Suboptimal interventional conditions for the occlusion of ruptured intracranial aneurysms do not increase periprocedural complications and poor clinical outcomes.

BACKGROUND AND OBJECTIVE: Occluding a ruptured intracranial aneurysm as early as possible may entail certain periprocedural conditions that compromise the outcome. The aim of the present study was to evaluate the effectiveness, safety, and clinical outcome of endovascular coiling procedures performed on an emergency basis under potentially suboptimal conditions, and to compare results with those from scheduled procedures under potentially optimal conditions. METHODS: Interventions performed on 66 SAH patients were retrospectively analysed by classifying them into two groups: under emergency (within three hours from diagnosis or during non-standard working hours) or scheduled conditions. A binary logistic regression analysis was also performed to identify characteristics associated with poor outcomes. RESULTS: No differences in effectiveness, periprocedural complications, or clinical outcomes were found between the two groups. Rebleeding was detected in 4.8 % of the emergency interventions and 2.2 % of the scheduled interventions. Multivariate analysis identified age and Hunt and Hess grade, but no conditions of treatment, as the factors associated to poor outcome. CONCLUSION: Suboptimal interventional conditions for occluding ruptured intracranial aneurysms, such as performing procedures outside of standard working hours or within three hours of diagnosis, do not result in increased periprocedural complications and poor clinical outcomes compared with scheduled procedures under potentially optimal conditions. These results suggest the need for treatment to be provided as soon as possible.

[Analysis of judicial sentences against neurosurgeons resolved in second court of justice in Spain in the period from 1995 to 2007]. / Análisis de las sentencias judiciales contra neurocirujanos resueltas en segunda instancia en España entre 1995 y 2007.

OBJECTIVES: With the aim of identifying the factors related to sentences against neurosurgeons, we have analyzed all the sentences issued in the second court of justice in Spain against neurosurgeons in the period from 1995 to 2007. MATERIAL AND METHODS: Of a total of 1899 sentences of the second or last appeal, during the period from 1995 to 2007 issued in Spain, 61 were chosen which fulfill the criteria to be included in our study. 25 variables were included on the record of compiled data. A complete descriptive and comparative study was elaborated, as well as an analysis of the type of suits, circumstances, and professionals involved. RESULTS: In a third of the cases, complete malpraxis was identified. In regards to the sentences, they were absolved in approximately half the cases, resolved with one fifth of the cases being penal, and four fifths with compensation. Indemnity quantities range from 60,000 to 600,000euro. Deficiency of information or consent was noted in 17% of lawsuits. 62.5% of operations in our sample were on the anatomic region of the vertebral column followed in frequency by the cranial region with 28.6%. Consequences of surgical procedure included major permanent sequelae in 40% of the cases and death in 22%. CONCLUSIONS: It is wise to invest time to deal with patients, including the verbal informed consent, which must be confirmed by the written informed consent form. It is also important to leave a written proof of medical praxis, both related to surgical records and to diagnosis and follow-up of the patient. Procedures with a lower life-threatening risk should not be underestimated, since they comprise the greatest demanded group. The greatest amount of demands is related to economic reimbursement, especially in private practice.

NG2 and GFAP co-expression after differentiation in cells transfected with mutant GFAP and in undifferentiated glioma cells. / Coexpresión de NG2/GFAP tras la diferenciación en células transfectadas con las mutaciones de GFAP y en células procedentes de gliomas indiferenciados.

INTRODUCTION: Alexander disease is a rare disorder caused by mutations in the gene coding for glial fibrillary acidic protein (GFAP). In a previous study, differentiation of neurospheres transfected with these mutations resulted in a cell type that expresses both GFAP and NG2. OBJECTIVE: To determine the effect of molecular marker mutations in comparison to undifferentiated glioma cells simultaneously expressing GFAP and NG2. METHODS: We used samples of human glioblastoma (GBM) and rat neurospheres transfected with GFAP mutations to analyse GFAP and NG2 expression after differentiation. We also performed an immunocytochemical analysis of neuronal differentiation for both cell types and detection of GFAP, NG2, vimentin, Olig2, and caspase-3 at 3 and 7 days from differentiation. RESULTS: Both the cells transfected with GFAP mutations and GBM cells showed increased NG2 and GFAP expression. However, expression of caspase-3-positive cells was found to be considerably higher in transfected cells than in GBM cells. CONCLUSIONS: Our results suggest that GFAP expression is not the only factor associated with cell death in Alexander disease. Caspase-3 expression and the potential role of NG2 in increasing resistance to apoptosis in cells co-expressing GFAP and NG2 should be considered in the search for new therapeutic strategies for the disease.

