Influence of glioblastoma contact with the subventricular zone on survival and recurrence patterns

Background There is growing evidence that the subventricular zone (SVZ) may be involved in both the initiation and progression of glioblastoma (GB). We aimed to assess tumor proximity to the SVZ as a potential prognostic factor in GB. Method Retrospective study of 133 patients diagnosed with primary GB who underwent surgery followed by temozolomide-based chemoradiation between 2010 and 2016. All lesions were classified according to their anatomic relation with the SVZ. We determined the effect of tumor contact with the SVZ on progression-free survival (PFS), overall survival (OS), type, and patterns of recurrence. Results At a median follow-up of 18.6 months (95% CI 15.9–21.2), PFS and OS were 7.5 (95% CI 6.7–8.3) and 13.9 (95% CI 10.9–16.9) months, respectively. On the univariate analyses, initial contact with the SVZ was a factor for poor prognosis for both PFS (6.1 vs. 8.7 months; p = 0.006) and OS (10.6 vs. 17.9 months; p = 0.037). On the multivariate analysis, tumor contact with the SVZ remained statistically significant for PFS, but not OS. Patients with SVZ-contacting tumors presented a higher rate of aggressive clinical progression (30.9% vs. 11.3%; p = 0.007) and contralateral relapse patterns (23.4% vs. 9.1%; p = 0.048). Conclusions Our results suggest that glioblastoma contact with the SVZ appears to be an independent prognostic factor for poor PFS. The presence of an SVZ-contacting tumor was associated with more aggressive recurrences and a higher rate of contralateral relapses. These findings suggest that this variable may be a new prognostic factor in glioblastoma (AU)

Influence of glioblastoma contact with the subventricular zone on survival and recurrence patterns.

BACKGROUND: There is growing evidence that the subventricular zone (SVZ) may be involved in both the initiation and progression of glioblastoma (GB). We aimed to assess tumor proximity to the SVZ as a potential prognostic factor in GB. METHOD: Retrospective study of 133 patients diagnosed with primary GB who underwent surgery followed by temozolomide-based chemoradiation between 2010 and 2016. All lesions were classified according to their anatomic relation with the SVZ. We determined the effect of tumor contact with the SVZ on progression-free survival (PFS), overall survival (OS), type, and patterns of recurrence. RESULTS: At a median follow-up of 18.6 months (95% CI 15.9-21.2), PFS and OS were 7.5 (95% CI 6.7-8.3) and 13.9 (95% CI 10.9-16.9) months, respectively. On the univariate analyses, initial contact with the SVZ was a factor for poor prognosis for both PFS (6.1 vs. 8.7 months; p = 0.006) and OS (10.6 vs. 17.9 months; p = 0.037). On the multivariate analysis, tumor contact with the SVZ remained statistically significant for PFS, but not OS. Patients with SVZ-contacting tumors presented a higher rate of aggressive clinical progression (30.9% vs. 11.3%; p = 0.007) and contralateral relapse patterns (23.4% vs. 9.1%; p = 0.048). CONCLUSIONS: Our results suggest that glioblastoma contact with the SVZ appears to be an independent prognostic factor for poor PFS. The presence of an SVZ-contacting tumor was associated with more aggressive recurrences and a higher rate of contralateral relapses. These findings suggest that this variable may be a new prognostic factor in glioblastoma.

Correction to: SEOM clinical guidelines for anaplastic gliomas (2017).

The SEOM/GEINO clinical guidelines provide recommendations for radiological, and molecular diagnosis, treatment and follow-up of adult patients with anaplastic gliomas (AG). We followed the 2016 WHO classification which specifies the major diagnostic/prognostic and predictive value of IDH1/IDH2 missense mutations and 1p/19q codeletions in AG. The diagnosis of anaplastic oligoastrocytoma is discouraged. Surgery, radiotherapy and chemotherapy with PCV or TMZ are the first-line standard of care for AG with slight modifications according to molecular variables. A multidisciplinary team is highly recommended in the management of these tumors.

