival and maximum relative cerebral blood volume (rCBV(max)) and maximum relative cerebral blood flow (rCBF(max)) in high-angiogenic and low-angiogenic habitats (P < .01, false discovery rate-corrected P < .05). Moreover, rCBF(max) in the potentially tumor-infiltrated peripheral edema habitat was also significantly correlated (P < .05, false discovery rate-corrected P < .05). Kaplan-Meier analysis demonstrated significant differences between the observed survival of populations divided according to the median of the rCBV(max) or rCBF(max) at the high-angiogenic and low-angiogenic habitats (log-rank test P < .05, false discovery rate-corrected P < .05), with an average survival increase of 230 days. Conclusion: Preoperative perfusion heterogeneity contains relevant information about overall survival in patients who undergo standard-of-care treatment. The hemodynamic tissue signature method automatically describes this heterogeneity, providing a set of vascular habitats with high prognostic capabilities., Study supported by H2020 European Institute of Innovation and Technology (POC-2016.SPAIN-07) and Universitat Politecnica de Valencia (PAID-10-14). J.J.A., E.F.G., and J.M.G.G. supported by Secretaria de Estado de Investigacion, Desarrollo e Innovacion (DPI2016-80054-R, TIN2013-43457-R). E.F.G. supported by CaixaImpulse program from Fundacio Bancaria "la Caixa" (LCF/TR/CI16/10010016). E.F.G and A.A.B. supported by the Universitat Politecnica de Valencia Instituto Investigacion Sanitaria de La Fe (C05).

Resumen Objetivo Nuestro objetivo fue analizar el rendimiento de la biopsia selectiva del ganglio centinela valorando la deteccion gammagrafica tras la administracion intratumoral del radiofarmaco en pacientes con cancer de mama que recibieron quimioterapia neoadyuvante. Material y metodos Sesenta pacientes con diagnostico de carcinoma infiltrante de mama, estadios T1-T3, que recibieron tratamiento con quimioterapia neoadyuvante fueron sometidas posteriormente a cirugia mamaria y biopsia del ganglio centinela mediante administracion intratumoral del radiofarmaco. Resultados Se consiguio la deteccion gammagrafica de algun ganglio centinela en 55/60 pacientes (91,6%). Cuando se excluyeron los casos con reinyeccion periareolar del radiofarmaco por falta de migracion, la deteccion fue del 70% (42/60). Cuando se comparo la deteccion o no del ganglio centinela en estas 42 pacientes, no se encontraron diferencias en funcion de la edad, lateralidad-localizacion de la lesion, tamano pre y posquimioterapia, grado histologico del tumor o perfil inmunohistoquimico. Si existieron diferencias significativas al comparar los grupos segun el grado de respuesta patologica del tumor, valorado tanto con el sistema de Miller-Payne (no deteccion 44,4%-deteccion 16,7%, p = 0,003) como con el sistema residual cancer burden (72,2%-28,6%, p Conclusiones La deteccion gammagrafica del ganglio centinela tras administracion intratumoral del radiofarmaco en pacientes con cancer de mama que recibieron quimioterapia neoadyuvante estuvo por debajo del valor optimo, siendo necesaria en ocasiones la reinyeccion periareolar, lo que podria estar en relacion con una alteracion de las vias de drenaje linfatico. Existio una significativa relacion inversa entre deteccion del ganglio centinela y el grado de respuesta patologica tumoral.

