Neuromodulation of the posterolateral hypothalamus for the treatment of chronic refractory cluster headache: Experience in five patients with a modified anatomical target.

INTRODUCTION: Deep brain stimulation (DBS) of the posterior hypothalamus has been found to be effective in the treatment of refractory chronic cluster headache (CCH). METHODS: We report the long-term outcomes of five patients with refractory CCH on whom stimulation of a modified target of approximately 3 mm in radius, which included the posterolateral hypothalamus, the fasciculus mammillotegmentalis, the fasciculus mammillothalamicus and the fasciculus medialis telencephali, was performed. The stereotaxic coordinates were 4 mm from the third ventricle wall, 2 mm from behind the mid-intercommissural point and 5 mm from under the intercommissural line. RESULTS: All patients became pain-free for 1-2 weeks after the procedure, but then needed an average of 54 days to optimize stimulation parameters. After a mean follow-up of 33 months, two remain pain-free, two have an excellent response (>90% decrease in attack frequency) and in one the attacks have been reduced by half. There were no serious adverse events. Permanent myosis and euphoria/well-being feeling were seen in three patients. Other adverse events, such as diplopia, dizziness, global headache of cervical dystonia, were seen transiently related to an increase in stimulation parameters. Attacks reappeared transiently in two patients as a result of cable rupture and when the stimulator was disconnected. CONCLUSIONS: Our results supports the efficacy of DBS in very refractory CCH with a slightly modified hypothalamic target conceived to avoid the lateral ventricle wall so as to extend the stimulated brain area and to decrease the morbidity of potential haemorrhagic complications.

Complications in subthalamic nucleus stimulation surgery for treatment of Parkinson's disease. Review of 272 procedures.

BACKGROUND: Deep brain stimulation (DBS) is a surgical technique used to alleviate symptoms in patients with advanced Parkinson's disease (PD). It is a reversible procedure and its effect is based on electrical modulation of the nervous system and has considerable advantages in morbidity-mortality when compared to lesion techniques such as thalamotomy and/or pallidotomy. The objective was to evaluate the adverse events during the surgical placement of leads in the subthalamic nucleus for the treatment of Parkinson's disease. METHODS: A retrospective data collection was made in a total of 130 patients in whom we performed 272 procedures for the implant of leads in the subthalamic nucleus between May 1998 and December 2005. All the patients were operated by the same surgeon, in the same institution and with the same surgical methodology. The complications under evaluation were: aborted procedure, misplaced leads, intracranial haemorrhage, seizures, hardware complications and other complications. RESULTS: 130 patients were treated (62 women, 68 men; average age 62 (36-74) years). The average duration of disease from the time of diagnosis to operation was 15.3 years (4-28 years) and the mean follow-up was of 37 months (3-93 months). One hundred and twenty four patients were implanted bilaterally and 6 unilaterally. 62% did not present any complications, 30% had one complication, and 8% more than one complication. Aborted procedures amounted to 5.14% of all procedures, misplaced leads 2.2%, intracranial haemorrhage 3.3%, seizures 4.7%, hardware complications 1.8% and other complications 5.1%. CONCLUSION: Deep brain stimulation surgery is an effective and safe method to treat Parkinson's disease with a low incidence of permanent adverse events.

[An automatic system for anatomophysiological correlation in three planes simultaneously during functional neurosurgery]. / Sistema automático para la correlación anatomofisiológica en tres planos simultáneos durante la neurocirugía funcional.

INTRODUCTION: The Neurosurgical Deep Recording System (NDRS) using a personal computer takes the place of complex electronic equipment for recording and processing deep cerebral electrical activity, as a guide in stereotaxic functional neurosurgery. It also permits increased possibilities of presenting information in direct graphic form with automatic management and sufficient flexibility to implement different analyses. OBJECTIVE: This paper describes the possibilities of automatic simultaneous graphic representation in three almost orthogonal planes, available with the new 5.1 version of NDRS so as to facilitate the analysis of anatomophysiological correlation in the localization of deep structures of the brain during minimal access surgery. MATERIAL AND METHODS: This new version can automatically show the spatial behaviour of signals registered throughout the path of the electrode inside the brain, superimposed simultaneously on sagittal, coronal and axial sections of an anatomical atlas of the brain, after adjusting the scale automatically according to the dimensions of the brain of each individual patient. This may also be shown in a tridimensional representation of the different planes themselves intercepting. RESULTS: The NDRS system has been successfully used in Spain and Cuba in over 300 functional neurosurgery operations. The new version further facilitates analysis of spatial anatomophysiological correlation for the localization of brain structures. CONCLUSION: This system has contributed to increase the precision and safety in selecting surgical targets in the control of Parkinson s disease and other disorders of movement.