Inhibition of adult hippocampal neurogenesis disrupts contextual learning but spares spatial working memory, long-term conditional rule retention and spatial reversal.

Neurogenesis in the adult dentate gyrus (DG) of the hippocampus has been implicated in neural plasticity and cognition but the specific functions contributed by adult-born neurons remain controversial. Here, we have explored the relationship between adult hippocampal neurogenesis and memory function using tasks which specifically require the participation of the DG. In two separate experiments several groups of rats were exposed to fractionated ionizing radiation (two sessions of 7 Gy each on consecutive days) applied either to the whole brain or focally, aiming at a region overlying the hippocampus. The immunocytochemical assays showed that the radiation significantly reduced the expression of doublecortin (DCX), a marker for immature neurons, in the dorsal DG. Ultrastructural examination of the DG region revealed disruption of progenitor cell niches several weeks after the radiation. In the first experiment, whole-brain and focal irradiation reduced DCX expression by 68% and 43%, respectively. Whole-brain and focally-irradiated rats were unimpaired compared with control rats in a matching-to-place (MTP) working memory task performed in the T-maze and in the long-term retention of the no-alternation rule. In the second experiment, focal irradiation reduced DCX expression by 36% but did not impair performance on (1) a standard non-matching-to-place (NMTP) task, (2) a more demanding NMTP task with increasingly longer within-trial delays, (3) a long-term retention test of the alternation rule and (4) a spatial reversal task. However, rats irradiated focally showed clear deficits in a "purely" contextual fear-conditioning task at short and long retention intervals. These data demonstrate that reduced adult hippocampal neurogenesis produces marked deficits in the rapid acquisition of emotionally relevant contextual information but spares spatial working memory function, the long-term retention of acquired spatial rules and the ability to flexibly modify learned spatial strategies.

[Experimental models of traumatic brain injury]. / Modelos experimentales de traumatismo craneoencefálico.

AIM: To provide a summary of the different experimental models of traumatic brain injury (TBI) designed under both in vivo and in vitro conditions. A comprehensible review of the specific types of brain lesions induced, as well as the technical details to reproduce each model at the laboratory is given. DEVELOPMENT: Outcome of patients suffering from a TBI has significantly improved with the rapid application of vital supporting measures in addition to a strict control of blood and intracranial pressure at the intensive care units. However no specific treatment for post-traumatic brain lesions has proven as efficacious in the clinical settings. A deeper knowledge of the physiopathological events associated with TBI is necessary for the development of new specific therapies. Due to the heterogeneity of the human TBI, each experimental model has been designed to reproduce a different type of brain lesion. Experimental TBI models allow the study of the dynamic evolution of brain injuries under controlled conditions. Usefulness of experimental models is limited by their reliability and reproducibility among different researchers. Small rodents have been the preferred animals to reproduce TBI injuries, mainly due to the similar cerebral physiology shared by these animals and the human beings. CONCLUSION: The use of experimental models of TBI is the most appropriate tool to study the mechanisms underlying this type of injury. However their simplicity precludes an exact reproduction of the heterogeneous cerebral damage observed in clinical settings. This could be the main reason for the discrepancies observed in the therapeutic effects of treatments between experimental and clinical studies.

Morphologic Features on MR Imaging Classify Multifocal Glioblastomas in Different Prognostic Groups.

BACKGROUND AND PURPOSE: Multifocal glioblastomas (ie, glioblastomas with multiple foci, unconnected in postcontrast pretreatment T1-weighted images) represent a challenge in clinical practice due to their poor prognosis. We wished to obtain imaging biomarkers with prognostic value that have not been found previously. MATERIALS AND METHODS: A retrospective review of 1155 patients with glioblastomas from 10 local institutions during 2006-2017 provided 97 patients satisfying the inclusion criteria of the study and classified as having multifocal glioblastomas. Tumors were segmented and morphologic features were computed using different methodologies: 1) measured on the largest focus, 2) aggregating the different foci as a whole, and 3) recording the extreme value obtained for each focus. Kaplan-Meier, Cox proportional hazards, correlations, and Harrell concordance indices (c-indices) were used for the statistical analysis. RESULTS: Age (P < .001, hazard ratio = 2.11, c-index = 0.705), surgery (P < .001, hazard ratio = 2.04, c-index = 0.712), contrast-enhancing rim width (P < .001, hazard ratio = 2.15, c-index = 0.704), and surface regularity (P = .021, hazard ratio = 1.66, c-index = 0.639) measured on the largest focus were significant independent predictors of survival. Maximum contrast-enhancing rim width (P = .002, hazard ratio = 2.05, c-index = 0.668) and minimal surface regularity (P = .036, hazard ratio = 1.64, c-index = 0.600) were also significant. A multivariate model using age, surgery, and contrast-enhancing rim width measured on the largest foci classified multifocal glioblastomas into groups with different outcomes (P < .001, hazard ratio = 3.00, c-index = 0.853, median survival difference = 10.55 months). Moreover, quartiles with the highest and lowest individual prognostic scores based on the focus with the largest volume and surgery were identified as extreme groups in terms of survival (P < .001, hazard ratio = 18.67, c-index = 0.967). CONCLUSIONS: A prognostic model incorporating imaging findings on pretreatment postcontrast T1-weighted MRI classified patients with glioblastoma into different prognostic groups.

