The role of frameless stereotactic techniques in the treatment of pediatric CNS lesions.

The surgical management of children with deep-seated lesions within the brain and skull base or with superficial lesions within functionally important regions of the brain is often challenging. In order to optimize the functional outcome of an affected child, it is essential not only to adequately treat the offending lesion, but also to minimize injury to the surrounding brain. In this study, we examined the applicability of a video-interactive frameless stereotactic system for intraoperative localization and treatment of a variety of pediatric central nervous system problems, including craniotomy for tumor (n = 14), vascular malformation (n = 3), or cortical resection for intractable epilepsy (n = 4); ventricular puncture for shunt insertion in a patient with slit ventricles (n = 2); transoral odontoid resection (n = 1); cannulation of a brainstem syrinx (n = 1); removal of a foreign body (n = 1); and posterior craniocervical decompression (n = 1). The efficacy of the system was judged on several criteria: (1) the accuracy of the targeting achieved; (2) whether the system facilitated treatment of the lesions of interest; and (3) whether neurologic function was preserved. In general, the accuracy of the system for target localization was within 2-4 mm when rigid head fixation was employed intraoperatively. In such cases, frameless stereotactic guidance was extremely helpful in providing rapid and reliable assistance with operative planning, which facilitated the treatment of a variety of lesions in critical areas of brain with minimal neurologic morbidity. Limitations of this technology and potential solutions to these shortcomings are discussed. We conclude that the application of frameless stereotaxis for intraoperative localization represents a major advance in the treatment of a variety of intracranial processes in children by providing a means for accurately directing the approach to and removal of a targeted lesion while minimizing injury to the surrounding brain.