Sistema automático para la correlación anatomofisiológica en tres planos simultáneos durante la neurocirugía funcional / An automatic system for anatomophysiological correlation in three planes simultaneously during functional neurosurgery

Introducción. El sistema de programas NDRS (Neurosurgical Deep Recording System) sustituye con un ordenador personal el complejo equipamiento electrónico para el registro y procesamiento de la actividad eléctrica cerebral profunda, como guía de la neurocirugía funcional estereotáxica; asimismo, permite mayores posibilidades de representación de la información de forma gráfica directa, su manejo automático y la flexibilidad suficiente para implementar diferentes análisis. Objetivo. Este trabajo describe las posibilidades automáticas de representación gráfica simultánea en tres planos casi ortogonales, ofrecidas por la nueva versión 5.1 del NDRS, para facilitar los análisis de correlación anatomofisiológica en la localización de estructuras cerebrales profundas durante esta cirugía de mínimo acceso. Material y métodos. Esta nueva versión puede mostrar automáticamente el comportamiento espacial de la amplitud de las señales registradas a lo largo del trayecto del electrodo dentro del cerebro, superpuesta simultáneamente sobre los correspondientes cortes sagital, coronal y axial de un atlas anatómico cerebral, tras su escalamiento automático de acuerdo con las dimensiones del cerebro de cada paciente. Ello también puede mostrarse en una representación tridimensional de los diferentes planos interceptados entre sí. Resultados. El sistema NDRS se ha utilizado con éxito en España y Cuba en más de 300 intervenciones neuroquirúrgicas funcionales. Esta nueva versión facilita aún más los análisis de correlación espacial anatomofisiológica para localizar las estructuras cerebrales. Conclusión. El sistema ha contribuido a incrementar la exactitud y seguridad en la selección de los blancos quirúrgicos para el control de diferentes síntomas de la enfermedad de Parkinson y otros trastornos del movimiento (AU)

[Applied neurophysiology in the deep brain stimulation treatment of multiple sclerosis tremor]. / Neurofisiología aplicada en el tratamiento con estimulación cerebral profunda del temblor severo de la esclerosis múltiple.

INTRODUCTION: Many patients with multiple sclerosis (MS) develop tremors that may involve one or both lower and/or upper extremities, head and/or voice. In the last few years, chronic high frequency deep brain stimulation of the ventral intermedious (Vim) thalamic nucleus (Vim-DBS, deep brain stimulation) seems to be gradually replacing Vim-thalamotomy in surgical treatment of tremor. The thalamotomy is a destructive procedure of the whole neural components, whereas Vim-DBS has shown to be a selective neurophysiological procedure to block a specific group of neural components, in particular large, fast and low threshold ones. MS is a disease of uncertain etiology characterized by demyelinating plaques in central nervous system. The neurophysiological intraoperative targeting applied to this pathology identifies demyelinated plaques and the functional state of Vim, reduces pitfalls and increases accuracy. Methods included spontaneous and induced multiunit activity recording, semimicroelectrode and tetraelectrode thalamic evoked potentials recording and micro/macro stimulation techniques.

Neurofisiología aplicada en el tratamiento con estimulación cerebralprofunda del temblor severo de la esclerosis múltiple / applied neurophysiology the deep brain stimulation treatment of multiple sclerosis tremor