espanolObjetivos Comparar los resultados de la dosimetria individual en pacientes de cancer diferenciado de tiroides tratados con 131I en nuestro centro con los limites dosimetricos establecidos y con resultados obtenidos en estudios publicados. Analizar el numero optimo de medidas a realizar para reducir el impacto de la dosimetria en el bienestar del paciente y, en segundo termino, en la carga de trabajo del personal sanitario. Material y metodos Se realiza la dosimetria a 29 pacientes del Servicio de Medicina Nuclear del Hospital Universitario y Politecnico La Fe, afectados de cancer diferenciado de tiroides y tratados con actividades de entre 1,02 y 5,51 GBq (promedio de 2,68 GBq) de 131I. Para ello se utiliza el protocolo de la Sociedad Espanola de Fisica Medica (SEFM) basado en medidas de tasa de dosis externa ajustadas a una curva biexponencial, de acuerdo con un modelo de dos compartimentos. Para cada paciente se realizan distintas dosimetrias tomando diferentes selecciones de las medidas disponibles a fin de buscar el numero optimo. Resultados Los resultados estan muy por debajo de los limites dosimetricos y son coherentes con los obtenidos en otros centros. El numero de medidas puede reducirse de 5, como propone el protocolo de la SEFM, a 4 sin perdida de precision significativa. Una mayor reduccion de medidas puede justificarse en casos particulares. Conclusiones Los valores obtenidos para las magnitudes dosimetricas quedan muy por debajo de los limites establecidos. Se puede asumir la reduccion de medidas a costa de un aumento de la incertidumbre moderado beneficiando del paciente. EnglishObjectives To compare the results of individual dosimetry in differentiated thyroid cancer patients treated with 131I at our centre with the established limits and dosimetry results of published studies. Analysis of the optimal number of measurements necessary to reduce the impact of dosimetry for the comfort of the patient and, secondly, on the workload of health workers. Material and methods Dosimetry was performed in the Nuclear Medicine Department of the University and Polytechnic Hospital La Fe, on 29 patients suffering from differentiated thyroid cancer and treated with activities between 1.02 and 5.51 GBq (mean 2.68 GBq) of 131I. The Spanish Society of Medical Physics (SEFM) protocol was used, based on measurements of external dose rate adjusted to a bi-exponential curve according to a two compartment model. Different dosimetries were performed on each patient, taking different selections of the available measurements in order to find the optimal number. Results Results are well below the dosimetry limits, and are consistent with those obtained in other centres. The number of measurements can be reduced from 5, as proposed in the SEFM protocol, to 4 without significant loss of accuracy. Further reducing measures may be justified in individual cases. Conclusions The values obtained for the dosimetry quantities are significantly below the established limits. A reduction in measurements can be assumed at the cost of a moderate increase in uncertainty, benefiting the patient.

Several pathological conditions carry high risk of bone fracture which is associated to high economic and healthy costs. In order to improve understanding the bone microarchitecture, this work aims to evaluate the accuracy of the bone analysis methodology and compare it to the reference standard under different imaging modalities. The results indicate that there is a good relation between the analysis of the bone analysis methodology obtained from the MDCT and MR scans and these modalities can be used for bone quality assessment in clinical practice.

Imaging biomarkers describe objective characteristics that are related to normal biological processes, diseases, or the response to treatment. They enable radiologists to incorporate into their reports data about structure, function, and tissue components. With the aim of taking maximum advantage of the quantification of medical images, we present a procedure to integrate imaging biomarkers into radiological reports, bringing the new paradigm of personal medicine closer to radiological workflow. In this manner, the results of quantification can complement traditional radiological diagnosis, improving accuracy and the evaluation of the efficacy of treatments. A more personalized, standardized, structured radiological report should include quantitative analyses to complement conventional qualitative reporting in selected cases.