The hippocampal dentate gyrus is essential for generating contextual memories of fear and drug-induced reward.

The hippocampus is believed to play a role in processing information relative to the context in which emotionally salient experiences occur but evidence on the specific contribution of the hippocampal dentate gyrus (DG) to these processes is limited. Here, we have used two classical behavioral paradigms to study the participation of the dorsal DG in context-conditioned reward and context-conditioned fear. Rats received intra-hippocampal vehicle or colchicine injections (4 microg/microl solution; 0.2 microl injections at 10 sites) that damaged the DG but spared other hippocampal subfields. In the first experiment, we used a place conditioning procedure pairing cocaine exposure (20 mg/kg, i.p.) with a specific context and vehicle treatment with another. While rats with sham lesions exhibited preference for the cocaine-paired context following conditioning, rats with lesions of the DG showed no evidence of cocaine-induced place preference. In the second experiment, rats with sham or colchicine lesions received a foot shock in a given context and conditioned freezing was measured upon reexposure to the shock-paired context (2, 24, 48 and 96 h after conditioning). Rats with sham lesions exhibited high levels of conditioned freezing when exposed to the conditioning context but rats with lesions of the DG showed impaired conditioning, behaving as controls that had experienced shock in a different context. These observations indicate that the integrity of the DG is essential for establishing a coherent representation of the context to which emotional experiences, either hedonic or aversive, are bound.

Primary immunoblastic B-cell lymphoma of the cranial vault.

We present the first reported patient with primary immunoblastic non-Hodgkin's lymphoma of the cranial vault, with a fatal outcome in spite of complete surgical removal.

Histological changes in the rat brain and spinal cord following prolonged intracerebroventricular infusion of cerebrospinal fluid from amyotrophic lateral sclerosis patients are similar to those caused by the disease. / La infusión intracerebroventricular prolongada de líquido cefalorraquídeo procedente de pacientes con esclerosis lateral amiotrófica provoca cambios histológicos en el cerebro y la médula espinal de la rata similares a los hallados en la enfermedad.

INTRODUCTION: Cerebrospinal fluid (CSF) from amyotrophic lateral sclerosis (ALS) patients induces cytotoxic effects in in vitro cultured motor neurons. MATERIAL AND METHODS: We selected CSF with previously reported cytotoxic effects from 32 ALS patients. Twenty-eight adult male rats were intracerebroventricularly implanted with osmotic mini-pumps and divided into 3 groups: 9 rats injected with CSF from non-ALS patients, 15 rats injected with cytotoxic ALS-CSF, and 4 rats injected with a physiological saline solution. CSF was intracerebroventricularly and continuously infused for periods of 20 or 43days after implantation. We conducted clinical assessments and electromyographic examinations, and histological analyses were conducted in rats euthanised 20, 45, and 82days after surgery. RESULTS: Immunohistochemical studies revealed tissue damage with similar characteristics to those found in the sporadic forms of ALS, such as overexpression of cystatinC, transferrin, and TDP-43 protein in the cytoplasm. The earliest changes observed seemed to play a protective role due to the overexpression of peripherin, AKTpan, AKTphospho, and metallothioneins; this expression had diminished by the time we analysed rats euthanised on day 82, when an increase in apoptosis was observed. The first cellular changes identified were activated microglia followed by astrogliosis and overexpression of GFAP and S100B proteins. CONCLUSION: Our data suggest that ALS could spread through CSF and that intracerebroventricular administration of cytotoxic ALS-CSF provokes changes similar to those found in sporadic forms of the disease.

Spared place and object-place learning but limited spatial working memory capacity in rats with selective lesions of the dentate gyrus.