Introducción. Los pacientes con esclerosis múltiple (EM) desarrollan temblores que pueden afectar a una o ambas extremidades inferiores y/o superiores, a la extremidad cefálica y/o a la voz.Recientemente, la estimulación cerebral profunda del núcleo ventral intermedio (Vim) del tálamo (clasificación de Hassler), utilizando estímulos eléctricos a alta frecuencia (Vim-DBS, del inglés deep brain stimulation), está reemplazando gradualmente a la talamotomía de dicho núcleo talámico. Desarrollo. Mientras que la talamotomía es un procedimiento destructivo que aniquila la totalidad de componentes neurales de un área determinada, la Vim-DBS es un método neurofisiológico selectivo que bloquea los diferentes componentes neuronales en función de la intensidad, duración y frecuencia de los pulsos eléctricos aplicados, en particular bloqueando los componentes con bajo umbral. La EM es una enfermedad caracterizada por producir placas de desmielinización en el sistema nervioso central. En este sentido, la monitorización neurofisiológica para localizar la diana (Vim) permite reducir dificultades, identificar placas, elucidar sobre el estado funcional del Vim e incrementar la precisión. Los métodos utilizados en tal monitorización son el registro espontáneo e inducido de la actividad multiunitaria neuronal, potenciales evocados talámicos registrados con semimicroelectrodo y tetraelectrodo, y las técnicas de micro y macroestimulación con dichos electrodos (AU)

Sistema automático para la correlación anatomofisiológica en tres planos simultáneos durante la neurocirugía funcional / An automatic system for anatomophysiological correlation in three planes simultaneously during functional neurosurgery

Introducción. El sistema de programas NDRS (Neurosurgical Deep Recording System) sustituye con un ordenador personal el complejo equipamiento electrónico para el registro y procesamiento de la actividad eléctrica cerebral profunda, como guía de la neurocirugía funcional estereotáxica; asimismo, permite mayores posibilidades de representación de la información de forma gráfica directa, su manjeo automático y la flexibilidad suficiente para implementar diferentes análisis. Objetivo. Este trabajo describe las posiblidades automáticas de representación gráfica simultánea en trs planos casi ortogonales, ofrecidas por la nueva versión 5.1 del NDRS, para facilitar los análisis de correlación antomofisiológica en la localización de estructuras cerebrales profundas durante esta cirugía de mínimo acceso. Material y métodos. Esta nueva versión puede mostrar automáticamente el comportamiento espacial de la amplitud de las señales registradas a lo largo del trayecto del electrodo dentro del cerebro, superpuesta simultáneamente sobre los correspondientes cortes sagital, coronal y axial de un atlas anatómico cerebral, tras su escalamiento automático de acuerdo con las dimensiones del cerebro de cada paciente. Ello también puede mostrarse en una representación tridimensional de los diferentes planos interceptados entre sí. Resultados. El sistema NDRS se ha utilizado con éxito en España y Cuba en más de 300 intervenciones neuroquirúrgicas funcionales. Esta nueva versión facilita aún más los análisis de correlación espacial anatomofisiológica para localizar las estructuras cerebrales. Conclusión. El sistema ha contribuido a incrementar la exactitud y la seguridad en la selección de los blancos quirúrgicos para el control de diferentes síntomas de la enfermedad de Parkinson y otros trastornos del movimiento(AU)

[Neurophysiological monitoring in the treatment of pain]. / Monitorización neurofisiológica en la terapia del dolor.

INTRODUCTION: The concept of transynaptic deafferentation secondary to a lesion is the basis of the therapeutic criteria of functional neurosurgery. DEVELOPMENT: Pain due to deafferentation requires clinical neurophysiological techniques for characterization, and when appropriate, for localization of the level of the lesion and the ectopic focus or foci which cause the pain syndrome. However, monitoring therapeutic interventions in the pain clinic is an ever increasing need, and obliges the clinical neurophysiologist to master the range of techniques involved in his specialty, so that he can use the most suitable techniques and methods as required by each condition and/or case. The use of techniques such as micro-recordings of the unitary or multiunitary activity of the nerves or nuclei, intracerebral evoked potentials, nociceptive evoked potentials, reflexology, polysomnography and topography, together with techniques such as percutaneous objective localization of deep nerves, allows quantitative evaluation pre-, intra- and postoperative. CONCLUSION: The development of neuromodulation, and in particular of acute or long-term neurostimulation by use of percutaneous techniques, offers an effective therapeutic option in the field of clinical neurophysiology.