SEOM clinical guidelines for anaplastic gliomas (2017)

The SEOM/GEINO clinical guidelines provide recommendations for radiological, and molecular diagnosis, treatment and follow-up of adult patients with anaplastic gliomas (AG). We followed the 2016 WHO classification which specifies the major diagnostic/prognostic and predictive value of IDH1/IDH2 missense mutations and 1p/19q codeletions in AG. The diagnosis of anaplastic oligoastrocytoma is discouraged. Surgery, radiotherapy and chemotherapy with PCV or TMZ are the first-line standard of care for AG with slight modifications according to molecular variables. A multidisciplinary team is highly recommended in the management of these tumors (AU)

No disponible

SEOM clinical guidelines for anaplastic gliomas (2017).

The SEOM/GEINO clinical guidelines provide recommendations for radiological, and molecular diagnosis, treatment and follow-up of adult patients with anaplastic gliomas (AG). We followed the 2016 WHO classification which specifies the major diagnostic/prognostic and predictive value of IDH1/IDH2 missense mutations and 1p/19q codeletions in AG. The diagnosis of anaplastic oligoastrocytoma is discouraged. Surgery, radiotherapy and chemotherapy with PCV or TMZ are the first-line standard of care for AG with slight modifications according to molecular variables. A multidisciplinary team is highly recommended in the management of these tumors.

Results of a multicenter survey showing interindividual variability among neurosurgeons when deciding on the radicality of surgical resection in glioblastoma highlight the need for more objective guidelines

Purpose. We assessed agreement among neurosurgeons on surgical approaches to individual glioblastoma patients and between their approach and those recommended by the topographical staging system described by Shinoda. Methods. Five neurosurgeons were provided with pre-surgical MRIs of 76 patients. They selected the surgical approach [biopsy, partial resection, or gross total resection (GTR)] that they would recommend for each patient. They were blinded to each other’s response and they were told that patients were younger than 50 years old and without symptoms. Three neuroradiologists classified each case according to the Shinoda staging system. Results. Biopsy was recommended in 35.5-82.9%, partial resection in 6.6-32.9%, and GTR in 3.9-31.6% of cases. Agreement among their responses was fair (global kappa = 0.28). Nineteen patients were classified as stage I, 14 as stage II, and 43 as stage III. Agreement between the neurosurgeons and the recommendations of the staging system was poor for stage I (kappa = 0.14) and stage II (kappa = 0.02) and fair for stage III patients (kappa = 0.29). An individual analysis revealed that in contrast to the Shinoda system, neurosurgeons took into account T2/FLAIR sequences and gave greater weight to the involvement of eloquent areas. Conclusions. The surgical approach to glioblastoma is highly variable. A staging system could be used to examine the impact of extent of resection, monitor post-operative complications, and stratify patients in clinical trials. Our findings suggest that the Shinoda staging system could be improved by including T2/FLAIR sequences and a more adequate weighting of eloquent areas (AU)

No disponible

Results of a multicenter survey showing interindividual variability among neurosurgeons when deciding on the radicality of surgical resection in glioblastoma highlight the need for more objective guidelines.

PURPOSE: We assessed agreement among neurosurgeons on surgical approaches to individual glioblastoma patients and between their approach and those recommended by the topographical staging system described by Shinoda. METHODS: Five neurosurgeons were provided with pre-surgical MRIs of 76 patients. They selected the surgical approach [biopsy, partial resection, or gross total resection (GTR)] that they would recommend for each patient. They were blinded to each other's response and they were told that patients were younger than 50 years old and without symptoms. Three neuroradiologists classified each case according to the Shinoda staging system. RESULTS: Biopsy was recommended in 35.5-82.9%, partial resection in 6.6-32.9%, and GTR in 3.9-31.6% of cases. Agreement among their responses was fair (global kappa = 0.28). Nineteen patients were classified as stage I, 14 as stage II, and 43 as stage III. Agreement between the neurosurgeons and the recommendations of the staging system was poor for stage I (kappa = 0.14) and stage II (kappa = 0.02) and fair for stage III patients (kappa = 0.29). An individual analysis revealed that in contrast to the Shinoda system, neurosurgeons took into account T2/FLAIR sequences and gave greater weight to the involvement of eloquent areas. CONCLUSIONS: The surgical approach to glioblastoma is highly variable. A staging system could be used to examine the impact of extent of resection, monitor post-operative complications, and stratify patients in clinical trials. Our findings suggest that the Shinoda staging system could be improved by including T2/FLAIR sequences and a more adequate weighting of eloquent areas.

