Endoscopic approaches to the spinal cord.

Minimally invasive procedures have been used to treat various diseases in medicine. Great improvements in these techniques have provided intraventricular, transnasal and more recently cisternal intracranial accesses used to treat different conditions. Endoscopic approaches have been proposed for the treatment of disk herniation or degenerative disease of the spine with great progress in the recent years. However the spinal cord has not yet been reached by video-assisted procedures. This article describes our recent experience in procedures to approach the spinal cord itself in order to provide either diagnosis by tissue biopsies or inducing radiofrequency spinal ablation to treat chronic pain syndromes. We describe three different approaches proposed to provide access to the entire length of the spinal canal from the cranium-cervical transition, cervico-thoracic canal (spinal cord and radiculi) to the lumbar-sacral intraraquidian structures (conus medularis and sacral roots). We idealized the use of endoscopy to assist cervical anterolateral cordotomies and trigeminal nucleotractotomies, avoiding the use of contrast medium as well as vascular injuries and consequent unpredictable neurological deficits. This technique can also provide minimally invasive procedures to possibly treat spasticity through selective rhizotomies, assist catheter placements in the lumbar canal or debridation of adherences in cystic syringomyelia and arachnoid cysts, providing normalization of CSF flow.