ABSTRACT
En 1878 Brocca llamó el gran lóbulo límbico a las áreas corticales que rodeaban en forma de anillo al cuerpo calloso. Esto incluía el giro cingulado , el giro esplénico, el hipocampo y la amígdala del lóbulo temporal (áreas 23, 24, 25, 26, 27, 28, 32 y 34)...
Subject(s)
Cerebral Cortex , Mental Disorders , Neurosurgery , PsychiatryABSTRACT
Resumen: La neurocirugía para tratar los trastornos psiquiátricos tiene sus primeros antecedentes modernos a mediados del siglo XIX con los trabajos de Buckhart, quien resecó parcialmente la corteza frontal de pacientes psiquiátricos. Aunque los resultados fueron alentadores en cuatro de seis casos, la muerte de uno y crisis convulsivas en otros dos frenaron el desarrollo de este procedimiento. En 1936, Egas Moniz y Almeida Lima efectuaron una sección de las fibras frontales en pacientes psiquiátricos con diversos diagnósticos, procedimiento que denominaron lobotomía prefrontal. El éxito de este tratamiento llevó a Moniz a obtener un premio Nobel en 1949. A su vez, esto alentó a Fulton y a Jacobsen a promover este tipo de procedimientos, denominados entonces "psicocirugía", en Estados Unidos. Desafortunadamente, la ausencia de un entendimiento adecuado de la fisiopatología y la sobreindicación de los procedimientos provocó que entre 1935 y 1950 se operaran alrededor de 20,000 pacientes en condiciones cuestionables y con importantes complicaciones. La aparición de los fármacos antipsicóticos y la falta de regulación y entendimiento de la neurocirugía psiquiátrica evitan nuevamente que este tratamiento se realice de manera científica y controlada. Aun así, Spiegel y Wacis iniciaron en 1946 la era de la neurocirugía estereotáctica que reduce el riesgo de complicaciones de la neurocirugía funcional. Cuatro procedimientos fueron aceptados entonces por la OMS para el tratamiento seguro y efectivo de enfermedades psiquiátricas. Estas cirugías incluyen la cingulotomía, la capsulotomía anterior, la tractotomía subcaudada y la leucotomía límbica (combinación de cingulotomía y tractotomía). Por otro lado, los trastornos psiquiátricos que han mostrado mejoría sustancial después de alguno de estos procedimientos neuroquirúrgicos son el trastorno depresivo mayor, el trastorno obsesivo-compulsivo, el trastorno bipolar, algunos trastornos de ansiedad, la adicción a sustancias y los trastornos impulsivos-agresivos. Es importante señalar que los criterios de inclusión a protocolos neuroquirúrgicos asistenciales o de investigación para mejorar los síntomas psiquiátricos han sido bien establecidos, y la selección de pacientes y los grupos neuroquirúrgicos deben ser supervisados por un comité de ética bien acreditado. Actualmente, las indicaciones para proponer como candidato a neurocirugía a un paciente son: Una enfermedad psiquiátrica diagnosticada de acuerdo con los criterios del DSM IV-R; evidencia de refractariedad (mejoría inferior a 50% de los síntomas) con los tratamientos convencionales; ésta debe ser avalada por dos psiquiatras. El padecimiento debe tener una duración de al menos cinco años. Además, un comité ético revisor de los protocolos quirúrgicos y de investigación debe evaluar a cada candidato al procedimiento o protocolo y cerciorarse de que el paciente o las personas responsables de él entiendan los criterios médicos y psiquiátricos para participar en el proceso; el comité supervisa también el proceso de consentimiento. Los procedimientos neuroquirúrgicos sólo podrán ser indicados en pacientes psiquiátricos con capacidad y ellos mismos aprobarán y firmarán un consentimiento informado. Las clínicas de neurocirugía psiquiátrica deberán trabajar estrechamente y contar con los siguientes especialistas: Un equipo de neurocirujanos estereotácticos con experiencia probada en neurocirugía psiquiátrica, neuromodulación, radiocirugía e investigación. Un equipo de psiquiatras con amplia experiencia en condiciones psiquiátricas y de investigación. Preferiblemente, ambos grupos deberán tener experiencia en neurocirugía psiquiátrica o contar con la asesoría de una clínica de neurocirugía psiquiátrica. La neurocirugía psiquiátrica deberá realizarse sólo para restaurar la función normal y aliviar al paciente de su angustia y sufrimiento. Los procedimientos deberán practicarse para mejorar la vida de los pacientes y nunca por motivos políticos, cuestiones legales o propósitos sociales. Finalmente, la neuromodulación ha demostrado ser una técnica útil y segura para el alivio de trastornos psiquiátricos debido a que sus efectos son reversibles y ajustables a cada paciente. Por lo mismo, en la actualidad se ha aplicado con éxito en el tratamiento de la depresión mayor, el trastorno obsesivo compulsivo y la enfermedad de Gilles de la Tourette.