[Intraoperative complications of corticosubcortical mapping]. / Complicaciones intraoperatorias del mapeo corticosubcortical.

By looking through our cases and literature, an analysis of the surgical complications derived from direct cerebral stimulation under general anesthesia and local anesthesia and sedation was made. A retrospective descriptive study was performed including patients who were intervened in our centre from 2004 to 2008 and had the cortico-subcortical mapping technique. Common pre-operation variables were as follow: Age, sex, tumor localization and tumor's pathology; On patients intervened while awake, we collected the ASA, BMI and duration of the intervention. Afterwards, variable like epileptic attacks and cerebral edema were included in two groups. In addition, on those awake, respiratory and circulatory complications, local anesthesia toxicity, poor level of sedation, nausea and vomiting, pain and feeling uncomfortable with body posture were collected as well. A total of 20 patients had surgery. 10 of them were operated under local anesthesia and sedation with a mean age of 41 years, mean BMI of 26.8 and a pre-operatory ASA score of I or II ( except one patient with ASA III). The mean time duration of the surgical procedure was 5 hours and 20 minutes. On the other side, 10 patients were intervened with general anesthesia with a mean age of 55 years. There were no cases of cerebral edema in either group, although in 4 patients had epileptic attacks which resolved with cold saline irrigation. Five patients with local anesthesia and sedation did not have any complication, 2 patients showed desaturation episodes without further complications, three manifested hypertension episodes and two signs of feeling uncomfortable with body posture. None of the intra-operatory complications registered interfered wit the overall surgical procedure. This is a safe technique if performed following recommended indications and parameters. Regarding complications, respiratory complications are the most common and the most dangerous, as they can influence in the surgical procedure for difficult cases.

Complicaciones intraoperatorias del mapeo corticosubcortical / Intraoperative complications of corticosubcortical mapping

Mediante una revisión de nuestra casuística y dela literatura analizamos las complicaciones intraoperatoriasderivadas del uso de las estimulaciones cerebralesdirectas bajo anestesia general y anestesialocal y sedación. Se realizó un estudio retrospectivodescriptivo de los pacientes intervenidos (2004-2008)en que se utilizó la técnica del mapeo corticosubcortical.Se determinaron como variables preoperatoriascomunes: edad, sexo, localización tumoral, anatomíapatológica, y en los pacientes operados despiertos, seregistró el ASA, IMC y duración de la intervención.En los dos grupos se constataron la aparición de edemacerebral o crisis comiciales. En los pacientes despiertosse registró además las complicaciones respiratorias,hemodinámicas, toxicidad por anestésico local, nivelinadecuado de sedación, náuseas/vómitos, dolor eincomodidad postural. Bajo anestesia local y sedaciónse operaron 10, de 41 años de edad media, IMC mediode 26,8 y un ASA preoperatorio de I o II . La duraciónmedia de la intervención fue de 5 horas y 20 minutos.Mediante anestesia general se intervinieron 10 pacientes,de 55 años de media. En ningún caso de los dosgrupos se constató edema cerebral, 4 pacientes presentaroncrisis comiciales (autolimitadas con irrigación desuero frío). En 5 pacientes con anestesia local y sedaciónno registramos ninguna complicación, 2 pacientes episodiosde desaturación sin complicaciones, 3 episodiosde hipertensión y 2 incomodidad postural. Ninguna delas complicaciones intraoperatorias que registramosinterfirió en el desarrollo de la cirugía. Es una técnicasegura si se realiza siguiendo las indicaciones y losparámetros recomendados. Las crisis y complicacionesrespiratorias son las complicaciones más frecuentes ya su vez las más temidas, puesto que pueden influir encasos problemáticos en el proceso de la cirugía (AU)