SummaryBackground: Radiology reports are commonly written on free-text using voice recognition devices. Structured reports (SR) have a high potential but they are usually considered more difficult to fill-in so their adoption in clinical practice leads to a lower efficiency. However, some studies have demonstrated that in some cases, producing SRs may require shorter time than plain-text ones. This work focuses on the definition and demonstration of a methodology to evaluate the productivity of software tools for producing radiology reports. A set of SRs for breast cancer diagnosis based on BI-RADS have been developed using this method. An analysis of their efficiency with respect to free-text reports has been performed.Material and Methods: The methodology proposed compares the Elapsed Time (ET) on a set of radiological reports. Free-text reports are produced with the speech recognition devices used in the clinical practice. Structured reports are generated using a web application generated with TRENCADIS framework. A team of six radiologists with three different levels of experience in the breast cancer diagnosis was recruited. These radiologists performed the evaluation, each one introducing 50 reports for mammography, 50 for ultrasound scan and 50 for MRI using both approaches. Also, the Relative Efficiency (REF) was computed for each report, dividing the ET of both methods. We applied the T-Student (T-S) test to compare the ETs and the ANOVA test to compare the REFs. Both tests were computed using the SPSS software.Results: The study produced three DICOM- SR templates for Breast Cancer Diagnosis on mammography, ultrasound and MRI, using RADLEX terms based on BIRADs 5th edition. The T-S test on radiologists with high or intermediate profile, showed that the difference between the ET was only statistically significant for mammography and ultrasound. The ANOVA test performed grouping the REF by modalities, indicated that there were no significant differences between mammograms and ultrasound scans, but both have significant statistical differences with MRI. The ANOVA test of the REF for each modality, indicated that there were only significant differences in Mammography (ANOVA p = 0.024) and Ultrasound (ANOVA p = 0.008). The ANOVA test for each radiologist profile, indicated that there were significant differences on the high profile (ANOVA p = 0.028) and medium (ANOVA p=0.045).Conclusions: In this work, we have defined and demonstrated a methodology to evaluate the productivity of software tools for producing radiology reports in Breast Cancer. We have evaluated that adopting Structured Reporting in mammography and ultrasound studies in breast cancer diagnosis improves the performance in producing reports.

Purpose: Our objective was to analyse the accuracy of the sentinel node biopsy, taking into consideration the scintigraphy detection rate after the intratumoural administration of the radiopharmaceutical in patients with breast cancer who received neoadjuvant chemotherapy. Materials and methods: The study included 60 patients with a diagnosis of invasive breast carcinoma, stage T1-T3, who received treatment with neoadjuvant chemotherapy, and were subsequently subjected to breast surgery and sentinel node biopsy after intra-tumour administration of the radiopharmaceutical. Results: Scintigraphic detection of some sentinel node was achieved in 55/60 patients (91.6%). When those cases that received a second injection of the radiopharmaceutical, performed peri-areolarly due to a lack of tracer migration, were excluded, the detection rate dropped to 70% (42/60). When the detection of sentinel node, or its absence, was compared in those 42 patients, no differences were found with age, laterality-location of the lesion, size pre- and post-neoadjuvant chemotherapy, histological grade, or immunohistochemical profile. There were significant differences when comparing the groups according to the degree of pathological tumour response, both with the Miller-Payne system (non-detection 44.4%-detection 16.7%, p = 0.003) as well as the residual cancer burden (72.2%-28.6%, p

Imaging biomarkers define objective characteristics extracted from medical images that are related to normal biological processes, diseases, or the response to treatment. To develop an imaging biomarker, it is necessary to carry out a series of steps to validate its relation with the reality studied and to check its clinical and technical validity. This process includes defining tests for the concepts and mechanisms; obtaining standardized and optimized anatomic, functional, and molecular images; analyzing the data with computer models; displaying data appropriately; obtaining the appropriate statistic measures; and conducting tests on the principle, efficacy, and effectiveness. In this article, we aim to explain the steps that must be established to enable biomarkers to be correctly applied, from their theoretical conception to their clinical implementation. To this end, we use the evaluation of angiogenesis in articular cartilage as an example.

Imaging biomarkers define objective characteristics extracted from medical images that are related to normal biological processes, diseases, or the response to treatment. To develop an imaging biomarker, it is necessary to carry out a series of steps to validate its relation with the reality studied and to check its clinical and technical validity. This process includes defining tests for the concepts and mechanisms; obtaining standardized and optimized anatomic, functional, and molecular images; analyzing the data with computer models; displaying data appropriately; obtaining the appropriate statistic measures; and conducting tests on the principle, efficacy, and effectiveness. In this article, we aim to explain the steps that must be established to enable biomarkers to be correctly applied, from their theoretical conception to their clinical implementation. To this end, we use the evaluation of angiogenesis in articular cartilage as an example.

