Automated Segmentation of Cerebral Vasculature with Aneurysms in 3DRA and TOF-MRA using Geodesic Active Regions: an Evaluation Study

Purpose: To evaluate the suitability of an improved version of an automatic segmentation method based on geodesic active regions (GAR) for segmenting cerebral vasculature with aneurysms from 3D X-ray reconstruc-tion angiography (3DRA) and time of °ight magnetic resonance angiography (TOF-MRA) images available in the clinical routine.Methods: Three aspects of the GAR method have been improved: execution time, robustness to variability in imaging protocols and robustness to variability in image spatial resolutions. The improved GAR was retrospectively evaluated on images from patients containing intracranial aneurysms in the area of the Circle of Willis and imaged with two modalities: 3DRA and TOF-MRA. Images were obtained from two clinical centers, each using di®erent imaging equipment. Evaluation included qualitative and quantitative analyses ofthe segmentation results on 20 images from 10 patients. The gold standard was built from 660 cross-sections (33 per image) of vessels and aneurysms, manually measured by interventional neuroradiologists. GAR has also been compared to an interactive segmentation method: iso-intensity surface extraction (ISE). In addition, since patients had been imaged with the two modalities, we performed an inter-modality agreement analysis with respect to both the manual measurements and each of the two segmentation methods. Results: Both GAR and ISE di®ered from the gold standard within acceptable limits compared to the imaging resolution. GAR (ISE, respectively) had an average accuracy of 0.20 (0.24) mm for 3DRA and 0.27 (0.30) mm for TOF-MRA, and had a repeatability of 0.05 (0.20) mm. Compared to ISE, GAR had a lower qualitative error in the vessel region and a lower quantitative error in the aneurysm region. The repeatabilityof GAR was superior to manual measurements and ISE. The inter-modality agreement was similar between GAR and the manual measurements. Conclusions: The improved GAR method outperformed ISE qualitatively as well as quantitatively and is suitable for segmenting 3DRA and TOF-MRA images from clinical routine.

Deployment of self-expandable stents in aneurysmatic cerebral vessels: comparison of different computational approaches for interventional planning

In the last few years, there has been a growing focus on faster computational methods to support clinicians in planning stenting procedures. This study investigates the possibility of introducing computational approximations in modelling stent deployment in aneurysmatic cerebral vessels to achieve simulations compatible with the constraints of real clinical workflows. The release of a self-expandable stent in a simplified aneurysmatic vessel was modelled in four different initial positions. Six progressively simplified modelling approaches (based on Finite Element method and Fast Virtual Stenting – FVS) have been used. Comparing accuracy of the results, the final configuration of the stent is more affected by neglecting mechanical properties of materials (FVS) than by adopting 1D instead of 3D stent models. Nevertheless, the differencesshowed are acceptable compared to those achieved by considering different stent initial positions. Regarding computationalcosts, simulations involving 1D stent features are the only ones feasible in clinical context.

Morphodynamic analysis of cerebral aneurysm pulsation from time-resolved rotational angiography

This paper presents a technique to estimate and model patient-specific pulsatility of cerebral aneurysms over onecardiac cycle, using 3D rotational X-ray angiography (3DRA) acquisitions. Aneurysm pulsation is modeled as a time varying-spline tensor field representing the deformation applied to a reference volume image, thus producing the instantaneousmorphology at each time point in the cardiac cycle. The estimated deformation is obtained by matching multiple simulated projections of the deforming volume to their corresponding original projections. A weighting scheme is introduced to account for the relevance of each original projection for the selected time point. The wide coverage of the projections, together with the weighting scheme, ensures motion consistency in all directions. The technique has been tested on digital and physical phantoms that are realistic and clinically relevant in terms of geometry, pulsation and imaging conditions. Results from digital phantomexperiments demonstrate that the proposed technique is able to recover subvoxel pulsation with an error lower than 10% of the maximum pulsation in most cases. The experiments with the physical phantom allowed demonstrating the feasibility of pulsation estimation as well as identifying different pulsation regions under clinical conditions.

Detecció automàtica de punts facials característics mitjançant un algoritme inspirat en el còrtex cerebral

En aquest article presentem l'aplicació d'un algoritme inspirat en el còrtex cerebral anomenat HMAX com a part central d'un procés de detecció automàtica de punts facials característics en imatges.