By looking through our cases and literature, ananalysis of the surgical complications derived fromdirect cerebral stimulation under general anesthesiaand local anesthesia and sedation was made. A retrospectivedescriptive study was performed includingpatients who were intervened in our centre from 2004to 2008 and had the cortico-subcortical mapping technique.Common pre-operation variables were as follow:Age, sex, tumor localization and tumor’s pathology; Onpatients intervened while awake, we collected the ASA,BMI and duration of the intervention. Afterwards,variable like epileptic attacks and cerebral edema wereincluded in two groups. In addition, on those awake,respiratory and circulatory complications, local anesthesiatoxicity, poor level of sedation, nausea and vomiting,pain and feeling uncomfortable with body posturewere collected as well. A total of 20 patients had surgery.10 of them were operated under local anesthesia andsedation with a mean age of 41 years, mean BMI of 26.8and a pre-operatory ASA score of I or II ( except onepatient with ASA III). The mean time duration of thesurgical procedure was 5 hours and 20 minutes. On theother side, 10 patients were intervened with generalanesthesia with a mean age of 55 years. There were nocases of cerebral edema in either group, although in 4patients had epileptic attacks which resolved with coldsaline irrigation. Five patients with local anesthesiaand sedation did not have any complication, 2 patientsshowed desaturation episodes without further complications,three manifested hypertension episodes and (..) (AU)

[Intracranial meningiomas in children: report of 10 cases]. / El meningioma en edad pediátrica. Revisión de 10 casos.

The occurrence of meningiomas in children is rare, accounting for less than 5% of tumors of the central nervous system in childhood. This is a retrospective study of 10 patients with CNS meningiomas. The goal of this study was to determine the epidemiology, clinical and radiological features, and long-term outcome of meningiomas. The results ware compared with those reported in the literature.

El meningioma en edad pediátrica. Revisión de 10 casos / Intracranial meningiomas in children: report of 10 cases

La presencia de meningiomas en la edad pediátricaes relativamente rara, representan menos del 5% detodos los tumores del sistema nervioso central en esteestadio de la vida.Hemos realizado un estudio retrospectivo de 10 casosde meningiomas en pacientes pediátricos analizando losfactores epidemiológicos, clínicos y radiológicos, así comoel pronóstico a largo plazo de nuestros pacientes.Los resultados se comparan con aquéllos reportados enla literatura (AU)

The occurrence of meningiomas in children is rare,accounting for less than 5% of tumors of the centralnervous system in childhood. This is a retrospectivestudy of 10 patients with CNS meningiomas. The goalof this study was to determine the epidemiology, clinicaland radiological features, and long-term outcome ofmeningiomas The results ware compared with thosereported in the literature (AU)

[Comparison [corrected] of Chiari I malformation treatment using suboccipital craniectomy and posterior arch of C1 resection with or without dural graft]. / Comparación del tratamiento de la malformación de Chiari tipo I mediante craniectomía suboccipital y resección del arco posterior de C1 con o sin duroplastia.