Brain connectivity is a key concept for understanding brain function. Current methods to detect and quantify different types of connectivity with neuroimaging techniques are fundamental for understanding the pathophysiology of many neurologic and psychiatric disorders. This article aims to present a critical review of the magnetic resonance imaging techniques used to measure brain connectivity within the context of the Human Connectome Project. We review techniques used to measure: a) structural connectivity b) functional connectivity (main component analysis, independent component analysis, seed voxel, meta-analysis), and c) effective connectivity (psychophysiological interactions, causal dynamic models, multivariate autoregressive models, and structural equation models). These three approaches make it possible to combine and use different statistical techniques to elaborate mathematical models in the attempt to understand the functioning of the brain. The findings obtained with these techniques must be validated by other techniques for analyzing structural and functional connectivity. This information is integrated in the Human Connectome Project where all these approaches converge to provide a representation of all the different models of connectivity.

Objectives. To classify the tumor areas in patients with grade IV astrocytoma by calculating and statistically analyzing quantitative MRI perfusion parameters. Material and methods. We applied two models of MRI perfusion, the unicompartmental and the pharmacokinetic models, in 15 patients diagnosed with grade IV astrocytoma. In the unicompartmental model, we quantified cerebral blood volume (CBV), mean transit time (MTT), and cerebral blood flow (CBF). In the pharmacokinetic model, we measured the permeability constant (Ktrans), the extraction coefficient (kep), the fraction of the volume in the interstitial space (ve), the fraction of the volume in the vessels (vp), the permeability in the first pass (Kfp), and the vascular volume in the first pass (vpfp). For each parameter, histograms were obtained for the total tumor area, for the peritumoral area, and for the healthy tissue. The statistical analysis included an analysis of variance for each parameter and a discriminant analysis. Results. The most significant differences between the regions were obtained with CBV, CBF, Ktrans, and vpfp; of these, CBV had the best results. The best classificatory function on the discriminant analysis was the combination of Ktrans and CBV. The analysis of the shape of the histogram showed statistically significant differences for the kurtosis of Ktrans and kep, as well as for the skewness of CBV, CBF, Ktrans, and vpfp. Conclusion. When parameters are considered individually, CBV is the one that best enables differentiation between tumor, peritumoral, and healthy tissue. The classificatory function generated from CBV and Ktrans results in improved classification by areas.

Objectives To study the viability of longitudinal relaxation time ( T1 ) of patellar cartilage as a biomarker of the degree of degeneration. Material and methods We included 15 subjects classified into three groups according to clinical criteria (pain, functional limitation, and duration of symptoms) and imaging criteria as follows: (a) normal (3 men, 2 women; age 30 ± 14 years), (b) with initial degeneration of the patellar cartilage (3 men, 2 women; age 30 ± 6 years), or (c) with advanced degeneration (3 men, 2 women; age 57 ± 10 years). All underwent MRI examination using special echo-gradient sequences to segment the cartilage and calculate the T1 maps. We selected the entire cartilage and the regions of interest classified according to clinical and imaging criteria as normal, initial degeneration, and advanced degeneration. The T1 values of the cartilage were obtained pixel by pixel and were calculated as the mean for the entire cartilage or by subregions (normal, initial, advanced). Differences between groups for the entire cartilage and the regions were analyzed using Student-Newman-Keuls post-hoc ANOVA. Reproducibility was evaluated using the coefficient of variance. Results No significant differences in the overall analysis of the entire cartilage were found between the three groups (normal: 1003 ± 172 ms, initial: 1064 ± 124 ms, advanced: 1041 ± 308 ms, p = 0.665). However, the analysis by regions revealed significant differences (normal: 908 ± 53 ms, initial degeneration: 1057 ± 157 ms, advanced degeneration: 1133 ± 116 ms, p = 0.029). The reproducibility analysis found variations of 1.3% for the overall calculation, 3.7% for the regional calculation, and 8.2% for the acquisition. Conclusion In this preliminary study, calculating the T1 of the cartilage enabled regions with different degrees of degeneration to be differentiated.

