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Aim: The aim of this in vitro study was to perform a comparative evaluation of the length of resin tags produced by three different types of pit and fissure sealants (Embrace WetBond, Helioseal Clear, and Fuji VII) using scanning electron microscopy. Materials and Methods: Thirty extracted mandibular premolars were randomly divided into three groups of ten. Each group was treated with one of the sealants – Embrace WetBond, Helioseal Clear, or Fuji VII. Following cleaning and preparation, the sealants were applied according to the manufacturer’s instructions. Teeth were then sectioned and prepared for SEM investigation, and the length of resin tags was measured. Results: Scanning electron microscopy revealed Embrace WetBond produced significantly longer resin tags than Helioseal Clear and Fuji VII. Conclusion: The study concludes that Embrace WetBond sealant exhibited the longest resin tags, which may suggest a stronger mechanical bond to enamel.

The aim of this study is to explore the potential of CASCABELA thevetia (CT) bast fibers as reinforcement in polymer composites. For this purpose, the extracted fibers were chemically treated with various chemicals such as sodium hydroxide, potassium permanganate, sodium chlorite, and benzoyl chloride. After surface modifications, its physical and mechanical properties, chemical composition, and structure were studied. The X-ray diffraction (XRD) results revealed an increase in crystallinity index of the fibers as compared to untreated fibers with benzoyl chloride treated fibers showing the optimum result which agrees with the results obtained in the mechanical tests. Composites were fabricated by taking various wt.% of benzoyl chloride treated CT fibers in an epoxy matrix (i.e. 5, 10, 15, 20, 25, and 30 wt%) and their mechanical and wettability tests were carried out. It was observed that composites with 20 wt% of fiber loading show the highest mechanical properties (52.79 MPa tensile strength, 2.45 GPa Young’s modulus, 71.72 MPa flexural strength). All the fabricated composites showed contact angle less than 90°, which is associated with composite hydrophilic surface properties. These composites can be utilized in lightweight structural material and in automobile industries owing to its better properties.

This paper highlights the chemical surface modifications of Calotropis gigantea (CG) bast fiber for attaining suitable properties as reinforcements in polymeric composites. The effect of chemical modification on its various properties like physical, mechanical, thermal and morphological properties was also discussed in this research. For this purpose the extracted fibers were chemically treated with various chemicals such as sodium hydroxide, potassium permanganate, sodium chlorite and benzoyl chloride. After surface modifications, its density, mechanical property, thermal gravimetry analysis (TGA), Fourier transform infrared spectroscopy (FTIR) and surface morphology were thoroughly investigated. The tensile strength and Young’s modulus of alkali treated CG fiber was found to be 210.39 MPa and 1.77 GPa respectively. The crystallinity index was improved by 25.37% as compared with untreated CG fiber. Finally, it was observed that alkali treated fiber gives better performance and enhances various properties of Calotropis gigantea stem fibers for use as novel reinforcement in composite materials.

The goal of this study is to thoroughly comprehend the advantages of rattan (Calamus beccarii) as potential reinforcement in polymeric composites. The influence of various chemical treatments on thermal, morphological, mechanical and water absorption characteristics of natural rattan (RA) stem fiber were investigated. In this research, RA fiber surface was modified through different chemical treatments such as alkalization, bleaching, and benzoylation. The presence of voids and rough surfaces was investigated on SEM micrographs which are due to removal of lignin, wax, and oils from the fiber surface to a large extent. The results obtained from Fourier transform infrared may indicate the presence of cellulose, hemicellulose, and lignin compounds in the case of untreated and treated RA fiber. The increase in tensile strength and Young’s modulus confirms improvement in the mechanical properties of the RA fiber after chemical treatment. It was observed that alkali-treated RA fibers exhibit highest mechanical properties (295.28 MPa tensile strength, 8.23 GPa Young’s modulus). Also, X-ray diffraction analysis gives a higher crystallinity index (62.50%) for treated RA fiber. Thermogravimetric analysis confirms that there was an increase in the thermal stability of the fiber after chemical treatment. Overall results confirm that the RA fiber is appropriate for use as a reinforcing phase in composite materials for prospective engineering semi-structural applications such as roofing sheets, bricks, door panels, furniture panels, interior paneling, storage tanks, and pipelines.

