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Fornicotomy has been used to treat intractable temporal lobe epilepsy with mixed success historically; however, modern advances in stereotactic, neurosurgical, and imaging techniques offer new opportunities to target the fornix with greater precision and safety. In this review, we discuss the historical uses and quantify the outcomes of fornicotomy for the treatment of temporal lobe epilepsy, highlight the potential mechanisms of benefit, and address what is known about the side effects of the procedure. We find that fornicotomy, with or without anterior commissurotomy, resulted in 61% (83/136) of patients having some seizure control benefit. We discuss the potential operative approaches for targeting the fornix, including laser ablation and the use of focused ultrasound ablation. More work is needed to address the true efficacy of fornicotomy in the modern surgical setting. This review is intended to serve as a framework for developing this approach.

INTRODUCTION: Rett syndrome is a neurodevelopmental genetic disorder, characterized by developmental delay, hand stereotypies, abnormal gait, and acquired microcephaly. Epilepsy is very common in Rett syndrome and can be medically intractable. It remains uncertain if a patient with epileptic drop attacks associated with this genetic disease can benefit from corpus callosotomy. CASE REPORT: We report an 8-year-old girl with Rett syndrome and medically intractable epileptic drop attacks who underwent endoscopic total corpus callosotomy without any complications that led to the successful elimination of her seizures. CONCLUSION: Total corpus callosotomy is a feasible treatment option for medically intractable epileptic drop attacks in Rett syndrome and should not be considered as a contraindication in this condition. This is the first reported case of corpus callosotomy in Rett syndrome.

Herein, we report the case of a 35-year-old female with a trapped right lung secondary to catamenial haemothorax. Following surgical decortication, re-expansion of the lung was not observed until postoperative day 81. This delay represents a heretofore unencountered complication that should be considered in the surgical management of catamenial haemothorax due to thoracic endometriosis syndrome.

The balance between glutamate (cortex and thalamus) and dopamine (substantia nigra) inputs on striatal neurons is of vital importance. Dopamine deficiency, which breaks this balance and leads to the domination of cortical glutamatergic inputs, plays an important role in Parkinson's disease (PD). However, the exact impact on striatal neurons has not been fully clarified. Thus, the present study aimed to characterize the influence of corticostriatal glutamatergic inputs on striatal neurons after decortication due to dopamine depletion in rats. 6‑Hydroxydopamine was injected into the right medial forebrain bundle to induce dopamine depletion, and/or ibotenic acid into the primary motor cortex to induce decortication. Subsequently, the grip strength test and Morris water maze task indicated that decortication significantly shortened the hang time and the latency that had been increased in the rats subjected to dopamine depletion. Golgi staining and electron microscopy analysis showed that the total dendritic length and dendritic spine density of the striatal neurons were decreased in the dopamine‑depleted rats, whereas decortication alleviated this damage. Immunohistochemistry analysis demonstrated that decortication decreased the number of caspase‑3‑positive neurons in the dopamine‑depleted rats. Moreover, reverse transcription‑quantitative PCR and western blot analyses showed that decortication offset the upregulation of caspase‑3 at both the protein and mRNA levels in the dopamine‑depleted rats. In conclusion, the present study demonstrated that a relative excess of cortical glutamate inputs had a substantial impact on the pathological processes of striatal neuron lesions in PD.

One of the potential disadvantages of conventional pleurectomy/decortication for malignant pleural mesothelioma is the need for opening the pleural sac, which might worsen survival. In this study, we have introduced non-incisional pleurectomy/decortication as an alternative technique that does not require the opening of the pleural sac.

Previously, studying the development, especially of corticospinal neurons, it was concluded that the main compensatory mechanism after unilateral brain injury in rat at the neonatal stage was due in part to non-lesioned ipsilateral corticospinal neurons that escaped selection by axonal elimination or neuronal apoptosis. However, previous results suggesting compensatory mechanism in neonate brain were not correlated with high functional recovery. Therefore, what is the difference among neonate and adult in the context of functional recovery and potential mechanism(s) therein? Here, we utilized a brain unilateral decortication mouse model and compared motor functional recovery mechanism post-neonatal brain hemisuction (NBH) with adult brain hemisuction (ABH). Three analyses were performed: (1) Quantitative behavioral analysis of forelimb movements using ladder walking test, (2) neuroanatomical retrograde tracing analysis of unlesioned side corticospinal neurons, and (3) differential global gene expressions profiling in unlesioned-side neocortex (rostral from bregma) in NBH and ABH on a 8 × 60 K mouse whole genome Agilent DNA chip. Behavioral data confirmed higher recovery ability in NBH over ABH is related to non-lesional frontal neocortex including rostral caudal forelimb area. A first inventory of differentially expressed genes genome-wide in the NBH and ABH mouse model is provided as a resource for the scientific community.

