Endoscopic and Endoscopic-Assisted Microsurgery of Intraventricular Lesions: Efficacy of Technique and Outcome Assessment

Lesions within the ventricular system present a challenge to neurosurgeons (1). Their deep location and proximity to eloquent neurovascular anatomy complicate surgical approach and resection (2). Microsurgery remains the gold standard for the treatment of intraventricular tumors, but microsurgical approaches are not without limitations (3). With the use of the operative microscope, most lesions of the lateral and third ventricles are accessed by a craniotomy and either a transcortical or interhemispheric transcallosal approach. These approaches are associated with brain retraction that can result in seizures, focal neurologic deficits, and cognitive impairment (1). Also with standard microsurgical techniques, complete resection is sometimes not achieved either because of nonvisualization of hidden parts of the tumor or requirement of significant retraction of the neurovascular structures which is potentially hazardous (4). The addition of the endoscope for resection of intraventricular lesions has been described and represents a minimally invasive approach that limits brain retraction and provides direct lesion visualization (1,5,6). The recent development of endoscopic instrumentation has greatly enhanced microsurgical access to the ventricular system and would allow enhanced microsurgical access, minimize the size of the transcortical corridor, and reduce brain retraction during removal of challenging intraventricular lesions performed with the surgical microscope (7). The application of the endoscope can be used in the treatment of intraventricular lesions as arachnoid cyst with intraventricular extensions, colloid cysts, biopsies and intraventricular brain tumor removal (8). Reestablishment of CSF communication pathways is also possible endoscopically when patients develop obstructive hydrocephalus due to their intraventricular pathology (1). The biggest issues when it comes to a pure endoscopic approach concern the size and extent of the lesion, possibility of complete cure or at least long-term control of the disease, and the presence of remnants that were not completely excised (8) , However, The desire for a less invasive technique and an effective surgical approach to intraventricular pathology has directed the attention of many in the neurosurgical community towards the introduction of the endoscope as an adjuvant to or even a replacement for the microscope in intraventricular surgery (5) and consequently, neuroendoscopy has grown rapidly in the last 25 years as a therapeutic modality in the treatment of intraventricular pathologies (9,10).