Bauhinia vahlii (BV) is a great source of cellulosic biomass, and it is gaining popularity as a renewable resource. BV bast fiber is proposed to have the potential to replace synthetic fibers in biopolymer composites as a reinforcing material. This investigation deals with the extraction, surface modification and comprehensive characterization of BV bast fibers which could be used for the production of sustainable fiber-reinforced polymer composites. The extracted fibers were chemically treated with sodium hydroxide, sodium chlorite, and benzoyl chloride. Then, the chemical properties, mechanical properties, surface morphology and thermal properties were investigated. An improvement in chemical and mechanical properties was observed after surface modification of fibers. Benzoylation treated BV bast fibers revealed highest tensile strength of 128.56 MPa and Young’s modulus of 8.34 GPa. In addition, after treatment, the fibers had rougher surface as seen from SEM images. The surface treatments removed a specific quantity of hemicelluloses, lignin, and pectin from the natural fiber surface, according to FTIR analysis. The surface treatments had a good impact on the crystallinity index of the natural fibers, according to XRD analysis. The characterization results confirmed that BV bast fibers could be used for the production of sustainable fiber reinforced polymer composites.

The synbiotic combination of L. rhamnosus NCDC 298 and fructo-oligosaccharide (FOS) is known to be effective against diarrhoea by preventing the adhesion of pathogens to the gutt, hereby, preventing infection and pathology. Such synergistic effect of the combination has emerged as a favourable alternative to antibiotic use against diseases and growth promoters in the livestock industry. The present study assessed the health and growth performance of the calves supplemented fermentable synbiotic fortified milk from 4 to 90 days and observed its performance till 120th day of age. Body temperature and passive immunity (IgG) were significantly better in calves fed synbiotics with notable increase in body weight and heart girth post synbiotic feeding period. These calves had increased dry matter intake per animal/day when compared to the control animals. The populations of Lactobacillus sp. elevated with decreased pathogenic bacteria (Coliform) in faeces on feeding synbiotics and it continued even after 90 days of age indicating colonization of beneficial bacteria. Therefore, feeding of fermentable synbiotics had observable beneficial effects on health, immunity and growth of the Jersey crossbred calves. The findings encourage further verification of fermentable synbiotics fortified milk as a potential growth promoter to young dairy calves.

Introduction: Mild traumatic brain injury brain injury (mTBI) has traditionally been considered to cause no significant brain damage since symptoms spontaneously remit after a few days. However, this idea is facing increasing scrutiny. The purpose of this study is to demonstrate the presence of early cognitive alterations in a series of patients with mTBI and to link these findings to different markers of brain damage. Methods: We conducted a prospective study of a consecutive series of patients with mTBI who were evaluated over a 12-month period. Forty-one (3.7%) of the 1144 included patients had experienced a concussion. Patients underwent a routine clinical evaluation and a brain computed tomography (CT) scan and were also administered a standardised test for post-concussion symptoms within the first 24 h of mTBI and also 1-2 weeks later. The second assessment also included a neuropsychological test battery. The results of these studies were compared to those of a control group of 28 healthy volunteers with similar characteristics. Twenty patients underwent a magnetic resonance imaging (MRI) scan. Results: Verbal memory and learning were the cognitive functions most affected by mTBI. Seven out of the 20 patients with normal CT findings displayed structural alterations on MR images, which were compatible with diffuse axonal injury in two cases. Conclusions: Results from this pilot study suggest that early cognitive alterations and structural brain lesions affect a considerable percentage of patients with post-concussion syndrome following mTBI. Resumen: Introducción: Los