Monitorización neurofisiológica en la terapia del dolor / Neurophysiological monitoring in the treatment of pain

Introducción. El concepto de desaferentización transináptica secundaria a una lesión es la base del criterio terapéutico de la neurocirugía funcional. Desarrollo. El dolor por desaferentización requiere de las técnicas de la neurofisiología clínica para su caracterización y, en su caso, para la localización del nivel lesivo y del foco o focos ectópicos que pueden estar generando el síndrome de dolor. Sin embargo, la monitorización de las intervenciones terapéuticas en la clínica del dolor constituye una demanda cada vez mayor, que obliga al neurofisiólogo clínico a dominar la globalidad de técnicas que conforman su especialidad, con la finalidad de implementar ante cada proceso y/o cada caso en particular las técnicas y metodologías apropiadas y adecuadas. La implementación de técnicas como el microrregistro de la actividad unitaria o multiunitaria de nervios o núcleos, los potenciales evocados intracerebrales, los potenciales evocados nociceptivos, la reflexología, la polisomnografía y topografía, junto a técnicas como la localización objetiva percutánea de nervios en profundidad, permiten la valoración cuantitativa pre, intra y postintervención. Conclusión. La evolución de la neuromodulación y, en particular, la neuroestimulación subaguda o crónica, mediante la utilización de técnicas percutáneas, abren un camino de impacto para el ejercicio profesional del neurofisiólogo clínico en el ámbito terapéutico (AU)

[Stereotactic target identification for neurosurgery of Parkinson disease]. / Identificación de las dianas estereotáxicas en la cirugía de la enfermedad de Parkinson.

INTRODUCTION: The use of applied neurophysiological methods to improve the stereotactic localization of devices in the deep human brain is a high and systematic technology in Parkinson's neurosurgery today. The available standard equipment for clinical neurophysiology practice may constitute the basic set for high tech functional neurosurgery. Free run and event related multiunit recording, naturalistic and electrical evoked potentials, and deep brain microstimulation responses are the basic methodological set to neurophysiological target localization. DEVELOPMENT AND CONCLUSIONS: This article is concerned with the topic: set out a high technology using low cost equipment. So our 41 cases experienced in pallidal and thalamic nucleolisis and thalamus and subthalamus DBS results suggest that the proposed equipment and methods are the required to assure accuracy and safety for target location.

Changes in arterial blood pressure induced by percutaneous thermocoagulation of the trigeminal ganglion and rootlets.

The changes in arterial blood pressure which occur during the different steps of thermocoagulation of the trigeminal ganglion and rootlets are reported. The arterial blood pressure of 54 patients with trigeminal neuralgia was recorded continuously by catheterization of the radial artery. The maximal values were recorded (a) during the analgesic-sedation stage; (b) when the electrode came into contact with the base of the cranium during movement of the needle towards the foramen ovale; (c) during insertion of the electrode into the foramen ovale, and (d) during the thermocoagulation. One-way analysis of variance and Student's t test were used for analysis of the data. There was a significant increase of arterial blood pressure during the various stages of thermocoagulation.

Changes in hypothalamic met-enkephalin levels of rats induced by painful stimulation and morphine treatment.

The possible influence of painful stimulation and morphine analgesia on hypothalamic met-enkephalin levels, and the possible correlation between this biochemical parameter and animal behaviour was studied. The results indicate that both painful stimulation and morphine treatment induce an increase in hypothalamic metenkephalin. On the other hand, naloxone did not cause any variation. In animals submitted to painful stimulus, morphine treatment induced a decrease in hypothalamic met-enkephalin levels. Finally, when both morphine and naloxone were administrated before nociceptive stimulation, much higher levels were measured. There was no correlation between the level of hypothalamic met-enkephalin and the pain rating.

[An experimental pain model: the formaldehyde test]. / Un modelo de dolor experimental: el "test" del formaldehído.

Some papers have been published in relation to alternative models of experimental pain in animals. In this work, with the aim of proving the validity, safety, reproducibility and objectivity of this model, we have compared the behaviour of the animal under the formaldehyde test before and after the intracerebroventricular administration of morphine, proving itself as an ideal model for the study of chronic pain caused by an excess of nociception.

[Determination of the levels of methionine enkephalin in the blood and CSF and of 5-hydroxyindoleacetic acid in the CSF, following intrathecal administration of morphine]. / Determinación de niveles de metencefalina en sangre y LCR y de 5 hidroxiindolacético en LCR, tras administración de morfina intratecal.

The authors measured enkephalin and 5-HIAA levels in the CSF and enkephalin levels in plasma, after intrathecal morphine in 15 patients with terminal cancer.