Abstract: Recent background in neurosurgery for psychiatric disorders can be placed in the mid XIXth century. Buckhartd made partial resection of frontal cortex in 6 psychiatric patients, with successful results in 4 of them, but important side effects prevented the development of this scientific approach. In 1936 Egas Moniz and Almeida Lima performed a new neuro-psychiatric technique for treatment of several psychiatric disorders, named prefrontal lobotomy. Results of this treatment won Moniz a Nobel Prize in 1949, and encouraged Freeman and Watts to further develop this kind of surgery in United States of America. Unfortunately, the knowledge about pathophysiology was not sufficient to make a precise indication of surgery in this patients. Between 1935 and 1950, nearly 20,000 surgeries were performed in doubtful conditions, showing important side effects. On the other hand, the emergency of new drugs for the treatment of psychiatric disorders along with the absence of regulation stopped development of "psychosurgery". However, in 1946 Spiegel and Wacis started stereotactic age of neurosurgery, thus reducing risk and complication of this procedures. Nowadays, World Health Organization accepted four neurosurgery procedures for psychiatric disorders: cingulotomy, anterior capsulotomy, subcaudate tractotomy and limbic leucotomy (a combination of cingulotomy and subcaudate tractotomy). Best results for this kind of surgery are shown for affective disorders (major depression disorder, bipolar disorder, anxiety disorders) and obsessive compulsive disorder. Besides, in clinical research protocols the inclusion criteria for neurosurgical procedures in psychiatry have been well defined. Both patients' selection and medical team must be monitored by ethics committee. Currently, the requirements to consider a patient as a candidate for psychiatric neurosurgery are: Clear psychiatric diagnosis in accordance to Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM.IV-TR). Evidence of refractivity (improved of symptoms inferior to 50%) to conventional treatments provided by two different psychiatrists. A minimum of 5 years of evolution in symptoms. The ethics committee must monitor surgical and research protocols in a case by case basis. The Committee will made sure that patient and relatives understand medic and psychiatric inclusion criteria. Neurosurgical procedures will only be indicated when the patient is able to understand and accept any details presented to him or her in a formal Consent Form. Neurosurgery psychiatric clinical teams should be integrated by: Stereotactic neurosurgeons whose have experience in psychiatric neurosurgery, neuromodulation, radiosurgery and clinical issues. A psychiatric team with ample experience in psychiatric conditions and research protocols. In case both teams of specialists are not experienced enough in the field of psychiatric neurosurgery, they must look for technical advice from other neurosurgical psychiatric centers. Psychiatric neurosurgery can only be performed to recover healthy conditions and relief suffering. These interventions must always be performed with the sole objective of improving patients quality of life and they must never be used for political, legal or social purposes. Finally, Neuromodulation has shown to be a useful and safe tool in relief of psychiatric disorders. Neuromodulation's effects are reversible and they can adjusted to patient. Nowadays, Neuromodulation is being used in patients with major depression, obsessive compulsive disorder and Tourette's illness.