UNLABELLED: There are various surgical approaches to treat Chiari I malformation. In spite of the good clinical results that are reported with most of them, there is still controversy about the optimal treatment of this pathology. OBJECTIVE: To compare the clinical and radiological results of surgical treatment of the Chiari I malformation with suboccipital craniectomy, posterior arch of C1 resection with or without dural graft, analyzing clinical and radiological findings and describing the complications. MATERIAL AND METHODS: Retrospectively clinical cases series of patients who underwent Chiari I malformation surgery between 1998 and 2006 in the Hospital Germans Trias i Pujol in Badalona. The inclusion criteria consisted in: patients older than 18 years, who have had surgery in our hospital, detailed neurological examination before and after surgery (calculating the EDSS scale punctuation), craniospinal magnetic resonance imaging before and after surgery and minimal follow up period of 6 months. The election of the surgical approach was left to the discretion of the main surgeon. Patients were divided in two groups depending of the surgical technique: Group A (with dural graft) and Group B (without dural graft). To evaluate the morphological results in both groups, measurements of the position of the fastigium above a basal line in the midsagittal T1 weighted magnetic resonance images were obtained. In patients with syringomyelia, siringo-to-cord ratio was measured before and after surgery. To evaluate the clinical results, neurological examination was recorded in both groups before and after surgery. RESULTS: The mean age of Group A patients was 47 (-/+12.89) years, and of Group B was 38.3 (-/+7.77) years. Mean follow up period was 2.48 (-/+2.44) years in Group A and 4.2 (-/+4.46) in Group B. Creation of an artificial cisterna magna was observed en 35.7% of Group A patients and only in 3.5% of Group B patients (p=0.022). In 8 patients front Group A, 8 patients (28.6%) an upward migration of the cerebellum was seen, whereas any of the Group B patients presented it (p=0.022) Siringo-to-cord ratios were decreased in both groups without significant differences. All of the Group A patients improved their clinical exploration. In Group B, 60% of the patients improved and the 40% left maintained clinical stability. Any patient worsened. All patients that maintained clinical stability belonged to Group B, the differences between the two groups were statistically significant (p=0.04). Five patients presented immediate surgical complications (2 pseudomeningoceles, 2 meningitis and 1 hydrocephalus). All this patients where operated with dural graft (p=0.049). CONCLUSIONS: According to our study, suboccipital craniectomy with resection of the posterior arch of C1 and dural graft shows better clinical and radiological results than without dural graft. Nevertheless this technique can increase the incidence of surgical complications.

Comparación del tratamiento de la malformación de Chiari tipo I mediante craniectomía suboccipital y resección del arco posterior de C1 con o sin duroplastia / Comparation of Chiari I malformation treatment using suboccipital craniectomy and posterior arch of C1 resection with or without dural graft

Existen múltiples tratamientos descritos para la malformación de Chiari tipo I. Se reportan buenos resultados clínicos con la mayoría de las variantes. Aún así, sigue habiendo controversia acerca del tratamiento óptimo de esta entidad. Objetivo. Comparar los resultados clínico-radiológicos del tratamiento quirúrgico de la malformación de Chiari tipo I mediante craniectomía suboccipital, resección del arco posterior de C1 con o sin duroplastia, analizando las variables clínicas, radiológicas y describiendo las complicaciones. Material y métodos. Se realizó un estudio retrospectivo de los pacientes intervenidos en nuestro centro entre los años 1998 y 2006. La muestra cumplía los siguientes criterios de inclusión: pacientes mayores de 18 años, que hubieran sido intervenidos en nuestro centro en todas las ocasiones, examen neurológico preoperatorio y de control postoperatorio (calculando su puntuación en la escala EDSS), estudio de imagencraneo espinal preoperatorio y postoperatorio y tiempomínimo de seguimiento clínico de 6 meses. Los pacientes se intervinieron con una u otra técnicaen función del criterio del cirujano principal. Dividimosa los pacientes en dos grupos según la técnica utilizada: Grupo A (intervenidos mediante duroplastia) y grupo B (intervenidos sin duroplastia). Para evaluar los resultados radiológicos en los dos grupos se midieron en la resonancia magnética, antes y después de la cirugía: la migración cerebelos a siguiendo el método de Duddy y Williams y la ratio siringo espinal en los pacientes con siringomielia. Para evaluar el resultado clínico, se recogió en los dos grupos la exploración neurológica antes y después de la cirugía. Resultados. La edad media de los pacientes del grupo A fue de 47 (±12,89) años, mientras que la del grupo B fue de 38,30 (±7,77) años. El tiempo medio de seguimiento de los pacientes del grupo A fue de 2,48 (...)