This article reviews the regulations in force about the exposure of workers to the electromagnetic fields generated by magnetic resonance imaging (MRI) and evaluates the impact of European Directive 2004/40/EC on the daily use of MRI. We provide a detailed review of the safety criteria stipulated in the International Commission on Non-Ionizing Radiation Protection, in Spanish Royal Decree 1066/2001, and in European Directive 2004/40/EC about exposure to electromagnetic fields. In the case of European Directive 2004/40/EC, the European Union (EU) has introduced a law without adequately evaluating its repercussions. In response to alarms sounded by the radiological and general medical communities, the EU has decided to delay implementation of the Directive. Although the implementation of Directive 2004/40/ EC has been postponed until April 30, 2012, it remains in force. There remains the hope that the Directive will be reconsidered during this interval and that MRI workers will be exempt.

The tough [correction of turf] battles with other specialties that tend to take control of the radiological practice and some of our areas of interest are one of the most important problems that Radiology must face at the present time. Interventional Radiology is the last one and the more recent example of this phenomenon that spreads world-wide. Far from defeatist attitudes, we must learn from our past mistakes to turn this scenario into an opportunity to evolve towards a more competitive and updated specialty according to our time. The authors review the present situation of the tough [correction of turf] batlles of Radiology with other specialties, pointing to their possible causes and proposing the resolution strategies.

Object: Automatic accurate measurement techniques are needed to increase reproducibility in the quantification of cervical cord area (CCA) with magnetic resonance (MR) imaging in the assessment of central nervous system (CNS) atrophy in multiple sclerosis (MS) patients. Materials and methods: Two segmentation methods were implemented: (1) spatial mean brightness level estimation (SMBLE), and (2) partial-volume modeling (PVM). These were evaluated with the inclusion of spinal cord inclination and/or partial-volume-effect corrections. An averaged manually segmented set was considered as reference. Thirty MR studies were used to compare the different methods. A set of 15 MS patients and 15 control subjects within a two-year longitudinal study were used to evaluate cord atrophy with the best method. Statistical evaluation was made by using an intraclass correlation coefficient and Bland–Altman comparisons. Results: Partial-volume modeling with spinal cord inclination correction and partial-volume spinal-cord contour contribution estimation was the most accurate method. The longitudinal test showed a 4% decrease in CCA in MS patients with no significant reduction in control subjects. Conclusion: The automatic PVM cord-segmentation approach, taking into consideration the spinal-cord inclination and partial-volume treatment, provides reproducibility and increased accuracy in the evaluation of cord atrophy, allowing the monitoring of changes in MS patients.

Objetivo Analizar la distinta contribucion de las categorias jerarquicas en los articulos publicados por radiologos de hospitales pertenecientes a la Comunidad Valenciana en el periodo 1994-2001, asi como su distribucion en las revistas. Material y metodo Para la recuperacion de la muestra de articulos hemos disenado perfiles de busqueda especificos para las bases de datos IME y Medline. Se identifico la categoria jerarquica de los autores mediante entrevistas personales. Resultados Hemos analizado 417 trabajos, con 1.321 firmas distribuidas de la siguiente forma: jefe de servicio: 8,8%; jefe de seccion: 12,4%; adjunto: 50,7%, y residente: 28%. Las agrupaciones jerarquicas con participacion de residentes fueron las que firmaron de manera mas estable trabajos en todas las anualidades (1994-2001). El mayor porcentaje de firmas (21%) correspondio a la agrupacion «residentes + adjuntos». Radiologia fue la revista mas productiva (42% de los trabajos). Todos los resultados fueron estadisticamente significativos (p Conclusion Los residentes en radiodiagnostico de los hospitales de la Comunidad Valenciana mostraron una participacion activa en los articulos e investigacion publicados en el periodo 1994-2001, en colaboracion con el resto de las categorias jerarquicas, mas frecuentemente con adjuntos. La figura del adjunto aporto el mayor numero de firmas. El jefe de seccion y el jefe de servicio suponen, conjuntamente, la quinta parte de las firmas.

