stereotaksia

Stereotaksia is a set of biomedical techniques that use a three-dimensional coordinate system to locate small targets within the brain and to perform precise interventions. The aim is to translate imaging data into physical coordinates so that instruments can reach a defined anatomical target with millimeter or submillimeter accuracy. Applications include diagnostic biopsies, therapeutic lesions, targeted drug delivery, and electrode implantation for stimulation or monitoring.

The development of stereotaksia emerged in the mid-20th century with frame-based systems that immobilized the head and used external landmarks and radiographic images to determine target coordinates. Over time, frameless neuronavigation and multimodal imaging—combining computed tomography, magnetic resonance imaging, and functional imaging—improved accuracy and flexibility. Modern approaches often integrate robotics and computer-assisted planning to enhance precision and safety.

Procedure and workflow typically involve immobilizing the patient’s head in a stereotactic device, acquiring imaging data, and establishing a coordinate system anchored to the device. The target is identified on the images and converted to stereotactic coordinates. A guiding instrument, such as a biopsy needle, probe, or electrode, is advanced along a planned trajectory under image guidance to reach the target. In some cases, real-time imaging or functional mapping is used to refine placement.

Applications extend beyond neurosurgery to areas like radiosurgery, where a fixed coordinate system directs focused beams, and to research settings for functional mapping of brain networks. Safety considerations include the risks of hemorrhage, infection, or misplacement, mitigated by meticulous planning, image guidance, and verification steps.

See also: stereotactic frame, stereotactic radiosurgery, deep brain stimulation, neuronavigation.