Background An extensive frontal resection is a frequently performed neurosurgical procedure, especially for treating brain tumor and refractory epilepsy. However, there is a paucity of reports available regarding its surgical anatomy and technique. Objectives We sought to present the anatomic landmarks and surgical technique of the frontal lobe decortication (FLD) in epilepsy. The goals were to maximize the gray matter removal, spare primary and supplementary motor areas, and preserve the frontal horn. Material and Methods The anatomic study was based on dissections performed in 15 formalin-fixed adult cadaveric heads. The clinical experience with 15 patients is summarized. Result FLD consists of 5 steps: 1) coagulation and section of arterial branches of lateral surface; 2) paramedian subpial resection 3 cm ahead of the precentral sulcus to reach the genu of corpus callosum; 3) resection of gray matter of lateral surface, preserving the frontal horn; 4) removal of gray matter of basal surface preserving olfactory tract; 5) removal of gray matter of the medial surface under the rostrum of corpus callosum. The frontal horn was preserved in all 15 patients; 12 patients (80%) had no complications; 2 patients presented temporary hemiparesis; and 1 Rasmussen syndrome patient developed postoperative fever. The best seizure control was in cases with focal magnetic resonance imaging abnormalities limited to the frontal lobe. Conclusion FLD is an anatomy-based surgical technique for extensive frontal lobe resection. It presents reliable anatomic landmarks, selective gray matter removal, preservation of frontal horn, and low complication rate in our series. It can be an alternative option to the classical frontal lobectomy.

The current decerebration procedures discard the role of the thalamus in the motor control and decortication only rules out the brain cortex part, leaving a gap between the brain cortex and the subthalamic motor regions. In here we define a new preparation denominated Brain Cortex-Ablated Cat (BCAC), in which the frontal and parietal brain cortices as well as the central white matter beneath them were removed, this decerebration process may be considered as suprathalamic, since the thalamus remained intact. To characterize this preparation cat hindlimb electromyograms (EMG), kinematics and cutaneous reflexes (CR) produced by electrical stimulation of sural (SU) or saphenous (SAPH) nerves were analyzed during locomotion in intact and in BCAC. In cortex-ablated cats compared to intact cats, the hindlimb EMG amplitude was increased in the flexors, whereas in most extensors the amplitude was decreased. Bifunctional muscle EMGs presented complex and speed-dependent amplitude changes. In intact cats CR produced an inhibition of extensors, as well as excitation and inhibition of flexors, and a complex pattern of withdrawal responses in bifunctional muscles. The same stimuli applied to BCAC produced no detectable responses, but in some cats cutaneous reflexes produced by electrical stimulation of saphenous nerve reappeared when the locomotion speed increased. In BCAC, EMG and kinematic changes, as well as the absence of CR, imply that for this cat preparation there is a partial compensation due to the subcortical locomotor apparatus generating close to normal locomotion.

The retinal ganglion cells were counted in a rhesus monkey from which the striate cortex had been removed 8 years earlier, and the results compared with those obtained previously with the eyes of normal monkeys. About 80% of the ganglion cells within 10 degrees of the fovea were missing. Peripherally their density was unaffected. The ganglion cell layer of the entire retina resembled the peripheral retina of a normal monkey, and this result helps to explain the remarkable nature of the animal's vision.

