Intradural Extramedullary Tumor in the Lumbar Spine

Abstract

The management of intradural extramedullary tumors in the lumbar spine has evolved considerably from the technique described by Love in 1966 (Love JG. J Neurosurg 25(1):116–21, 1966). That evolution has marched in parallel with the developments in magnetic resonance imaging (MRI), intraoperative localization (the introduction of intraoperative fluoroscopy and image guidance), intraoperative neurophysiological monitoring, and minimally invasive techniques. Although the microsurgical techniques involved in the resection of these lesions remain essentially unchanged from Love’s technique, there has been a seismic shift in accessing the lesion within the spinal canal. The advancements in imaging and localization have allowed for precise monosegmental localization and exposure that result in less disruption of the native spine and thereby less postoperative discomfort for the patient. The minimally invasive paramedian approach builds upon the concept introduced by Yaşargil and Eggert in the 1980s and 1990s (Chiou SM, Eggert HR, Laborde G, Seeger W. Acta Neurochir (Wien) 100:127–33, 1989; Yasargil MG, Tranmer BI, Adamson TE, Roth P. Adv Tech Stand Neurosurg 18:113–32, 1991). The paramedian approach is a paradigm shift in conceptualizing the spine, whereby the midline elements, specifically the spinous processes, are not considered an obstacle to the central spinal canal. Paramedian approaches with minimal access ports allow for the necessary access to the entire central spinal canal for safe and complete resection of the lesion. The introduction and the synthesis of MRI, fluoroscopy, and paramedian minimally invasive approaches have transformed the resection of intradural extramedullary lesions. This chapter details the evolution of the paramedian minimally invasive approach, describes the surgical technique, and presents a case illustration.