We studied the cognitive performance of rats with colchicine-induced lesions of the hippocampal dentate gyrus (DG) on a range of spatial, non-spatial and mixed spatial/procedural tasks. Rats were assigned to three experimental groups receiving large colchicine lesions (7 microg per hippocampus), small colchicine lesions (1.75 microg per hippocampus) or sham lesions. Stereological estimates of cell density indicated that the colchicine treatments induced dose-dependent damage to the DG, while sparing in large part other hippocampal subfields. Remarkably, the behavioural results showed that the colchicine lesions did not affect the performance of rats in an object discrimination task, in an object-place associative task in which a familiar object was displaced from a given position nor in a spontaneous spatial discrimination task performed in the T-maze. However, rats in both lesion groups were severely impaired in a reinforced non-matching-to-position working memory task conducted in the T-maze. Importantly, performance in the working memory task correlated strongly with cell density in the DG but not with cell density in the CA1 and CA3 areas. Only rats with large-lesions showed a transient deficit in a reinforced rule-based conditional discrimination task. These data demonstrated that rats with selective lesions of the DG readily acquire and retain neural representations relative to objects and places but are specifically impaired in their ability to update rapidly and flexibly spatial information that is essential to guide goal-directed actions.

Influence of the substrate's hydrophilicity on the in vitro Schwann cells viability.

A series of polymeric biomaterials including poly (methyl acrylate) (PMA), chitosan (CHT), poly(ethyl acrylate) (PEA), poly(hydroxyethyl acrylate) (PHEA), and a series of random copolymers containing ethyl acrylate and hydroxyethyl acrylate monomeric units were tested in vitro as culture substrates and compared for their impact on the proliferation and expansion of Schwann cells (SCs). Immunocytochemical staining assay and scanning electron microscopy techniques were applied to perform a quantitative analysis to determine the correct maintenance of the cultured glial cells on the different biomaterials. The results strongly suggest that cell attachment and proliferation is influenced by the substrate's surface chemistry, and that hydrophobic biomaterials based on PMA, PEA, and the copolymers PEA and PHEA in a narrow composition window are suitable substrates to promote cell attachment and proliferation of SCs in vitro.

Fatal outcome related to carmustine implants in glioblastoma multiforme.

Following the resection of newly diagnosed or recurrent glioblastomas, local implantation of carmustine-impregnated biodegradable wafers (Gliadel) in the resection cavity constitutes an adjuvant therapy that can improve the possibilities of survival. However, some precautions should be taken regarding Gliadel implantation. We report three cases in whom patients with glioblastoma multiforme were implanted with fibrin glue-secured Gliadel after the lateral ventricles had been opened, and who later developed severe hydrocephalus leading to death. Although Gliadel may be an important adjunct to treatment, opening of the ventricles during surgery as part of its application should be considered a contra-indication.

[Present status of psychosurgery in Spain]. / Estado actual de la psicocirugía en España.

In order to know the present activity of psychosurgery in Spain, and the opinion of neurosurgeons relative to it, a survey was designed and applied to all active neurosurgeons in our country. We obtained data from at least one neurosurgeon from the 74 neurosurgical centers in Spain (response rate= 100%). Only 6 neurosurgeons performed psychosurgical interventions. In total, 121 psychosurgeries were performed between 1999 and 2003, 75.7% of them in private centers. The most frequent indication is obsessive-compulsive disorder and the most frequent technique is anterior capsulotomy, although techniques and indications differ among the practising neurosurgeons. Those not performing them cite lack of patient referral (54.4%) or unexperience (36.8%) as the causes. A suspected lack of efficacy or the possible adverse effects are seldom expressed. The possibility of using deep brain stimulation for psychiatric indications, as well as the experience of some neurosurgeons and the favorable opinion of the rest, might increase the number of operations in our country.

Binge administration of 3,4-methylenedioxymethamphetamine ("ecstasy") impairs the survival of neural precursors in adult rat dentate gyrus.

3,4-Methylenedioxymethamphetamine (MDMA) is a potent stimulant and hallucinogenic drug whose ability to regulate neurogenesis in the adult has not been previously investigated. We used 5'-bromo-2-deoxyuridine (BrdU) and Ki-67 as mitotic markers, and doublecortin (DCX) as a marker of immature neurons, to study proliferation, survival and maturation of adult-generated cells in the dentate gyrus (DG) of the hippocampus following binge administration of MDMA (8 injections of 5 mg/kg at 6 h intervals). The results showed that MDMA treatment did not affect cytogenesis in the DG, but significantly decreased the survival rate of cells incorporated after 2 weeks to the granular layer of the DG by ca. 50%, and of those remaining in the subgranular layer by ca. 30%. Two weeks after exposure to MDMA the length of dendritic arbors and the number of dendritic branches of immature DCX+ neurons were nearly identical to those of control rats, as was the level of colocalization of BrdU with DCX. These results demonstrate that binge MDMA administration does not affect the proliferation rates of progenitor cells in the DG, but has deleterious effects on adult neurogenesis by impairing the short-term survival of vulnerable neural precursors.