Glibenclamide enhances neurogenesis and improves long-term functional recovery after transient focal cerebral ischemia

Glibenclamide is neuroprotective against cerebral ischemia in rats. We studied whether glibenclamide enhances long-term brain repair and improves behavioral recovery after stroke. Adult male Wistar rats were subjected to transient middle cerebral artery occlusion (MCAO) for 90 minutes. A low dose of glibenclamide (total 0.6mg) was administered intravenously 6, 12, and 24 hours after reperfusion. We assessed behavioral outcome during a 30-day follow-up and animals were perfused for histological evaluation. In vitro specific binding of glibenclamide to microglia increased after pro-inflammatory stimuli. In vivo glibenclamide was associated with increased migration of doublecortin-positive cells in the striatum toward the ischemic lesion 72 hours after MCAO, and reactive microglia expressed sulfonylurea receptor 1 (SUR1) and Kir6.2 in the medial striatum. One month after MCAO, glibenclamide was also associated with increased number of NeuN-positive and 5-bromo-2-deoxyuridine-positive neurons in the cortex and hippocampus, and enhanced angiogenesis in the hippocampus. Consequently, glibenclamide-treated MCAO rats showed improved performance in the limb-placing test on postoperative days 22 to 29, and in the cylinder and water-maze test on postoperative day 29. Therefore, acute blockade of SUR1 by glibenclamide enhanced long-term brain repair in MCAO rats, which was associated with improved behavioral outcome.

Evaluación económica de la determinación del propéptido natriurético cerebral N-terminal (NT-proBNP) en pacientes con disnea en los servicios de urgencias españoles

Introducción: Analizar la eficiencia de añadir la determinación NT-proBNP al examen clínico convencional (ECC) para el diagnóstico de insuficiencia cardíaca (IC) en pacientes con disnea que acuden a servicios de urgencias (SU) españoles. Material y métodos: Se desarrolló un árbol de decisión para evaluar los resultados clínicos y económicos de ambas alternativas durante 60 días de seguimiento desde la visita al SU en pacientes hospitalizados y no hospitalizados. Los parámetros clínicos fueron principalmente obtenidos del estudio PRIDE y validados por médicos de SU y cardiólogos. El punto de corte de la determinación NT-proBNP fue de 900 pg/mL (sensibilidad del 90% y especificidad del 85%). En base a datos espa noles publicados, se asumió que el 65% de pacientes con disnea sufrían IC. El uso de recursos fue identificado mediante opinión de expertos y evaluado desde la perspectiva del Sistema Nacional de Salud (SNS). El análisis comparó el diagnóstico final del paciente con el diagnóstico realizado en el SU. Se realizaron diversos análisis de sensibilidad para evaluar la incertidumbre del modelo. Resultados: El diagnóstico incorporando la determinación NT-proBNP fue correcto en el 91,96% de los pacientes (59,09% verdaderos positivos y 32,87% verdaderos negativos) frente al 85,53% mediante ECC (50,79% verdaderos positivos y 34,74% verdaderos negativos). La incorporación de la determinación NT-proBNP resultó tener un coste menor (3.720 versus 5.188 ). Los análisis de sensibilidad realizados confirmaron los resultados.

Cerebral infarction in diabetes: Clinical pattern, stroke subtypes,and predictors of in-hospital mortality

Background: To compare the characteristics and prognostic features of ischemic stroke in patients with diabetes and without diabetes, and to determine the independent predictors of in-hospital mortality in people with diabetes and ischemic stroke.Methods: Diabetes was diagnosed in 393 (21.3%) of 1,840 consecutive patients with cerebral infarction included in a prospective stroke registry over a 12-year period. Demographic characteristics, cardiovascular risk factors, clinical events, stroke subtypes, neuroimaging data, and outcome in ischemic stroke patients with and without diabetes were compared. Predictors of in-hospital mortality in diabetic patients with ischemic stroke were assessed by multivariate analysis. Results: People with diabetes compared to people without diabetes presented more frequently atherothrombotic stroke (41.2% vs 27%) and lacunar infarction (35.1% vs 23.9%) (P < 0.01). The in-hospital mortality in ischemic stroke patients with diabetes was 12.5% and 14.6% in those without (P = NS). Ischemic heart disease, hyperlipidemia, subacute onset, 85 years old or more, atherothrombotic and lacunar infarcts, and thalamic topography were independently associated with ischemic stroke in patients with diabetes, whereas predictors of in-hospital mortality included the patient's age, decreased consciousness, chronic nephropathy, congestive heart failure and atrial fibrillation. Conclusion: Ischemic stroke in people with diabetes showed a different clinical pattern from those without diabetes, with atherothrombotic stroke and lacunar infarcts being more frequent. Clinical factors indicative of the severity of ischemic stroke available at onset have a predominant influence upon in-hospital mortality and may help clinicians to assess prognosis more accurately.