Following brain damage, especially in juvenile animals, large-scale reorganization is known to occur in the remaining brain structures to compensate for functional deficits. In rats with neonatal hemidecortication, corticospinal fibers originating from the undamaged side of the sensorimotor cortex issue collateral sprouts to the ipsilateral spinal gray matter that mediate cortical excitation to ipsilateral forelimb motoneurons and compensate for the deficit in forelimb movements. The present study was designed to investigate the origins of the ipsilateral corticospinal projection in neonatally hemidecorticated rats. Corticospinal neurons (CSNs) were labeled in adults by injecting retrograde neural tracers, cholera toxin subunit B with different fluorescent probes, into either side of the cervical spinal gray matter. In the undamaged cortex, double-labeled neurons were rarely found. CSNs with contralateral projections (contra-CSNs) and those with ipsilateral projections (ipsi-CSNs) were distributed both in the rostral forelimb motor area (RFA) and the caudal forelimb motor area (CFA). However, there was a difference in the distributions of the ipsi-CSNs between the two forelimb areas. Whereas the distribution of the ipsi-CSNs largely overlapped with that of the contra-CSNs in the RFA, the ipsi-CSNs tended to be segregated from the contra-CSNs in the CFA. The results suggested that the RFA and the CFA contribute to the compensatory process in different ways.

To examine the compensatory mechanisms in rats that underwent left decortication at postnatal day 7 (P7), we injected the retrograde tracers fluorescein isothiocyanate-cholera toxin B subunit (FITC-CTB) and Fast Blue (FB) into the right and left upper cervical spinal cord, respectively, at postoperative weeks 2, 3, 4, and 5 and counted the number of retrogradely labeled corticospinal neurons in the right cerebral cortex compared with that in normally developed rats. Significantly more ipsilaterally projecting neurons were labeled with FITC-CTB in the decorticated rats compared with normal rats at all time points examined. The number of labeled neurons was similar to that at P7 in normal rats. There were also some FITC-CTB and FB double-labeled neurons in both decorticated and normal rats. The number of double-labeled neurons in the decorticated rats increased each week and was significantly greater than that in normal rats at postoperative weeks 4 and 5. The present results suggest that the elimination of ipsilaterally projecting axons observed in normal rats was prevented in the decorticated rats, so that the cerebral cortex neurons on the unlesioned side projected corticospinal tracts to the ipsilateral spinal cord. Furthermore, the collaterals of the corticospinal tracts originating from the cerebral cortex on the unlesioned side also project to the ipsilateral spinal cord. These compensatory mechanisms might underlie the acquisition of motor function in these animals.

Neonatally hemidecorticated rats show fairly normal reaching and grasping behaviors of the forelimb contralateral to the lesion at the adult stage. Previous experiments using an anterograde tracer showed that the corticospinal fibers originating from the sensorimotor cortex of the intact side projected aberrant collaterals to the spinal gray matter on the ipsilateral side. The present study used electrophysiological methods to investigate whether the aberrant projections of the corticospinal tract mediated the pyramidal excitation to the ipsilateral forelimb motoneurons and, if so, which pathways mediate the effect in the hemidecorticated rats. Electrical stimulation to the intact medullary pyramid elicited bilateral negative field potentials in the dorsal horn of the spinal cord. In intracellular recordings of forelimb motoneurons, oligosynaptic pyramidal excitation was detected on both sides of the spinal cord in the hemidecorticated rats, whereas pyramidal excitation of motoneurons on the side ipsilateral to the stimulation was much smaller in normal rats. By lesioning the dorsal funiculus at the upper cervical level, we clarified that the excitation was transmitted to the ipsilateral motoneurons by at least two pathways: one via the corticospinal tract and spinal interneurons and the other via the cortico-reticulo-spinal pathways. These results suggested that in the neonatally hemidecorticated rats, the forelimb movements on the side contralateral to the lesion were modulated by motor commands through the indirect ipsilateral descending pathways from the sensorimotor cortex of the intact side either via the spinal interneurons or reticulospinal neurons.