traumatismos craneoencefálicos leves (TCE-L) han sido tradicionalmente considerados acontecimientos sin repercusiones cerebrales significativas, cuya sintomatología remite espontáneamente en unos días. Sin embargo, estos hechos son cada vez más cuestionados. Este estudio pretende objetivar la existencia de alteraciones cognitivas precoces en una serie de pacientes con TCE-L y relacionar los hallazgos con distintos marcadores de lesión cerebral. Métodos: Estudio prospectivo de una cohorte de pacientes con un TCE-L valorados de forma consecutiva durante 12 meses. De un total de 1.144 pacientes, se seleccionó a 41 (3,7%) que habían presentado una conmoción cerebral. Además de la valoración clínica habitual y de la práctica de una tomografía computarizada (TC) cerebral, los pacientes fueron estudiados mediante un test estandarizado para síntomas posconmocionales en las primeras 24 h después del TCE-L y al cabo de 1-2 semanas y, coincidiendo con la segunda valoración, mediante una batería neuropsicológica. Los resultados se compararon con los de un grupo de 28 voluntarios sanos de características parecidas. En 20 pacientes se practicó una resonancia magnética (RM) craneal. Resultados: En este análisis exploratorio, la memoria y el aprendizaje verbal fueron las funciones cognitivas más afectadas después del TCE-L. Siete de los 20 pacientes con TC cerebral normal presentaron alteraciones estructurales visibles por RM, que en dos casos fueron compatibles con la presencia de lesión axonal difusa. Conclusiones: Los resultados de este estudio piloto sugieren la presencia de alteraciones cognitivas precoces y lesiones cerebrales estructurales en un porcentaje no despreciable de pacientes que han presentado una conmoción cerebral recuperada después de un TCE-L. Keywords: Mild traumatic brain injury, Neuropsychological alterations, Diffuse axonal injury, Sport Concussion Assessment Tool 2, Susceptibility-weighted imaging, Post-concussion syndrome, Palabras clave: Traumatismo craneoencefálico leve, Déficits neuropsicológicos, Lesión axonal difusa, Sport Concussion Assessment Tool 2, Susceptibility weighted imaging, Síndrome posconmocional

Resumen: Introducción: Los traumatismos craneoencefálicos leves (TCE-L) han sido tradicionalmente considerados acontecimientos sin repercusiones cerebrales significativas, cuya sintomatología remite espontáneamente en unos días. Sin embargo, estos hechos son cada vez más cuestionados. Este estudio pretende objetivar la existencia de alteraciones cognitivas precoces en una serie de pacientes con TCE-L y relacionar los hallazgos con distintos marcadores de lesión cerebral. Métodos: Estudio prospectivo de una cohorte de pacientes con un TCE-L valorados de forma consecutiva durante 12 meses. De un total de 1.144 pacientes, se seleccionó a 41 (3,7%) que habían presentado una conmoción cerebral. Además de la valoración clínica habitual y de la práctica de una tomografía computarizada (TC) cerebral, los pacientes fueron estudiados mediante un test estandarizado para síntomas posconmocionales en las primeras 24 h después del TCE-L y al cabo de 1-2 semanas y, coincidiendo con la segunda valoración, mediante una batería neuropsicológica. Los resultados se compararon con los de un grupo de 28 voluntarios sanos de características parecidas. En 20 pacientes se practicó una resonancia magnética (RM) craneal. Resultados: En este análisis exploratorio, la memoria y el aprendizaje verbal fueron las funciones cognitivas más afectadas después del TCE-L. Siete de los 20 pacientes con TC cerebral normal presentaron alteraciones estructurales visibles por RM, que en 2 casos fueron compatibles con la presencia de lesión axonal difusa. Conclusiones: Los resultados de este estudio piloto sugieren la presencia de alteraciones cognitivas precoces y lesiones cerebrales estructurales en un porcentaje no despreciable de pacientes que han presentado una conmoción cerebral recuperada después de un TCE-L. Abstract: Introduction: Mild traumatic brain injury (mTBI) has traditionally been considered to cause no significant brain damage since symptoms spontaneously remit after a few days. However, this idea is facing increasing scrutiny. The purpose of this study is to demonstrate the presence of early cognitive alterations in a series of patients with mTBI and to link these findings to different markers