Resumen Objetivos Establecer las variables minimas para diagnosticar las lesiones de la boveda craneal con tomografia computarizada (TC) y comprobar la precision de la regresion logistica (RL) y las redes neuronales artificiales (RN) en su diagnostico. Material y Metodos Estudiamos 167 pacientes con lesiones de boveda craneal como unica manifestacion conocida de enfermedad. Los datos clinicos y de la TC se emplearon para los modelos de RL y RN, que se probaron con el metodo jacknife. Los resultados finales de cada modelo se compararon con el area bajo la curva ROC (A2). Resultados Las lesiones fueron en un 73,1 % benignas y 26,9% malignas. No hubo diferencia estadisticamente significativa entre la RL y la RN para diagnosticar las lesiones malignas. Para la caracterizacion de los diagnosticos histologicos, la RN fue estadisticamente superior a la RL. Las variables necesarias para el diagnostico de lesion maligna fueron la edad y la definicion de los bordes, y para los diagnosticos histologicos, matriz, esclerosis marginal y la edad. Conclusiones Se necesitan cuatro minimas variables para el diagnostico de estas lesiones, no siendo importante el tipo de sintomatologia. Las redes neuronales ofrecen grandes posibilidades sobre la estadistica para las lesiones de la boveda craneal ademas de un mejor rendimiento diagnostico.

Objetivo Valorar la prevalencia y describir los hallazgos de los quistes de Baker complicados observados en una serie larga de estudios de resonancia magnetica (RM) de rodilla. Material y metodos De una serie de 382 pacientes consecutivos con estudio de RM de rodilla se detectaron 145 (38%) quistes de Baker. Los quistes se clasificaron como simples (paredes lisas, contenido homogeneo, intensidad de senal semejante a la del liquido sinovial y sin alteraciones en los tejidos circundantes) o complicados (alteracion de las paredes, alteraciones de la intensidad de senal del contenido, presencia de cuerpos libres o alteraciones en los tejidos de alrededor). Se observaron complicaciones en 10 (6,9%) quistes, confirmadas mediante observacion directa (artroscopica o quirurgicamente, n = 9 casos) o por evidencia clinica con seguimiento (n = 1 caso). Resultados No se detectaron diferencias en la distribucion por sexos entre quistes simples y complicados (c2, p = 0,9), aunque si se evidencio una relacion estadisticamente significativa entre la existencia de complicaciones con una mayor edad del paciente (p = 0,003) y la presencia de lesiones meniscales (p = 0,019). En 5 pacientes se encontro rotura del quiste de Baker, en 4 cuerpos libres intraquisticos y en 1 caso se trataba de una sinovitis villonodular pigmentada con focos intraquisticos. De los 5 pacientes con rotura del quiste, solo 2 presentaron sintomas de tromboflebitis, siendo el resto de roturas asintomaticas. En 3 de los 4 pacientes con cuerpos libres intraquisticos, estos se consideraron secundarios a lesiones osteocondrales degenerativas, presentando el otro caso una condromatosis sinovial. Conclusion Los quistes de Baker son frecuentes y generalmente no presentan complicaciones asociadas. En nuestra serie se ha observado una prevalencia de un 6,8% de quistes complicados, bien por su contenido o por alteraciones en sus paredes. La complicacion mas frecuente es la rotura (50% de los quistes complicados), que puede ser asintomatica hasta en un 80% de los casos, seguida de cuerpos libres intraquisticos (40% de las complicaciones), usualmente de origen degenerativo. La complicacion se asocia estadisticamente a roturas meniscales y pacientes mayores.

There is no doubt that radiologists play an increasingly important role in the detection of focal liver lesions, and in the evaluation of persistent or recurrent malignant disease after treatment. The characterization of focal liver lesions depends on the clinical integration of the information generated by different radiologic techniques. Most often, MR imaging is quite effective in liver tumor characterization. Our purpose is to provide an overview of the MR characteristics of the most commonly encountered liver tumors and their differential diagnosis, with the most accepted reliable proof of the lesion type in a clinical environment. Radiologists must know the level of confidence they can reach in a given diagnosis, and the influence that this diagnosis has in the patient's management. With this knowledge, radiologists decide whether to leave or follow-up the lesion, perform tissue samples, or carry out therapeutic procedures.