A best evidence topic in thoracic surgery was written according to a structured protocol. The question addressed was whether video-assisted thoracoscopic surgical decortication (VATSD) might be superior to open decortication (OD) (or chest tube drainage) for the management of adults with primary empyema? Altogether 68 papers were found using the reported search, of which 14 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. We conclude that VATSD has superior outcomes for the treatment of persistent pleural collections in terms of postoperative morbidity, complications and length of hospital stay, and gives equivalent resolution when compared with OD. One study comparing VATSD and chest tube drainage of fibrinopurulent empyema found video-assisted thoracoscopic surgery (VATS) had higher treatment success (91% vs. 44%; P0.05), lower chest tube duration (5.8+/-1.1 vs. 9.8+/-1.3 days; P=0.03), and lower number of total hospital days (8.7+/-0.9 vs. 12.8+/-1.1 days; P=0.009). Eight studies comparing early and late empyema report conversion rates to OD of 0-3.5% in early, 7.1-46% in late stage and significant reductions in length of stay with VATSD compared with OD both postoperatively (5 vs. 8 days; P=0.001) and in total stay (15 vs. 21; P=0.03). Additionally VATS resulted in reduced postoperative pain (P0.0001) and complications including atelectasis (P=0.006), prolonged air-leak (P=0.0003), sepsis (P=0.03) and 30-day mortality (P=0.02). Five studies considered only chronic persistent empyema of which two directly compared VATSD to tube thoracostomy (TT). VATS resolved 88% of cases and had mortality rates of 1.3% compared with 62% and 11%, respectively, for TT. Moreover, conversion to OD was 10.5-17.1% with VATS and 18-37% with TT (P0.05). In agreement with mixed stage empyema, hospital stay was reduced both postoperatively (8.3 vs. 12.8 days; P0.05) and in total (14+/-1 vs. 17+/-1 days; P0.05), and when compared with OD (one study), pain (P0.0001), postoperative air-leak (P=0.004), hospital stay (P=0.020) and time to return to work (P0.0001) were all reduced with VATS. Additionally, re-operation (4.8% vs. 1%; P=0.09) and mortality (4/123% vs. 0%) were lower in VATS vs. OD.

The orbitofrontal cortex (OFC) has been implicated in reinforcement-guided decision making, error monitoring, and the reversal of behavior in response to changing circumstances. The anterior cingulate cortex sulcus (ACCS), however, has also been implicated in similar aspects of behavior. Dissociating the unique functions of these areas would improve our understanding of the decision-making process. The effect of selective OFC lesions on how monkeys used the history of reinforcement to guide choices of either particular actions or particular stimuli was studied and compared with the effects of ACCSlesions. Both lesions disrupted decision making, but their effects were differentially modulated by the dependence on action– or stimulus–value contingencies. OFC lesions caused a deficit in stimulus but not action selection, whereas ACCSlesions had the opposite effect, disrupting action but not stimulus selection. Furthermore, OFC lesions that have previously been found to impair decision making when deterministic stimulus–reward contingencies are switched were found to cause a more general learning impairment in more naturalistic situations in which reward was stochastic. Both OFC and ACCSare essential for reinforcement-guided decision making rather than just error monitoring or behavioral reversal. The OFC and ACCSare both, however, more concerned with learning and making decisions, but their roles in selecting between stimulus and action values are distinct.

In the brain after infarction or trauma, the tissue eventually becomes pannecrotic and forms a cavity. In such situations, a scaffold is necessary for the implanted or migrated cells to produce new tissue. In this present study, therefore, we attempted to restore brain tissue using a novel biomaterial, polydimethylsiloxane-tetraethoxysilane (PDMS-TEOS) hybrid with or without vascular endothelial growth factor (VEGF), which is crucial for new vessel formation. When PDMS-TEOS scaffold was implanted into the artificial brain defect, it remained at the implanted site and kept the integrity of the brain shape. At 30 days after the implantation, the marginal territory of PDMS-TEOS scaffold became occupied by newly formed tissue. Immunohistochemical analysis revealed that the new tissue was constituted by astrocytes and endothelial cells. Addition of VEGF increased the newly produced tissue volume, and the immunohistochemical analysis showed that the numbers of astrocytes and endothelial cells were increased. Double staining with proliferation maker Ki67 demonstrated that VEGF significantly increased newly formed astrocytes and endothelial cells, indicating that addition of VEGF accelerated tissue restoration and angiogenesis. These findings show that implantation of PDMS-TEOS scaffold with VEGF might be effective for treating old brain infarction or trauma.