of brain damage. Methods: We conducted a prospective study of a consecutive series of patients with mTBI who were evaluated over a 12-month period. Forty-one (3.7%) of the 1144 included patients had experienced a concussion. Patients underwent a routine clinical evaluation and a brain computed tomography (CT) scan, and were also administered a standardised test for post-concussion symptoms within the first 24 hours of mTBI and also 1 to 2 weeks later. The second assessment also included a neuropsychological test battery. The results of these studies were compared to those of a control group of 28 healthy volunteers with similar characteristics. Twenty patients underwent an MRI scan. Results: Verbal memory and learning were the cognitive functions most affected by mTBI. Seven out of the 20 patients with normal CT findings displayed structural alterations on MR images, which were compatible with diffuse axonal injury in 2 cases. Conclusions: Results from this pilot study suggest that early cognitive alterations and structural brain lesions affect a considerable percentage of patients with post-concussion syndrome following mTBI. Palabras clave: Traumatismo craneoencefálico leve, Déficits neuropsicológicos, Lesión axonal difusa, Sport Concussion Assessment Tool 2, Susceptibility weighted imaging, Síndrome posconmocional, Keywords: Mild traumatic brain injury, Neuropsychological alterations, Diffuse axonal injury, Sport Concussion Assessment Tool 2, Susceptibility-weighted imaging, Post-concussion syndrome

Resumen: Introducción: La malformación de Chiari tipo I (MC-I) se caracteriza por la existencia de una ectopia de las amígdalas del cerebelo que se sitúan por debajo del foramen mágnum, lo que puede asociarse a fenómenos compresivos del tronco del encéfalo, de la médula espinal alta y de los pares craneales. Las manifestaciones clínicas más frecuentes suelen ser las cefaleas occípito-nucales y los mareos, aunque el cortejo sintomático puede ser muy extenso. Sin embargo, un aspecto menos conocido es la repercusión de la malformación sobre las alteraciones respiratorias nocturnas y los trastornos del sueño. Fuentes: MEDLINE e información de pacientes con MC-I valorados en los servicios de neurocirugía y neurofisiología del Hospital Universitario Vall d’Hebron. Desarrollo: Artículo de revisión realizado a partir del análisis de todos los estudios publicados en MEDLINE a partir del año 1966, localizados a través del motor de búsqueda PubMed, utilizando combinaciones de las palabras clave: «Chiari malformation» o «Arnold-Chiari malformation» y «sleep apnea» o «sleep disorders». Conclusiones: Los pacientes con una MC-I presentan una mayor prevalencia de trastornos del sueño que la población general. En algunos estudios el 50% de los pacientes con MC-I presentan un síndrome de apnea-hipopnea del sueño (SAHS), habiéndose descrito incluso casos de muerte súbita probablemente relacionados con estos fenómenos. Estos resultados recomiendan incluir el análisis de los parámetros respiratorios nocturnos en el estudio de los pacientes con MC-I. Identificar la presencia de un SAHS contribuye a optimizar el tratamiento de estos pacientes, mejorando la calidad de vida y su pronóstico. Abstract: Introduction: Chiari type I malformation (CM-I) is characterised by caudal ectopia of the cerebellar tonsils through the foramen magnum. This is associated with brain stem, high spinal cord, and cranial nerve compression phenomena. The most frequent symptoms are occipital headaches and dizziness. Less well-known symptoms are sleep disorders and nocturnal respiratory abnormalities. Sources: MEDLINE and information from patients evaluated at the Neurosurgery and Clinical Neurophysiology Departments at Hospital Universitario Vall d’Hebron. Development: Review article based on data obtained from MEDLINE articles since 1966, using combinations of the following keywords: «Chiari malformation» or «Arnold-Chiari malformation» and «sleep apnea» or «sleep disorders». Conclusions: CM-I patients show a higher prevalence of sleep disorders than that observed in the general population. Some studies report a 50% prevalence of sleep apnea-hypopnea syndrome (SAHS), probably associated with sudden death in some cases. These results support analysing sleep respiratory parameters in theses patients. Identifying SAHS symptoms may help optimise treatment, thereby improving quality of life and prognosis. Palabras clave: Malformación de Chiari, Malformación de Chiari tipo I, Malformación de Arnold-Chiari, Alteraciones del sueño, Apneas, Hipopneas, Síndrome de apnea del sueño, Keywords: Chiari malformation, Chiari malformation type I, Arnold-Chiari malformation, Sleep disorders, Apnea, Hypopnea, Sleep apnea syndrome