ABSTRACT
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Abstract: Composition and quantity of food in-taken varies considerably between one meal and another, or between one day and the following. Non biological factors -such as emotional, social, day time, feasibility in the type of food, and cost- are, among others, factors that in some way affect the degree of energy in-take by food, which generally is not related with daily energy expenditure. These phenomena represent an active process of regulation that is characterized by the balance between signs that stimulate hunger, called orexigenics and those that produce satiation to stop in-take, called anorexigenics, that promotes the stability in the quantity of corporal energy manifested as fat. In this feeding regulatory process there are many molecular signs that participate and regulate the in-take of behaviour food for homeostasis. There are two hypothalamic centers related with the food in-take control: the hunger centre in the lateral hypothalamus and the satiation centre in the ventromedial nucleus. In this control many impulses participate, regulated by substances called neurotransmitters, such as: neuropeptide Y, galanine, orexines for the hunger centre and nor epinephrine, serotonin, and dopamine for the satiation centre. Insulin reaches the brain through circulation and acts reducing the contribution of energy, it was the first hormonal sign that was implicated in weight control by CNS. The second identified hormone, secreted by the adiposity, was leptin. Both hormones circulate in levels proportional to the corporal fat and get to the CNS in proportion to its plasmatic concentrations. Receptors as leptin and insulin are expressed by brain neurons involved in the contribution of energy, and the administration of any of both peptides directly to the brain, reduce the in-take of food. The lack of any of these hormones produces the opposite. Leptin has a more important role than insulin in the control of the energetic homeostasis in the CNS. For example, the lack of leptin causes severe obesity with hyperfagia that persists regardless the levels of elevated insulin. In contrast, obesity isn't induced by the lack of insulin. Insulin has a critic role to promote the storage of fat and the synthesis of leptin through the fat cellule. The neuropeptide Y, produced in the arcuate nucleus of the hypothalamus has an anabolic effect. The gene of expression and secretion of this peptide in the hypothalamus increases during depletion, in the storage of corporal fat and/or when the signs of leptin/insulin are decreased in the brain. Leptin inhibits the gene of expression of the neuropeptide Y in the arcuate nucleus and the genetic "knockout" of the NPY reduces hyperfagia and obesity in mice ob/ob, indicating that the total response to the lack of leptin requires the signs of the NPY. Other substances like the Agouti protein (AGRP), the orexines (hypocretines A and B) and the concentrations of the melancortin hormone have been added to the molecule candidate list with anabolic effects. Also in the adjoining neurons of the arcuate nucleus, are originated anorexigenic peptides like alfa-MSH (a derivated of the pro-opiomelancortin, POMC) and CART (transcript protein related with cocaine and amphetamine). Both types of neurons (NPY/AGRP and POMC/CART) coexpress the leptin receptors. In those situations in which the levels of leptin or insulin are low, the NPY/AGRP neurons activate and the POMC/CART are inhibited. This suggests that the main site of adiposity signs transformation is a neuronal response in the arched nucleus. The link between the lateral hypothalamus and the elevated centers of the brain that regulate hunger and satiation is a very important aspect of the regulation system. There have been typified two types of neuropeptides linked to neurons, that appear to be exclusively of the lateral hypothalamus area: the concentrated melanin hormone (MCH) and the orexines. At the lateral zone, there have been specified two types of hypothalamic neuropeptides, the orexines A and B, also known as hypocretines 1 and 2, which are cellular bodies of the hypothalamus, especially at the lateral hypothalamus and the perifornical area, which stimulate the appetite in an independent way to other neuropeptides known. On the other hand, the orexines A and B derive (by proteolysis) of a common precursor, and are capable of activating their two respective receptors that work in conjunction with proteins G. The central administration of orexines stimulates the in-take and production of orexines' increase with fasting. These neuropeptides match with the hypocretines described by other authors, with expression in late ral hypothalamus, arched nucleus, septal nucleus and forebrain. Monoaminergic neurotransmitters. Noradrenalin Noradrenalin is synthesized in different areas of the brain such as the dorsal nucleus of the vague and the locus coeruleus.Noradrenalin shares the same place with NPY and the injection of both inside the preventricular nucleus