We describe a new test of vibrissae-elicited forelimb placing ability that allows testing of sensorimotor integration across the midline. Rats were given unilateral brain lesions using one of three methods: (1) middle cerebral artery occlusion (MCAo) causing significant damage to the cortex and striatum, (2) aspiration lesions to remove tissue from the sensorimotor cortex, and (3) infusions of the catecholamine neurotoxin 6-hydroxydopamine (6-OHDA) into the medial forebrain bundle, producing a parkinsonian syndrome. Application of the new test to these animals revealed that with some lesion types, the ability of vibrissae on the unimpaired side of the body to trigger placing in the functionally impaired forelimb recovers before vibrissae on the impaired side can elicit placing. This occurs despite the lack of any apparent vibrissae sensory deficit, since the contralesional vibrissae maintained the ability to trigger placing in the unimpaired forelimb in all lesions studied. Chronically, MCAo-lesioned rats do not place the impaired forelimb upon stimulation of the impaired-side vibrissae, but do place if the vibrissae on the good side are stimulated (i.e., when the placing is triggered "across the midline"). This is in contrast to 6-OHDA-lesioned rats which, consistent with parkinsonian akinesia, cannot place the impaired limb regardless of sensory trigger. Also, differences in the pattern of recovery between MCAo- and aspiration-lesioned rats suggest a possible anatomical substrate for cross-midline placing ability and its recovery. Unlike other tests, cross-midline placing methods can readily distinguish between severe stroke and severe parkinsonism in rats.

Cross-correlation functions were used to study the time delay (a measure of synchronization) in the appearance of epileptic discharges in distant areas of the cortex in the intact cortex and in neuronally isolated cortical strips in Wistar rats. Experiments were performed at different stages of axon sprouting 30 and 90 days after isolation of cortical areas and in intact cortex. Significant increases in the number of synapses in layer V of isolated cortical strips at 30 days correlated with significant decreases in the time delay, while decreases in the number of synapses at 90 days correlated with a significant increase in the time delay. This is evidence that newly formed synapses increase the extent of synchronization and thus affect epileptogenesis. The data obtained here suggest that large pyramidal cells in layer V of the rat neocortex form a neural network in pathological conditions, this supporting intracortical synchronization of epileptic discharges.

The hippocampus and the amygdala are involved in avoidance learning in mammals. The medial and lateral pallia of actinopterygian fish have been proposed as homologous to the mammalian pallial amygdala and hippocampus, respectively, on the basis of neuroanatomical findings. This work was aimed at studying the effects of ablation of the medial telencephalic pallia (MP) and lateral telencephalic pallia (LP) in goldfish on the retention of a conditioned avoidance response previously acquired in two experimental conditions. In the first experiment, fish were trained in nontrace avoidance conditioning. In the second experiment, fish were trained in trace avoidance conditioning in which temporal cues were crucial for the learning process. An MP lesion affected the retention of the avoidance response in both procedures; in contrast, an LP lesion impaired the retention only in the trace-conditioning procedure. These data support the presence of two different systems of memory in fish, based on discrete telencephalic areas: the MP, involved in an emotional memory system; and the LP, involved in a spatial, relational, or temporal memory system. Moreover, these differential effects were similar to those produced by amygdalar and hippocampal lesions in mammals. We conclude that these specialized systems of memory could have appeared early during phylogenesis and could have been conserved throughout vertebrate evolution. Ministerio de Ciencia y Tecnología BF-I2001-3178 Ministerio de Ciencia y Tecnología I2000-0315 Ministerio de Ciencia y Tecnología I2003-0029 Ministerio de Ciencia y Tecnología PB-96-1334 Junta de Andalucía CVI-242

This experiment tested the effect of cortical spreading depression on the sympathetic and thermogenic effects induced by orexin A. The firing rates of the sympathetic nerves to interscapular brown adipose tissue (IBAT), along with IBAT and colonic temperatures and heart rate were monitored in urethane-anesthetized male Sprague-Dawley rats before and 5 h after an injection of orexin A (1.5 nmol) into the lateral cerebral ventricle. The same variables were monitored in rats with cortical spreading depression, induced by an application of cotton pellets soaked with 2 M KCl to the frontal cortex. The results show that orexin A increases the sympathetic firing rate, IBAT and colonic temperatures and heart rate. The increases in firing rate, IBAT and colonic temperatures are blocked by cortical spreading depression, while the increase in heart rate is not affected by cortical spreading depression. These findings suggest that the cerebral cortex is involved in the control of the orexin A-induced hyperthermia. Furthermore, we suggested the name "hyperthermine A," as additional denomination of "orexin A." (C) 2003 IBRO. Published by Elsevier Ltd. All rights reserved.