Introduction: Chiari type I malformation (CM-I) is characterised by caudal ectopia of the cerebellar tonsils through the foramen magnum. This is associated with brain stem, high spinal cord, and cranial nerve compression phenomena. The most frequent symptoms are occipital headaches and dizziness. Less well-known symptoms are sleep disorders and nocturnal respiratory abnormalities. Sources: MEDLINE and information from patients evaluated at the Neurosurgery and Clinical Neurophysiology Departments at Hospital Universitario Vall d’Hebron. Development: Review article based on data obtained from MEDLINE articles since 1966, using combinations of the following keywords: “Chiari malformation” or “Arnold-Chiari malformation” and “sleep apnea” or “sleep disorders”. Conclusions: CM-I patients show a higher prevalence of sleep disorders than that observed in the general population. Some studies report a 50% prevalence of sleep apnea-hypopnea syndrome (SAHS), probably associated with sudden death in some cases. These results support analysing sleep respiratory parameters in these patients. Identifying SAHS symptoms may help optimise treatment, thereby improving quality of life and prognosis. Resumen: Introducción: La malformación de Chiari tipo I (MC-I) se caracteriza por la existencia de una ectopia de las amígdalas del cerebelo que se sitúan por debajo del foramen mágnum, lo que puede asociarse a fenómenos compresivos del tronco del encéfalo, de la médula espinal alta y de los pares craneales. Las manifestaciones clínicas más frecuentes suelen ser las cefaleas occípitonucales y los mareos, aunque el cortejo sintomático puede ser muy extenso. Sin embargo, un aspecto menos conocido es la repercusión de la malformación sobre las alteraciones respiratorias nocturnas y los trastornos del sueño. Fuentes: MEDLINE e información de pacientes con MC-I valorados en los servicios de neurocirugía y neurofisiología del Hospital Universitario Vall d’Hebron. Desarrollo: Artículo de revisión realizado a partir del análisis de todos los estudios publicados en MEDLINE a partir del año 1966, localizados a través del motor de búsqueda PubMed, utilizando combinaciones de las palabras clave: «Chiari malformation» o «Arnold-Chiari malformation» y «sleep apnea» o «sleep disorders». Conclusiones: Los pacientes con una MC-I presentan una mayor prevalencia de trastornos del sueño que la población general. En algunos estudios el 50% de los pacientes con MC-I presentan un síndrome de apnea-hipopnea del sueño (SAHS), habiéndose descrito incluso casos de muerte súbita probablemente relacionados con estos fenómenos. Estos resultados recomiendan incluir el análisis de los parámetros respiratorios nocturnos en el estudio de los pacientes con MC-I. Identificar la presencia de un SAHS contribuye a optimizar el tratamiento de estos pacientes, mejorando la calidad de vida y su pronóstico. Keywords: Chiari malformation, Chiari malformation type I, Arnold-Chiari malformation, Sleep disorders, Apnea, Hypopnea, Sleep apnea syndrome, Palabras clave: Malformación de Chiari, Malformación de Chiari tipo I, Malformación de Arnold-Chiari, Alteraciones del sueño, Apneas, Hipopneas, Síndrome de apnea del sueño

Resumen: Introducción: La exploración de las pupilas constituye una parte fundamental de la exploración neurológica. El tamaño y la reactividad a la luz de ambas pupilas deben registrarse de forma individual y periódica, dado que una alteración en estos parámetros puede constituir el único signo detectable de deterioro neurológico en determinados pacientes. Sin embargo, existe una gran variabilidad intra-observadores e inter-observadores al analizar estos parámetros, debido a la influencia de una serie de factores tales como la variabilidad en la luz ambiental, la agudeza visual y experiencia del propio observador, intensidad del estímulo luminoso y el método utilizado para dirigir este estímulo.En los últimos años las cámaras digitales han incorporado