Parálisis cerebral. Tratamiento ortopodológico

Después de varios años de experiencia en la aplicación de las férulas estabilizadoras del sistema aquileocalcáneo plantar FESAP) en pacientes con parálisis cerebral, creemos que deberían ser el tratamiento ortopodológico de elección del pie equino en niños con miopatías y lesiones neurológlcas de la unidad motora, del sistema piramidal o extrapiramidal, tanto por su perfecta adaptación a la morfología de la extremidad inferior como por sus caracteristicas funcionales y sus acciones fisio1ógicas y terapéuticas.

El paciente con parálisis cerebral y su tratamiento odontoestomatológico

En el presente trabajo, se explican las características generales y odontoestomatológicas así como los tratamientos necesarios de los pacientes afectos de parálisis cerebral

Memòria, reorganització cerebral evidenciada amb fMRI i hipocamp

Aquesta pretén ser una revisió general dels processos cognitius normals i de la capacitat de reorganització cerebral en cas de dany cerebral adquirit (lesions i malalties neurodegeneratives).

La inclusió dels alumnes amb paràlisi cerebral, una mirada des de la teràpia ocupacional

Aquest és un projecte d'investigació descriptiva. Té com a finalitat conèixer i comprendre com és la inclusió dels nens amb Paràlisis Cerebral a les escoles ordinàries (bressol, primària i secundària), de la ciutat de Barcelona, des de la mirada de la Teràpia Ocupacional. Per tant, primer s'ha d'investigar quants alumnes amb aquesta lesió estan inclosos en escoles ordinàries, com també conèixer quants alumnes tornen a l'escola especial després d'estar escolaritzats a la ordinària. D'altra banda, es pretén descriure les perspectives i percepcions dels professionals i els alumnes implicats a la inclusió, i què succeeix a l'escola ordinària perquè alguns alumnes hagin de tornar a l'especial en algun moment de la seva escolarització. El projecte és de caire qualitatiu, on els instruments per l'obtenció de dades són protocols d'observació, entrevistes semi- estructurades i enquestes. Encara que per obtenir la mostra i els participants s'utilitzaran tècniques quantitatives. Les limitacions de l'estudi seran aquelles escoles, professionals i alumnes que per motius personals no vulguin participar de la mostra.

La teràpia assistida amb gossos: una eina terapèutica en el tractament de la fisioteràpia en ens amb paràlisi cerebral espàstica

La Teràpia Assistida amb Animals (TAA) mostra antecedents des del segle XX utilitzant diversos animals amb finalitats terapèutiques, però en realitat, hi ha pocs estudis sobre els beneficis de la TAA. Si partim de que hi ha poca informació i recerca en la globalitat d‟aquest tipus de teràpia s‟ha de dir que la recerca clínica de La Teràpia Assistida amb Gossos en l‟àmbit de Rehabilitació Pediàtrica en Fisioteràpia és un món per descobrir. L‟estudi i investigació de “La Teràpia Assistida amb gossos: una eina terapèutica en el tractament de Fisioteràpia en nens amb Lesió Cerebral Espàstica” v ol mostrar de manera qualitativa els beneficis que pot duu a terme aquesta tipologia de treball mitjançant el gos com a eina motivadora en el tractament de Fisioteràpia. L‟estudi consta d‟un grup mostra de 4 nens amb Lesió Cerebral Espàstica que realitzaran un tractament amb Teràpia Assistida amb Gossos d‟un curs de durada, realitzant una sessió per setmana de manera individual on l‟objectiu serà treballar la Rehabilitació Física mitjançant diverses tipologies d‟exercicis enfocades a millorar el control cefàlic, fomentar el control del to muscular , afavorir la bipedestació i/o marxa i estimular la motricitat fina. El recull es farà qualitativament mitjançant diari de camp i visionats d‟imatges.