Sedation is frequently required in children undergoing magnetic resonance imaging (MRI). 172 Paediatric patients (82 female and 90 male, age 42 +/- 26 months, weight 14.7 +/- 5.6 kg) entered an open, non-comparative, prospective study to assess the utilization of oral chloral hydrate. Chloral hydrate syrup (70 mg/ml) was administered 20-30 min prior to the procedure. Effective sedation was reached in 80.3% with an average initial dose of 55 mg/kg and in 93.6% with an average total dose of 65 mg/kg. Significant differences in effectivity were correlated with the dose (54 +/- 11 mg/kg in failure cases versus 66 +/- 16 mg/kg in effective cases; p < 0.05) and diagnosis (effectivity falls to 62.5% and 76.0% in children with medullar tumours and encephalic white matter alterations, respectively; p < 0.01). Average sleep induction time was 30 +/- 19 min, and average duration of sleep was 62 +/- 24 min. Adverse reactions occurred in 4.7%, with nausea, vomiting and stomach pain being the most common side-effects (3.5%). Multivariate statistical analysis selects total dose and age into the discriminant function, with a 100% relative percentage of correct classification. A simple method for optimizing the chloral hydrate dose in children is proposed: the dose in mg/kg is calculated as half the age in months + 50.

This paper introduces a novel distributed decision support system to help radiologists in the diagnosis of soft tissue tumors (STT). Decision support systems are based on pattern recognition engines that discriminate between benign/malignant character and histological groups with a satisfactory estimated efficiency. This system is based on a distributed architecture with three specialized nodes: Radiologist Visual Interface, Information System and Decision Support Web-services. The visual interface is the radiologists and clinicians' point of access to local and remote STT registers, statistical analysis tools and distributed pattern recognition engines. A location-independent and multi-platform system has been developed in order to connect hospitals and institutions to research useful tools in clinical and laboratory environments. The nodes maintenance and upgrade are automatically controlled by the architecture. This tool will be useful regarding the objective methodology to assist radiologist decision in a new case and will help the education of the new radiologists with no expertise in STT.

El secuestro pulmonar es una zona de tejido pulmonar, separada del arbol traqueobronquial, que recibe el aporte sanguineo de una arteria sistemica. El diagnostico requiere la comprobacion de los vasos anomalos mediante arteriografia. Sin embargo, con la resonancia magnetica (RM) es posible demostrar tanto las alteraciones del parenquima pulmonar como la vascularizacion aberrante en diversos planos, por lo que se puede obviar la necesidad de angiografia. Se describe un caso de secuestro pulmonar intralobar diagnosticado por RM y confirmado despues mediante arteriografia y en la intervencion quirurgica. Se comenta la aportacion de la RM y la angiografia por RM, no solo en el diagnostico, sino tambien en la evaluacion prequirurgica del secuestro pulmonar. Destaca sobre todo que se trata de maniobras no invasivas que no requieren la utilizacion de medio de contraste.