increase the in-take of food. The repeated injection can result in weight increase; leptin can inhibit noradrenalin secretion. Dopamine Critic dependence of the in-take of food in the CNS is given by the dopamine sign, which is implicated in the voluntary lack of the food in-take. Motor alterations associated with the lack of dopamine affect also the alimentary behavior. The dopamine effect over the alimentary behavior varies depending of the studyied area. For example the routes of dopamine in the mesolimbic area contribute to the reward of the in-take of savory food. SerotoninThe 5HT2c receptor of serotonin is implicated in the decrease of the in-take of food and the weight increase, due to its effect in the impulse of the satiation centre. To maintain the homeostasis of normal energy it is necessary that the serotonin sign be intact. New alternative hypothesis. On one hand, the knowledge of regulation of the appetite-satiety neuroendocrine cycle, and on the other, the new techniques of neuromodulation through stereotaxic surgery, allow to offer an extraordinarily interesting field of research in certain patients with feeding disorders of difficult control and with an increase in the mortality risk. The alternative of controlling specific centers of hunger/satiation regulation, is still a hypothesis, though there are some data that allow us to assume that it could be feasible and we will mention them after. Current experience. Stereotaxic (Latin: stereo, three-dimensional; taxis, positioning) is a modern technique of neurosurgery that allows the localization and precise access to intra-cerebral structures, through a small orifice in the skull. If we have identified the places that regulate the intake of food or satiety, it is feasible that through this technique we can stimulate or inhibit this function and offer the patient an alternative that in theory could be feasible. Some of its possible advantages will be that we are talking about a minimum invasive surgery, generally performed using local anesthesia; patients need a minimum hospitalization stay and surgical risks are minimized. This allows us to predict in the majority of the patients a satisfactory evolution of weight decrease. The current experience of stereotaxic used in eating disorders is null; everything about it is hypothetic. However, the use of this proceeding for other accepted indications where there is previous experience, has allowed us to obtain interesting data of the evolution of these patients that shows indirectly, that the procedure has influenced in the corporal weight. We present these indirect results, which motivate us to continue considering its possible use in patients that show the approved profile according to an ethic committee properly authorized. In depression or bipolar disorder cases, the use of the stereotaxic surgery applying electrodes in the bottom pedunculo thalamic region (ITP), independently that they show an improve in their basal alteration, the patients show a weight increase, inferring a relationship of this area and the one of the hypothalamus for the appetite/satiation control, situation that hypothetically could benefit patients with anorexia nervosa or bulimia. In the cases with Parkinson Disease, the stereotaxic procedure has been made in the pre-lemniscal (RAPRL) or the subtalamic region (STN) in a unilateral or bilateral way, and although the response hasn't been uniform, the weight changes showed a decrease, making this a possible alternative to be used in some patients with morbid obesity according to the inclusion criteria. Final comments. The expectative of stereotaxic surgery in handling patients with difficult to control feeding disorders or with high risk of morbid-mortality, is shown as an hypothesis, that should consider the specific rules of good clinical practices and adjust to the rules of an approved ethics committee, for these procedures.
ABSTRACT
Este trabajo estudia los efectos del tratamiento médico y quirúrgico sobre el curso natural de la enfermedad de Parkinson. Tres grupos de pacientes fueron estudiados: I. Pacientes tratados con levodopa/carbidopa y anticolinérgicos (n = 10). II. Pacientes tratados con talamotomía (n = 9). III. Pacientes con tratamiento médico más trasplante autólogo de médula adrenal al núcleo caudado (n = 8). Fueron evaluados antes de iniciar el tratamiento médico o de efectuar la cirugía, al mes, a los seis meses y al año. Fueron usadas las escalas clínicas: New York Parkinson's Disease Scale, Unified Parkinson's Disease Scale, Schwab and England y Hoehn and Yarth Scale. Se evaluó por separado temblor, rigidez, bradicinesia y deterioro mental. Se uso un análisis de varianza tipo Friedman. Grupo I. No hubo mejoría significativa y sí un deterioro mental significativo al año. Grupo II. Hubo mejoría significativa del temblor y la rigidez, sin embargo el deterioro mental al año determinó un empeoramiento de la escala global. Grupo III. No hubo mejoría significativa, pero el deterioro al año fue menos pronunciado que para los otros grupos