RESUMEN
Sixty-two cases of thalamic pallidal and subthalamic surgery in Dundee were audited to assess the influence of physiological localisation on the procedure. Methods included microelectrode recording, evoked potential and stimulation techniques. Although anatomical localisation is improving with modern techniques, the physiological information is still modifying the surgery in 67% of cases.
Asunto(s)
Mapeo Encefálico/métodos , Globo Pálido/cirugía , Auditoría Médica , Monitoreo Intraoperatorio/estadística & datos numéricos , Trastornos del Movimiento/cirugía , Núcleo Subtalámico/cirugía , Tálamo/cirugía , Mapeo Encefálico/instrumentación , Estimulación Eléctrica , Electrodos Implantados , Potenciales Evocados Somatosensoriales , Potenciales Evocados Visuales , Globo Pálido/fisiopatología , Humanos , Imagen por Resonancia Magnética/estadística & datos numéricos , Microelectrodos , Monitoreo Intraoperatorio/instrumentación , Monitoreo Intraoperatorio/métodos , Trastornos del Movimiento/fisiopatología , Cuidados Preoperatorios , Técnicas Estereotáxicas/estadística & datos numéricos , Núcleo Subtalámico/fisiopatología , Tálamo/fisiopatología , Tomografía Computarizada por Rayos X/estadística & datos numéricos , Resultado del Tratamiento , Vías Visuales/fisiopatologíaRESUMEN
The unforgiving nature of the thalamus, the globus pallidus and the subthalamic nucleus necessitates precise localization of functional targets. This requires the total attention of both the patient and the surgeon. To maximize the concentration of the patient and provide the most accurate localization, we performed staged stereotactic functional procedures. The first stage was performed under general anesthesia to abolish any head movement. We fused CT and MRI images and correlated the fused images with a digitized Talairach brain atlas. We calculated the target coordinates and fixed a modified Bennett Sphere to the skull with the central hole defining the trajectory to the target. The surrounding 12 holes gave parallel trajectories to targets surrounding the anatomical target at 2-mm intervals. The second stage was performed at least a week later under local anesthesia. Microelectrode recording using three simultaneous channels was used to refine the target. Once the microelectrode recordings and macrostimulation confirmed the desired target, a lesion was created or an Activa neurostimulator was inserted. Our early results using this technique in 28 procedures (in 19 patients) indicate a good outcome in 86% and a technical failure in 1 patient.
Asunto(s)
Diagnóstico por Imagen , Neurocirugia/métodos , Técnicas Estereotáxicas , Estimulación Eléctrica , Electrónica Médica , Humanos , Complicaciones Intraoperatorias , Imagen por Resonancia Magnética , Microelectrodos , Tomografía Computarizada por Rayos X , Resultado del TratamientoRESUMEN
OBJECTIVES: This investigation sought to develop a mapping apparatus for use in the assessment of both tooth and restoration wear. METHODS: A computer controlled mapping device, capable of scanning a suitably prepared electroconductive tooth replica by means of an electrical feedback mechanism, was constructed and its accuracy assessed by measuring the thicknesses of four engineers' slip gauges 12 times each. The reproducibility of three potential methods of rendering a die stone replica electroconductive was also investigated. Finally, tooth replicas were surface profiled and compared empirically with the originals using a commercial surface mapping program. RESULTS: The overall mean accuracy of the mean thicknesses of the slip gauges was 4.4 (2.8) microns. Surface deposition of either nickel spray or gold leaf, upon a ready formed replica, did not give a reproducible thickness. Precoating silicone impressions with nickel spray prior to replica production overcame this problem. On an empirical basis the instrument yielded accurate digital terrain models of tooth replicas. CONCLUSIONS: A surface mapping device has been developed which is both accurate and reproducible. A satisfactory electroconductive surface may be produced upon a tooth replica by precoating a silicone impression with nickel spray before casting the replica. The technique should prove invaluable for monitoring both tooth and restoration wear but further work is necessary to examine how such an approach will perform clinically.
Asunto(s)
Alisadura de la Restauración Dental , Atrición Dental/diagnóstico , Materiales de Impresión Dental , Diagnóstico Bucal/instrumentación , Conductividad Eléctrica , Diseño de Equipo , Humanos , Microscopía , Modelos Dentales , Níquel , Reproducibilidad de los Resultados , Procesamiento de Señales Asistido por Computador , Elastómeros de Silicona , Propiedades de Superficie , Tecnología Odontológica/instrumentaciónRESUMEN
Measurements of resting potential carried out in vivo in the dystrophic hamster and also measurements of muscle excitability showed no difference between dystrophy and healthy animals.