Glibenclamide enhances neurogenesis and improves long-term functional recovery after transient focal cerebral ischemia

Glibenclamide is neuroprotective against cerebral ischemia in rats. We studied whether glibenclamide enhances long-term brain repair and improves behavioral recovery after stroke. Adult male Wistar rats were subjected to transient middle cerebral artery occlusion (MCAO) for 90 minutes. A low dose of glibenclamide (total 0.6mg) was administered intravenously 6, 12, and 24 hours after reperfusion. We assessed behavioral outcome during a 30-day follow-up and animals were perfused for histological evaluation. In vitro specific binding of glibenclamide to microglia increased after pro-inflammatory stimuli. In vivo glibenclamide was associated with increased migration of doublecortin-positive cells in the striatum toward the ischemic lesion 72 hours after MCAO, and reactive microglia expressed sulfonylurea receptor 1 (SUR1) and Kir6.2 in the medial striatum. One month after MCAO, glibenclamide was also associated with increased number of NeuN-positive and 5-bromo-2-deoxyuridine-positive neurons in the cortex and hippocampus, and enhanced angiogenesis in the hippocampus. Consequently, glibenclamide-treated MCAO rats showed improved performance in the limb-placing test on postoperative days 22 to 29, and in the cylinder and water-maze test on postoperative day 29. Therefore, acute blockade of SUR1 by glibenclamide enhanced long-term brain repair in MCAO rats, which was associated with improved behavioral outcome.

Structural changes induced by daily music listening in the recovering brain after middle cerebral artery stroke: a voxel-based morphometry study

Music is a highly complex and versatile stimulus for the brain that engages many temporal, frontal, parietal, cerebellar, and subcortical areas involved in auditory, cognitive, emotional, and motor processing. Regular musical activities have been shown to effectively enhance the structure and function of many brain areas, making music a potential tool also in neurological rehabilitation. In our previous randomized controlled study, we found that listening to music on a daily basis can improve cognitive recovery and improve mood after an acute middle cerebral artery stroke. Extending this study, a voxel-based morphometry (VBM) analysis utilizing cost function masking was performed on the acute and 6-month post-stroke stage structural magnetic resonance imaging data of the patients (n = 49) who either listened to their favorite music [music group (MG), n = 16] or verbal material [audio book group (ABG), n = 18] or did not receive any listening material [control group (CG), n = 15] during the 6-month recovery period. Although all groups showed significant gray matter volume (GMV) increases from the acute to the 6-month stage, there was a specific network of frontal areas [left and right superior frontal gyrus (SFG), right medial SFG] and limbic areas [left ventral/subgenual anterior cingulate cortex (SACC) and right ventral striatum (VS)] in patients with left hemisphere damage in which the GMV increases were larger in the MG than in the ABG and in the CG. Moreover, the GM reorganization in the frontal areas correlated with enhanced recovery of verbal memory, focused attention, and language skills, whereas the GM reorganization in the SACC correlated with reduced negative mood. This study adds on previous results, showing that music listening after stroke not only enhances behavioral recovery, but also induces fine-grained neuroanatomical changes in the recovering brain.

Evaluación económica de la determinación del propéptido natriurético cerebral N-terminal (NT-proBNP) en pacientes con disnea en los servicios de urgencias españoles

Introducción: Analizar la eficiencia de añadir la determinación NT-proBNP al examen clínico convencional (ECC) para el diagnóstico de insuficiencia cardíaca (IC) en pacientes con disnea que acuden a servicios de urgencias (SU) españoles. Material y métodos: Se desarrolló un árbol de decisión para evaluar los resultados clínicos y económicos de ambas alternativas durante 60 días de seguimiento desde la visita al SU en pacientes hospitalizados y no hospitalizados. Los parámetros clínicos fueron principalmente obtenidos del estudio PRIDE y validados por médicos de SU y cardiólogos. El punto de corte de la determinación NT-proBNP fue de 900 pg/mL (sensibilidad del 90% y especificidad del 85%). En base a datos espa noles publicados, se asumió que el 65% de pacientes con disnea sufrían IC. El uso de recursos fue identificado mediante opinión de expertos y evaluado desde la perspectiva del Sistema Nacional de Salud (SNS). El análisis comparó el diagnóstico final del paciente con el diagnóstico realizado en el SU. Se realizaron diversos análisis de sensibilidad para evaluar la incertidumbre del modelo. Resultados: El diagnóstico incorporando la determinación NT-proBNP fue correcto en el 91,96% de los pacientes (59,09% verdaderos positivos y 32,87% verdaderos negativos) frente al 85,53% mediante ECC (50,79% verdaderos positivos y 34,74% verdaderos negativos). La incorporación de la determinación NT-proBNP resultó tener un coste menor (3.720 versus 5.188 ). Los análisis de sensibilidad realizados confirmaron los resultados.