There are various surgical approaches to treat ChiariI malformation. In spite of the good clinical results that are reported with most of them, there is still controversy about the optimal treatment of this patology.Objective. To compare the clinical and radiologicalresults of surgical treatment of the Chiari I malformation with suboccipital craniectomy, posterior arch of C1 resection with or without dural graft, analyzing clinical and radiological findings and describing the complications.Material and methods. Retrospectively clinical casesseries of patients who underwent Chiari I malformationsurgery between 1998 and 2006 in the Hospital GermansTrias i Pujol in Badalona. The inclusion criteriaconsisted in: patients older than 18 years, who have hadsurgery in our hospital, detailed neurological examination before and after surgery (calculating the EDSS scale punctuation), craniospinal magnetic resonanceimaging before and after surgery and minimal followup period of 6 months.The election of the surgical approach was left to thediscretion of the main surgeon.Patients were divided in two groups depending ofthe surgical technique: Group A (with dural graft)and Group B (without dural graft). To evaluate themorphological results in both groups, measurementsof the position of the fastigium above a basal line in the midsagittal T1 weighted magnetic resonance imageswere obtained. In patients with syringomyelia, siringoto-cord ratio was measured before and after surgery. Toevaluate the clinical results, neurological examinationwas recorded in both groups before and after surgery.Results. The mean age of Group A patients was 47(±12,89) years, and of Group B was 38,3 (±7,77) years.Mean follow up period was 2,48 (...)

Clinical course of high-grade glioma patients with a "biopsy-only" surgical approach: a need for individualised treatment.

INTRODUCTION: 'Biopsy-only' high-grade glioma (HGG) patients get limited benefit from post-operative treatments, and as a group, negatively impact median survival outcomes. MATERIAL AND METHODS: We retrospectively evaluated clinical characteristics, treatment and overall survival of HGG patients with a 'biopsy- only' surgical approach diagnosed between 1997 and 2005 at a University Hospital in Spain. RESULTS: In 31% of 294 suspected gliomas, only a diagnostic biopsy was undertaken. Reasons for 'biopsy-only' for all patients were either location in eloquent areas: (motor area 18.7%, language area 25,3%, basal ganglia 7.7%, visual area 4.4%) or extension of the disease (corpus callosum invasion 14.3% and multicentricity/multifocality 28.6%). Seventy-four patients (80.4%) were HGG: 26% of all grade IV and 49% of all grade III tumours. For these patients, post-operative Karnofsky Performance Status of over 70%, median age and median survival were, respectively: 64 and 70%, 60.7 and 57 years old, and 23.1 and 42.7 weeks (p=0.0006). Patients lived longer if post-operative treatment was given, in all grades (p<0.0001). Nineteen patients (25.6%) died within 42 days after surgery. Only 60% of them initiated radiotherapy and 10% of them did not complete it. However, tumour grade, radiotherapy and temozolomide- based chemotherapy were independently associated with longer survival in multivariate analysis (p<0.05). CONCLUSION: Almost one third of HGG patients can undergo only a biopsy and not debulking surgery. Although radiotherapy improves survival, only 50% of them complete the treatment. An individualised approach to these patients is needed to facilitate a correct analysis of therapy results. New therapies must be investigated in these patients.

Clinical course of high-grade glioma patients with a "biopsy-only" surgical approach: a need for individualised treatment