dispositivos de infrarrojos que han permitido desarrollar equipos digitales portátiles y de fácil manejo, que permiten realizar estudios repetidos y no invasivos del tamaño y reactividad pupilar a la luz con un método objetivo, accesible y económico. Desarrollo: El objetivo de esta revisión es describir los fundamentos de la pupilometría por infrarrojos y discutir sus posibles aplicaciones en la monitorización del paciente neurocrítico. En esta revisión también se incluyen una serie de recomendaciones metodológicas a considerar en la exploración de las pupilas. Conclusiones: La posibilidad de evaluar los cambios en la reactividad pupilar de forma precoz, objetiva y quasi-continua aporta un nuevo método de monitorización no invasivo que podría mejorar el factor predictivo del deterioro neurológico y monitorizar el estado neurológico a la cabecera del paciente, evitando así exámenes innecesarios y permitiendo intervenciones terapéuticas precoces. Abstract: Introduction: Pupil assessment is a fundamental part of the neurological examination. Size and reactivity to light of each pupil should be recorded periodically since changes in these parameters may represent the only detectable sign of neurological deterioration in some patients. However, there is great intraobserver and interobserver variability in pupil examination due to the influence of many factors, such as the difference in ambient lighting, the visual acuity and experience of the examiner, the intensity of the luminous stimulus, and the method used to direct this stimulus.In recent years, digital cameras have incorporated infrared devices allowing the development of user-friendly portable devices that permit repeated, non-invasive examinations of pupil size and its reactivity to light with an objective, accessible and inexpensive method. Development: The purpose of this review is to describe the fundamentals of infrared pupillometry and discuss potential applications in the monitoring of neurocritical patients. We also present some recommendations in the routine assessment of pupils in neurocritical patients. Conclusions: The possibility of evaluating the changes in pupil reactivity in an early, objective and almost continuous way provides a new non-invasive monitoring method. This method could improve the predictive factor of neurological deterioration and the bedside monitoring of the neurological state of the patient, avoiding unnecessary examinations and enabling early therapeutic intervention. Palabras clave: Neuromonitorización, Neuroworsening, Pupilas, Pupilometría infrarroja, Pupilómetro, Valoración pupilar, Keywords: Infrared pupillometry, Neuro-monitoring, Neuro-deterioration, Pupillometer, Pupil assessment, Pupils

Introduction: Pupil assessment is a fundamental part of the neurological examination. Size and reactivity to light of each pupil should be recorded periodically since changes in these parameters may represent the only detectable sign of neurological deterioration in some patients. However, there is great intraobserver and interobserver variability in pupil examination due to the influence of many factors, such as the difference in ambient lighting, the visual acuity and experience of the examiner, the intensity of the luminous stimulus, and the method used to direct this stimulus.In recent years, digital cameras have incorporated infrared devices allowing the development of user-friendly portable devices that permit repeated, non-invasive examinations of pupil size and its reactivity to light with an objective, accessible and inexpensive method. Development: The purpose of this review is to describe the fundamentals of infrared pupillometry and discuss potential applications in the monitoring of neurocritical patients. We also present some recommendations in the routine assessment of pupils in neurocritical patients. Conclusions: The possibility of evaluating the changes in pupil reactivity in an early, objective and almost continuous way provides a new non-invasive monitoring method. This method could improve the predictive factor of neurological deterioration and the bedside monitoring of the neurological state of the patient, avoiding unnecessary examinations and enabling early therapeutic intervention. Resumen: Introducción: La exploración de las pupilas constituye una parte fundamental de la