Suppression of the cardiac electric field artifact from the heart action evoked potential.

The study of heart action-related brain potentials is strongly disrupted by the presence of an inherent cardiac electric artifact. The hypothesis is presented that most of the electric current coupled to the cardiac field surrounds the skull and flows through the scalp tissue without crossing the cranial cavity. This pseudo two-dimensional conduction model contrasts with the volumetric conduction of the brain electrical activity, and this property is exploited to cancel the cardiac electric artifact. QRS loop vector-cardiographic projections on saggital planes were recorded in 11 healthy subjects in the head and neck areas. Comparative analysis of the projection eccentricities, estimated by the correlation coefficients of the paired data on each area, supported the hypothesis and allowed the handling of the cardiac electric field at the scalp as if enclosed in a two-dimensional wrapped space. This approach permitted the combination of different heart action-related brain potentials recorded at different electrode positions to cancel the cardiac electric artifact. The cancellation method, applied to the subjects' EEG data, yielded a slow cortical potential with a negligible cardiac electric residue and an amplitude of about 1.5-2 microV, with a maximum around 150 ms and a minimum at 400 ms post-R wave.

Quantification of intracranial contribution to rheoencephalography by a numerical model of the head.

OBJECTIVES: Partial contributions of intracranial and extracranial circulation to rheoencephalography (REG) remain uncertain. The main goal of this work is to determine theoretically the capability of REG techniques to reflect intracranial blood flow. METHODS: Head and current injection electrodes were computationally modeled to assess REG sensitivity to brain and scalp conductivity changes. Data obtained were related to tissue perfusions to calculate the partial contribution of cerebral blood perfusion to REG I, REG II and monopolar REG and to assess their amplitudes. RESULTS: When REG I and monopolar REG were used, the theoretical maximum of intracranial contribution was reached with large current injection electrodes, being 8% for REG I and 12% for monopolar REG. However, some specific REG II electrode arrangements showed a nil contribution of the extracranial circulation and a minimum influence of the electrode size. CONCLUSIONS: These results may explain the disagreement on REG origin and suggest a theoretically optimum electrode arrangement.

Anticonvulsant and neurotoxic effects of intracerebroventricular injection of phenytoin, phenobarbital and carbamazepine in an amygdala-kindling model of epilepsy in the rat.

OBJECTIVE: To determine the feasibility of the intracerebroventricular injection of phenytoin (PHT), phenobarbital (PB) and carbamazepine (CBZ) to control seizures in the amygdala kindling model in the rat, and also to determine the associated neurotoxic effects. METHODS: Different doses of PHT (500 and 1250 microl), PB (200, 500 and 1000 microl) and CBZ (200 and 500 microl) were injected intracerebroventricularly into amygdala kindled male Wistar rats. Seizures were induced with a fixed suprathreshold stimulus of 500 microA at times between 15 and 60 min after the injection. Seizure intensity (Racine's scale), latency, seizure duration and afterdischarge duration were measured. Neurotoxicity was tested using ataxia and sedation scales and also using a rotorod. RESULTS: PB was found to be the most powerful anticonvulsant, and both PB and CBZ caused significant reductions in seizure intensity to less than stage 3 with the doses tested. PHT only reduced seizures for the first 15-30 min after application. PB was also the most toxic drug, followed by CBZ and by PHT. Neurotoxicity was acceptable except in the cases of the highest doses during the earliest periods tested. There was no mortality due to the injection of any of the drugs at the doses employed. CONCLUSIONS: The intracerebroventricular route is a feasible way to administer anticonvulsant drugs for seizure control in the kindling model.

Radiosurgery of carotid-cavernous fistulae.

25 cases of carotid-cavernous fistulae (CCF) who underwent radiosurgery with a conventional gamma source from 1977 to 1992 are reported. 22 were low-flow, spontaneous CCFs and 3 were high flow fistulae which had undergone a previous trapping. The total dose delivered was 30 to 40 Gy. 91% to patients with low-flow CCF cured after radiosurgery in a mean time of 7.5 months, presenting improvement in a mean time of 2.3 months. Only one of the high-flow fistulae was cured. Follow-up period ranged between 14 years and 15 months (mean: 50 months). No recurrence was recorded in any case. While intravascular embolotherapy is the treatment of choice for high-flow fistulae, stereotactic radiosurgery may be the elective treatment for low-flow CCF.