INTRODUCTION: 'Biopsy-only' high-grade glioma (HGG) patients get limited benefit from post-operative treatments, and as a group, negatively impact median survival outcomes. MATERIAL AND METHODS: We retrospectively evaluated clinical characteristics, treatment and overall survival of HGG patients with a 'biopsy- only' surgical approach diagnosed between 1997 and 2005 at a University Hospital in Spain. RESULTS: In 31% of 294 suspected gliomas, only a diagnostic biopsy was undertaken. Reasons for 'biopsy-only' for all patients were either location in eloquent areas: (motor area 18.7%, language area 25,3%, basal ganglia 7.7%, visual area 4.4%) or extension of the disease (corpus callosum invasion 14.3% and multicentricity/multifocality 28.6%). Seventy-four patients (80.4%) were HGG: 26% of all grade IV and 49% of all grade III tumours. For these patients, post-operative Karnofsky Performance Status of over 70%, median age and median survival were, respectively: 64 and 70%, 60.7 and 57 years old, and 23.1 and 42.7 weeks (p=0.0006). Patients lived longer if post-operative treatment was given, in all grades (p<0.0001). Nineteen patients (25.6%) died within 42 days after surgery. Only 60% of them initiated radiotherapy and 10% of them did not complete it. However, tumour grade, radiotherapy and temozolomide- based chemotherapy were independently associated with longer survival in multivariate analysis (p<0.05). CONCLUSION: Almost one third of HGG patients can undergo only a biopsy and not debulking surgery. Although radiotherapy improves survival, only 50% of them complete the treatment. An individualised approach to these patients is needed to facilitate a correct analysis of therapy results. New therapies must be investigated in these patients (AU)

Compound-specific carbon isotope analysis of volatile organic compounds in water using solid-phase microextraction.

The compound-specific isotope analysis technique in conjunction with solid-phase microextraction using a carboxen-polydimethylsiloxane fiber was tested and implemented for isotopes analyses of organic compounds aiming for environmental application in contaminated groundwater. delta(13)C values of several chlorinated methanes and ethenes, toluene and chlorobenzene were determined using a gas chromatograph coupled to an isotope ratio mass spectrometer through a combustion interface. Direct and headspace solid-phase microextraction (D-SPME, HS-SPME) methods were tested in order to determine the optimum conditions to obtain reproducible delta(13)C values at very low concentration (microg/L range) and, to elucidate the carbon isotopic effects associated with the competitive extraction. For D-SPME, higher accuracy and precision of delta(13)C results were obtained with no salted aqueous standards. Despite that the delta(13)C of those compounds analyzed with both methods showed similar precision (<0.5 per thousand) and accuracy, the highest sensitivity was reached with HS-SPME. Furthermore, the delta(13)C values of cis-1,2-dichloroethylene, chorinated methanes and aromatic compounds obtained using HS-SPME showed measurable deviations with respect to the isotopic composition of pure phase compounds, however, these deviations are constant according to the analytical uncertainties, indicating that they are not affected by competitive extraction, and they could be corrected using standard correction technique based on internal calibrated standards.

[Spinal epidural hematomas. Prognostic factors in a series of 22 cases and a proposal for management]. / Revisión de 22 casos de hematomas epidurales espinales. Factores pronósticos y manejo terapéutico.

INTRODUCTION: Spontaneous and non-spontaneous spinal epidural hematoma (SEH) is a rare condition in neurosurgical practice. It presents as an acute spinal cord compression and usually requires emergent surgical decompression. Recently non-surgical treatment (corticoid therapy) has been proposed in selected cases of SEH with good neurological recovery. OBJECTIVES: To identify the prognostic factors of this condition. A treatment management based upon our results is proposed. MATERIAL AND METHODS: Between 1985 and 2001, 22 patients suffering SEH were treated at our Department. Age, sex, initial neurological condition (evaluated using the Frankel grading scale), surgical timing, radiological data such as location, extension and degree of radiological cord compression, anticoagulation or antiplatelet therapy, epidural anesthesia and previous spinal surgery were analyzed in order to find prognostic factors. Finally, conservative or surgical treatment as well as final neurological condition were also considered for the analysis. RESULTS: The average age was 69 years with a male preponderance (72.7%). Surgical decompression was done in 17 cases, most of them (11 cases) presenting with high neurological deficit (Frankel A-B). Conservative treatment was used on 5 patients. Operated patients showed a larger degree of neurological recovery. The incidence of post-operative complications was of 13%. CONCLUSIONS: This study shows the efficiency of SEH surgical evacuation performed within the first 24 hours, particularly when the patient presents a severe neurological deficit (Frankel A-B). Patients presenting minimal neurological involvement (Frankel D-E) can be managed successfully with conservative treatment.

