RESUMO
Objetivo: describir la nueva técnica de callosotomía posterior utilizada en cirugía de epilepsia, junto a sus indicaciones, ventajas comparativas y sus resultados. Métodos: se muestran en secuencias de video dos casos de callosotomía posterior, en pacientes con epilepsia refractaria severa, con crisis tipo "drop attacks" (pérdida súbita del tono postural), presentando traumatismos a repetición, con potencial riesgo de vida. Ambos pacientes, una mujer de 35 años y un varón de 24 años de edad, presentaban una malformación congénita del desarrollo cortical denominada doble corteza. Un caso fue operado en posición semisentada, con abordaje parafalcino derecho, el segundo en decúbito ventral, con abordaje parafalcino izquierdo. Se realizó una incisión vertical parasagital de 7cm, a 2 cm de la línea media, con límite inferior en el inion y superior en la unión de la sutura sagital y lambdoidea. Se realizó una craneotomía de 5 x 5cm, exponiendo el seno longitudinal superior. La anatomía venosa de la región permite sin inconvenientes el desplazamiento lateral occipito-parietal. Se realizó una callosotomía que incluyó esplenio y cuerpo llegando anteriormente al sector que une ambas áreas motoras suplementarias. Resultados: no se presentaron complicaciones postoperatorias. El síndrome de desconexión apareció en un caso, desapareciendo en un periodo de 2 semanas. Se obtuvo una reducción del 90% de crisis, mejorando la calidad de vida y otorgando un mayor grado de independencia a ambos pacientes. Conclusión: la callosotomía posterior es un procedimiento seguro, poco invasivo y altamente efectivo contra las crisis de drop attacks en epilepsias refractarias
Objective: to describe the new technique of posterior callosotomy applied to epilepsy surgery, including its indication, comparative advantages and results. Methods: two surgical cases are presented on video sequences, including patients with refractory epilepsy, with "drop attack" type seizures (loss of postural tone), presenting with recurring trauma and a potential life risk. Both patients, a 35 years-old woman and a 24 years-old man suffered from a congenital malformation of cortical development known as double cortex. One of the cases was operated in a semi-sitting position, trough a right parafalcine approach, and the other one in a prone position trough a left parafalcine approach. A 7cm parasagittal vertical incision, 2cm lateral to midline was performed, considering its upper limit at the union of the lambdoid and parasagittal suture, and its lower limit at the inion. A craniotomy of 4 by 4cm was performed, exposing the superior sagittal sinus. The venous regional anatomy allows an easy parieto-occipital lateral retraction. The callosotomy included the splenium and the body reaching anteriorly up to the region where we find both supplementary motor areas. Results: no postoperative complications were found. One case presented with a disconnection syndrome, resolving in 2 weeks. A 90% reduction of the seizure frequency was achieved, improving the quality of life and the degree of Independence of the patients. Conclusions: posterior callosotomy is a safe, less invasive and highly effective procedure against drop attack type seizures in refractory Epilepsy
Assuntos
Epilepsia , Cirurgia Geral , NeurocirurgiaRESUMO
The role of cholinergic neurotransmission in male rat sexual behavior at the brain level has been studied by several researchers. However, little is known about its role at the spinal cord level. In this study, the effects of the intrathecal (IT) administration of the muscarinic receptor antagonist subtypes (MRAs) methoctramine (Meth), tropicamide (Trop) and 4-DAMP on male rat sexual behavior were evaluated during three ejaculatory series. Meth and Trop are preferring antagonists for the M2/M4 receptor subtypes, and 4-DAMP is a preferring antagonist for the M3 receptor subtype. All the MRAs tested noticeably inhibited male rat copulatory behavior, reflected by a reduction in the number of animals engaging in sexual behavior and a gradual decrease in the number of animals able to ejaculate. Significant increases in intromission latency (IL), ejaculation latency (EL) and post-ejaculatory interval (PEI) were observed. The ranking of inhibitory potency in all recorded parameters was Meth>/=4-DAMP>Trop. In theory, the effects of Meth and Trop could be a result of interaction with M2/M4 receptors. However, given that the M2 receptor constitutes the greatest population of muscarinic receptors at all spinal cord sites and given the high affinity for Meth on M2 receptors, the high potency in the inhibitory effects of Meth is indicative of the special role of M2 spinal receptors in the implementation of this behavior. The weaker effects of Trop could be linked to the smaller population of M4 receptors in the spinal cord, but some interaction with M2 receptors is probable. Since some differences in the pattern of inhibitory response between Meth and 4-DAMP were observed in this and a previous study, a possible role for M3 receptors must be considered. The data obtained in this study confirm the facilitating effect of acetylcholine (ACh) at the spinal cord level on male rat sexual behavior through muscarinic mechanisms, with an important influence on ejaculatory processes. These data support the hypothesis of the modulating role of ACh on male rat sexual behavior at the spinal cord level.
Assuntos
Antagonistas Muscarínicos/farmacologia , Comportamento Sexual Animal/efeitos dos fármacos , Medula Espinal/efeitos dos fármacos , Animais , Diaminas/farmacologia , Injeções Espinhais , Masculino , Piperidinas/farmacologia , Ratos , Ratos Wistar , Teste de Desempenho do Rota-Rod , Comportamento Sexual Animal/fisiologia , Medula Espinal/fisiologia , Tropicamida/farmacologiaRESUMO
Axons from receptors in the cat vaginal wall run in the sensory pudendal nerve (SPN), and brief (<10 s) vaginal probing (VP) in the decerebrate cat produces a long-lasting (>1 min) contraction of the triceps surae (TS) muscles. The aim of the present project was to find out whether brief SPN stimulation also produces sustained TS response and, eventually, to study the mechanisms involved in it. Decerebrate female cats were used. In some cats, TS electromyography (EMG) and tension response were recorded; stimulation of left SPN with single or repetitive trains of shocks produced a bilateral TS response that outlasted the stimulus >1 min as VP did. In paralyzed cats (pancuronium; Panc), intracellular recordings were made from hind limb motoneurons (MNs). SPN stimulation produced a depolarization