[ES] Introducción. Algunos estudios anteriores en pacientes con esquizofrenia han sugerido alteraciones morfométricas y funcionales en el colículo inferior. Las alucinaciones auditivas son uno de los síntomas centrales en la esquizofrenia. Se piensa que en este evento complejo y multidisciplinar, tanto la atención como la emoción desempeñan un papel clave. Objetivo. Estudiar los cambios metabólicos en el colículo inferior, un núcleo integrado en la vía auditiva, en pacientes con esquizofrenia y su posible relación con las alucinaciones auditivas. Sujetos y métodos. Se llevaron a cabo estudios de espectroscopía de resonancia magnética en 30 pacientes diestros con esquizofrenia crónica (19 de ellos con alucinaciones auditivas) y 28 controles. Se adquirió una secuencia 2D de espectroscopía de resonancia magnética y se seleccionaron los vóxeles representativos de ambos colículos inferiores. Se calculó el área de los picos de N-acetilaspartato (NAA), creatina (Cr) y colina (Co). Resultados. Los pacientes con esquizofrenia mostraron una reducción significativa de NAA/Cr en el colículo inferior derecho comparados con los sujetos control. Los datos metabólicos en el colículo inferior derecho se correlacionaron con los ítems emocionales de las alucinaciones auditivas. Conclusiones. La contribución del colículo inferior a las bases neuronales de las alucinaciones auditivas es particularmente relevante para el colículo inferior derecho y se centra en el componente atencional-emocional de este síntoma., [EN] Introduction. Previous studies have suggested morphometric and functional abnormalities in the inferior colliculus in patients with schizophrenia. Auditory hallucinations are one of the central symptoms in schizophrenia. In this complex and multidimensional event both attention and emotion are thought to play a key role. Aim. To study metabolic changes in the inferior colliculus, a nucleus integrated in the auditory pathway, in patients with schizophrenia and the possible relationship with auditory hallucinations. Subjects and methods. Magnetic resonance spectroscopic imaging studies were performed in 30 right-handed patients with chronic schizophrenia (19 of them with auditory hallucinations) and 28 controls. A magnetic resonance spectroscopic imaging 2D slice was acquired and the voxels representative of both inferior colliculi were selected. N-acetylaspartate (NAA), creatine (Cr) and choline (Cho) peak areas were measured. Results. The patients with schizophrenia showed a NAA/Cr significant reduction in the right inferior colliculus compared to the control subjects. The metabolic data in the right inferior colliculus were correlated with emotional auditory hallucinations items. Conclusions. The contribution of the inferior colliculus on neural underpinnings of auditory hallucinations is particularly relevant for the right inferior colliculus and is centered on attention-emotional component of this symptom., Subvención española SAF2007- 65473, Proyecto Europeo Integrado eTUMOUR (FP6-2002-LIFESCIHEALTH 503094) y proyecto MIND del CENIT.

Magnetic resonance (MR) field strength is one of the key aspects to consider when purchasing MR equipment. Other aspects include the gradient system, coil design, computer and pulse sequence availability, purchase cost, local reimbursement policies, and current opinion within the medical community. Our objective here is to evaluate the decision-influencing aspects of the MR market, with a focus on some specific areas such as high resolution studies, examination times, special techniques, instrumentation, open design magnets, costs and reimbursement policies, academic and industrial interests, contrast media, clinical efficacy, and finally, clinicians' preferences. Certainly the advantage of high-field is a higher signal-to-noise ratio and improved resolution. With a high-field unit, higher spatial resolution images and higher temporal resolution images can be obtained. Typical imaging times needed to produce clinically diagnostic images are about 3 times longer at 0.1 T than at 1.0 or 1.5 T. High-field-related advanced techniques, such as functional imaging, spectroscopy and microscopy, may become clinically useful in the near future. As long as there is an unlimited demand for MR examinations, it appears financially profitable to run a high-field system, despite the associated higher costs. However, if demand for MR becomes saturated, low-field systems will cause less financial strain on the reimbursement organisation and service provider. Recent emphasis on cost containment, the development of interventional techniques, the increased use of MR for patients in intensive care and operating suites, the deployment of magnets in office suites, and the development of new magnet configurations, all favour the supplementary use of low-field systems. Hence, MR units of all field strengths have a role in radiology.

CT and MRI were used in a prospective study of the central nervous system (CNS) manifestations in 41 consecutive children with neurofibromatosis type 1 (NF-1). Gadolinium-DTPA was used in 15 patients. MRI was more effective than CT in delimiting the extension of the optic pathway glioma and in evaluating associated cerebral malformations. MRI visualized lesions generally undetected by CT, in the form of iso- or hyperintense foci with respect to the cerebral cortex in T2-weighted sequences. Well-delimited lesions of high signal intensity were observed in the globus pallidus (22 cases), the internal capsule (6 cases), corpus callosum (2 cases), anterior commissure (1 case) and semioval center (2 cases). Poorly defined hyper- or isointense areas were also observed affecting the cerebellar white matter (21 cases) and brain stem (17 cases). None of these lesions showed Gadolinium-DTPA enhancement, and were of no clinical significance. MRI has displaced CT in the initial diagnosis of patients with NF-1. Periodic annual MRI controls are only justified in patients with MRI changes to evaluate the progression or stabilization of the lesions.