Revisión de 22 casos de hematomas epidurales espinales. Factores pronósticos y manejo terapéutico / Spinal epidural hematomas. Prognostic factors in a series of 22 cases and a proposal for management

Introducción. El hematoma epidural espinal (HEE) es una patología poco frecuente, causante de compresión medular aguda, clásicamente considerada como una urgencia quirúrgica. Recientemente se ha propuesto el tratamiento conservador cuando existe afectación neurológica leve, con buenos resultados funcionales finales. Objetivos. Determinar los factores pronósticos de esta entidad y proponer un manejo terapéutico. Material y métodos. Entre 1985 y 2001 han sido tratados, en el Servicio de Neurocirugía del Hospital Universitario de Bellvitge (HUB), 22 pacientes diagnosticados de HEE. Se han analizado una serie de variables: edad, sexo, déficit neurológico inicial (según la Escala de Frankel), tiempo de evolución hasta el tratamiento, así como la localización, extensión y grado de compresión medular radiológica. La toma de medicación anticoagulante o antiagregante, la existencia de anestesia epidural o cirugía espinal previa fueron, asimismo, factores tomados en consideración para el análisis final.Se ha recogido el tipo de tratamiento (médico o quirúrgico) y se han evaluado las secuelas, así como el grado de afectación neurológica final. Resultados. La serie se compone de 22 pacientes, con un 72.7 por ciento de varones y una mediana de edad es de 69 años. El tratamiento quirúrgico se practicó en 17 casos, la mayoría de los cuales (11 casos) presentaban un déficit neurológico grave (Frankel A-B). Se realizó tratamiento conservador en 5 pacientes, la mayoría (4 de 5) presentaban afectación neurológica leve (Frankel D). Los pacientes intervenidos presentaron mayor grado de mejoría de su déficit neurológico inicial. El índice de complicaciones post-quirúrgicas fue del 13 por ciento. Conclusiones: El tratamiento quirúrgico precoz (primeras 24 horas) mejora el pronóstico en los pacientes que presentan afectación neurológica, especialmente de grado severo (FrankelA-B). Los pacientes asintomáticos o con afectación neurológica leve (Frankel D-E) pueden ser tratados inicialmente de forma conservadora (AU)

Can spider monkeys (Ateles geoffroyi) discriminate vocalizations of familiar individuals and strangers?

In a field experiment, tape-recorded vocalizations of spider monkeys (Ateles geoffroyi) were played back to investigate whether individuals were able to discriminate between group members and strangers. Monkeys responded remarkably similarly in the two cases, with no significant difference found between the numbers of calls given by an individual, or the types of call given. However, a group was more likely to give some vocal reaction when hearing a stranger's call than when hearing one from an individual of their own community. Further, the only instances in which agonistic territorial behaviours occurred were in reaction to strangers' playbacks. No significant effects on the response given were produced by the sex of the caller, the location and time of day of the broadcast, the size of the subgroup hearing the call or the activity in which they were involved. These results are discussed with respect to acoustic, social and ecological factors that may lead to the apparent lack of vocal discrimination of strangers within the community range.

Imitative learning of artificial fruit processing in children (Homo sapiens) and chimpanzees (Pan troglodytes).

Observational learning in chimpanzees and young children was investigated using an artificial fruit designed as an analog of natural foraging problems faced by primates. Each of 3 principal components could be removed in 2 alternative ways, demonstration of only one of which was watched by each subject. This permitted subsequent imitation by subjects to be distinguished from stimulus enhancement. Children aged 2-4 years evidenced imitation for 2 components, but also achieved demonstrated outcomes through their own techniques. Chimpanzees relied even more on their own techniques, but they did imitate elements of 1 component of the task. To our knowledge, this is the first experimental evidence of chimpanzee imitation in a functional task designed to simulate foraging behavior hypothesized to be transmitted culturally in the wild.