exploración neurológica. El tamaño y la reactividad a la luz de ambas pupilas deben registrarse de forma individual y periódica, dado que una alteración en estos parámetros puede constituir el único signo detectable de deterioro neurológico en determinados pacientes. Sin embargo, existe una gran variabilidad intra-observadores e inter-observadores al analizar estos parámetros, debido a la influencia de una serie de factores tales como la variabilidad en la luz ambiental, la agudeza visual y experiencia del propio observador, intensidad del estímulo luminoso y el método utilizado para dirigir este estímulo.En los últimos años las cámaras digitales han incorporado dispositivos de infrarrojos que han permitido desarrollar equipos digitales portátiles y de fácil manejo, que permiten realizar estudios repetidos y no invasivos del tamaño y reactividad pupilar a la luz con un método objetivo, accesible y económico. Desarrollo: El objetivo de esta revisión es describir los fundamentos de la pupilometría por infrarrojos y discutir sus posibles aplicaciones en la monitorización del paciente neurocrítico. En esta revisión también se incluyen una serie de recomendaciones metodológicas a considerar en la exploración de las pupilas. Conclusiones: La posibilidad de evaluar los cambios en la reactividad pupilar de forma precoz, objetiva y quasi-continua aporta un nuevo método de monitorización no invasivo que podría mejorar el factor predictivo del deterioro neurológico y monitorizar el estado neurológico a la cabecera del paciente, evitando así exámenes innecesarios y permitiendo intervenciones terapéuticas precoces. Keywords: Infrared pupillometry, Neuro-monitoring, Neuro-deterioration, Pupillometer, Pupil assessment, Pupils, Palabras clave: Neuromonitorización, Neuroworsening, Pupilas, Pupilometría infrarroja, Pupilómetro, Valoración pupilar

Resumen: Objetivos: Determinar la respuesta a los potenciales evocados visuales (P300) en pacientes con hidrocefalia de presión normal (NPH) antes y después de la implantación de una derivación de líquido cefalorraquídeo (LCR) y establecer su relación con la situación clínica y cognitiva antes y después del tratamiento quirúrgico. Métodos: Estudio prospectivo en una serie de 26 pacientes con NPH a los que se realizó una valoración clínica y neuropsicológica y se analizó la P300 antes y 6 meses después del tratamiento quirúrgico. Los resultados de la P300 de los pacientes antes y después del tratamiento se compararon con los de un grupo control de 18 voluntarios sanos. Resultados: Once de los pacientes con una NPH (42,3%) presentaron onda P300 antes del tratamiento quirúrgico, mientras que esta onda estaba presente en los 18 individuos del grupo control (100%). La latencia de la onda fue significativamente superior en los pacientes que en el grupo control. Seis meses después de la implantación de la derivación de LCR, 20 (76,9%) de los pacientes con NPH presentaron la onda P300, sin que hubiera diferencias significativas en las latencias de la onda entre ambos grupos. No hubo diferencias en los estudios neuropsicológicos y en el grado de independencia en la realización de las actividades de la vida diaria entre los pacientes que presentaron la P300 antes de la cirugía y los que no la presentaron, ni entre los cambios de la P300 y los cambios clínicos o cognitivos después del tratamiento quirúrgico. Conclusiones: Un porcentaje importante de pacientes con una NPH no presentan onda P300 o su latencia está incrementada. Estas alteraciones pueden revertirse en muchos pacientes al implantar una derivación de LCR Abstract: Objective: To determine the response to cognitive event-related potentials (P300) in patients with normal-pressure hydrocephalus (NPH) and their relationship with clinical and cognitive status before and after shunt surgery. Methods: We performed a prospective study in a series of 26 patients with NPH who underwent clinical and cognitive assessment before surgery and 6 months afterwards. Visual P300 potentials obtained before and after treatment were also compared with those obtained in 18 healthy volunteers. Results: Before shunting, the P300 wave was detected in 11 (42.3%) NPH patients, compared with the 18 (100%) volunteers. Six months after shunting, the P300 wave was found in 20 (76.9%) NPH patients. P300 latency was significantly longer in NPH patients than in the control group before surgery, but not at 6 months after surgery. No significant differences in neuropsychological studies or in the level of dependence for daily life activities were found between the subgroups of NPH patients with and without pre-surgical P300 waves, or between changes in P300 parameters and clinical and cognitive changes. Conclusions: The P300 wave was delayed or undetectable in a substantial percentage of patients with NPH before surgery. These alterations can be reversed by shunting. P300 analysis and neuropsychological tests could be complementary measures to evaluate functional status in patients with NPH. Palabras clave: Hidrocefalia de presión normal, Neuropsicología, Potenciales evocados cognitivos, Potenciales evocados visuales, P300, Keywords: Normal pressure hydrocephalus, Neuropsychology, Cognitive event-related brain potentials, Visual event-related potentials, P300

Objective: To determine the response to cognitive event-related potentials (P300) in patients with normal-pressure hydrocephalus (NPH) and their relationship with clinical and cognitive status before and after shunt surgery. Methods: We performed a prospective study in a series of 26 patients with NPH who underwent clinical and cognitive assessment before surgery and 6 months afterwards. Visual P300 potentials obtained before and after treatment were also compared with those obtained in 18 healthy volunteers. Results: Before shunting, the P300 wave was detected in 11 (42.3%) NPH patients, compared with the 18 (100%) volunteers. Six months after shunting, the P300 wave was found in 20 (76.9%) NPH patients. P300 latency was significantly longer in NPH patients than in the control group before surgery, but not at 6 months after surgery. No significant differences in neuropsychological studies or in the level of dependence for daily life activities were found between the subgroups of NPH patients with and without presurgical P300 waves, or between changes in P300 parameters and clinical and cognitive changes. Conclusions: The P300 wave was delayed or undetectable in a substantial percentage of patients with NPH before surgery. These alterations can be reversed by shunting. P300 analysis and neuropsychological tests could be complementary measures to evaluate functional status in patients with NPH. Resumen: Objetivos: Determinar la respuesta a los potenciales evocados visuales (P300) en pacientes con hidrocefalia de presión normal (NPH) antes y después de la implantación de una derivación de líquido cefalorraquídeo (LCR) y establecer su relación con la situación clínica y cognitiva antes y después del tratamiento quirúrgico. Métodos: Estudio prospectivo en una serie de 26 pacientes con NPH a los que se realizó una valoración clínica y neuropsicológica y se analizó la P300 antes y 6 meses después del tratamiento quirúrgico. Los resultados de la P300 de los pacientes antes y después del tratamiento se compararon con los de un grupo control de 18 voluntarios sanos. Resultados: Once de los pacientes con una NPH (42,3%) presentaron onda P300 antes del tratamiento quirúrgico, mientras que esta onda estaba presente en los 18 individuos del grupo control (100%). La latencia de la onda fue significativamente superior en los pacientes que en el grupo control. Seis meses después de la implantación de la derivación de LCR, 20 (76,9%) de los pacientes con NPH presentaron la onda P300, sin que hubiera diferencias significativas en las latencias de la onda entre ambos grupos. No hubo diferencias en los estudios neuropsicológicos y en el grado de independencia en la realización de las actividades de la vida diaria entre los pacientes que presentaron la P300 antes de la cirugía y los que no la presentaron, ni entre los cambios de la P300 y los cambios clínicos o cognitivos después del tratamiento quirúrgico. Conclusiones: Un porcentaje importante de pacientes con una NPH no presentan onda P300 o su latencia está incrementada. Estas alteraciones pueden revertirse en muchos pacientes al implantar una derivación de LCR. Keywords: Normal pressure hydrocephalus, Neuropsychology, Cognitive event-related brain potentials, Visual event-related potentials, P300, Palabras clave: Hidrocefalia de presión normal, Neuropsicología, Potenciales evocados cognitivos, Potenciales evocados visuales, P300